Joint production process of alcohol and ammonia

The process of co-producing alcohol and ammonia with the discharged gas from methanol producing apparatus as the material gas includes the following steps: 1. producing hydrogen with purity higher than 98 % in a pressure swing absorption set with the discharged gas, and adding nitrogen from low temperature air separating plant or nitrogen producing pressure swing absorption plant to obtain mixed gas in the H2/N2 ratio of 3.00-3.10; 2. methanation reaction of H2 and CO in the mixed gas to obtain fresh methane gas; and 3. cooling and pressurizing the fresh methane gas and synthesizing ammonia in an ammonia synthesizing loop, and cooling and separating to obtain liquid ammonia. The process is short, low in cost, and low in power consumption.