شبيه سازي با سيستم الكتروليتي جهت كنترل PH و جايگزيني عملي ماده تجارتي ضد خوردگي با محلول آميني در واحد بنزين پيروليز (تفكافت)

Replacing Commercial Anticorrosion by Amine Solution in Pyrolysis Gasoline Hydrogenation Plant in Arak Petrochemical Company ; pH Control Simulation Based on Electrolyte System

There was a high rate of corrosion in pyrolysis gasoline hydrogenation unit of Arak petrochemical company (PGH), and it was caused some operational problem in this plant. A trademark chemical anticorrosion which is called C39 , was used to inject in the depenthaniser overhead in order to control the corrosion rate. Injection of commercial corrosion inhibitor causes some operational problems, for example fouling in some heat exchangers. Therefore R&D specialists proposed to replace C39 by effective and well-known additive. At first, the system was simulated by CHEMCAD software in electrolyte system to specify low pH points of the plant. Then , ammonia\monoethanol amine solution was proposed as neutraliser to inject in the plant. After it ,depentaniser and its accessories was simulated in case of injection of this solution. According to the simulation results , injection of new anticorrosion has no side effect on C5 cut product and operating condition of the column. The corrosion rate will be cotrolled if pH remains at the range of 6.5 to 8. Test run also carried out in the plant by injection of ammonia\monoethanol amine solution at the rate of 0.6 Kg/hr and iron content of the water samples and corrosion test coupon confirmed the simulation results. Now, ammonia\monoethanol amine solution is injected to the plant and corrosion rate has decreased resonably.