In chemical production, the glass lined reactor with large length diameter ratio can be regarded as an ideal replacement glass lined reactor. It is suitable for both liquid phase reaction and gas phase reaction. It can be regarded as a constant volume process when it is used for liquid-phase reaction and gas-phase reaction without changing the number of moles before and after the reaction; When it is used for the gas phase reaction with the change of the amount of substance before and after the reaction, it is a volumetric process. If the temperature is basically kept constant during the reaction by appropriate adjustment means, it is a constant temperature process, otherwise it is a non constant temperature process. Non constant temperature operation in glass lined reactor can be divided into adiabatic type and heat exchange type. When the thermal effect of the reaction is small and the selectivity of the reaction is less affected by temperature, the adiabatic operation without heat exchange measures can be adopted. In this way, the equipment structure can be greatly simplified. At this time, as long as the reactant is heated to the required temperature and sent to the reactor. If the reaction process releases heat, the released heat will raise the temperature of the material after the reaction. If the reaction is endothermic, the temperature of the material gradually decreases with the progress of the reaction. When the reaction heat effect is large, the heat exchange type must be used to supply or remove the reaction heat in time through the overload heater. Most glass lined reactors use continuous operation, a few use semi continuous operation, and intermittent operation is extremely rare.