Annual Production of 50,000 Tons of Pulverized Coal Project (Linyi, Shandong, China)

I. Project overview

Project address: Linyi, Shandong

Production scale: annual production of 50,000 tons of pulverized coal production line

This project includes lifting equipment, storage equipment, metering equipment, grinding equipment, dust collection equipment, coal injection equipment, nitrogen protection equipment and automatic control system. The supply, installation and commissioning of the project are all contracted by Henan Zhengkuang Machinery Co., LTD. After the equipment was sent to the site, our staff stayed at the site and actively followed up, and the installation and commissioning were successfully completed and put into production.

The finished coal powder has uniform particle size and can be fully burned to meet customer needs. The whole system is controlled by negative pressure, running smoothly and without pollution. Since the operation of the equipment, the failure rate is low, which is well received by customers. Main equipment: air sweep mill, dynamic separator, explosion-proof dust collector

Service scope: from raw material storage and transportation, pre-drying, grinding, powder selection, cooling to finished product storage and transportation system, environmental dust collection system, electrical automation control system process design, plant planning, equipment supply, equipment installation and commissioning, after-sales training and a series of technical services.

II. Process flow

Raw coal storage and transportation system

The raw coal with particle size < 35mm and water content < 15% is transported to the raw coal shed by the dump truck, the raw coal stored in the coal shed is loaded into the coal hopper by the loader, the raw coal in the coal hopper is uniformly fed to the bucket elevator by the electromagnetic vibration feeder, the raw coal is lifted by the elevator, and then the belt type ration feeder enters the mill through the double lock air valve.

A bar valve is arranged between the original bunker and the belt type ration feeder. The bar valve can be closed during the maintenance of the speed feeding belt conveyor, which is conducive to the maintenance operation. The belt ration feeder can realize speed regulation function, which is conducive to production operation and management.

Pulverizing system

The raw coal from the raw coal storage and transportation system enters the wind-swept coal mill, and after grinding, the coal powder carries out mass and heat transfer with the hot air of 200℃ ~ 350℃, the water enters the flue gas from the coal, the coal powder is dried by the hot air, and then the coal powder enters the classifier with the air flow, and the selected coarse powder returns to the grinding inside the mill, and the fine powder continues to enter the powder collection system with the air flow through the coal air pipeline.

Blast relief valve and nitrogen protection interface are provided in the hot air inlet pipe and the coal air outlet pipe to protect the safety of equipment and system. By adjusting the frequency converter, the fineness of the powder can be controlled remotely.

Powder collection system

Under the negative pressure of the induced draft fan after the explosion-proof bag dust collector, the qualified fineness of the pulverized coal discharged by the pulverized coal separator enters the explosion-proof bag dust collector through the coal air pipe. After being filtered by the filter bag inside the dust collector, the pulverized coal is captured and falls into the pulverized coal hopper at the lower part of the dust collector. The flue gas filtered and purified by the dust collector is discharged to the atmosphere by the induced draft fan through the chimney. The pulverized coal stored in the pulverized coal hopper is sent to the pulverized coal bin by the star discharger and the screw conveyor.

III. Main equipment

Air swept coal mill 2.2*4.4m

Product usage: Mainly used for the project boiler pulverized coal fuel. The equipment has the characteristics of drying and grinding, reliable operation, continuous operation, large production capacity, high grinding efficiency, and is an ideal equipment for pulverized coal preparation.

Working principle: Qualified raw coal enters the mill through the feeding device, and the hot air enters the mill through the inlet air pipe. With the rotation of the mill barrel, the coal and the hot air exchange in the mill, and the coal is crushed and ground in the mill. At the same time, the fine powder is brought out of the mill through the hot air in the mill and the discharge device.

Dynamic powder separator MD350

Product use: coal mill dynamic separator is mainly suitable for the classification of pulverized coal in the process of pulverized coal manufacturing.

Working principle: Pulverized coal with the gas in the mill, from the lower inlet of the shell into the shell, in the process of rising along the shell, due to the slowing of the airflow speed, a large number of coarse powder deposited, discharged by the shell discharge port. The gas containing a large amount of fine powder forms eddy currents through the fixed air vane and the grid plate of the rotor at a certain Angle, and the material is divided into coarse powder and fine powder by the action of air flow. By this unique structure, the material can be repeated sorting, and each sorting is completed according to a clear balance of forces, that is, a balanced and stable horizontal vortex flow is formed between the rotor and the shell, so that the material stays in the powder selection area for a long time, which is more convenient to ensure the fineness of powder selection, improve the efficiency of powder selection, and improve the output of the entire coal grinding system.

High concentration explosion-proof bag dust collector PPW600-M

IV. Working principle and characteristics:

High concentration explosion-proof bag type dust collector is specially customized dust collection equipment for pulverized coal preparation by Zhengmine machine. It has high dust collection efficiency, suitable for high concentration dust containing gas, and explosion-proof doors are set in each room for high safety.

The dust collector is composed of an ash hopper, an upper box, a middle box, a lower box, etc. The upper, middle and lower boxes are divided chamber structures. When working, the gas containing pulverized coal enters the ash hopper by the inlet air duct, the coarse dust particles directly fall into the bottom of the ash hopper, the fine dust particles enter the middle and lower box with the airflow turning point, the dust accumulation is attached to the outer surface of the filter bag, the filtered gas enters the upper box to a row of air ducts of the net gas collection pipe, and is discharged to the atmosphere by the exhaust fan.

The cleaning process is to cut off the clean air outlet duct of the chamber first, so that the cloth bag of the chamber is in a state of no air flow through (separate chamber stop air cleaning). Then the pulse valve is opened and the compressed air is used to pulse the ash cleaning. The closing time of the cutting valve is enough to ensure that the dust removed from the filter bag after the injection is settled to the ash hopper, avoiding the phenomenon that the dust is collected from the filter bag surface with the air flow to the adjacent filter bag surface, so that the filter bag is cleaned and the exhaust valve, pulse valve and ash unloading valve are automatically controlled by the programmable controller.

V. Live pictures