Bulk material handling is the process of packaging, processing and/or transporting bulk materials in preparation for shipment or sale. Bulk materials include dry materials like wood chips, cereals, coal, loose stone and gravel, ore and sand, as well as mixed wastes. Bulk material handling equipment is used quite commonly in a number of industrial processes, including those in the construction, paper and pulp, logging and shipping industries. Often, bulk material handling systems are categorized by the types of materials they are designed to handle and/or the types of applications for which they are designed. Such materials include, of course, those mentioned above, along with any other dry materials in their bulk form. One common type of bulk material handling system is the system that handles materials for manufacturing. For instance, saw mills and paper mills often use bulk material handling systems to pick up sawdust, logs and woodchips for further manufacturing. This type of bulk handling system is also used to feed coal-fired utility boilers and in flour mills. Similarly, other bulk material handling systems are designed to transport materials for processing. This is the case systems that process ore for concentrating and smelting. Still other systems are designed simply to transport bulk materials from a source location to a final location. This is quite common when the goal of an application is inventory control or when the goal of an application is inventory storage.
Bulk handling material equipment can be made up of all kinds of individual pieces of equipment, depending on the application a system serves. Typically, though, they are composed of a mixture of stationary and moving equipment. Some examples of stationary bulk material handling equipment include: screw conveyors, conveyor belts, tubular drag conveyors, stackers, hoppers, wagon tipplers or railcar dumpers, bucket elevators and toploaders. Some examples of commonly employed moving or mobile equipment include: mobile hopper loaders and unloaders, shuttles, moving floors and various shuttles. To complete a bulk material handling system, systems may also be integrated into large structures, such as storage facilities like storage silos, stockyards or stockpiles. Bulk material handling, however, is not confined strictly to the land. Rather, bulk material handling systems are used all the time when loading and unloading cargo ships. In fact, increasingly, a type of bulk material handling equipment called the continuous ship unloader is replacing the gantry crane in ports around the world. Common examples of bulk cargo include grains (rice, wheat, maize, oats, barley, rye, etc.), gravel, coal, cements, dry edible agricultural products (livestock feed, peanuts, flour, seeds, raw or refined sugar, starches, etc.), iron, bauxite and petroleum or crude oil. To load bulk material onto a cargo ships, handlers may have to use equipment like a shovel bucket or a spout. Using items like these, they will pour or dump bulk cargo materials into the ship hold. This method can also be applied to the loading of bulk material into railroad cars or wagons and the bodies of tanker trucks, trailers or semi-trailers.
Bulk material equipment and systems are manufactured according to the task that each unit is supposed to accomplish, but most systems incorporate the same general components and features. A full system generally features:
An unloading station. The system must have an access point where materials can be discharged into the system. This portion of the system can take many forms, ranging from railcar unloading stations to a simple bag dumping station.
A conveying system. Most often bulk material handling systems utilize pneumatic conveyors, but other systems use screw conveyors, bucket elevators, or drag chain conveyors. Many systems use a combination of two or more of these different conveyors.
Material storage equipment. From huge storage silos to small bins or hoppers, a bulk material handling system should have a location where materials are stored until they are needed for processing.
Batching equipment. In order to utilize bulk materials efficiently, batching equipment is used to accurately dispense bulk materials for processing and for packaging.
A filling or packaging station. Once the bulk materials have been processed, the system needs a method for offloading the final product for packaging, shipment, or sale.
While practically all bulk material systems incorporate these main kinds of equipment, each system may use slightly different variations of the equipment and incorporate additional components to fit the specific needs of the application at hand. For example, in a food processing facility, a bulk material handling system would most likely use large storage silos instead of smaller storage bins, since they often handle such large quantities of grains, powders, and other materials. This sort of facility would also include mixing equipment in addition to the equipment above to thoroughly combine ingredients. Additionally, some systems are designed to better transport and handle materials comprised of very small particles, while others efficiently convey larger granules. These systems can be highly customized to fit the specific requirements of a given task or process.
There are a number of considerations that have to be made when bulk material equipment or systems are being installed. Not all equipment is made for use with all types of material, and the consistency of the material will greatly affect the quality of the final product. Some factors that should be considered during equipment selection are:
• Bulk density • Average particle size • Particle properties • Environmental effects • Material base
Experts recommend conducting extensive material tests before purchasing equipment so that the necessary processing qualities can be understood. For example, some particle densities actually change at different stages of the material handling process, so it should not be assumed that each piece of equipment will function efficiently at the same density level. Pneumatic conveyors are the backbone of most bulk material handling systems, so these considerations are incredibly important for determining which kind of pneumatic conveyor will transport specific bulk solids most effectively. Abrasive materials cannot be transported in the same way that a sticky material would be transported, for example. Some materials may transport more effectively using dense phase conveying, while others are effectively transported with dilute phase conveying methods. While these considerations are most vital for conveying systems, they do also affect other handling components, but to a lesser extent. Particle size and cohesion affect how materials can be combined together and can affect how the material is dispensed. Which means that material properties should also be considered for batching equipment, mixers, and material feeders.
Granulated and dry bulk materials such as grain, powdered chemicals, sugar, flour and dry cereal require specialized conveying, mixing and processing systems. These bulk material handling and powder bulk handling systems are designed for the integrated industrial mixing, conveying, measuring and packaging of delicate, friable, sticky or free-flowing solids. Unlike parts, equipment and other products which are conveyed through fabrication, assembly and packaging by belt and chain conveyors, bulk solids and powdered solids require a closed screw conveyor, flexible screw conveyor or pneumatic conveyor system which prevents caking, packing, liquefying, contamination and agglomeration. Industrial mixers, dryers, pulverizers and vibratory feeders are integrated into bulk material handling systems for complete processing.
Bulk bags are a type of bulk material handling equipment, constructed simply of flexible materials. They hold dry bulk materials exclusively; examples of these include plastic granules, sand, grains, fertilizer and other freely flowing materials. When empty, these containers weigh between five and seven pounds, but they can hold up to around one ton of dry bulk materials. When they are full, they can stand upright on a pallet without assistance, where a forklift can pick them up and move them without penetrating the material out of which they are made. Bulk bags are so strong yet lightweight because they are made of thick woven polypropylene or polyethylene, to which a coating is sometimes added to lengthen bag life. Also, to help move them around, bulk bags are also constructed with a strong loop at the top of each of their four corners. With these, it is even easier to pick up and move bulk bag equipment, particularly with forklifts, because forklift operators can slide these loops onto the machine’s forks. Bulk bags offer many advantages to their users, among them convenience, simplicity and cost reduction. Bulk bags are simple to make, inexpensive, reusable, space efficient and easy to unload.
Sometimes bulk bags are stored on pallets for long periods of time before they end up being used or emptied into a hopper for transfer to smaller packaging. Over time, the contents of the bag can settle and even lump together, creating flow issues during discharge. A piece of equipment called a bulk bag conditioner is used to deal with this problem. Many bulk bag conditioners are actually built into a bag discharger system. They operate by squeezing the bag from either side with mechanical arms while material is being released from the bottom. The back and forth motion of the arms against the sides of the bag dislodges any compacted material and restores an even flow. The arms of the bag conditioner are powered by hydraulic pressure. Because of this, they can generate a high level of power while still moving slowly and smoothly. Bag conditioners can also be used as an independent piece of equipment placed directly on the floor of a bulk material handling facility. If the bag is moved via forklift and placed on the machine, it takes just a few motions to dislodge the contents and prepare it for discharge. A bag conditioner can be operated using manual or automated controls. An automated system is the natural choice for bulk bag conditioners that are synchronized for use with other equipment like bag dischargers. A manually operated unit is best when the bag conditioner is used independently and the use isn’t necessarily constant. Some bag conditioners even have specially contoured plates attached to the ends of the squeezing arms to hold the bag and push against it at the same time. These plates come in contact with more surface area to dislodge more material in the bag. A number of bulk bag conditioners are built with a rotating pallet platform so that the bag can be turned while it is resting on the machine. This way the contents can be squeezed at intervals from all four sides instead of just two.
