A Continuous Absorption Process Design For Sulphuric Acid In Battery

Lead acid battery is the most widely used secondary battery because of its excellent performance and low price.It is commonly used in industry,transportation,communications,power and other systems.With the oil crisis and the urgent need to reduce environmental pollution,green energies,such as wind power and solar power have gradually emerged,and various types of vehicles powered by electric energy have been widely used.The acid demand for batteries is increasing year by year.But the conventional production process of this sulfuric acid is less continuous,and its capacity is small and unsafe.In this design,sulfur trioxide gas in the sulfur acid production industry is used as a raw material and the continuous absorption process is adopted.The production capacity reaches 50,000 tons per year.In this design,the author made material balance,heat balance,key equipment calculation,etc…And based on the calculation results,the material balance table was drawn for the absorption process.In this paper,HAZOPO,an advanced method,is used to perform dynamic security analysis of the system.In this design,the author selected PTFE material in the absorption section,which can reduce the metal impurities in sulfuric acid from 0.001%to less than 0.00002%.In the design process,the author designed a heat exchanger between the outlet gas and the inlet gas of the absorption column.So that the heat recovery could be sufficient and the inlet gas temperature could be reduced from about 150?to below 100?.To control sulfur dioxide content in the sulfuric acid,the oxidation of sulfur dioxide with hydrogen peroxide technique was adopted.By adjusting the addition manner of hydrogen peroxide,the sulfur dioxide content in sulfuric acid could be reduced from 0.02%to less than 0.0003%.In this design,the SO₃ consumption for the production of 50,000 tons of sulfuric acid for lead-acid batteries is 40,800tons,the required power is 640,000 kW?h.The output value of this design is?22.5 million,and the profit is?13.54 million.As compared with the traditional technology,this design has several advantages.Firstly,the traditional production process of sulfuric acid for batteries is changed.In the traditional production process,sulfuric acid is firstly produced and then manufactured to the acid for batteries.Secondly,the whole production process is under automatic controlling,greatly improving the working efficiency.Thirdly,the exhaust gas could be returned to the converter in the industrial sulfuric acid production process,taking part in the reaction.The production process is environmentally friendly without the increase in exhaust gas emission.