Is desulfurizer a hazardous material?

Desulfurizing agent is not a dangerous product. The common desulfurizing agent is calcium hydroxide, which is a strong alkali and has certain corrosive effect on the skin.

When the skin is covered with calcium hydroxide solution, it needs to be wiped with a rag and then coated with a certain concentration of boric acid solution.

Desulfurization agent generally refers to the agent that removes free sulfur or sulfur compounds from fuels, raw materials or other materials; in the control and treatment of pollutants, it mainly refers to the agent that can remove sulfur oxides (including SO2 and SO3) used in exhaust gases. Various alkaline compounds can be used as desulfurization agents.

The most used desulfurization agent to remove sulfur dioxide in flue gas is inexpensive lime, limestone and alkaline solutions prepared with limey agents. Desulfurizing agent can absorb most of the sulfur dioxide in the flue gas fixed in the fuel slag. Chemical plants, smelters, etc. often use sodium carbonate, alkaline aluminum sulfate and other solutions as desulfurization agents to deal with tail gas containing sulfur dioxide, and can be desorbed and recycled.

This mixed solution desulfurization agent has surface activity and catalytic oxidation, which can sexually promote the direct reaction of SO2, accelerate the dissolution of CaCO3, promote the rapid oxidation of CaSO3 to CaSO4, strengthen the precipitation of CaSO4, reduce the liquid to gas ratio, reduce the calcium to sulfur ratio, and reduce the evaporation of water.

Broaden the selection range of desulfurization materials and improve the reliability of the system. Under different working conditions, slurry circulation pump and oxidation fan can be reduced and deactivated to improve desulfurization efficiency, reduce operating costs, suit the variation of sulfur content in coal, and apply to high sulfur coal. In the application of flue gas desulfurization, it has the advantage of broad market promotion and can produce considerable economic and social benefits.

The reaction of H2S with MDEA (N-methyldiethanolamine) in liquid desulfurizer due to proton transfer is several flat as a transient chemical reaction controlled by a gas film.

H2S+R2NCH3=[R2NHCH3]+[HS]-

Since MDEA is a tertiary amine, CO2 undergoes an acid-base neutralization reaction with the amine only after the formation of bicarbonate with water.

CO2+H2O+R2NCH3 R2NHCH3+HCO3

Because CO2 and water require a slow intermediate process, this large difference in reaction rate forms the basis for selective absorption, i.e. MDEA has a high selectivity for H2S absorption in the presence of CO2.

The acid exhaust gas is washed with water to remove CH3OH and HCN and then enters the bottom of the absorber tower in counter-current contact with the lean amine solution added from the top, and the desulfurized purge gas escapes from the top of the tower. The rich amine solution leaving the absorption tower is heated by heat exchange with the lean amine through a heat exchanger and then regenerated in the regeneration tower, and the regenerated acid gas containing H2S and CO2 removed is used as feed to the Kraus unit, and the lean amine is sent to the absorption tower by a cooling pump.