Study On Technology-Economy-Environment Assessment Of Methanol-based Olefins

Evaluation method and model (CCTM) have been accomplished by Clean Coal Engineering & Research Center of Coal Industry (CCT), but methanol to olefins technology is not involved. Based on the work completed by CCT, adopting MTO kinetic model and demonstration result proclaimed by Lurgi, according to feasibility study report of coal-based olefins technology model, economy model and environment model are obtained. Simultaneously, the model is linked to the CCTM, by which coal-based olefins, coal-based oil and coal-based methanol and so on can be evaluated and compared with.In DMTO technology evaluation model, with the kinetic model, the mass of C₁, ethylene, propylene, C₄ and C₅⁺ are 0.0084 ton, 0.103 ton, 0.205 ton, 0.022 ton, 0.072 ton and 0.027 ton for one ton methanol in the balance system, respectively.In MTP technology evaluation model, according to demonstration result proclaimed by Lurgi, methanol consumotion, gasoil, LPG and craftwork H₂O are 3.22 ton, 0.258 ton, 0.1 ton and 1.765 ton per propylene, respectively.After interrelated economy parameters are input, evaluation results of DMTO technology and MTP technology are obtained by the model built. Technology evaluation result of DMTO technology is as follows: the mass of polyethylene, polypropylene, C₄ and C5+ per year are 235,800 ton, 364,200 ton, 76,200 ton and 48,000 ton, respectively and system enegy efficiency, consumption of water, electricity and steam per ton product are 76.37%, 12.8 ton, 543kWh, 5.82 ton, respectively. Economy evaluation result of DMTO technology is as follows: investment, production cost per ton produt are 5438.34 yuan and 5301.08 yuan, respectively and IRR is 25.67%. Environment evaluation result of DMTO technology is as follows: waste water and solid waste per ton product are 1.5 ton and 1.12kg, respectively. Technology evaluation result of MTP technology is as follows: the weight of polypropylene, petrol, LPG per year are 600,000 ton, 14,000 ton, 92,000 ton, respectively and system enegy efficiency, consumption of water, electricity and steam per ton product are 66.36%, 18.2 ton, 485.7kWh, 5.2 ton, respectively. Economy evaluation result of MTP technology is as follows: investment, production cost per ton produt are 4483.92 yuan and 5438.92 yuan, respectively and IRR is 27.61%. Environment evaluation result of MTP technology is as follows: waste water and solid waste per ton product are 1.76 ton and 0.56kg, respectively. It is indicated from the model result tested that evaluation model built is correct.It is indicated from the index comparision between DMTO technology and MTP technology that DMTO consumption (except electricity and steam) is lower, system energy efficiency is higher, investment and production cost per ton product are higher, discharge of waste water is lower and discharge of solid waste is higher.