Bulk bag dischargers, or unloaders, provide efficient discharging of powders or other dry bulk materials from bags that were used to provide storage or easy transport for otherwise difficult-to-handle materials. Bulk bag unloaders are particularly useful in instances where the bags were taken from storage, because materials may have become tightly packed over time and much more difficult to unload manually. Any bulk material handling facility that deals with bulk materials in bags needs a bulk bag discharger on site to unload material efficiently.
Frequently used for unloading materials such as polymers, cement, soda ash, magnesium oxide, powders, grains, and hydrated lime, bulk bag unloaders offer dust-free material handling due to their enclosed, tubular design. Not only useful for a variety of materials, bulk bag unloaders can also be used with a wide range of bag sizes and styles including lined, unlined, polypropylene, mesh, wicketed, gusseted, and perforated. At times, bulk bag unloaders may also be used for flexible containers. As a cost-effective and safe means of unloading bulk bags, bulk bag unloaders are often used in industries such as chemical and food processing, construction, commercial, foundry, mining, and pharmaceutical.
Bulk bag unloaders are typically a fairly simple construction to which many accessories may be added depending on the requirements of the application. Bulk bag unloaders mainly consist of a frame, a hopper, bag support, typically suspension loops attached to the bags, and an outlet chute. However, there are many different frame configurations for bulk bag unloaders, the most common of which include forklift-style and chain hoist-style. Forklift-style bulk bag unloaders have pockets that allow for a forklift to easily load bulk bags into the bulk bag unloader. This type of bulk bag unloader is generally shorter than a chain hoist-style bulk bag unloader because it eliminates upper framework necessary to lift or position the bags. A chain hoist-style bulk bag unloader enables loading of the bags without a fork lift, integrating a pneumatic or electrically powered hoist that allows an operator to lift, position, and support the bag for loading. A less common style of bulk bag unloader is crane-style. A crane-style bulk bag unloader uses a crane in much the same way that a forklift would be operated to load bulk bags. All styles of bulk bag unloaders allow for efficient material discharge for further processing or a longer term mode of storage.
A bulk bag filler is a piece of equipment used to hold empty bulk bags securely in place while they are filled with material.
Manufacturers create several different types of bulk bag fillers, but they all achieve the same function in more or less the same manner. A steel frame with a platform houses the empty bag, and material is loaded into the bag from a filling hopper or pneumatic conveying system. Some bulk bag fillers hold the empty bag upright in a vertical position at its full height while the material is loaded directly from a chute and the bag slowly begins to fill. Once the bag is full, it can be removed from the machine using a forklift that either lifts the pallet below the bag or lifts the bag using the heavy duty loops on top. For bulk material settings where abrasive or delicate material particles are being handled, another type of bulk bag filler is used. On this type of bag filler, a single post extends upwards from the base of the machine, and the filling unit travels up and down this post. The bag loops are attached to the unit, and the bag is gradually pulled up as it is being filled. This method reduces the distance that the bulk material has to drop into the bag, resulting in a much gentler material transfer.
Bulk bag fillers with dust control can also be purchased to minimize the dust created in a facility during material transfer. Some units have a sealable valve that transfers the material from the chute to the bag without ever exposing it to the air outside. For sanitary needs, bulk bag fillers can be made from stainless steel for easy cleaning and resistance to corrosion. There are many variations of bulk bag filling machines, and sometimes manufacturers must construct them for very specific industrial applications using a set of specifications from the customer. Bag fillers increase efficiency in a bulk material operation and provide operators with a simple and clean way to transfer material for shipping or storage.
Pneumatic conveyors and screw conveyors are both types of bulk material handling equipment. The goal of both of them is to convey bulk materials from from Point A to Point B within an industrial system. Commonly, conveyors are used for bulk handling in industries including: mining, food and chemical processing, pharmaceuticals, agriculture, metalworking and more. Pneumatic conveyors and screw conveyors are different from one another based on their respective mechanisms of conveyance. First, pneumatic conveyors move materials using vacuum pressure created in a fully enclosed tube. This pressure forces or pulls materials from one location to another. Screw conveyors, on the other hand, move materials using a rotating screw located inside a trough or tubular casing. As the screw rotates, the materials in front of it are pushed forward. Each type of conveyor offers its own advantages. First, pneumatic conveyors, unlike traditional conveyor systems, can contain and rapidly transport fine particles. Also, they have virtually no moving parts and they are incredibly clean. Screw conveyors, though, offer not only transportation services, but the potential agitation, mixing or breakdown of materials as well. Also, because they are completely enclosed, users can be confident that no material will be lost in transit.
Flexible screw conveyors are materials handling equipment that involve the use of a rotating screw within a tubular or polygonal conveyance channel. When a motor turns the screw, the material within the channel is forced upwards as the screw turns.
The defining feature of flexible screw conveyors is their flexibility compared to rigid screw conveyors. Many bulk material handling systems incorporate screw conveyors to move material upwards or from a hopper into the processing line. Screw conveyors offer a few advantages over other conveying systems in certain situations. For example, in the conveyance of powdered, granulated or other very fine materials, belt conveyors can be an inappropriate choice; the materials can become ground into the belting, and they can escape the belting and accumulate around other conveyor components, such as rollers. Because screw conveyors completely enclose the materials they convey, and because the only moving part in a screw conveyor is the turning screw, there are fewer opportunities for product loss or equipment damage.
Also, screw conveyors can be used to transport materials vertically. Vertical and inclined screw conveyors are common tools in the agriculture, mining, manufacturing, and many other industries because they can assist in the loading of raw bulk materials into processing or storage equipment. These conveyors are usually equipped with an inflexible conveyance channel; in most cases, channel flexibility is not a necessary feature. In other cases though, such as in the case of portable screw conveyors, flexibility can make storage and use of screw conveyors easier. Portable screw conveyors are useful tools in a number of bulk material handling contexts. One prominent example is in agriculture; portable screw conveyors can be used to transport granular particles like harvested grain into storage equipment.
Because the screw conveyor equipment is moved from one area to another, and because it is used to load materials into storage equipment of varying shapes and sizes, flexibility of the conveyance channel makes the use of multiple screw conveyors of different sizes unnecessary. Some flexible screw conveyors’ conveyance channels can be adjusted in terms of their incline in a range of up to 90° relative to the ground. Flexibility aside, flexible screw conveyors are no different from other screw conveyor varieties. They are still powered by electric or gas-operated motors, and they are an affordable and effective alternative to other conveyor varieties. The flexibility just means that operators of a bulk material system can change the setup or configuration easily as demands change and production quantities go up or down.
Screw conveyors are bulk material transportation systems composed of a rotating, spiral screw inside tubular casing or a trough. As the screw rotates, dry or semi-dry bulk material is pushed forward through the conveyor from one area to another.
Screw conveyor systems, also called auger conveyors, helix conveyors, worm conveyors and flexible screw conveyors, handle all kinds of different substances, including powder, sludge, dust, flakes, granules and other loose products like seeds, food waste, wood chips, cereal, grain, boiler ash, fuels, feed and cement. In addition to transporting materials down a linear plane, industrial screw conveyors also aide in the mixing, agitation or breakdown of some substances due to their rotating motion with the screw's paddles. While most are made out of metals like aluminum and steel, some plastic screw conveyors are used in high heat, sanitary and high impact applications. The screw and bulk materials that are being conveyed are held in a trough or wholly incased. Tubular screw conveyors completely cover the screw, ensuring that no material will be lost in transit. Whether they are stationary and permanent or portable screw conveyors, these bulk handling systems are positioned at a number of orientations. Standard conveyors are horizontal, while some vertical screw conveyors lift material straight up and down. Inclined screw conveyors are positioned at an angle and are considered flexible conveyors if they can alter or bend in some way.
