Analysis of Innovative Process Technology for Bulk Material Storage and Delivery

——Qinhuangdao Hongrui Technology Development Co., Ltd.

Preface

With the development of my country's society and economy, the grain processing industry is booming. The concentration of industry is becoming more and more obvious, and the corresponding cost of storage and logistics of raw grain and by-products is also increasing. How to effectively control the cost of warehousing and logistics has become a common thinking and urgent problem in the industry. This article will enumerate and analyze the plans and measures of different grain processing enterprises in warehousing and logistics for reference only.

Method 1: Silo storage;

Auxiliary equipment: bucket elevator, scraper feeding; clearing machine, discharging machine;

Scraper, belt conveyor conveying.

Application: It is widely used in the storage and logistics of raw grains (soybeans, corn, wheat, rice, rapeseed, etc.); the by-product soybean meal, rapeseed meal and soybean hulls of the oil industry have been widely promoted.

Features: small area, high utilization rate of warehouse capacity, low unit construction cost (flat-bottom steel silo<flat-bottom concrete silo<cone-bottom steel silo<cone-bottom concrete steel silo. The cost is roughly 100- 290 yuan/ton.), short construction period, high degree of automation, low operating cost, etc.

Method 2: Storage in a flat warehouse;

Auxiliary equipment: feeding by bucket elevator, scraper or stacker; discharging by forklift and grain picker; conveying by belt conveyor.

Application: There are many applications in the storage of bulk materials or by-product packaging bags such as raw grains (soybeans, corn, wheat, rice, rapeseed, etc.), by-products (soy hulls, soybean meal).

Features: large area, low utilization rate of warehouse capacity, low construction cost, low degree of automation, high operating cost, etc.

Method 3: Package storage;

Auxiliary equipment: filling equipment, palletizer, forklift stacking, forklift destacking, belt conveyor (manual loading)

Application: Used in by-products such as soybean hulls, soybean meal, and bran.

Features: large area, low utilization rate of warehouse capacity, low construction cost, low degree of automation, high operating cost, etc.

Common problem 1: Automatic classification, uneven quality of materials out of warehouse

When the material enters the silo from the inlet at the top of the silo, the material will be automatically classified under the combined action of gravity and air resistance. The heavier material particles will be concentrated and pile up near the inlet, which is lighter. The material particles are scattered around. Then the more materials are put into the warehouse, the detailed classification in the warehouse becomes more obvious, and finally there will be a large area of ​​material accumulation area with huge difference in quality. If this situation is not considered to intervene, it will result in quality differences when the materials are discharged, that is, it is possible that the materials that are discharged first are very high-quality materials, and then the materials discharged gradually become inferior. This is very detrimental to the sales of bulk materials.

　　Common problem 2: agglomeration, arching, wall hanging

　　 Due to the emergence of medium automatic classification, some materials with light weight and small particle size, even some dust and dust, are automatically distributed to the silo near the silo wall. With the increase of materials in the warehouse, different material layers from the warehouse wall to the center of the warehouse will be formed. The material in direct contact is light in weight, small in particle size, and has relatively strong adsorption capacity for water, which is easy to form agglomerates or hang on the wall. In addition, the materials in this area are greatly affected by the changes in the outside temperature due to the contact with the warehouse wall, especially the large temperature difference between day and night in autumn in the northern region. Under the repeated action of temperature difference and moisture, the materials in the silo, especially near the silo wall, will expand and contract continuously, which may eventually form larger agglomerates or form larger binding force and friction between particles. Eventually, the materials in the warehouse will be agglomerated, arched and wall hung.

　　 Ways to solve the above problems:

　　First, formulate strict warehousing procedures, and no warehousing is allowed if the standards are not met;

　　Second, appropriately increase the diameter of the silo to destroy the conditions for arching and bridging of the silo;

　　 Third, change the quantity and distribution of material inlets, so that the materials are evenly placed in the warehouse and distributed evenly;

　　 Fourth, use the silo's in and out equipment to carry out the dumping process, the moisture and heat of the materials in the silo are evenly distributed, and the materials in the silo are evenly stirred.
 
 

1. Clearance machine

working principle

The walking mechanism pushes the screw conveyor with a side opening whose length matches the radius of the silo, and rotates around the slewing support mechanism located in the center of the silo (central discharge port), while the screw conveyor conveys the material to the central discharge port , Realize the clearing function.

Scope of application

It is suitable for clearing the remaining materials in the medium and large flat-bottomed shallow round warehouses and square warehouses after the self-flowing is completed.

Conventional specifications

Application: Shallow round warehouse with a diameter of 10-36 meters and a square warehouse with a span of 36 meters.

Materials: soybean, corn, wheat, rice, rapeseed, etc.

Output: 30tph-400tph

2. Warehouse machine

working principle

The walking mechanism pushes the screw conveyor with a side opening whose length matches the radius of the silo and rotates around the slewing support mechanism located in the center of the silo (the central discharge port), while the screw conveyor conveys the material to the central discharge port , Realize the warehouse function.

Scope of application

It is suitable for small and medium-sized flat-bottomed shallow round warehouses, so that the materials in the warehouse can be discharged out of the warehouse quantitatively and regularly according to the actual production, to ensure the characteristics of the materials to avoid compaction, and the first-in first-out rule is adopted.

