Compared with traditional reinforced concrete silos, steel silos have the advantages of short construction period, low investment, and low maintenance costs. Therefore, steel silos are becoming more and more popular nowadays. When the storage capacity is in the range of 5,000 m3 to 50,000m3, it is especially suitable for steel silos.

Powdery materials stored in large steel silos are often affected by surface energy during storage. The closer the powder is, the larger the adsorption ability is. The adsorption ability of powders in steel silos is greatly influenced by the confinement of silo walls and the pressure of powders themselves. During actual production, due to the effect of moisture content, the powder is inevitable to have the phenomena such as compaction, hardening and stickiness, resulting in substantial waste of resources. Therefore, it is crucial for the material to have a good discharging system of the steel silo.

FLYER Steel Silo Discharging System

One of the advantages of the FLYER steel silo is that the discharging system is very well designed with high emptying rate.

The emptying rate of steel silo refers to the percentage of the unloaded material from the silo and the total material. The emptying rate directly reflects the practical quality and performance of the steel silo. It is the main performance index of the steel silo. When the discharging situation of steel silo goes deteriorated, the deposit of the stored material in the silo increases reversely. The material deposit and slow speed of the discharging can make effective volume reduction and cause low emptying rate. The emptying rate is low to not only make the steel silo play no good discharging effect, but also result in reducing the economic benefit.

How to get rid of the discharging difficulty of large steel silo?

The FLYER adopts the measures as follows:

Multi-point Discharging

Steel silo, especially large steel silo, is directly unloaded of the material from its middle part of the inverted cone bottom, so the material at edge of the silo is always left there and form the so called dead zone. This is the reason that the emptying rate of the silo is greatly reduced. At present, the conventional technology of construction of steel silo popularly cannot be used to solve the serious problem of discharging. At the period of after-completion of the silo, it is okay. But with the extension of time the discharging, the problem is getting worse and worse. For example, a company’s fly ash silo (30 thousand tons and 31m Dia.) has to be unloaded from only 4m Dia. of discharging space when the problem is serious. The rest parts are deposited as dead material and material dead zone in the silo. Afterwards, the silo is utterly blocked and cannot play the discharging work. When clearance, we have found out that its repose angle has up to 70°to 90°, the discharging system has completely lost performance.

We are sure to say that the bigger the storage tonnage of powder material, the lower the emptying rate is. This is decided by the bottom area and storage pressure of the silo. The discharging technology of existing large steel silo is mostly gas transmission, tube homogenization. But the above technology is only suitable for medium powder steel silo and cannot be as the leading discharging equipment of large steel silo. Due to the large steel silo is huge in storage, so the material at the bottom of the powder silo bears under enormous pressure from the upper part of powder material, its density increases relatively. Reaching its certain limit, the powder will agglomerate, which leads to all out the discharging difficulty.

To solve this problem, our FLYER Company has designed out a more environmentally and friendly multi-point discharging technology. The steel silo material in the silo applies multi-point method, which have obvious advantages. First of all, the method has big discharging angle, whose strength combines with gravity. So the discharging process is smooth, its emptying rate is high. Even if long-term storage, it can still ensure the material to be unloaded normally. Secondly, through the supplying of Roots blower, the fluidization rods convey air outwards continuously, the material is always in fluidized state to prevent stickiness and hardening phenomenon. Finally, because of the multi-point discharging, so when some part fails, the material can be temporarily unloaded from the other areas without affecting the normal work. At the same time, the discharging points are arranged reasonably, which provides convenient maintenance for the future.

In the powdery storage industry, with the application and development of science and technology, the method is the ultimate solution to the discharging difficulty of large steel silo. The development of any technology needs time to verify itself. With the help of it, the best emptying rate has reached 98%, which creates great economic benefits to the enterprises.

