The Comprehensive Utilization And Development Of Styrene Tar

Styrene tar is a by-product in the production of styrene. At present, Styrene tar products are mainly used as fuel oil, it is low utilization rate and low economic efficiency. According to the relevant literature, styrene tar is used as boiler or cracking furnace fuel, it is not easy combustion,and combustion is easy to produce black smoke or coking, causing environmental pollution. So the rational use of styrene tar to produce a high economic benefit, it has a significant impact on the overall efficiency of the styrene unit and the processing of the by-products of styrene, which is the important task of styrene at home and abroad after processing industry to be solved.In this paper, we mainly study the comprehensive utilization and technology development of styrene tar. Through ordinary distillation and distillation to obtain light gasoline components,Styrene, trans-Stilbene and heavy diesel components, In order to achieve the purpose of recycling of waste.In this paper, the former treatment of tar, namely the ordinary distillation stage, the concentration of Na OH solution, solvent and oil mass ratio, operating temperature of three factors were experimentally tested.By observing the color difference and volume ratio of the extract,gas volume expansion curves of various fractions,the optimum process conditions are found out.Experimental results show: The concentration of Na OH solution is 8%,the concentration of Na OH solution and the volume ratio of styrene tar are1.2:1,mixing time is 25 minutes, pretreatment of styrene tar to be achieve the best recovery effect.According to the determination of the content of styrene in light gasoline reached 27%, At the same time,trans-Stilbene was purified by recrystallization.The post treatment of styrene tar is the rectification part, the main problem is that the recovery and extraction of styrene in the light gasoline component is carried out.This part of the main research variables : vacuum distillation tower, reflux ratio.Through a lot of distillation experiments show that, vacuum degree is0.08 MPa, reflux ratio is 4, the purity of the obtained styrene can reach 98%.According to the relevant technological parameters obtained from the experiment, the process design for the recovery of styrene tar is as follows: firstly, the tar raw materials in the tank were pretreated by alkali and preheating, then the alkali washed tar was three times of evaporation, condensation, filtration and other unit operations, four different co boiling mixtureswere obtained. Finally, the separation of waste water produced in the process of recovery and utilization of waste heat. The separation process was optimized by the chemical process simulation software, and the process of material balance and heat balance calculation, type selection and size calculation for main equipment,the process flow diagram using Auto CAD drawing each section.