Coal production technology and technology, coal washing technology and technology

The coal preparation plant consists of the following main processes

Generally speaking, the coal preparation plant consists of the following main processes:

(1) Raw coal preparation: including raw coal receiving, storage, crushing and screening.

(2) Raw coal separation: At present, the main separation process in China is jigging-flotation combined process; Dense medium-flotation combined process; Jigging-dense medium-flotation combined process; Dense medium cyclone separation process for lump coal and dense medium cyclone for final coal: In addition, there are single jigging and single dense medium processes.

(3) Product dehydration: including lump coal and fine coal dehydration, flotation clean coal dehydration and slime dehydration.

(4) product drying: coal is dried by heat energy, which is generally used in cold areas.

(5) Coal slurry treatment.

Main process of coal preparation

The role of coal washing:

(1) Improve coal quality and reduce pollutant emissions from coal combustion.

Coal washing can remove 50%-80% ash and 30%-40% total sulfur (or 60%-80% inorganic sulfur) from coal. Coal washing can effectively reduce the emissions of soot, sulfur dioxide and nitrogen oxides. Washing 65.438+100 million tons of power coal can generally reduce 600,000-700,000 tons of tSO2 emissions and remove 654.38+0.68 tons of gangue.

(2) Improve coal utilization efficiency and save energy.

The improvement of coal quality will significantly improve coal utilization efficiency. Studies have shown that the ash content of coking coal is reduced by 1%, the consumption of ironmaking coke is reduced by 2.66%, and the utilization coefficient of ironmaking blast furnace can be increased by 3.99%. Using washed anthracite in synthetic ammonia production can save coal by 20%; When the ash content of coal for power generation increases by 65438 0%, the calorific value decreases by 200 ~ 360 J/g, and the standard coal consumption per kWh increases by 2 ~ 5g. The thermal efficiency of industrial boilers and kilns burning coal can be improved by 3% ~ 8%;

(3) Optimize product structure and improve product competitiveness.

Developing coal washing is conducive to the transformation of coal products from single structure and low quality to multi-variety and high quality, and to realize high quality products. There are many coal consumers in China, and the requirements for coal quality and variety are constantly improving. Some cities require that the sulfur content of coal is less than 0.5% and the ash content is less than 10%. If coal preparation is not developed, it will not meet the market requirements.

④ Reduce the waste of transportation capacity.

Because the coal-producing areas in China are far away from the economically developed areas that use a lot of coal, the transportation volume of coal is large and the transportation distance is long, with an average transportation distance of about 600 kilometers. A large number of impurities can be removed after coal washing, and the transportation capacity can be saved by washing raw coal1000 mt.

Usually, the washing methods include jigging process, dense medium process and air coal preparation.

Of course, with the progress of science and technology and the development of the times, some special washing processes that are being tackled or put into production will be further developed and replaced by traditional processes.