Research On The Plan Of Regulating The Dilution Ratio Of Daqing Naphtha Pyrolysis

At present, with the change of oil pyrolysis producing ethylene on our country, the urgent optimization of rules and processes of naphtha pyrolysis producing ethylene and with the development of computer technology, the technology which simulates pyrolysis process also gains a great improvement for understanding the rule and optimization method of various oil pyrolysis.The method regulating dilution ratio in present industrial production can make residence time change. So ethylene yields obtained with this method are affected not only by dilution ratio but also by residence time. Through massive analysis and computation, this article revised pyrolysis experiment method and proposed improved experiment technique of controlling dilution ratio independently. The method that controlling the total of inlet hydrocarbon and water flow rate can compute individual hydrocarbon and water flow rate in different dilution ratio and can eliminate the change caused by regulating dilution ratio, so the true influence of dilution ratio on ethylene yields can be known. This article has simulated and calculated the process of Daqing naphtha pyrolysis with self-designed two-dimensional technological mathematical model and inspected the influence of three operating conditions on ethylene yield in different temperature, residence time, the dilution ratio, as well as the impact of the interaction among three factors on ethylene yield from range analysis and variance analysis of orthogonal design. With this method the interaction between residence time and dilution ratio decreases. The feasibility of this new method is proved.Using self designed and built pyrolysis experiment device and improved dilution ratio determining method, pyrolysis experiments on Daqing naphtha were done and the rule of naphtha pyrolysis producing ethylene was studied. The rule obtained from pyrolysis experiment device was consistent with the rule of naphtha pyrolysis, so pyrolysis experiment can be done with small device instead of big device. While doing experiment using new method to regulate dilution ratio, the change rule of ethylene yields with residence time and dilution ratio under different temperature is perfectly consistent with the reported literature. The feasibility doing experiment with new method regulating dilution ratio is verified.