Review

The earliest method of wet desulfurization application is ammonia washing neutralization method. Since the emergence of ADA method abroad in the early 1950s, China has also developed improved ADA method, MSQ method, KCS method, tannin extract method, 888 method and other desulfurization technologies.

Compared with dry desulfurization, the application of wet desulfurization technology is relatively late. Wet desulfurization technology has long been applied in the purification of coke oven gas and water gas. With the development of industry and the increasing demand for purification of generator gas in environmental protection, wet flue gas desulfurization technology has only begun to be applied in the generator gas industry. The application of wet desulfurization technology in the purification of furnace gas is slightly different from its application in the purification of coke oven gas and water gas, with slight adjustments to desulfurization equipment, processes, and operating parameters.

1 Wet desulfurization process flow

1.1 Gas Process

The purified gas transported by the gas compressor enters the desulfurization tower from the lower part, passes through the packing layer, and comes into reverse contact with the desulfurization lean solution sprayed from the top of the tower to completely remove hydrogen sulfide. The purified gas is discharged from the top of the desulfurization tower and enters the droplet catcher to remove large particles of mist droplets before being sent to the gas consumption point for use.

1.2 Process of alkaline desulfurization solution

The desulfurization pump extracts the lean solution from the lean solution tank, pumps it to the top of the desulfurization tower, and sprays it down from the top of the desulfurization tower. In the desulfurization tower, the gas and desulfurization solution come into countercurrent contact, and the gas-liquid two-phase contact occurs on the surface of the packing, completing the process of absorbing hydrogen sulfide. After the solution absorbs hydrogen sulfide, it accumulates at the bottom of the desulfurization tower and flows into the rich liquid tank.

The solution entering the rich liquid tank is sent to the jet regeneration tank by the regeneration pump. The liquid jet (self-priming air through the injector) interacts with the sucked air in the injector and regeneration tank to complete the oxidation regeneration and sulfur precipitation process of the desulfurization rich liquid. The regenerated desulfurization lean liquid flows into the lean liquid tank through the liquid level regulator and is then pumped into the desulfurization tower by the desulfurization pump for continuous desulfurization.

At the same time, the sulfur foam in the upper floating sulfur layer in the spray regeneration tank overflows to the sulfur foam collection tank, and then is discharged into the filter press through the foam pump after being collected.