Research On The Design Of PTA Hydrogenation Reactor Structure

PTA Hydrogenation reactor is the core equipment of producing PTA,which has complex structure and harsh operating conditions.Reasonable design of PTA hydrogenation reactor is the basis of obtaining high quality PTA product.Hence,studying the design method and the design process can provide references for the design of similar hydrogenation reactors.This paper introduces the design process of the PTA reactor.The main work and conclusitons are listed below:(1)The design process and design standards of PTA hydrogenation reactors were described.By comparing the characteristics of design standards at home and abroad,the ASME boiler and pressure vessel code,Vol.?,second chapters of United States was selected as the design standards in this paper.(2)The design parameters of the reactor were determined.The design pressure was 12.0MPa and the design temperature was 350 °C.Considering the medium characteristics,the high temperature and the high pressure,the materials of the PTA reactors were determined.Hydrogenation reaction medium characteristics and high temperature and high pressure hydrogen working environment based on analysis of the reactor materials,namely the base material with SA-387-11 CL.2,the parent body wall material shell welding stainless steel anti corrosion layer of TP.309 L + TP.347,forming a double metal structure.The base material was SA-387-11 CL.2.The stainless steel anti-corrosion layer will be built up on the internal wall of hydrogenation reactor shell,and the bimetallic structure will be formed,generally the austenitic stainless steel TP.309L+TP.347 of corrosion-resistant and good crack resistance will be used.(3)Based on the provisions of ASME,Vol.? second division,the thickness of the shell the thickness of the head shell were calculated.The values were 190 mm and 106 mm,respectively.Based on the engineering experience,the processing structure of flanging and wall butt welding the opening reinforcement for thick wall pipe forging was determined.By using finite element method ANSYS,the models of the opening parts were estimated.The stress analysis and evaluation of the dangerous section were performed.Results show that the nozzles can meet the strength requirements under design conditions.(4)The wind load and seismic load were calculated by PV-ELITE software as the loading condition accoring to standard provided by users.The finite element analysis and stress evaluation of the hot box position of the skirt were carried out by using the finiteelement software ANSYS.The results show that the hydrogenation reactor can meet the strength requirement.(5)An optimized throat type cold hydrogen pipe structure was proposed for the fatigue failure of the cold hydrogen pipe under high pressure and cyclic loading.The finite element analysis results show that the new structure can change the stress concentration zone of the original structure,avoid stress concentration due to temperature stress,and improve the fatigue resistance.(6)According to the situation of the serious flush and corrosion inside the reactor,a dissolver structure was raised to control the rate of spray,to improve the reactor efficiency and to reduce the equipment erosion.