The coal gas desulphurization method as a whole is divided into two kinds: hot gas desulfurization and cold gas desulfurization. In our country, hot gas desulfurization is still in the experimental stage, has yet to be further improved, and the cold gas desulfurization is a relatively mature technology, the desulfurization method is very much.

Cold gas desulfurization can be divided into two kinds of dry desulfurization and wet desulfurization method, desulfurization with oxide and activated carbon method is widely used, and wet desulfurization by the arsenic alkaline process, improved ADA and extract method representative.

A, the disadvantages of dry desulfurization

(1) dry oxide desulfurization

Heavy equipment, mostly for the intermittent regenerative desulfurization adsorbent regeneration, each regeneration is completed, must use the residual air in steam blowing gas analysis, after passing, can pour tower aspirated, otherwise it will cause an explosion; in addition, the replacement of desulfurizer, the labor intensity of the operation, operation is not as easy to fire burning, more dangerous.

(2) dry desulfurization activity

Superheated steam desulfurizer regeneration is not easy to obtain, and the regeneration effect is difficult to meet the requirements, the majority of manufacturers simply do not replace the activated carbon regeneration, but after removal of the new.

Dry desulfurization, due to sulfur adsorption, increase desulfurizing agent bed layer resistance, which is caused by the fluctuation of gas pressure, is not conducive to the normal gas burning kiln before; in addition, the dry desulfurization, the desulfurization efficiency decreases with increasing application time of desulfurization agent, is not conducive to the control of the final product quality; moreover, due to the dry desulfurization belong to intermittent regeneration, in order not to affect the enterprise continuous production, must set the alternate desulfurization tower, resulting in waste of idle equipment.

Two, the advantages and disadvantages of wet desulfurization by tannin extract

1, the advantages of wet desulfurization by tannin extract

Wet desulfurization by tannin extract desulfurization and regeneration process for the continuous on-line process, desulfurization and regeneration at the same time, do not need to set aside the desulfurization tower; gas desulphurization purification degree can according to the needs of enterprises, the adjustment solution ratio, timely control, stable gas after purification H2S content.

2, wet desulfurization by tannin extract defect

Many devices, the process operation is complex, the equipment investment is large.

3, operation cost

The desulfurization system operation cost from the gas station, desulfurization by activated carbon and iron oxide desulfurization is wet desulfurization slightly lower, but considering the need to dry desulfurization regeneration cost, then dry desulphurization and wet desulfurization method, the operation cost difference.

Three, combined with the application of dry desulfurization and wet desulfurization technology

For some of the H2S in gas sensitive industries, can be combined with the advantages of dry desulfurization and wet FGD technology, two kinds of desulfurization methods combined, using the gas wet desulfurization in most H2S removal, then, using dry desulfurization of coal gas in H2S so as to achieve fine removal, desulfurization, cleanliness high. This not only makes use of the advantages of wet desulfurization can be adjusted online, and use of the advantages of the dry desulfurization of high desulfurization efficiency, and overcomes the dry desulfurization desulfurization desulfurizer agent caused by the problem of excessive failure.