| In order to optimize the product structure, improve the economic benefit, the Petro-Refinery in Dalian Development Zone put the Alkylation unit into use which shutdown for years. According to the environmental protection in our country, building a set of waste sulfuric acid regeneration device is a way to make the waste sulfuric acid re-produced and recycled. Through comparative research of the waste acid regeneration process, for China National Offshore Oil Corp huizhou refinery, Petrochemia-Blachownia S.A. in Poland, Slovakia Slovnaft refinery field,with further studies on the performance of the waste acid device, the company decided to build a set with WSA device.Waste sulphuric acid regeneration device uses the extension of WSA process. The waste sulfuric acid is pyrolyzed into sulfur dioxide at high temperature, together with air being iintroduced through the conversion of sulfur dioxide into sulfur trioxide. Then the gas enters a falling film condenser and the process gas entraines water vapor which will becondensed to form new acid. The concentration can reach more than 98%. During the sulfuric acid regeneration unit newly started running, the waste heat boiler tube blockage, acid gas emissions of non-compliance and other issues emerge. Continuous exploration have been tried, such as the installation of purge steam taken to replace the new burner, optimizing feed composition to eliminate clogging tubes,improving demister effect, to enhance the cooling air flow, adjusting the amount of silicone oil steam and other measures to eliminate the phenomenon of acid gas emissions from non-compliance. And a host of other problems found in the production process, are also conducted a detailed study, The development of relevant actions and programs are made, so that these problems are basically solved in time, providing a reliable guarantee for the stable operation of the spent acid regeneration unit.SO2 converter is the main reaction apparatus in acid regeneration unit, which is a three-stage adiabatic reactor. The heat exchanger between the three sections bed put the heatof reaction away. Process gas passed through a catalytic bed of VK type catalyst to produce SO3 gas and some steam. In the SO2 converter, the period of bed play a major role. According to design data provided, most reactions occur in thefirst bed and the temperature rise is the largest section in the bed, so the research on the reactor for SO2 conversion and optimization at the first bed becomes particularly important.In order to let the study in depth, we collaborative system simulation evaluation method, the introduction of the S system simulation. In S system simulation, a set of nonlinear differential equations are rewritten into a standard form S system, and the variable order and step size of the Taylor seriesis used to solve them. The method used in the chemical system is not very extensive, but it has high accuracy, good error predictability, wide applicability and high operational efficiency. Through the data of SO2 conversion analog,we calculated the SO2 conversion rate and bed temperature in the converter with bed depth changing. The effect of temperature on the conversion of SO2 conversion rate is also studied.The results show that the S model designed for the conversion of SO2 simulation works well at different conditions. It calculated the SO2 conversion rate and reaction temperature, with bed depth deepening gradually,both of them increased. The results and design data are more consistent on the trend, This article describes the system model built for S acidic wet gas sulfuric acid process,anddesign and the optimization of SO2 converter is reliable. The simulation results can serves as valuable informations for process design. |
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