Industrial application of polymeric environmental desulfurization agent(1)

Wet desulfurization is a desulfurization technology that uses liquid absorbers such as alkaline solutions to wash the tail gas to remove SO2 from the tail gas, and the desulfurization efficiency can reach about 95%, and many cement plants in China have adopted wet desulfurization technology. 

The problems of this technology are: large land area, high investment; easy wear and tear of equipment, corrosion and secondary waste generation. This type of desulfurization is suitable for cement enterprises with very high long-term sulfur emissions.

Ammonia desulfurization, from the national sampling results can be known that most domestic cement kilns SO2 emission concentration range between 0 ~ 500 mg/Nm3, usually do not need to choose the wet desulfurization process, ammonia desulfurization process is more appropriate. 

The ammonia desulfurization method is to spray ammonia into the preheater after atomizing it with a high-pressure gun at the position of the preheater secondary cylinder, so that it reacts with the SO2 in the preheater to produce products such as sulfuric acid and ammonia, and some of its products are excluded with the flue gas and some flow to the rotary kiln with the material. 

The advantage of this method is the low cost of equipment investment, easy to use and flexible, according to the high and low sulfur content to adjust the amount of doping, can effectively solve the sulfur emissions in cement enterprises within 500 mg/Nm3 sulfur emissions exceed the standard problem, the disadvantage is that the ammonia water alkaline heavy, corrosion of equipment, and easy to cause ammonia escape to form secondary pollution.

Desulfurization mechanism of desulfurization agent

Through the analysis of SO2 generation and current desulfurization technology, it is proposed that the technical solution of the project should meet the requirements of flexible and easy use, high desulfurization efficiency, low investment cost, and no harm to people and equipment for ecological protection. 

Based on the formation mechanism and emission process of SO2 in cement kilns, desulfurization is achieved by catalytic activation and efficient adsorption, in which catalytic reaction can reduce the activation energy of the reaction, while adsorption provides both the basis for the adsorption and oxidation reaction of SO2 and the solid-phase medium for the reaction of catalytic activation, so the synthesis of unique polymeric substances makes it possible to have abundant groups on the main chain, which in turn can provide More adsorption sites are available.

In summary, the desulfurization agent should consist of three parts: oxidant, surfactant and polymer activation adsorbent.