A pneumatic conveyor uses vacuum pressure in a fully enclosed tube to pull or force materials from one point to another.
A pneumatic conveyor is an excellent alternative to conventional mechanical conveyors with moving parts that are out in the open, because a pneumatic conveyor can contain fine particles and move them more rapidly. This creates a superior system for powder handling, particularly when you consider that there are no moving parts for the powder to get caught up in along the way. Most bulk material handling systems use pneumatic conveyors because they are efficient, cost-effective and clean. Because the system is fully enclosed, it greatly reduces any dust or wasted material during transfer. Without a fully enclosed conveyor, it is very difficult to completely protect the material from any kind of contamination during processing.
There are many components involved in the construction and operation of a pneumatic conveyor. It all begins with the air compressor that creates pressurized air in the system. The compressor pulls in air from the surrounding atmosphere and decreases its volume while increasing its pressure at the same time.
This results in a vacuum that has enough force to move particles. The system is also equipped with a bin vent filter to filter out dust when the material is entering or exiting the conveyor for storage areas like a silo. The arrangement of the piping or tubing in a pneumatic conveyor system is very important. Because this piping doesn’t need large platforms like a mechanical conveyor, the piping can be designed to avoid obstacles in a plant and create a network that sends material through the whole facility. Customized system designs make it possible to work around existing structures and integrate pneumatic systems into large commercial facilities.
Although a pneumatic conveyor is a specific type of conveyor that is notably different from a mechanical conveyor, there are two different sub-types of pneumatic conveying systems that should be distinguished for their various features and benefits. There are dilute phase pneumatic conveyors, and then there are dense phase pneumatic conveyors, and each is optimal in a different setting. Read on for a detailed description of each.
The first type of pneumatic conveyor is a dilute phase pneumatic conveyor.
Video Source: Dwyer Instruments
Dilute phase conveying is a high-velocity process that makes use of positive or negative pressure to push/pull materials through a tube. The dilute phase is most often used for fine materials, although it can be used for almost any fragmented material including wood chips, grains, etc. Because it can be used in applications where product degradation and high material velocities are never an issue or concern, dilute phase conveyors are often found in food and chemical processing, pharmaceutical, mining and even dairy. Dilute phase conveying can be done using positive or negative pressure, with each pressure type working best for particular applications. For example, positive-pressure dilute phase conveyors are best suited for conveying materials loaded from a single entry point to one or multiple destinations.
Positive-pressure systems can transport materials over a relatively long distance and use a minimum quantity of air to move the material. In the same way, negative-pressure dilute phase conveyors work best when transporting materials loaded from numerous inlet points and discharging them to a single point. Furthermore, there are several dilute phase conveyor system designs. A closed-loop dilute phase conveyor uses an inert gas as the conveying medium to convey the material in a closed-loop system. This type of dilute phase conveying is useful for handling hazardous chemicals. The primary advantage of a dilute phase conveying system is that it suspends particles during motion and transports them at a high velocity to their destination while keeping them contained in a closed loop. This results in efficient and clean bulk material handling, which is highly desirable in many industries that regular handle bulk quantities of material.
Dense phase conveying, also referred to as non-suspension flow, is the other method of pneumatic conveying. The main differences between dilute phase and dense phase are pressure, the solids’ properties and the rate of conveying speed. More specifically, dense phase conveying deals with the transportation of abrasive, friable or heavy materials such as sands, soils, minerals, food, paper scraps and rocks.
Video Source: Nol-Tec Systems
Dense phase conveyors push materials through at a low velocity with a low air-to-material ratio. Often, dense phase conveyors use an air compressor to generate high pressure levels to move materials through the system at an average of 275 feet per minute. Industries that typically benefit from dilute phase conveyors include pharmaceutical, chemical and food processing, foundry, mining, plastics and cement. Since dense phase conveying is great for moving large quantities of materials, it is often used in bulk material handling applications. However, dilute phase conveying may also be used if the materials being conveyed are both lightweight and non-abrasive. A dense phase conveyor is an enclosed tubular conveyor that is operated through air pressure and is typically gravity or vacuum-loaded while discharging materials from the bottom; however, there are several different dense phase conveyor designs. The bottom-discharge design in particular lends itself well to dense phase conveying because the materials being conveyed are so densely concentrated that they will naturally deposit at the bottom. Movement within gravity-loaded dense phase conveyors is typically generated by a blower at the starting end of the conveyor, although vacuum-loaded dense phase conveyors pull products through using a high-powered vacuum located at the conveyor destination. When the material being conveyed is fluidized, it deposits at the bottom much like a deposit of liquid and is dragged, or pushed, along the bottom. In dense phase conveying, there are two different manners of flow: moving-bed flow and plug flow. Moving-bed flow occurs when the material is conveyed along the bottom of the conveyor pipeline, whereas plug flow occurs when the material is conveyed in units, called plugs, which are separated by air gaps rather than one fluid body.
A full dense phase conveying system has many mechanical components and pieces of equipment that work in tandem to process bulk material. The system funnels pressurized air into a vessel that is fed by the storage silo. This compressor is regulated by both an air receiver and an air control panel. Since different bulk materials will need different pressures to achieve motion, operators can input the appropriate pressure into the main control panel. The pressure pushes the particles through the tube and into a deceleration zone before dumping them in the receiving bin. This bin also has a controlled environment where the pressure can be regulated externally using an interface with a set of operator-friendly controls. The main advantage of a dense phase conveying system is that it has the ability to transport heavy materials and particles because of the extremely high pressure that it creates. A low velocity system requires less air and is gentler on materials, which in turn reduces wear on the system’s equipment. Many industries who deal with bulk materials on a regular basis employ a dense phase system because it doesn’t do extensive damage to large particles during motion.
Pneumatic conveyors are a popular choice among many industrial facilities because of their efficiency, reliability and easy access for cleaning. Pneumatic conveying reduces dust and protect materials from contamination during transfer, making it one of the best solutions to the problem of how to move material. From agriculture to food processing to chemical engineering and beyond; pneumatic conveyors are relied upon every day to complete important functions and safely transfer products that end up in our homes and workplaces.
Mixers and blenders are, just as their name implies, industrial mixing and blending equipment, respectively. Mixers and blenders are used in agriculture, food processing, mining and pharmaceuticals, among others. In these industries, they’re used to create products like cosmetics, baking ingredients, fertilizer compounds, pet food and more.
It’s important that products achieve a consistency that is up to industry standards. That’s why mixers and blenders are equipped with precision speed controls and their internal temperatures and the radial reach of their mix components are carefully regulated.
Mixers and blenders can work with wet material or dry material, depending on their configuration. Those that deal with wet matter must be more powerful because wet materials generally result in heavier substances that still must be mixed at very high speeds. No matter the nature of material with which a machine is working, it must come with a seal that keeps dust and other particles from getting into the facility air. A great asset of mixers is the fact that you can easily remove their components for cleaning. Also, you can equip them with different attachments for unique material batches.
Common mixer/blender types include: auger mixers, high capacity mixers and ribbon blenders.
One of the most common types of mixers in a bulk material handling system is an auger mixer. An auger mixer is a powerful piece of equipment that has the capacity to quickly mix and blend bulk materials into a smooth consistency. Most auger mixers stand vertically in a facility on a sturdy metal frame. The auger is powered by an external electric motor that turns the auger rapidly through the bulk material. Depending on the desired consistency, the auger attachment may be changed. A long auger will create a more even blend throughout the tank, while a short one will produce more fine contents on the bottom. Some auger attachments are built with a diameter that is almost as wide as the diameter of the inside of the tank. Materials are loaded through an opening in the top and then extracted after mixing via a pneumatic conveyor or a discharge door in the bottom of the mixing tank. Most auger mixers are constructed using stainless steel so that they can be thoroughly cleaned between uses. This prevents cross-contamination and material buildup that could be harmful to the equipment or the mixture itself. The head of the auger can be removed for cleaning outside of the tank or to add a different attachment.
