A Design On C5/C6 Paraffin Isomerization Process

Based on some company's catalytic reforming complex units,this paper has designed the process of light paraffin isomerization unit,whose capacity is 200,000 tons / year.The product of the unit is isomate,which is used to mix in the gasoline to improve the octane number.It can contribute to the upgrade of gasoline.According to product requirements,properties of raw materials and characteristics of all technologies,I have made a choice of the technology,finally determined the low-temperature isomerization as the technology.Then three different processes were chosen,which based on product requirements and the relevant reference.The three different processes are simulated and calculated by the chemical simulation software.With the comparison of the properties of the final program,energy cons umption and economic indicators,it showed that the product RON of program 1 didn't achieve 88,and the energy consumption of program 3 was 1312.85MJ·t-1,which is larger than that of program 2,the investment of program 3 was 1.1 times that of program 2.the program 2(one through + DIH)not only met product requirements very well,but also had low unit investment and energy consumption,so ultimately this unit was determined to use the program 2 as the design process.This paper used Aspen Plus and HTRI as the simulation and calculation software.The unit operating flexibility is 60 to 110%,process is one through + DIH,product octane number is 88.54,vapor pressure is 106.6Kpa,and energy consumption is 1193.5MJ · t-1.During designing,this paper especially did the simulation and analysis of main device – stabilizer and deisohexanizer,the stabilizer is valve tower,the size is ?1100/1700mm×24500mm,the deisohexanizer also use float valves,the size is ?3000mm×55300mm,at the same time,this paper completed other ancillary equipment calculation and selection,such as heat exchangers and pumps.The unit energy consumption is mainly steam and electricity consumption,so this paper made a number of energy saving measures to save steam,including the use of waste heat of process material,the use of air cooling,etc.For example,The use of toluene column bottoms instead of the low-pressure steam heat to provide the necessary heat of deisohexanizer bottom reboiler,which saves 2055.4MJ / t energy and 15.38 t / h steam.This paper can provide a reference for process design and equipment selection of other C5/C6 paraffin isomerization units...