Moisture Proof Measures

The high moisture content of powder material itself is prone to result in the degradation or failure of the fluidization performance of the material. In this regard, the users should strictly control the moisture content of material before lowering the moisture rate of the material to the minimum. The drier the material is, the better fluidization is. If the cement foundation at the bottom of the silo layer is not completely dry without taking effective measures, the material at the bottom of the silo will become damp and its humidity will also increase, which will cause the material to get into blocks. The situation is going to cause the discharging difficulty. In addition, some users start to use the silo before its cone is dry, so the implementation of moisture proof measures of the bottom of the silo is particularly critical. Our company has decided to paint surface coating to as necessary waterproof material to improve the bottom dryness. The surface of moisture proof layer is smooth and clean to help convey material circulation.

As s new generation of large steel silo, combined with international advanced technology it is a combination of fail and success of all series of steel silos, which completely solve the discharging difficulty of powdery material in a large storage silo. Single silo can store 10,000-100,000 tons of various powder and granular materials, whose emptying rate can reach 95%-98%. It is the ideal storage equipment of powdery material for manufacture enterprises.

What Is Ventilation System?

Ventilation is one of important means to guarantee the material’s safe storage in steel silo. A ventilation system refers to a series of devices loaded on the steel silo help achieve the purpose of ventilation.

Ventilation is beneficial to the cooling and dampening of materials stored in the steel silo. It balances the temperature difference between the inside and outside of the steel silo, inhibits the growth of pests and microorganisms, and prevents moisture transfer and material deterioration.

Venting the steel silo not only accelerates the directional flow of air in the silo, but also prevents condensation due to large temperature differences between the inside and outside of the silo. At the same time, this can adjust the temperature of the roof space, dissipate the upper layer and the surface layer of damp heat, and prevent the upper layer and surface materials from being affected by high temperature, thereby achieving the purpose of balancing the temperature and humidity.

Composition of Ventilation System

Natural ventilation and mechanical ventilation are two ventilation methods we usually use.

Natural ventilation uses the heat pressure of air and the wind pressure caused by wind to realize gas exchange between inside and outside of the warehouse. However, its efficiency is low, and it is restricted by weather and geographical conditions, so its application area is narrow.

Most steel silos adopt mechanical ventilation. Ventilation systems used for mechanical ventilation typically include components such as fans, ventilation ducts, and ventilation floors.

The ventilator is set at the bottom of the steel silo, and dried air (or cooled gas) from outside is introduced into the ventilation groove (or ventilation cage, ventilation pipe, etc.) through the ventilation duct, so that the diffused gas is continuously exchanged with the hot and humid air between the materials in the silo. At the same time, under the synergistic action of the axial-flow fan (or natural ventilation hole) on the top of the warehouse, the hot and humid air on the surface of the material in the warehouse can be discharged in time.

Different Silos Use Different Ventilation Systems

Generally speaking, the ventilation effect of steel silos depends on two points: one is the designed ventilation volume and air pressure; the other is the ventilation system. Common ventilation systems are: groove type, ground cage, single-pipe ventilation, multi-pipe ventilation, radial ventilation, vertical ventilation, Non-duct ventilation, etc.

Ventilation Systems for Hoppers

Annular Air Ventilation

This system opens holes in the discharge cone and ventilates the grain stack in the bin through a number of ports with ventilation panels. This ventilation system is simple to install, easy to use and maintain, and has a small investment. The shortcoming is that the ventilation section is small and can only be partially ventilated, so the ventilation cooling effect is not obvious.

Ground Channel Ventilation on Backfill Slope in Hopper

This ventilation system needs to set up a groove on the backfill slope of the hopper base and lay ventilation sieve plates at the top of the groove to make it flush with the backfill surface. The number of air ducts is related to the diameter of silos. The larger the silo diameter, the more air ducts need to be arranged. Compared with the annular ventilation system, the investment of this ventilation mode is not much increased, but the ventilation effect is very obvious, so it is widely used.

Ventilation Systems for Flat Bottom Silos

There are two kinds of ventilation in flat bottom silos: one is to set up ventilation grooves in the foundation, and lay ventilation sieve boards with certain opening rate and supporting strength on the groove; the other is to lay ground cages on the silo foundation (after calculation of supporting strength).