The shape of the auger’s sharp blades move material on either side of it up the center and then down the walls of the tank. This continual cycling motion is what makes the auger mixer so effective. Some smaller auger mixers actually run horizontally. An access door allows the operator to open the top of the mixer and dump bulk materials in, and then the machine can be turned on to mix materials once the door has been closed. Doors on a horizontal auger mixer are usually made of transparent fiberglass so that the person operating the machine can monitor the change in the material’s consistency.
Large bulk material handling systems are built to handle high volumes of bulk material on a daily basis, and these systems need mixers that have a capacity to match their batch sizes. Large bulk handling systems are very costly, so they are most efficient when they can frequently process high volumes around the clock. To mix these batches, industrial facilities use one or several high capacity mixers. A high capacity mixer is usually built with a large central auger that churns material, much like a regular auger mixer. However, the difference is that the power put out by the auger and the sheer size of the mixing tank itself is much greater. A high capacity mixer looks more like a storage silo, with a hatch at the top to add materials to the tank. After mixing, materials can then be discharged into bulk bags or bins using the door at the bottom of the tank. A pneumatic conveying system can also be fitted to the top or side of the mixer to pull materials out once the batch is mixed. A high capacity mixer for industrial use can be built with well over 1000 cubic feet of capacity. A quality high capacity mixer can process large volumes of material without compromising the consistency and precision of the mixture.
Powerful variable speed motors turn the mixing mechanism and push through heavy materials to evenly blend them. A high degree of control over the exact speed of the mixer enables workers to mix batches with the exact same texture every time. Sensors and instruments attached to the mixer input information to the control unit and display important stats to operators in the facility. This information is used to optimize efficiency and maximize batch output. Performance issues can also quickly be identified and addressed with this information. High capacity mixers are used in industries and applications where high volume production is very important. This includes cosmetics, food processing, pharmaceuticals, and more. If you are handling bulk materials for use in a cosmetic product, for example, you need a large batch all at once otherwise, the cost of the product will be greater than the revenue from the final product.
A ribbon blender is a high-speed mixing unit for bulk material handling facilities. It is similar to an auger mixer, except the unit is usually built with smaller dimensions. The ribbon or auger in the machine is designed in a helical pattern that enables that machine to mix materials homogeneously and completely discharge a batch when the process is complete. Ribbon blenders come in vertical and horizontal mounting options, and the type and size of the machine is chosen based on the materials being processed and the space limitations of the bulk handling facility. The ribbon in the blender is set in a U-shaped trough. The screwing motion caused by the ribbon pulls material through this trough and then lifts it up, slowly forming a pile. After they have been picked up, materials blend by falling together into this pile. Once the blending process is finished, materials can be discharged from the ribbon blender by opening the door on the bottom of the tank. This door is opened using a lever or automated controls. The blender remains on as the door is opened, and materials fall through to a bin below as they are pushed by the ribbon to the center of the tank where the opening is. After the machine has been turned off, the access door can be opened and all of the parts can be cleaned.
Like most bulk material handling equipment, ribbon blenders are often constructed using stainless steel. Not only is this material strong and highly resistant to corrosion, but it is also very easy to clean. In some facilities, cross-contamination of ingredients is a major concern, so machines are all cleaned between batches. Ribbon blenders are used in many industries; from food to pharmaceuticals to cosmetics. Because of their balanced blending abilities and consistent mixing quality, ribbon blenders are an excellent choice for many bulk material handling facilities. The range of sizes created by blender manufacturers makes it possible for both small and large plants to utilize the efficiency of a ribbon blender in whatever space they have available.
Screening and separation is a joint process that is important to sorting of bulk materials. Screening equipment is used to sort bulk materials mechanically, while separation equipment is used separate raw bulk materials based on quality or particle size.
The most popular and common types of screen equipment are vibratory screeners and high frequency screens. The most frequently used types of separation equipment are magnetic separators, air separators and flotation separators. Depending on the nature of the application, any one of these machines may be used during material processing. Especially important in this decision is whether solids are being separated from solids, liquids are being removed from solids or vise versa. Other factors relate to material size.
Vibratory screeners, for example, are best used to separate materials by size. They vibrate to shake out small particles and remove clumps from material. High frequency screens, on the other hand, are best when used to separate fine particles. They use intense vibrations to separate materials like minerals from mines. Magnetic separators are also used in mining. There, they use a magnet to separate ferrous and non-ferrous metals.
No matter which screening or separating equipment you use, it will allow you to process large amounts of materials without compromising their quality.
Screening equipment is used to sort bulk materials with great attention to detail so that only the right particles end up in the final bulk stream. Unlike separating equipment, screeners sift materials mechanically. There are many different types of screening equipment that can be used in a bulk system.
The piece of equipment that is used depends on the industry and type of material being processed. Sometimes solids must be separated from solids, and in other applications liquids are removed from solids or vice-versa. While there is a long list of screening equipment, below are a couple of the most popular and common types among bulk material handlers.
Vibratory screeners are likely the most common piece of screening equipment in bulk applications. As the material moves across the screen, the machine creates vibrations that shake out small particles and remove clumps from the material. This is one of the most effective and efficient ways to separate materials by size. The size of the particles being sifted out can be determined by the pattern and shape of the metal screen and the rate of the vibrations. Vibratory screeners come in many different sizes and can process large volumes of material in certain applications. A linear vibrator is used to gently process dry goods by sifting them on a fine screen at a low frequency and in a stationary horizontal position.
High frequency screens use intense vibrations to separate fine particles in applications like mineral processing. An electromagnetic vibrator connected to the surface of the screen controls the intensity of the vibrations as materials are introduced to the screen from a conveyor. High frequency screens can be used as a secondary screening measure to remove fine particles before or after the primary screening process.
While high frequency screens and vibratory screeners are the most likely to be found in a bulk material handling system, other types of screeners that may be used include: rod decks, disc screeners and star screeners. Each of these is best suited to sort larger individual objects rather than the fine particles or granules that are typically processed in most bulk facilities. In recycling and waste recovery centers, disc and star screeners are usually used to separate recyclable materials based on their size.
Screening equipment in bulk applications allows bulk material handling facilities to refine and purify their materials before they are packaged or shipped to distribution centers. With the right piece of screening equipment in a system, bulk handlers can process material in large volumes without compromising the quality of their product or allowing it to be contaminated by unwanted debris. Applications for screeners vary greatly and can include agricultural products, pet food, bulk baking ingredients, pharmaceutical batches and more. Screening equipment is easy to maintain and designed to operate continuously for high volume production in a busy bulk material handling facility. Some machines are even self-cleaning, meaning that they remove debris from the mechanism without the need for manual cleaning between production runs.
When raw bulk materials are being processed, sometimes it is important to separate the materials based on quality or particle size. In some applications, the final product must be 100% pure, or may only be of value when it had been refined. While this can be accomplished manually, it is much more efficient when separation equipment is used to sort bulk material. Some of the most common pieces of material separation equipment for bulk applications are listed and described below.
Magnetic separators are important in the mining industry where they can be use to separate ferrous and non-ferrous metals. A magnetic separator can prevent harmful bits of metal from entering machinery further down the line, and they can remove impure or unwanted materials from a stream. The magnets pull out the unwanted material as the bulk materials pass by on a conveyor. A permanent magnetic separator does not need any electric power to operate. These mechanisms can last for a long time without requiring maintenance or losing a significant amount of strength. More powerful industrial magnetic separators may use coils and direct currents to create a stronger magnetic field.
