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A summary of the use of C307 methanol catalyst is provided by Deling Qi Zhaokun and Yang Fengying (Shandong Yankuang Cathay Chemical Co., Ltd., Tengzhou 277527) Yankuang Cathay Chemical Co., Ltd. uses low-temperature and low-pressure gas-solid-phase catalytic technology for methanol production, using C307 copper-based catalyst. The temperature reduction of the catalyst will affect the future activity and production capacity, so the filling and temperature reduction of the catalyst are summarized as follows. 1 Main equipment and processes The company adopts twin-tower parallel production. The synthesis tower is Φ3400mm×13289mm. The catalyst is filled in two layers. The upper layer is an insulating layer and the lower catalyst layer is a tubular type. Each tower is filled with 26.75m3 of catalyst, a total of 53.0m3. The bottom layer is filled with Φ8mm and Φ16mm refractory balls respectively. The main temperature points of the synthesis tower are the insulation layer temperature T1, the catalyst layer temperature T2 and the catalyst layer temperature T3. These three highest temperatures are used as the hot spot temperature as the basis for heating and reduction. The heating rate of the hot spot temperature of the synthesis tower is adjusted by the pressure of the steam drum, the 3.8MPa steam dosage and the H2 concentration. 2 Catalyst heating and reduction 2.1 Selection of process conditions (1) Pressure. Increasing the pressure can increase the airspeed and bring out more heat; a high partial pressure of hydrogen can speed up the reduction speed. However, if the pressure is too high, the linear velocity of the air flow will be small, which will easily cause flow deviation, and thus local over-temperature will easily occur. Therefore, the reduction pressure of this system is controlled at 0.7~1.0MPa. (2)Temperature. C307 copper-based catalyst should strictly control the hot spot temperature and should not exceed 230℃. During the reduction process, the inlet temperature is best controlled at 170~190℃, and the bed temperature is controlled at 210℃. The heating process strictly controls the heating rate (≤25℃). (3) Airspeed. The temperature-raising reduction reaction of the C307 copper-based catalyst is a strongly exothermic reaction with a large space velocity, which can take away a large amount of heat and effectively avoid an increase in bed temperature. In order to control the temperature of the bed, the larger the airspeed, the better, but it is limited by the system pressure. The actual circulation volume of the reduction process is 240000~270000m3/h, and the actual airspeed is 5100~5800h-1. (4) Gas composition. Control the composition of reducing gas and strictly control the volume fraction of (CO+CO2) in the gas