Generally speaking, the ventilation mode of flat silo has good ventilation effect, and the air ducts are easy to be arranged symmetrically. It can achieve a larger ventilation cross-section area, so it is easy to uniformly distribute the air volume. Relatively speaking, investment in civil infrastructure and equipment such as ventilation sieve board is slightly larger.

Conclusion

There are many ventilation systems for steel silos, each has its pros and cons. A ventilation system should be selected base on the storage characteristics, storage period, quality requirement of the storing material and other elements. We need to compare their ventilation performance and cost, and take into account the automation level of mechanical equipment, production efficiency, geological conditions and so on before making the decision.

Steel silos are the most popular storage medium in recent years. Large steel silos can be used to store various industrial and agricultural products such as grain, cement, fly ash and mineral materials, thus meeting the storage needs of most enterprises in modern society.

Adavantages in Cement Storage

The steel silo is a cylindrical storage warehouse made of galvanized coils. Steel silos can also be divided into spiral steel silos and assembled steel silos. The structural principle of the steel silo is very different from the traditional warehouse. Taking cement storage silo as an example, steel silos can solve the following cement storage problems compared to traditional warehouses:

Our steel silo can solve the technical problem of cement cementation and physical index degradation caused by temperature difference and moisture gas in the steel warehouse wall. By installing a temperature control system, the steel silo can effectively control the temperature inside the silo, while ensuring that the physical indexes of the cement in the steel silo remain unchanged.

Our steel silos can solve the problem of water inflow and leakage of cement at the bottom of the storehouse. Our steel silo is made of polymer waterproof material for secondary reinforcement of the bottom of the steel silo. The upper and the bottom of the silo warehouse are made of corrosion-resistant waterproof material as the waterproof barrier. The concrete used in the steel silo foundation and the bottom of the reservoir are all waterproof and anti-seepage concrete.

Controllable prevention and control scope of this design: waterproof grade: grade one; leak-proof grade: 1-30,000 tons of steel silo is between P8-P12, and 5-200,000 tons of steel silo is between P12.

Our steel silos can solve the problem of complete cement discharge. The input and output system installed in our steel silos ensures that the steel silos can be discharged on demand and on time. It satisfies users’ demand for unblocked discharge and full discharge. The discharge rate of 10,000-30,000 tons of steel silos is above 95%.

Advantages in Grain Storage

At the same time, steel silos are the best way to store grain. Thanks to the installation of the temperature measuring device, once the temperature of the grain in the silo changes, we can immediately find out, so that appropriate temperature control measures can be taken to achieve long-term and safe grain storage.

The new steel silos are provided with mechanical ventilation and ventilation ducts at the bottom of the silo. Ventilation with mobile fans is an effective measure to achieve safe grain storage. The use of mobile cooling ventilation can also keep food at low temperature 5~15 degrees. Steel silos can protect grain from external influences and reduce its post-natal losses, which make it the best method for bulk grain storage.

About Us

Anyang Flyer Steel Silo Engineering Co., Ltd is a professional steel silo manufacturer. We design and build various steel silos for both enterprises and individual users. If you have any thoughts on silo storage, please feel free to contact us!

Grain silo is widely used in the grain industry. You can find them in many grain and oil processing plants and grain and oil sales companies.

The capacities of grain silo should be determined by the quantity and variety of grain. There are many factors we should take into account when choosing a grain silo.

How to Decide the Capacity of the Grain Silo?

For large grain and oil processing plants with output of more than 2000 tons, we usually need to build grain silos with capacity of 50,000-80,000 tons. For soybean processing enterprises, because of the simplicity of soybean varieties, enterprises can consider building grain silos with capacity of 10,000-15,000 tons, which is more economical.

For large-scale deep processing enterprises such as corn and starch processing, it is also recommended to choose such large silos because of their large daily processing capacity.

Medium-sized grain and oil processing plants and corn processing enterprises can choose a single steel silo with a storage capacity of about 5000-7500 tons.

For flour processing enterprises, the same standard as grain and oil processing plants can be used to select wheat storage silos, and the capacity of wheat silos should be determined according to daily output. Different from soybean, wheat varieties are more abundant. In order to store different varieties of wheat separately, several steel silos should be constructed. The capacity of a single steel silo is preferably 1000-2000 tons.

