本发明提供一种甲醇脱水制二甲醚的方法,包括以下步骤:甲醇先经两级换热再经加热达到120~160℃,然后在催化剂作用下,脱水生成二甲醚、甲醇和水的混合物;生成的二甲醚混合物直接分离提纯,得到合格的二甲醚产品和含醇工艺水;得到的含醇工艺水直接分离提纯,得到合格的甲醇和合格的废水;得到的合格的甲醇加热至120~160℃,再次进行 The invention provides a method for dehydrating methanol to dimethyl ether, which comprises the following steps: firstly, the methanol is heated by two stages of heat exchange and then heated up to 120-160 DEG C; and then the catalyst is dehydrated to produce dimethyl ether, methanol and water Mixture; the resulting dimethyl ether mixture is directly separated and purified to obtain qualified dimethyl ether product and alcohol-containing process water; the obtained alcohol-containing process water is directly separated and purified to obtain qualified methanol and qualified wastewater; the obtained qualified methanol is heated To 120 ~ 160 ℃, again