Rotary furnace low-order powdered coal pyrolysis upgrading method with coal gas circulation

Abstract

The invention provides a rotary furnace low-order powdered coal pyrolysis upgrading method with coal gas circulation. The rotary furnace low-order powdered coal pyrolysis upgrading method comprises the following steps: heating and drying raw material powdered coal with the granularity less than or equal to 30mm to be 110-280 DEG C in a low-order powdered coal rotary drying system with dust collection, and removing 85% of coal dust with the granularity less than 0.5mm in the powdered coal; feeding the dried coal with the granularity of 0.5-30mm to a downstream rotary pyrolysis system to react at 500-700 DEG C so as to generate upgraded coal and a high-temperature oil gas; feeding the high-temperature upgraded coal to a rotary cooling passivating furnace for primary cooling and medium / low temperature passivation, further cooling by using a spiral cooling machine, spraying water, and discharging out the product; feeding the high-temperature oil gas into an oil gas recycling system, and performing temperature reduction separation, thereby obtaining coal tar, pyrolysis water and pyrolysis coal gas; preheating a part of the pyrolysis coal gas, circulating back to the pyrolysis furnace, and discharging out the rest part of the pyrolysis coal gas.

Description

technical field

[0001] The invention relates to a new process technology for industrialized low-rank pulverized coal pyrolysis and upgrading, in particular to an industrialized technology and equipment using low-rank pulverized coal as raw material and using a rotary furnace for pyrolysis and upgrading, belonging to a new type of coal chemical industry technical field. Background technique

[0002] my country is rich in coal resources, among which low-rank coal accounts for more than 50% of the total coal in my country. However, low-rank coal usually has the characteristics of high oxygen content, high moisture, poor stability and low calorific value, so this type of coal is difficult to be used as a large-scale coal. Industrial gasification feedstocks are mostly used as power fuels in local areas. The pyrolysis upgrading of low-rank coal can change its pore structure to a great extent, reduce its moisture and volatile content, improve its calorific value and thermal stabili...

Examples

Embodiment 1

[0049] 2 tons of Shenfu pulverized coal (0-30mm) are continuously sent to the direct and indirect combined rotary drying furnace, and the flue gas from the 600 ℃ rotary pyrolysis furnace is passed through the jacket as a heat source, and the coal is heated and dried to 250 ℃, The water content is reduced to 0wt%; meanwhile, circulating drying gas at 300°C is introduced into the rotary drying furnace, and under the action of the gradient combined distributor, the coal dust with a particle size of less than 0.5mm and more than 85% in the pulverized coal is removed.

[0050] The drying gas discharged from the rotary drying furnace is entrained with coal dust and water vapor, and enters the drying gas processing unit to separate coal dust, cool down and recycle drying water. The furnace forms a closed-circuit circulation of circulating drying gas.

[0051] The dry coal of 0.5-30mm from the rotary drying furnace enters the rotary pyrolysis furnace. At the same time, the circulating...

Embodiment 2

[0055] 6 tons of Shenfu pulverized coal (0-30mm) are continuously sent to the direct heating rotary drying furnace, and the clean flue gas (O 2 content of 2vol%) as a drying heat source, the coal is heated and dried to 250 ℃, and the water content is reduced to 0wt%; at the same time, under the action of the gradient combined distributor, the coal dust that is less than 0.5mm and more than 85% in the pulverized coal is removed. remove.

[0056] The drying gas discharged from the rotary drying furnace is entrained with coal dust and water vapor, and enters the drying gas processing unit for separation of coal dust, cooling and recycling of drying water. The high-temperature flue gas at the outlet of the furnace jacket is returned to the rotary drying furnace to form a closed-circuit circulation of circulating drying gas.

[0057] The dry coal of 0.5-30mm from the rotary drying furnace enters the rotary pyrolysis furnace. At the same time, the circulating pyrolysis gas from the...

technical field

[0001] The invention relates to a new process technology for industrialized low-rank pulverized coal pyrolysis and upgrading, in particular to an industrialized technology and equipment using low-rank pulverized coal as raw material and using a rotary furnace for pyrolysis and upgrading, belonging to a new type of coal chemical industry technical field. Background technique

[0002] my country is rich in coal resources, among which low-rank coal accounts for more than 50% of the total coal in my country. However, low-rank coal usually has the characteristics of high oxygen content, high moisture, poor stability and low calorific value, so this type of coal is difficult to be used as a large-scale coal. Industrial gasification feedstocks are mostly used as power fuels in local areas. The pyrolysis upgrading of low-rank coal can change its pore structure to a great extent, reduce its moisture and volatile content, improve its calorific value and thermal stabili...

Examples

Embodiment 1

[0049] 2 tons of Shenfu pulverized coal (0-30mm) are continuously sent to the direct and indirect combined rotary drying furnace, and the flue gas from the 600 ℃ rotary pyrolysis furnace is passed through the jacket as a heat source, and the coal is heated and dried to 250 ℃, The water content is reduced to 0wt%; meanwhile, circulating drying gas at 300°C is introduced into the rotary drying furnace, and under the action of the gradient combined distributor, the coal dust with a particle size of less than 0.5mm and more than 85% in the pulverized coal is removed.

[0050] The drying gas discharged from the rotary drying furnace is entrained with coal dust and water vapor, and enters the drying gas processing unit to separate coal dust, cool down and recycle drying water. The furnace forms a closed-circuit circulation of circulating drying gas.

[0051] The dry coal of 0.5-30mm from the rotary drying furnace enters the rotary pyrolysis furnace. At the same time, the circulating...

Embodiment 2

[0055] 6 tons of Shenfu pulverized coal (0-30mm) are continuously sent to the direct heating rotary drying furnace, and the clean flue gas (O 2 content of 2vol%) as a drying heat source, the coal is heated and dried to 250 ℃, and the water content is reduced to 0wt%; at the same time, under the action of the gradient combined distributor, the coal dust that is less than 0.5mm and more than 85% in the pulverized coal is removed. remove.

[0056] The drying gas discharged from the rotary drying furnace is entrained with coal dust and water vapor, and enters the drying gas processing unit for separation of coal dust, cooling and recycling of drying water. The high-temperature flue gas at the outlet of the furnace jacket is returned to the rotary drying furnace to form a closed-circuit circulation of circulating drying gas.

[0057] The dry coal of 0.5-30mm from the rotary drying furnace enters the rotary pyrolysis furnace. At the same time, the circulating pyrolysis gas from the...

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