Conventional specifications

Application: Shallow round warehouse with a diameter of 8-16 meters.

Materials: bran, soybean hull, soybean meal, rapeseed meal, rice bran meal, etc.

Output: 5tph-100tph.

3. Cone bottom discharge machine

Cone-bottomed cylindrical silo for storing powder and granular materials, half of the cone angle of the bottom of the silo must be greater than the static angle of repose of the material, and the material can flow out of the silo, but some materials have been stored in the silo for too long or other physical and chemical factors , Make the material particles and between the material and the silo bottom plate have a cohesive force (or affinity), so that all the materials can not flow out of the silo, and a part of it remains on the silo bottom, which needs to be cleaned out manually. If the warehouse is cleared manually, people cannot stand on the slope of the warehouse bottom naturally due to the large slope of the cone-bottom warehouse, so the warehouse clearance operation cannot be performed. It is very unsafe to use ropes to suspend manual work, even if it is a springboard. Cone bottom warehouse clearing machine is a clearing equipment designed to adapt to this occasion. Cone bottom warehouse clearing machine does not require manual entry into the warehouse. It has high clearing efficiency, low energy consumption, safety and reliability. The rotation and revolution motor of the clearing machine, reducer They are all set outside the warehouse for easy inspection and maintenance.

working principle

The walking mechanism pushes the screw conveyor with the opening on one side whose length matches the length of the busbar of the cone bottom of the silo, and rotates around the slewing support mechanism located in the center of the silo (central discharge port), while the screw conveyor transports the material to the center The discharge port realizes the function of exiting the warehouse.

Scope of application

The discharge machine is mainly used in cone-bottom cylindrical silos, so that the materials in the silo are discharged quantitatively and regularly according to the actual production, to ensure the characteristics of the materials to avoid compaction, and take the first-in first-out rule.

Conventional specifications

Application: Cone bottom silo with a diameter of no more than 12 meters.

Material: It can form a self-flowing powdery granular material.

Output: 20tph-100tph.

4. Vibration ejector

working principle

It is installed at the bottom of the cone through a soft connection. When the vibrating hopper is working, the internal materials are loosened, and the loose materials flow into the screw conveyor at the bottom.

Scope of application

It is suitable for discharging powder materials from small cone bottom bins.

Process design parameters of bran bin:

1. Conventional single-line production capacity of flour mills: 300 tons/day, 600 tons/day, 750 tons/day, 1000 tons/day;

2. Bran output rate: 20% (coarse bran accounts for 2/3, fine bran accounts for 1/3);

3. Reference bulk density of bran: 0.26 tons/cubic meter;

4. It is assumed that the standard specifications and equipment configuration of the existing conventional bran warehouse are as follows: the warehouse diameter is 4 meters, the reserve is 200 cubic meters, and the supporting GBS scraper (domestic 150,000 yuan/set).

The advantages of adding a flat-bottomed cylindrical silo storage supporting screw unloading machine (refer to the single-line production capacity of 1000 tons/day):

Advantage 1:

　　Compared with production packaging, storage, and filling, saving labor costs;

　　 is packaged and stored with the production. As long as the production is in progress, special packaging personnel must be configured, which has low packaging efficiency and high cost. According to 3 shifts per day, 2 people per shift, 6 daily labors are required per day.

　　Using flat-bottomed silo storage, it is possible to centrally arrange personnel to pack according to the reserves, basically ensuring that two people can complete the packaging tasks for the corresponding production line for one day in one shift.

　　The wages of workers are calculated at 50,000 yuan per year, and this can save 200,000 yuan per year.

Advantage 2:

　　Logistics link, saving costs;

　　 Under the condition of ensuring the stability of the filling, the bran bags that are packed off the line can be directly loaded into the car, eliminating the steps of stacking, stacking and unstacking. Assuming that half of the bran (100t) per day is packaged and directly loaded after warehousing and deployment, the annual cost is 300 days, and the stacking, stacking, and destacking costs are calculated at 5.5 yuan/ton, which can save 165,000 yuan per year.

Advantage 3:

　　 can effectively inhibit the deterioration of bran during storage, and reduce the loss of circulation links.

Through statistical data in the oil industry and soybean meal, the silo storage method can reduce the loss by about 5‰, produce 60,000 tons of bran per year, and save 300 tons of bran per year. The average price of bran is 1,600 yuan/ton. It can save 480,000 yuan every year.

Advantage 4:

　　 Able to adapt to market price fluctuations and guarantee high-priced shipments, an increase of 30 yuan per ton, 30,000 tons (half) of bran sold during the period of high price fluctuations, an annual increase of 900,000 yuan in revenue.

Advantage 5:

　　 can adapt to the technological requirements of bulk transportation of bran, avoiding repeated investment.

　　 In summary, adding flat-bottomed silos can increase revenue by about 1.745 million yuan per year, and increase the construction cost of silos and supporting warehouses by about 3.34 million yuan, and the investment can be recovered within 2 years.

　　It is foreseeable that bulk storage, packaging, direct loading, and bulk transportation of bulk materials will gradually become the trend of material storage, transportation and logistics development in the industry.