乙烯法与合成气法生产乙二醇的成本比较

Cost Analysis of Mono-Ethylene Glycol Produced Using Ethylene or Synthetic Gas as Feedstock

比较了乙烯法和合成气法两种生产乙二醇工艺的反应本质,从原料、副产品、公用工程、投资等方面全方位计算了两种工艺的生产成本。乙烯法虽然消耗高价格的乙烯原料,但与低成本的水反应生成乙二醇,乙烯价格仅占原料成本的60%;而合成气法公用工程消耗量大,费用成本占25%左右,是乙烯法的2.4倍。将两种工艺计算得到的乙二醇生产成本分别与原油、煤和天然气的价格挂钩,结果表明低油价下乙烯法生产乙二醇的成本在4 600元/t以下,具有较明显的成本优势;以煤为原料的合成气法成本在5 000元/t以下,在高油价下才有竞争力;而以天然气为原料的合成气法竞争力最弱。

The reaction characters of mono-ethylene glycol （MEG） production, separately using ethylene or synthetic gas as feedstock, were substantially compared. The operating cost of MEG was then calculated covering the feedstock cost, by-products value, utilities expense and capital investment. Though ethylene price is relatively high, the cost of MEG is not strongly sensitive to the price of ethylene owing to the reaction with water with low price, only 60% of the cost of materials. In contrast, the expense on utilities using synthetic gas to obtain MEG contributes 25% to the total cost of MEG because of the large consumption. The results were then shown in a diagram by relating the calculated cost with the price of Brent oil, coal and natural gas. The conclusion was drawn that the operating cost of MEG using ethylene as feedstock was less than 4 600 RMB/t, taking the advantage of low oil price. The production of MEG based on coal, cost of which was approximately 5 000 RMB/t, was more competitive in the condition of high oil price. Natural gas could hardly compete with crude and coal in producing MEG because of its high price.