To make sure that volume measurements in a bulk handling system are accurate, an air separator is used. As bulk material passes through the chamber of an air separator, air or gases are removed from the material. Vacuum technology is commonly used to suck all of the air out of a confined space so that the only remaining substance is the bulk material itself. An air separator can easily be integrated into a pneumatic conveying system as either side of the unit can be connected to pipes or tubes.
Flotation separators use the principle of buoyancy to separate bulk materials. Water is added to a large tank, and the water’s density can be altered using certain additives that help to create the desired effect. Next, the material is added to the water. As a result, only materials with a density greater than that of the water will sink to the bottom of the tank as the rest remain floating at the surface. Mechanical arms scoop up the floating materials and move them along to the next part of the system. Flotation separation is an efficient way to separate minerals from other particles and debris. The debris that has fallen to the bottom of the tank can be ejected through a discharge hatch or periodically cleaned out of the tank from above.
Materials separation equipment is used to sort particles in bulk material handling systems in industries that range from agriculture to pharmaceuticals to food processing, mining and beyond. With machines that can separate high volumes at such a rapid rate, bulk material handlers in some industries are able to process more materials in a day than they could by way of manual labor in a week. Technological advancements like this are what help to make bulk material operations so large and efficient today and enhance the many possibilities of bulk handling.
A vibratory screener is a stationary or portable piece of equipment in a bulk material handling facility that removes unwanted materials from a batch using vibrations. Materials are moved over a screen and vibrated in such a way that only the desired particles fall through, while larger debris is caught by the screen. If there is unwanted liquid in the material, a sieve type vibratory screener is used to separate the solids from the liquid. Sometimes the waste is recycled after cleaning if it can be broken down into a useable form.
Vibratory screeners are not just used to separate materials; they are also important for classifying bulk materials by size. The larger or smaller materials that are removed may not necessarily be unwanted, they might just need to be classified and packaged differently. Plastic pellets can be sized and screened using a vibratory feeder during the handling process. Although there is a wide variety of vibratory screening machines available on the market, some unique handling applications require customized screeners. Specialized manufacturers offer custom-built vibratory screeners based on the dimensions and processing needs of your facility.
There are a number of considerations that need to be made when you are purchasing a piece of vibratory screening equipment, or when you are working with a team of engineers to design one. First, you need to determine what vibration frequency works best for the material that you will be handling. This can be determined by testing with a vibratory screener at various frequencies to find the optimal setting. You will also need to find out how large the screen should be and what size the reservoir needs to be. The reservoir holds material or feeds it into the next stage of the process. The size of the screen and the reservoir below it will depend on the scale of the bulk material operation. However, even in a large processing facility, the vibratory screener cannot be too large or it will not screen material as thoroughly.
Vibratory feeders, also known as vibratory conveyors or vibratory bowl feeders, are bulk handling equipment used to to convey and sort materials. They consist of a vibrating unit, a bowl and a variable amplitude control box. Usually, they are also connected to a conveyor track. They are a favorite for use with sticky or delicate materials because they can convey them with liquefying them or causing them damage. Vibratory feeders convey and sort materials using vibrations and movement. The vibrations comes from the drive, which is installed underneath the bowl.
Vibratory feeders are generally simple in design and easy to run for extended periods of time. However, they do vary greatly from model to model. For example, some are built with troughs that sift material, while others have vibrating or trommel screens to convey and sort bulk products simultaneously.
Vibratory feeders are generally divided into two main categories: vibratory bowl feeders and vibratory conveyors. Bowl feeders used more for parts than for bulk material. They align products before packaging so that they are discharged into the package in the right positions. Vibratory conveyors, on the other hand, are used primarily to feed material from one point to another.
The term “industrial dryers” refers in general to dryers used for manufacturing, industrial or large-scale commercial purposes.
Industrial dryers can used to dry clothes and linens, as they are laundromats and hotels, but their range of applications is much wider than that. Rather, they are essential in many different industries including: agriculture, food processing, manufacturing, pharmaceuticals, pollution control, water treatment and paper and pulp. These industries count on industrial dryers to dry materials that come in contact with fertilizers, grains, chemicals, refuse, dairy products, minerals, papers, plastics and more.
Industrial dryers work using three main methods: air drying, infrared drying and spray drying. The first, air drying, is the most common. Air dryers work by bringing materials in direct contact with hot air, so that any moisture evaporates and diffuses into the air. Next, infrared dryers dry solid materials using electromagnetic radiation on a certain part of the wavelength. Finally, spray dryers work using jets of hot steam that cause moisture to flash dry and evaporate.
Industrial dryers come in a wide variety of makes and models. However, many share certain characteristics. For example, they are usually made from stainless steel. Learn more by contacting an industrial dryer manufacturing today.
Industrial dryers are used for removing moisture from substances, products or materials in a business or manufacturing capacity. Industrial dryers are often specialized or custom built for specific applications. They tend to be much larger than dryers found in a home or small business and usually don't dry laundry unless used in a laundromat or hotel.
The term "industrial dryers" is a general reference that applies to dryers no matter what their particular method of drying is: air, infrared or spray drying. Because of the variety, there is no single design or model of industrial dryer, though there are some shared characteristics. Many dryers are made from stainless steel because it is strong, sanitary and corrosion resistant. They are often cylindrical tanks or rectangular boxes with multiple intake and output valves, connections, openings, gauges and controls. Some may be continuous - able to dry a constant flow of materials - and utilize a conveyor belt while others work in batches. The capacity depends on the kind of dryer and the material that will be dried. Certain dryers can dry over 25,000 pounds an hour while others can be built to hold only one cubic foot. Dryers are essential for the pharmaceutical, food processing, manufacturing, agricultural, pollution control, water treatment and paper industries and have multiple functions when working with chemicals, dairy products, fertilizers, grains, minerals, paper, plastics, refuse and more.
Most industrial dryers are bolted or welded together, depending on the importance of the seams, the anticipated product and any motion the dryer will endure. The three main methods of drying encompass a variety of models that carry out the task in different ways. Air dryers are the most common industrial dryers. They bring materials into direct contact with hot air, which causes moisture to evaporate and diffuse into the air, leaving behind a dry product. Flash dryers, freeze dryers, fluid bed dryers and rotary dryers all fit in this category, though their designs vary. Flash dryers use a short, intense burst of heat to dry materials almost instantly while freeze drying uses cold air and vacuums to freeze moisture and sublimate it away. Fluid bed dryers shoot steam up through a perforated plate in order to cause the solid material to behave like a fluid; rotary dryers are large drums that dry products as they turn and tumble the material through the hot air contained inside. Infrared dryers rely on electromagnetic radiation from a certain segment of the wavelength to dry solid materials quickly and without overheating them because the wavelength can be matched to the absorption rate of the product to maximize energy and resources. Spray drying introduces the material to jets of hot steam, which causes the moisture to flash dry and evaporate.
Palletizers are machines used to load and unload pallets before and after shipping or storage. Material handlers use them to reduce the manual labor and increase the efficiency associated with moving, storing and shipping bulk material. Before placing bulk materials on a palletizer, handlers also make sure they are bagged. Typically, they do this using some sort of bagging equipment. Together, these two applications are known as bagging and palletizing.
To get material into bags, usually, a machine holds onto the bag as material is dumped into it. For convenience, material handlers can sometimes place the palletizer right underneath or beside this machine.
There are three main types of palletizers: low-level, high-level and robotic. Low-level palletizers receive packaged bulk materials at the ground level, where they then move them along a conveyor. Meanwhile, high-level palletizers is loaded from above. Robotic palletizers are usually placed in between a dispenser and a conveyor carrying incoming materials. Here, they picks these materials up and place them onto a pallet. Then, they moves the pallet to another area. Usually, all of the palletizer types are fully automated.
Bagging and palletizing is a common pursuit in industries including agriculture, food processing, chemical engineering and pharmaceuticals.
