Coal Gasifier

INTRODUCTION OF SINGLE-STAGE GASIFIER TECHNOLOGY

The technology of single-stage gasifier , with 20mm-60mm bituminous coal or anthracite as fuel, is the gasification technology of a series of chemical reactions working inside gasifier., which consists of oxidization, reduction, pyrolysis and drying. Etc. After the technical disposal with optimized alloction of dust-removing , tar-removing and cooling ,etc., the clean coal gas out of gasifier is supplied to industrial kiln by gas pressure adding and transmission system. Hot coal gas and cold coal gas technology are defined according to requirements of different kilns. The whole system includes coal yard, slag yard, coal lifting system, coal bunker, coal feeding system, air supplying system. single-stage gasifier gasifying system. dust-removing and purifying system, light oil catching and recycling system , auto-control system, gas storage, pressure adding and transmission system.

HOT GAS STATlON OF SINGlE STAGE GASIFIER  

The single stage gasifier is of continuous gas-making and whole water jacket type. Saturated air, which is formed by self-produced 0.294MPa steam and air from blower, is used as gasification agent and comes into gasifier from the bottom check valve. Block coal is broken up and filtrated to size of 25- 50mm or 50 – 80mm.Then the coal is fed into coal bunker by coal feeding system and be fed into gasifier Gas produced by gasifier is removed dusts by gravitational dust cleaner and cyclone dust catcher and finally be sent to user.

COLD GAS STATION OF SINGLE STAGE GASIFIER(ANTHRACITE)

The technological flow(anthracite):unpurified gas produced by gasifier, which temperature is 400 - 600°C, gets into double-standpipe to be cooled by hot circulating water and washed out part of dust which discharged from the bottom water seal Then the gas gets out from the top of standpipe which temperature is 80 - 90°C, and then gets into the washing tower for cooling and dust removing, the temperature is lowered to 35 - 45°C. After removed dust by electrostatic precipitator, the gas is pressurized by gas booster fan, desulfurized by desulfurizeding tower, and removed water by drop catcher, at last be sent to the user.

INTRODUCTION OF TWO-STAGE GASIFIER TECHNOLOGY

The two- stage coal gasifier is a gasifying equipment including carbonizing stage and gasifying stage, with 40- 60mm bituminous coal for fuel. In the upper stage coal is carbonized. The carbonized coal becomes semi cokes, then gets down to be gasified in lower stage Carbonization and gasification of coal are finished in the same equipment. The carbonizing and gasifying gas, after optimized allocation is disposed by dust- removing, tar-removing, Cooling and sulfur- removing technology. The clean coal gas out of gasifier is supplied to industrial kiln by gas pressure adding and transmission system .According to different requirements on coal gas quality of various kinds of kiln , it is composed of two-stage hot detarring gas and two-stage cold clean gas, two different technologies. The whole system includes coal lifting system, coal lifting system, air supplying system, two-stage gasifier gasifying system, dust-removing and purifying system, light oil catching and recycling system, phenol water disposal and incinerating system, desulphurizing system, auto-control system, gas storage, pressure adding and transmission system.

HOT DETARRING GAS STATION OF TWO STAGE GASIFIER

The technological flow: Up-stage gas gets into electrostatic precipitator, which work temperature is between 90 - 150°C, where the tar fog-drops and dusts are polarized and then in fluxed on inside wall of polar tube, and finally flows automatically to tar pool. Firstly, downstage gas gets into the cyclone dust remover and centrifugally separated. The temperature is lowered to abou450 - 550°C. Up-stage gas is mixed with down-stage gas and then sent to users.

COLD GAS STATION OF TWO STAGE GASIFIER

Decontaminating and cooling process of up-stage gas: Up-stage gas firstly gets into electrostatic precipitator, which work temperature is about 90 - 150°C. In this part,heavy tar and dust are separated. Up-stage gas then gels into indirect cooler, in where the gas is cooled to 35 - 45°C. Firstly, dust is centrifugally separated from down-stage gas and the temperature is lowered to about 450 - 550°C, secondly, the gas comes into exhausted heat exchanger to recover the gas sensible heat with the temperature dropping to about 180- 220°C; thirdly, the gas temperature is dropped to 65 - 80°C in wind cooler; and finally, its temperature is lowered to 35 - 45°C by circulating cooling water in indirect cooler. Then the up-stage gas mixed with down-stage gas gets into electrostatic precipitator II to remove oil and dust again. The gas is pressurized by gas booster fan, desulfurized by desulfurizing tower, and then sent to the user.