For malt and beer processing industry, the capacity of single storage silo should be between 1000 tons and 1500 tons.

For feed processing industry, a single storage silo with capacity between 1000tons and 3000tons is appropriate.

In the field of rice processing, the storage capacity of most rice storage silos is more than 1000 tons.

Small silos installed in trucks for grain transportation are usually hopper bottom silos with small diameters and no more than 500 tons of volume, so that vehicles can directly load grain under the steel silos.

For grain ports and terminals. As a transit point for grain, grain ports have short transportation cycle and large capacity. At present, the storage capacity of China’s coastal ports is mostly 2 million tons, with a single silo capacity between 5000 and 15000 tons.

How to Choose a Proper Grain Silo?

Choosing the right silos is the primary task of grain storage. Our steel silos have the functions of moisture-proof, pest control and rodent control, and is convenient for the input and output of grain. The silo is very airtight and therefore suitable for use with pesticides.

Flyer offers a wide range of galvanized steel silos for grain storage, and provides complete storage solutions and installation equipment for agricultural markets all over the world. Through decades of experience in the design and construction of steel silos, Flyer grain storage silos provide commercial users with the best built-in value in the product life cycle.

Our experienced team of engineers will provide you with professional design from loading, storage to unloading according to your specific requirements. Moreover, all our designs, including preliminary design and architectural design, are free.

In short, the determination of the diameter and height of grain silos and the method of input and output need to take into account many factors. Finally, silos must match the functions you need, otherwise you will not be able to maximize your economic benefits.

Grian silos are built to store various crops and foods. To properly store wheat with grain silos, we must first know its storage characteristics.

Wheat storage characteristics

Strong moisture absorption capacity

The seed coat of wheat is thin, the inner structure is loose, so its moisture absorption capacity is strong.

Long after-ripening period

The after-ripening period of wheat is long. The after-ripening period of different wheat varieties is also different. The ripening period of most varieties ranges from two weeks to two months. The quality of wheat with suitable moisture content will be improved after ripening, which will make it easier to preserve.

High temperature resistance

Wheat has strong heat resistance. According to the experiment, wheat with 17% moisture content will not decrease its enzyme activity and germination ability when it is dried at less than 46 ℃. The quality of ground wheat flour is not reduced, but improved. This provides a basis for wheat to use high temperature drying or high temperature insecticidal.

Good storability

The greatest advantage of wheat is its good storability. The respiration of after-ripened wheat is weaker than that of other cereals. Under normal conditions, wheat with water content within the standard (12.5%) can be stored at room temperature for 3 to 5 years or at low temperature (15 ℃) for 5 to 8 years. At the same time, its edible quality will not change significantly.

Susceptible to insect pests

Wheat is a food with poor resistance to insects and high rates of infection. In addition to a small number of legume-specific insect species, wheat can be infested by almost all stored grain pests, among which maize weevil and the Angoumois grain moth are the most harmful ones.

The ripening, harvesting and storage of wheat are all in the summer, which is the breeding and growing period of pests. The temperature inside the silo after the wheat has just been put into storage is high, and in the case of rainy weather, it is very prone to pests.

Problems needing attention in wheat storage

Strict Moisture Content Control

Because of the strong moisture absorption ability of wheat, we should pay attention to rainproof and moisture-proof during the wheat storage. We should make full use of the high temperature conditions in summer after wheat harvest to expose it to the sun, control the moisture content of wheat below 12.5%, and then store it in grain silo. After the wheat is put into storage, measures should be taken to prevent moisture, and attention should be paid to the stratification of water that may be caused during the after-ripening period.

Put wheat into grain silo when it is still warm

By sun exposure, the water content in wheat can be reduced. At the same time, in the process of exposure and storage, the effect of high temperature insecticidal and bacteria can be achieved. And for newly harvested wheat, high temperature can promote the completion of the after-ripening process. Due to the reduced water content and the amount of bacteria, the respiration intensity of wheat is greatly reduced, allowing it to be stored safely for a longer time.

