提出了一种具有热集成的甲醇三效精馏工艺，并成功应用在50万t/a甲醇精馏提质增效改造项目中。采用专业的化工模拟软件对各主要精馏塔进行了模拟优化，新增高压精馏塔理论板数N=52层，回流比R≥2.5，进料位置N_F=48，加压精馏塔和常压精馏塔回流比分别为2.3和1.8，进料位置分别为48和45。改造后，精甲醇产量达到76万t/a，产品甲醇中乙醇质量分数降至0.01%以下，蒸汽单耗由原来的1.24 t/t降到了0.82 t/t，年增经济效益约3 944.6万元。

A novel triple-effect methanol distillation process with heat integration function is proposed and successfully applied to a certain 500,000 t/a methanol distillation project for quality and efficiency improvement.Professional chemical simulation software is used to simulate and optimize main distillation columns.The results are as follows:as for the newly-added high pressure distillation column,theoretical plate number is 52,reflux ratio is more than 2.5,and feeding location N_F=48;as for the pressurized and atmospheric distillation columns,reflux ratios are 2.3 and 1.8,respectively,and feeding locations N_F are 48 and 45,respectively.After technical renovation,the production of refined methanol reaches 760,000 t/a,the ethanol mass content in the product is below 0.01%,unit steam consumption per ton of methanol decreases from 1.24 tons to 0.82 tons,and economic benefit rises by RMB 39.446 million annually.