One of the unique challenges of bulk material handling is that goods must be moved in massive quantities. Often, these materials are very heavy and they require mechanical assistance to be moved around, stored, and shipped. To reduce manual labor and increase efficiency, bulk material handlers use palletizers. A palletizer is a machine that can load and unload pallets before and after shipping or storage. Since pallets are a standard means of storing and transporting bulk products in many industries, a palletizer is a versatile solution. Before bulk materials are placed on pallets by a palletizer, they must be bagged or put in a container of some kind. Typically, other equipment is used to accomplish this, and then the loaded bag or container is placed on the pallet by the palletizer.
If a bulk product is being bagged, the bag is usually filled by a machine that holds the bag as material is discharged into it. The palletizer may be underneath or beside this machine, and it is ready to accept the loaded bag on an empty pallet. Manufacturers of palletizing equipment make three different types of palletizers: low-level, high-level, and robotic. A low-level palletizer accepts packaged bulk goods at the ground level and moves them along a conveyor. A high-level palletizer is loaded from above. Usually, both of these types are fully automatic so that no manual intervention is necessary.
A robotic palletizer is typically placed between a conveyor with incoming materials and a dispenser. The unit can actually pick up these materials and place them on a pallet before dispensing the pallet to another area. A robotic palletizer can be programmed to work with many different types of bulk products and has a high weight capacity.
Adding a palletizer into a bulk material handling facility helps to further automate the system’s process and reduce the risk of injury or lost material during transfer. Palletizers are faster than manual labor, and there is less chance of human error causing an accident while materials are being loaded if a machine is used. Overall productivity, safety, and efficiency all benefit when a palletizer is installed. To improve safety and minimize the chance of damage to the equipment, many palletizing units have QuickSTOP collision sensors. These sensors detect any damage to the equipment and shut it down immediately before further damage occurs. Smartscan systems can also be added to palletizers to detect human movement near the equipment. If someone gets too close, the machine will automatically shut off.
While palletizers are powered by an electric motor, some heavy duty ones may uses hydraulics to raise and lower loaded pallets. Bulk material handling systems in almost every industry use pallets to transport their goods after they have been processed, so palletizers are a common piece of equipment. Industries like agriculture, food processing, pharmaceuticals, and chemical engineering all make use of palletizers to load products in a container or bag onto a pallet before shipping.
Palletizers come in a range of types and sizes, so the cost varies. However, the upfront cost of a palletizing unit is usually significant, but returns can quickly be seen as the volume of bulk material processed increases. Most bulk material handling facilities easily recoup the investment that they make in a palletizing unit.
Weighing systems and scales are incredibly important to bulk material handling applications in many different industries. These include agriculture, food processing, pharmaceuticals, mining and oil and gas, among others. They are so important because they ensure that bulk material handlers accurately weigh and package their products.
Scales and other weighing systems range greatly in terms of size and configuration. Some are quite small and can measure products down to the gram. Others are large enough to weigh entire loaded pallets or loaded trailers. They weigh loads using a variety of mechanisms, such as load cells, springs, balances or hydraulics. In addition, they may have either digital or analog displays.
Some common scale types include: platform scales, hanging scales and bench scales. Platform scales, also known as floor scales, are level with the floor. Usually, they come with a large platform on which large bulk loads can be weighed. Next, hanging scales, suspend loads in the air. They gauge weight based on the amount of gravitational force a load exerts. Finally, bench scales weigh mostly small and medium sized loads. They stand several inches or a few feet off of the ground, which makes loading and unloading easier. They are portable.
Load cells are used in bulk material handling systems to gauge the weight and force of a load of bulk material. The purpose of this ability is to test mechanical systems and monitor their output during production times. Load cells are particularly important for maintaining the accuracy of the industrial scales that are used to weight bulk products. Compression and tension are the most common force measurements made using load cells. Many load cells are built with an internal strain gauge, a small device that can measure how much strain is put on an object using electrical signals. Force gauges do the same thing but for push-pull testing or measurement of flow.
The flow of liquid or viscous bulk materials can be measured by pressure sensors. This is useful to determine the rate and force of flow through a bulk system for optimization and efficiency purposes. Digital load cells are the most popular and the most easy way to access the information that sensors pick up during operation. In food processing facilities, load cells play an important role in measuring ingredients before they are entered into a mixture. This precision is critical to the on-going quality of a product. Perhaps the most important function of a load cell is to determine the exact weight of loads, like a loaded pallet. When bulk processors ship their goods, they need to know the precise weight for logistics and billing reasons. Load cells provide readings that are accurate within 0.25%, which is extremely precise for applications where a single load may weigh several tons.
So how exactly does a load cell work? A load cell is designed to convert mechanical stress into electrical energy. Information is received in this way and sent to a data collection system in the device. This is then turned into an output or reading that an operator can see as an item is placed on a scale or material runs through a tube. Analog load cells still exists, but they have been largely surpassed by digital load cells because they are more accurate and easier to read. In applications where a load cell is used to shut off equipment, the cell is designed to sound an alarm when a predetermined event or set of criteria is observed. Load cells can be fitted with multiple gauges. The more gauges, the more sensitive the cell will be to changes and the more accurate its measurements will be. Necessary accuracy, type of force, and response time are among the most important factors that must be considered when a cell is being designed for an application.
Load cells are used in equipment at bulk material handling facilities in mining, food processing, pharmaceuticals, oil & gas, agriculture, and other industries. Although a load cell is very small, it has a huge impact on the efficiency and cost-effectiveness of major operations. Some manufacturers specialize in load cell production and work with industry experts to create devices that perform specifically for certain materials or applications. Others are more general and can be used in many different bulk handling capacities.
Bulk material handlers in all industries rely on scales to weigh their products and accurately determine quantities during packaging, before shipping, or before storage in a facility. Many bulk products are sold or distributed based on weight, so it is important that precise information is available. Scales can be small enough to measure tiny objects, but typically in bulk material handling applications, they are at least large enough to weigh a loaded pallet. Some industrial scales are large enough to weigh an entire loaded trailer or shipping container. Scales are made in many different forms, including: bench scales, hanging scales, and platform scales. A bench scale is raised up off of the ground by several inches or a few feet and may even be moved around a facility as needed. The raised stance of the scale makes it easier to load and unload small to medium sized loads. A platform scale or floor scale is level with the floor and typically has a large platform for weighing large bulk loads. A forklift or other vehicle can be used to move the weight directly onto and off of the scale. A hanging scale suspends loads in the air and gauges their weight based on the amount of gravitational force that they exert.
Scales can have either digital or analog readings. While a scale with a meter and a needle that displays the weight of a load may be accurate, it is not as precise or as easy to read as a digital scale. Digital scales show decimals and make it possible to be highly precise during the weighing of bulk products. In any bulk operation, the most important consideration when investing in an industrial scale is the maximum weight that it is able to measure. Scales can range from a capacity of just a few grams to over 80,000 pounds. Knowing the needs of your application and choosing a scale accordingly will prevent technical errors and allow for the accuracy that your system needs. When bulk products are weighed on a scale, they are usually on a pallet or loaded into some kind of container. The weight of the container or pallet itself can be inputted into the scale so that the only material being measured is the bulk material. If distributors are being charged by weight, it is important that a bulk handler does not also charge them for the weight of the container. To determine the weight of a load, scales are built with hydraulics, balances, springs, or load cells. In more complex scales, a combination of these devices is used.
In most industries, scales are subject to regulatory standards that have been established by the National Institute of Science and Technology. These standards ensure worker safety and accuracy for the measurement of bulk goods. In a bulk material handling system, scales can be placed near other equipment and loaded manually by workers, or they can be loaded and unloaded intermittently by automated machines. In these instances, the machines receive information from the scale that tells them when the load has reached the required weight. Bulk material handling systems in agriculture, food processing, pharmaceuticals, and more all use industrial scales to weigh products before they are packaged or shipped. Sometimes it is necessary to use scales to weigh small quantities that are then added to a larger mixture in a processing plant. Again, accuracy is key to maintain consistency and quality across bulk products in applications like these.