Store wheat in low temperature and air-tight circumstance

Although wheat can withstand high temperature, its quality will also reduce if continuously stored at high temperature. Therefore, when autumn comes, the grain silo that stores wheat should be ventilated naturally or mechanically to fully dissipate heat, and sealed before spring to maintain the low temperature circumstance in the silo.

Why Choose Us

Anyang Flyer Steel Silo Engineering Co., Ltd has rich experience in grain silo projects. We can build high quality galvanized grain silos in various capacities. The grain silo we built is equipped with a variety of ancillary equipment, including electronic temperature measurement systems, ventilation systems, and automated operating systems. These silos will perfectly fit your requirement for wheat storage. Send your inquiry now!

Steel silos can be used as grain silos to store many varieties of grains such as rice, wheat, bean, and corn.

Rice is a staple food for people in East Asia, so the rice growing and processing industry is very prosperous in these countries. And a very important link in the rice industry is the Rice Storage. What are the storage characteristics of rice? And how do we store it correctly?

Rice Storage Characteristics

The hard glume of rice can protect the grain and resist the influence of insect pest and temperature and humidity. Therefore, rice is easier to store and maintain than ordinary grain. However, rice is easy to germinate and is not resistant to high temperatures, which is a place that requires special attention during storage.

Most rice varieties (such as japonica rice) have no post-maturing period, they are physiologically mature at the time of harvest and have germination ability. Moreover, the amount of water absorption required for germination of rice is rather low. Therefore, if the rice is continuously exposed to rainy weather during harvest, causing it to fail to harvest, thresh and sun-dry in time, the rice will germinate in the field.

Rice in storage is also prone to germination during condensation, moisture, or rain. If the rice is not threshed or sun-dried in time, it will easily turn yellow in the moisture. The quality and storage stability of the rice after germination and yellowing will be greatly reduced.

Rice is not resistant to high temperatures. The rice stored through a summer would likely become obsolete. The rice that is exposed to the sun, or the rice that suddenly catches cold after exposure, is prone to cracks on the grain surface.

If the temperature drops soon after the newly harvested rice is put into storage, the surface of the rice will tend to dew, which will increase the moisture content of the surface grain and is not conducive to storage. At this time, we should promptly reduce the moisture content of the surface grain.

Rice storage method

Guarantee the quality of rice entering the steel silo:

Rice with large water content, high impurities, and imperfect grain, is easy to mildew, and can not be stored for a long time. Therefore, improving the quality of the rice is the key to its safe storage.

The water content standard of rice should be decided according to varieties, seasons, regions, and climatic conditions. Generally, the moisture standard of indica rice is 13% or less, and that of japonica rice is 14% or less. The less impurities and imperfect grains in the rice, the better. If the rice entering the silo has large moisture content and impurities, it should be stored in grades, aired or dried in time, and screened or air-selected to remove impurities.

Timely ventilation:

The newly harvested rice has vigorous respiration and high grain temperature and moisture content. It should be ventilated at appropriate times to reduce its temperature and moisture.

Especially in the autumn, the temperature difference between the inside and outside of the rice heap becomes larger. At this time, the ventilation should be performed more frequently, and we should stir the rice heap to dissipate the damp heat in the grain pile to prevent condensation. Mechanical ventilation is preferred if conditions permit.

Low temperature and air-tight:

For rice stored in steel silos, in winter, it is necessary to make full use of the cold and dry weather to ventilate, so that the temperature of the rice can be lowered to below 10 degrees Celsius and the moisture content can be reduced to safety standards. Then seal the silo before the temperature rises in the spring, so that the rice can be safely stored during summer.

The forms of coal storage are mainly as follows:

1) Open coal storage yard, also called the open-pit coal storage yard, is a form of coal storage widely used by traditional coal enterprises in China and has been basically eliminated;
2) Spherical coal storage yard, also known as hemispherical coal storage bin, developed from the structure of dry coal shed, is a fully enclosed coal storage mode, which is one of the main coal storage forms adopted by coal enterprises at present;
3) Cylindrical coal storage silo, or coal storage silo, is also a fully enclosed coal storage mode, which is widely used in coal enterprises at present.

