Membrane separation nitrogen generators are widely used in outdoor workshops, field stations and open industrial production environments, and low-temperature weather in winter is easy to cause equipment failure such as pipeline icing, water accumulation blockage and component low-temperature damage, affecting the stability and efficiency of nitrogen production. Scientific and standardized winter anti-freezing maintenance is the key to ensure the long-term stable operation of membrane nitrogen generators in low-temperature environments. The core of winter maintenance is to eliminate water and residual liquid in the equipment, prevent pipeline and component freezing damage, and adjust equipment operating parameters to adapt to low-temperature working conditions, so as to avoid production shutdown losses caused by low-temperature equipment faults.

Before the arrival of low-temperature winter, comprehensive pre-freezing inspection and maintenance should be carried out firstly. It is necessary to thoroughly drain the accumulated water in the air storage tank, filter cavity, cooling pipeline and gas circuit of the nitrogen generator, because the residual moisture in the equipment will freeze and expand at low temperature, which will block the gas circuit and even crack the precision pipeline and filter elements. The aging and damaged sealing rings and pipeline joints should be replaced in time to prevent cold air from entering the equipment and causing local low-temperature condensation. For outdoor deployed membrane nitrogen generators, thermal insulation cotton and electric tracing bands can be wrapped on the outer wall of the gas transmission pipeline and the shell of the pretreatment device to maintain the internal operating temperature of the equipment and avoid icing of the air pretreatment system.

In the daily operation and maintenance in winter, the operating frequency of the drain valve should be increased, and the automatic drain device should be checked regularly to ensure the timely discharge of condensed water. It is necessary to avoid long-term idle shutdown of the equipment; if the equipment needs to be shut down for a long time, all residual gas and liquid in the system must be completely drained, and the equipment cavity should be kept dry and closed. In addition, low temperature will slightly reduce the gas permeability of the membrane module, resulting in a slight decrease in nitrogen production efficiency. It is necessary to appropriately adjust the air intake pressure and operating flow parameters according to the ambient temperature to ensure stable nitrogen purity and output. Regularly clean the dust and frost on the equipment heat dissipation and ventilation holes to ensure normal heat dissipation of the equipment, avoid low-temperature frosting and blockage, and effectively extend the service life of membrane modules and the whole equipment.