Weighing and batching equipment are integrated into bulk material handling systems to ensure that the appropriate quantity of material is utilized, packaged, or shipped. A weigh batching systems can be used to accurately fill containers like bags, drums, or bottles so that each container is filled with the exact same amount of material, or they can be used to ensure that an appropriate amount of materials is added into a batch being mixed. These systems provide accuracy and repeatability in bulk material handling systems. There are several types of weigh batching systems that are used in bulk material handling, and they use what are known as either gain-in-weight or loss-in-weight principles.
With a gain-in-weight batching system, a volumetric feeder is used to feed the material into a weighing hopper. As material is added, the weighing hopper continuously takes weight measurements, and the feeders continue to release material until a set weight is reached within the hopper which triggers a mechanism that signals the feeders to stop. Many applications require that several different materials be added into the batch. In this case, each material is added to the weigh hopper one at a time. Once the set weight for an ingredient is reached that feeder is switched off and the next ingredient feeder is switched on until the next set weight is reached. This process continues until all ingredients have been added. This results in the hopper containing several layers, one for each ingredient since they were added individually. The sensitive automated controls in this weighing system prepare bulk materials for the next stage of the process by carefully controlling the release of substances.
In a loss-in-weight batching system, multiple ingredients are fed into a collection hopper using highly controlled feeders. Each of the ingredient feeders is equipped with a weighing sensor, such as a load cell, to carefully measure the weight of the material within the feeder. As the feeders release material into a hopper, the system tracks how much of the ingredient is released by tracking how much weight was lost in the feeder. This is important in applications where smaller weights are at play and where more exact weight measurements are necessary. Additionally, batch mixing times are reduced down the line because these materials are introduced into the hopper all together instead of one by one, resulting in a blended mixture.
Within these two types of weigh batching systems there is a wide variety of machinery. Machines vary in sizes and can be purchased to reflect the availability of floorspace in a commercial or industrial facility. Because industrial technology has advanced so much in recent years with the development of better digital control and sensors, bulk material weigh batching systems can be more precise than ever before. Full control and display units can be installed in a facility so that operators can monitor efficiency and output. Changes can now be made at the touch of a button, a feature which is especially convenient for suppliers who process high volumes of material for many industries on a daily basis.
Industries like mining, pharmaceuticals, agriculture, chemical engineering, among others, deal with large volumes of bulk material on a regular basis. To make sure that their materials don’t spoil, get contaminated or wasted, it is important to all of these industries that they be able to properly store them. That’s why storage equipment is such an important component of bulk material handling.
Some of the most prominent types of storage equipment include hoppers, tanks and silos. Hoppers are designed to temporarily store bulk materials while they’re waiting to be transferred. To make it easy to empty materials into something else, hoppers have a discharge port at the bottom. Tanks are designed to store materials for longer periods of time, which is part of the reason that they are made of stainless steel. They are quite popular in agriculture, where they typically store crops and animal feed. They are also popular for in the pharmaceutical, food processing, medical and chemical processing industries. Silos are typically cone-shaped cylinders that store extremely high volumes of material. They have an access point at the top and an exit valve on the bottom that makes it easy to integrate them into conveyor and/or pneumatic systems.
A hopper is used to hold bulk materials before they are transferred into a conveying system, bag, or container for use or for distribution. The hopper is designed to temporarily store bulk materials until they need to be emptied out into something else through a discharge port on the bottom. When the port is opened, the contents pass through the hopper in a controlled flow to the next part of the handling process. Hoppers are typically manufactured using sheets of steel, due to its durability and the ease of manufacturing. The steel is generally formed into a conical or wedge-like shape to facilitate the movement of materials toward the outlet at the bottom of the hopper. At the outlet port, the hopper can be fitted with a variety of different components, depending on the requirements of a particular application. Some simply have a sealable port which can be opened to quickly dispense large quantities of materials.
Other hoppers may be equipped with valves for more controlled distribution of the contents. For example, hoppers used to feed materials into pneumatic conveying systems commonly use rotary valves to gradually feed materials into the conveying stream. Still other hoppers may use an auger to discharge material. These containment products are incredibly important in many different bulk material handling processes because they provide a means for controlling the dispensing of bulk products. For weighing and batching applications, they can be outfitted with sensors to track how much material they contain which is incredibly important for ensuring that a particular batch has the right blend of ingredients and the appropriate quantity of each ingredient. They also provide flow control for conveying systems. With the appropriate components, a hopper can help keep conveyors from being overloaded, which can lead to a variety of problematic consequences.
In fact, these products are so vital to bulk material handling that they are often built into or integrated into other bulk material handling products as standard. All in all, when it comes to bulk material handling applications, hoppers are a crucial component for material flow and control.
Tanks made of stainless steel are used to hold and store a variety of bulk substances. They are usually cylindrical, like drums, but their shape and orientation often varies-tanks are either horizontal or vertical and may hold anything from 1 gallon to millions of gallons. Stainless steel is chosen because of its corrosion resistance, which makes it useful for the storage of hazardous substances, resistance to high temperatures, and strength as well as the ease in which it can be manufactured and cleaned. Manufacturers of stainless steel tanks supply numerous industries where bulk material is handled, including agricultural, food processing, medical, and chemical management. They are commonly used where hygiene and corrosion are concerns. They are often used in the agricultural industry where they usually store animal feed and crops, in the pharmaceutical industry where they are used to store powders and chemicals, in the food industry storing bulk ingredients, and many other industries and applications.
Stainless steel has good thermal conductivity and thermal expansion rate, which is key to tanks of any sort, and particularly useful in the case of pressure vessels. There are many different types of stainless tanks that differ in properties depending on their applications. SS tanks always contain openings called manways, where contents are poured or accessed. Stainless steel tanks are thin-walled constructions manufactured through a rolling process or welding. Although stainless steel is strong, it is vulnerable to buckling when the material is thin. Stainless steel tanks are most susceptible to damage during construction, transportation, and installation. The contents of full stainless steel tanks actually aid its stability.
The shape of the tank is dependent on its diameter or height and the efficient use of material. Stainless steel tank manufacturers can make the ends of their products flat or in the shape of a dome or cone. In determining the size that a tank needs to be, consider how much extra volume should be included to cover for future process needs and also consider how the tank will be filled and discharged. The industrial applications where stainless steel tanks are utilized determine tank properties such as size, shape, and orientation. They are often vertical silos and horizontal or vertical storage tanks. Stainless steel is the material of choice for many industries because it is easily temperature controlled, cleaned, and sterilized. They must adhere to strict FDA, USDA and 3-A standards for health reasons. Tanks used to house foods are cleaned every time they are emptied and must maintain certain temperatures if they are holding perishable food items.
Industries like mining, pharmaceuticals, agriculture, chemical engineering, and more all deal with large volumes of bulk material on a regular basis. Silos are built in many different sizes, but they are typically very tall so that they can house large quantities of bulk material. A silo has an access point on the top through which new material can be inserted, and then an exit valve on the bottom where material can leave using gravity, an auger, or even a pneumatic conveying system. Most silos are built with a cone shape on the bottom to make it easier to control the flow of material as it leaves and is sent onto a belt or into a pneumatic system. If the bulk material handling system uses a pneumatic conveyor, the conveyor tube can be attached directly to the lower portion of the silo. In large industrial settings where high volumes of material are stored and processed, a series of silos may all be integrated into the same system.
A silo can be built using a variety of materials, but the most common type is built using large sheets of steel that are ribbed on the inside to prevent material from sticking and building up on the walls over a long period of time. A silo can also be mounted on a raised frame with a high enough clearance that a dump truck can park beneath it and quickly accept a load. Dry bulk materials like gravel, coal, sand, cement, woodchips, and sawdust can all be stored in a silo. Flat-bottom silos are used for very high volume bulk storage and are fitted with some kind of mechanical or pneumatic reclaiming equipment to help slowly empty the silo. With a silo or series of silos on site, an industrial facility can securely store a very high volume of bulk materials for an extended period of time without compromising the quality of the material particles.
