Views: 7963 Author: Site Editor Publish Time: 2016-11-30 Origin: Site
I. Project overview
Date of signing: 2016-11-30
Processing materials: limestone, raw coal
Processing capacity: activated calcium oxide 400t/d, pulverized coal 200t /d
Equipment configuration: lime rotary kiln, rotary cooling machine, coal mill, bag dust collector, lime storage bin, lime ball mill, other supporting equipment and electrical control system
In November 2016, due to business needs, we ordered a full set of activated calcium oxide production equipment with a daily output of 400 tons, and equipped with a daily production of 200 tons of pulverized coal and a daily production of 40 tons of calcium oxide mill. All the program design, equipment manufacturing, installation and commissioning of the production line are undertaken by Zheng Mining machinery, and it was officially put into production in October 2017.
The final product of the production line is calcium oxide powder, which integrates active calcium calcination, pulverized coal preparation, calcium oxide cooling, storage, grinding and waste gas treatment. The unit energy consumption is less than 1150kCal/kg. The cooling machine temperature of the product is ambient temperature +60℃, and the exhaust emission concentration is less than or equal to 30 mg/Nm3. Environmental protection and energy saving.
II. Solution
This project is a total contract project of limestone production line, which mainly provides and implements limestone calcination, pulverized coal preparation, activated calcium cooling storage, activated calcium grinding, tail gas purification and other programs in the production process of active calcium oxide:
1) Limestone is calcined by professional lime rotary kiln. During production, the limestone in the silo enters the kiln through the kiln tail and rolls towards the kiln head with the rotation of the kiln barrel. During the movement, the limestone contacts with the high-temperature gas coming from the kiln head for heat exchange, and is calcined into active calcium oxide after the preheating and decomposition process. The production line of this scheme has simple structure, uniform heating of materials, low production and overburning rate, and stable quality.
2) Pulverized coal preparation system. The pulverized coal preparation system is set in the kiln head, which is a wind-swept ball mill system. The raw coal is dried by the hot air from the cooling machine, and the finished product is taken out of the mill by the hot air and collected by the cloth bag dust collector into the pulverized coal bin for use by the multi-air channel burner at the kiln head. The scheme has the advantages of compact process flow, short conveying distance of pulverized coal, saving land area, recovering and utilizing heat energy after cooling by calcium oxide and saving energy.
3) Cooling and storage of active calcium oxide. The active calcium oxide products enter the single barrel cooler for cooling after the kiln, from the kiln cooling 900℃ to the ambient temperature plus 60℃, the cooling efficiency is high, hot air into the kiln, into the grinding auxiliary combustion and raw coal drying. The active calcium oxide from the cooling machine is transported to the bin by the bucket elevator.
4) Calcium oxide powder is prepared by grinding active calcium oxide powder and stored in the warehouse. The scheme is to add a ball mill between the two storage bins. The bulk of active calcium oxide is removed from the bin and directly into the ball mill for grinding. After grinding, the calcium oxide powder is transferred into the elevator for storage. The process is simple and applicable. Compared with the ordinary grinding system, it saves a lot of conveying and selecting equipment and saves investment.
5) kiln tail gas treatment. The exhaust gas from the kiln is first cleaned by the cyclone dust collector, and then filtered by the bag dust collector twice. The clean air is discharged into the atmosphere by the dust collector centrifugal fan. After being filtered by the bag dust collector, the dust content in the gas is less than 30mg/Nm3, which meets the requirements of environmental protection.
III. Project site