With the continuous implementation of the national sustainable development strategy, the environmental protection awareness of coal production enterprises has gradually improved, and the mode of coal storage has gradually changed from semi-closed to closed. Therefore, the spherical coal storage and coal storage silos have developed rapidly in recent years and have been widely applied.

Open coal storage yard

Open coal yard has less investment, mature technology, higher flexibility in stacking different kinds of coal, and can use the size and shape of land to determine the height and quantity of coal storage, generally in rectangle shape.

The construction of the open coal storage yard is relatively simple. It is only necessary to peel the topsoil layer by 0.8~1m, and compact the gravel at the stripping layer, and then cover the surface with 0.2m coal gangue and compact it, then the storage yard is good to use.

The disadvantage of the open coal storage yard is that the coal storage loss is large, the coal storage is easy to be lost and the coal is easy to spontaneously ignite. If the corresponding environmental protection measures are not taken, it will also pollute the surrounding environment of the coal storage yard. Moreover, the occupied land area is large and the land utilization rate is low. With the continuous attention of the society to environmental protection problems, the form of coal storage has basically been eliminated.

Hemispherical coal storage bin

Spherical coal storage yard is also known as hemispherical coal storage bin, generally using spherical reticulated shell at the top and concrete pouring at the bottom. This kind of coal storage process is different from the traditional coal storage yard. Generally, a plurality of hemispherical coal storage bins are often used at the same time, which is commonly referred to as a hemispherical coal storage bin group.

The diameter of a large fully sealed hemispherical ball storage bin is usually above 80m. At present, some storage bins have a diameter of 120m, a stacking height of 30m, and the reserves of a single hemispherical coal storage bin can reach 200,000 tons.

The disadvantage of the hemispherical coal storage bin is that the actual utilization rate of designed reserves is greatly influenced by coal quality. In addition, in order to ensure the timely clean-up of coal storage in spherical coal storage bin, each hemispherical coal storage bin needs to install a set of stacker, reclaimer with a rotating range of 360 degrees, or special loader and other coal storage equipment to ensure the coal storage cycle and system production efficiency.

Coal storage silo

Coal storage silo is a coal storage method developed in the late 50s. When the coal quantity is small, the coal storage silos are arranged in a single line; when the coal quantity is large, the silos will be built into silo groups. The steel coal storage silos are generally steel structures with a cone shell top, a cylindrical silo body, and an inverted cone bottom funnel.

The coal storage silo has a large volume and the land utilization rate is extremely high. When loading, the belt conveyor directly discharges the bulk material into the silo at the top of the silo, or selectively distributes different coal types into different coal storage silos by using a scraper conveyor. When unloading, the bulk material is unloaded to the horizontal belt conveyor through the bottom inverted cone discharge funnel. Then go to the coal blending tray for coal blending.

In order to solve the problem of coal blockage caused by coal freezing in winter in coal storage silo, a carbon fiber heating device is installed under the silo. Through intelligent temperature control system, the temperature of coal storage silo can be controlled steadily.

Conclusion

From the above introduction, it can be seen that the construction cycle of open-pit coal yard is short, the investment is little, but the pollution is serious; the spherical coal yard has achieved the form of fully closed coal storage, but for open-pit coal yard or dry coal shed, the investment is increased and the construction cycle is prolonged; the coal silo covers a small area, the site utilization rate is high, and the environmental protection effect is more obvious. It has become the future development direction of coal storage form to effectively avoid the loss of coal caused by wind and rain and the impact of coal moisture increase and decrease on the belt conveyor system.

For coal storage yards of the same capacity scale, the fully enclosed spherical coal storage yard has the largest investment and the highest operation cost, but it will not cause coal loss; the investment and operation cost of open-pit coal yard is the second; the investment of coal storage silos in parallel is the smallest and the operation and maintenance cost is the lowest; it will not cause the loss of coal and the environmental impact. It is also the best way to store coal in the automatic loading system.

Anyang Flyer Steel Silo supplies coal storage silos in various sizes and capacities. If you have any thoughts on coal storage, please do not hesitate to contact us!