The term “air handling equipment” refers broadly to those machines and systems that regulate and circulate air. Air handlers that are important to bulk material handling include: blowers, dust collectors and vacuum cleaners.
Blowers are important because they can both dry bulk goods and help transport materials on a pneumatic conveyors. The two main types of blowers used in bulk material handling are axial blowers and centrifugal blowers. Dust collectors tend to very real issue in bulk material handling that is dust accumulation from fine particles. Often, these particles can be harmful if ingested, so it’s doubly important that they be removed from the air. Dust collectors do this by filtering the air. They can stand alone or they can be integrated into pneumatic conveying systems and equipment like material bins and bulk bag unloaders. Finally, vacuum cleaners use suction to remove contaminants like dirt, dust, waste and refuse from the environment and air. They can even be equipped with HEPA filters.
These are just a few examples of air handling equipment. Remember, air handling equipment is extremely diverse and can be customized to accommodate any setting or regulatory requirement. Learn how it can work for you by contacting a reputable manufacturer.
Blowers are devices with a series of spinning blades that are used to generate airflow in a variety of applications. Blowers are important to almost all bulk handling systems because they can be used not only with dry bulk goods but also to power pneumatic conveyors by creating pressure changes for material transfer. An appropriately sized blower can be used in a pneumatic conveyor (large or small) to transport materials through a bulk handling system. High velocity fans or high-pressure blowers are used in bulk material handling facilities to dry materials before they are packaged or stored. High-pressure blowers can also be used to discharge materials at an optimal rate.
Blowers for bulk material handling systems come in two main types: axial blowers and centrifugal blowers. Axial blowers are built with several curved blades that spin on an axis at high speeds. The circular motion of the curved blades creates an imbalance in the surrounding air pressure. This is what causes airflow and allows for transfer in some pneumatic conveyors. A centrifugal blower, also known as a radial blower, is another broad category of blowers that creates airflow in a similar way. However, centrifugal blowers use a different mechanism to create an imbalance in the air pressure. The blades actually spin forward within an enclosure (annular housing). This rapid forward motion in a confined space causes air to be sucked into the housing. The air is pressurized when it leaves the blower and is discharged through a chute or tube. Axial and radial blowers can operate at the same RPM, but the centrifugal force of radial blowers makes them capable of producing higher-pressure flow. These blowers can be mounted to pull air into a tube from the side, which is perfect in bulk handling systems where material must pass through sharp angles and curves in the pipe.
Blowers can be used to handle both wet and dry bulk material solids. Of course, wet bulk materials usually weigh more due to their moisture content, so higher pressure air flow will be required to move them through a pneumatic system. One interesting and unique application of blowers is in the landscaping industry. Truck blowers can be mounted onto a truck or trailer’s storage tank and fitted with a long, wide hose. This type of blower can be used to blow mulch into gardens. A tool like this gives landscapers a quick and easy way to mulch flowerbeds and other areas on a property. For loading and unloading of bulk materials into or out of tanks, blowers can be used to create enough of a pressurized air flow to move materials between point A and point B in a system.
A simple blower may also be used to dry bulk materials as they move along on a conveyor belt. The air does not need to be highly pressurized in this case, and it may be heated slightly or kept at room temperature to speed up the drying process. Because so many different industries handle materials in bulk at some point during their production process, blowers are highly sought after by manufacturers around the world. Most blower manufacturers are able to consult with their customers to offer the best possible blower for an existing bulk material handling system. Considerations like speed, particle density, volume, etc. are all very important when selecting the right blower for an application. In some cases, manufacturers create entire bulk material handling systems, so they know exactly which blowers will be best in a particular facility. From plastics to chemical handling to food processing and beyond, most industries would not be able to handle bulk materials efficiently without blowers.
In any dry bulk material handling operation, dust can be a major problem. Fine particles can create a lot of dust when they are being handled, and since some materials are harmful when ingested, this can be very dangerous to anyone working in the area. Not only can the dust be harmful, but it can create a very dirty environment where cleanliness standards are impossible to maintain. To reduce the negative effects of dust, dust collection units are installed and activated while materials are being handled.
In most pneumatic conveying systems, dust filtration units are integrated into the system at strategic points such as the opening to bins, hoppers, and silos. These filters pull in dust and remove it from the surrounding area, purifying the air during the handling process. From time to time the dust collector needs to be emptied manually or the filter will become clogged because it collects so many loose particles in the air.
Dust collectors are often built into bulk bag unloaders, material bins and other types of equipment. Filters in multiple locations of a bulk handling system can be connected through a series of ducts to empty their contents into one central bin. Some of these units must be turned on manually, while others are activated automatically as soon as the handling conveyor is running.
Besides the obvious concerns of harm to workers and cloudy air, many industries also run the risk of being the cause of pollution. Some bulk materials can be harmful to the environment if handled incorrectly, so many industries have regulatory boards or bylaws in place to enforce the use of air pollution control systems. Facilities that do not use these systems can be charged and run the risk of doing serious damage to the environment.
Vacuum cleaners are cleaning machines that use suction to collect dirt, dust, waste products from industrial processes, and other kinds of debris for disposal, recycling, or reuse. In many bulk material handling settings, some materials are lost during processing or transfer. An industrial vacuum cleaner can be used to clean up these materials and even reclaim them for processing at another time. Excess bulk solids can build up quickly in a busy industrial facility, so a strong high-capacity vacuum cleaner is the best way to keep things clean. Vacuuming also eliminates dust and other harmful toxins that may be present in the air and hazardous to human health. Industrial vacuums come in many types and can be configured to almost any type of media; from wet to dry bulk materials and more. In some cases where contamination is not a concern, these materials can be gathered up and entered into the bulk material handling system again. This reduces waste and improves the overall efficiency of the process. More advanced industrial vacuums are built with HEPA filters so that both large and small particles can be removed from a facility.
Essentially, a vacuum is an area from which air has been removed. This drastic reduction in pressure causes the more highly pressurized air surrounding the vacuum to rush into it with great force. Vacuum cleaners are able to create an artificial vacuum with low air pressure in order to collect debris. All vacuums cleaners are configured differently and some create lower pressure than others. However, in all vacuum cleaners the same basic principle applies and dust or dirt is quickly drawn in.
There are several different types of industrial vacuum cleaners that can be used in bulk material handling systems: continuous bagging vacuum cleaners, air powered vacuum cleaners, and continuous duty vacuum cleaners. Continuous bagging vacuum cleaners are designed to deal with dusty debris. These systems are equipped with closed bags that capture and confine dust so that it does not spread through a facility. The vacuum can run continuously to capture particles as bulk materials are being conveyed or processed. Air powered vacuum cleaners make use of forced air to gather materials. The do not require electricity or generate heat, so they are very safe to operate in a facility that handles hazardous materials. Finally, continuous duty vacuum cleaners are built to work around the clock in tough environments where constant vacuuming is a necessity. Continuous duty vacuums are usually used when material recovery is a priority since they can operate for as long as all of the other equipment is running.
In small to medium sized bulk material handling operations, industrial vacuum cleaners may be portable so that they can be moved throughout the facility as needed. In larger bulk material handling facilities, the vacuum may be placed in a stationary position somewhere in the production line, or there may be several vacuum units to capture all of the dust and debris.
Central vacuum cleaning systems are also an option for some bulk material handling facilities. These systems have a central chamber that is connected to various outlets in the facility via ductwork. Hoses can be moved around and inserted into the outlets which then transport the debris to the chamber. The container of a central vacuum system can be emptied periodically and stored out of sight for a more efficient use of space.