煤热解焦油化学破乳脱盐试验研究

为减少煤焦油乳状液水中大量无机盐对分馏塔冷凝器等设备的腐蚀,促进煤焦油与水分离,利用化学破乳方法对煤焦油进行了脱盐试验,探讨了煤焦油化学破乳的可行性,考察了破乳剂类型、破乳剂添加量、注水量、脱盐温度及停留时间等试验条件对煤焦油脱盐效果的影响。结果表明,自制聚醚破乳剂脱盐效果较佳,破乳剂添加量100×10~(-6),注水量15%,脱盐温度110℃,脱后煤焦油中盐含量均出现明显拐点,停留时间在一定范围内对脱盐效果影响甚微。因此,自制聚醚破乳剂较其他2种较广泛应用于煤焦油脱水的破乳剂具有更好的脱盐效果,这主要归因于其特殊结构与煤焦油中沥青质有很强的相互作用。

Study on chemical demulsification and desalination of coal pyrolysis tar

In order to reduce the corrosion of inorganic salts from emulsion water in the coal tar to the fractional distillation condenser and accelerate the separation of coal tar from water,the desalination test of coal pyrolysis tar was carried out by chemical demulsification.The feasibility of chemical demulsification of coal pyrolysis tar was discussed.The effects of test conditions such as demulsifier type,demulsifier addition,water addition,desalination temperature and residence time on the desalination of coal tar were investigated.The results show that the self-made polyether demulsifier has better desalination effect.The addition of demulsifier and water are with amount 100 × 10-6 and 15 ％ respectively,and the desalination temperature is 110 ℃,the salts content in the oil are obvious decreased.The residence time has little effect on the result within a certain range.Therefore,the self-made polyether demulsifier,which is mainly attributed to the strong interaction with special structure of asphalt in coal tar,demonstrates better desalting effect comparing with the other two kinds of widely used demulsifier.