The Process Simulation Analysis And Energy-Saving Revamp Research Of The Lubricant Hydrotreating Unit

With the increasing proportion of the sour crude oil and heavy crude oil inrefinery, hydrogenation technology has become more and more important. However,the comprehensive energy consumption of hydrogenation process in domestic are stillinconsistent. So, optimizing the process, maximizing the energy-saved and reducingthe use amount of the public matter are important.With the process data of lube oilhydrotreating unit,strict simulation was completed and research of current heatexchanger network was also completed using pinch technology based above simulationresults.Details of the researches are summarized as below.Based on the lube oil hydrotreating unit processes data, the strict mathematicalmodel was established.Firstly, According to distillation data of the raw material oil,theraw oil was cut into " virtual components " and the PENG-ROB state equation waschoosed as physical property calculation methods according to the material systeminvolved in the process. Then calculation was completed after selecting the appropriateunit module, determining the numbers of break streams needed, selecting theWEGSTEIN convergence method. Results shows that comparing the simulated valueand the calibration value, the relative error is less than4%, the model can reflect theactual operation device. The simulation results and calibration data are so fit that asolid foundation is lain for the need of optimizing the heat exchanger network.Through the situation of the energy consumption from the calibration data in2010,the energy consumption situation of the unit is analyzed.The main reasons whycalibration energy consumption is higher than the designed energy consumption arefound: Fuel gas and1.0MPa energy consumption proportion are higher than the designenergy consumption proportion.The heat exchanger network was studied using pinch analysis techniques withabove process simulation results. First, set the minimum temperature differencebetween the hot and cold streams at20℃, using the extracted stream data, the hot andcold composite curves were made, and it could found the minimum cold utility was1528kW, the minimum hot utility was1342kW, which determined the energy target. According to the heat exchanger network technology, using of pinch point theory,current heat exchanger network was analyzed and five places crossing heat transferpinch were found,discovering using a cold utilities above pinch point and using hotpublic works under pinch point. According to the principles of pinch theory, heatexchanger network reconstruction scheme1was obtained.The results shows that1132kW was saved, with the amount of cold utilities saving38.8%and the amount of hotutility savings41.4%. Saving energy is81.4%of the total potential energy saved of theoriginal heat exchanger network.Based on the maximum heat recovery heat exchanger network, scheme2of heatexchanger network was obtained The results shows that1342kW was saved, with theamount of cold utilities saving47.7%and the amount of hot utility savings50.9%.