What does HPF desulfurization process mean?

1 Introduction to HPF desulfurization process.

The HPF desulfurization process uses ammonia in coke oven gas as an absorbent and HPF as a catalyst for wet oxidative desulfurization, which first converts H2S in the gas into ammonium sulfide salt, which is converted into elemental sulfur under the oxidation of air, and the absorption solution is regenerated. The main ones are (1) absorption reactions.

2) Regeneration reaction (3) Fu reaction. HPF has a catalytic effect in the whole process of desulfurization and regeneration.

This process is basically the same as ADA desulfurization. The gas entering the desulfurization section enters the series of air-jet desulfurization tower and packing desulfurization tower in turn, and is in reverse contact with the desulfurization liquid, and the gas removes H2S and HCN to remove ammonia; The desulfurization tower has its own independent regeneration system, and the desulfurization solution that absorbs H2S and HCN is sent to the corresponding regeneration system respectively, and the solution is regenerated and recycled under the action of air; The sulfur foam flows into the foam tank, is clarified and layered by stirring, and is further melted to form sulfur products.

2 Process characteristics of HPF desulfurization.

1) The desulfurization device is placed in front of the ammonia absorption and crude benzene section in the whole gas purification process, the process is reasonable and simple, and the HCN removal rate in the gas reaches 75%, which can cancel the yellow blood salt process, which has certain benefits for improving the environmental pollution of final cooling water and reducing the corrosion of pipeline equipment.

2) The desulfurization and cyanide removal effect of the desulfurization process is good, the desulfurization efficiency can be greater than 99% under the production conditions, and the H2S content of the gas after desulfurization is less than 50 mg m3.

3) HPF has extremely high activity and catalyzes both desulfurization and regeneration processes. At the same time, it was also found that HPF had the effect of eliminating the wall sulfur in the desulfurization tower, and the resistance of the packed tower gradually decreased from the original 2 500 pA to 1 200 pA after the use of HPF.

4) Since this desulfurization process uses ammonia in coal gas as alkali source, there is no need to add additional alkali, the higher the ammonia content in the gas and the larger the ammonia-sulfur ratio, the higher the desulfurization efficiency, see Figure 2 for details.

5) Low operating cost, low power consumption and good economic benefits. See Table 4 for details.

6) The process is convenient and stable to operate, the catalyst dosing method is simple and easy, and the growth rate of by-products such as salts is slow in the desulfurization process.

The 3 HPF catalyst consists of hydroquinone PDS ferrous sulfate.

4 The control index of the HPF desulfurization solution is:

Hydroquinone. pds 8-10 mg/l

Ferrous sulphate. Free ammonia greater than 5g l

Ammonia thiosulfate less than 250g l

Suspension flow pH 8-9

HPF refers to a compound catalyst containing ferrous sulfate.

The HPF method is independently developed by China, which is a wet liquid phase catalytic oxidation desulfurization and cyanide decyanide process with ammonia as the base source and HPF as the composite catalyst, which has been successfully applied to many domestic coking enterprises.

HPF ammonia desulfurization process is a wet oxidative desulfurization method that makes the three components interact in solution and remove H2S under the action of catalyst according to the presence of NH3, H2S and HCN in coal gas at the same time. Oxidize H2S to elemental S.

The desulfurization process, HPF ammonia desulfurization, is actually an acid-base neutralization reaction.

The catalyst for HPF desulfurization is an aqueous solution composed of H (hydroquinone), PDS (bicyclophthalein cyanoammonium hexasulfonate), and F (ferrous sulfate).