The steam heater uses overheated steam as the heat source, so it is easy to leak and pollute the heating medium in the process of use. Therefore, the manufacturing requirements are strict and the cost of the equipment is relatively high; steam is used for heating, its price is cheaper than electricity, but it needs antifreezing in winter. From the perspective of operation, electric heating will not affect the regeneration of the adsorber due to steam leakage, so the cost of the equipment is relatively low.
Whether steam or electric heating is used for the heating and regeneration of the molecular sieve purifier is related to the equipment capacity and factory conditions. Generally, if the equipment capacity is relatively large and the factory has sufficient steam source, steam heating is usually adopted; if the equipment capacity is relatively small and the factory has difficulty in steam source, electric heating is adopted. Some also adopt steam heating first and then electric heating. Generally in normal production, steam heater is used for heating. When the steam pressure is insufficient or the molecular sieve needs to be activated, the electric heater should be put into use to increase the temperature of the heating medium.
The following problems should be paid attention to in regeneration operation:
1) no matter which kind of heating method, you should pay attention to the change of temperature curve of heating and cold blowing during the regeneration process of the adsorber. Description of abnormal changes of temperature curve:
① The regeneration heat source (steam or electricity) is insufficient or the gas volume is insufficient;
② If there is any change in the load of adsorber (especially the adsorptive water volume), the reason should be found out;
2) pay attention to the pressure change when the adsorber regenerates. If the pressure rises, it means that the resistance of the adsorber increases or the inlet and outlet valves of the adsorber are not closed tightly, the reason should be found out;
3) pay attention to the change of heating time. The extension of heating time should find out whether it is the heat source problem or the influence of the increased load of the adsorber;
4) note when operating the steam heater:
① Check the liquid level of condensate of steam heater frequently. High water level will affect the temperature of heat exchange;
② When the steam heat exchanger leaks, it will affect the effect of heating regeneration. Therefore, the moisture content of the gas after heat transfer should be checked frequently. Generally, the moisture content should be less than 1 × 10-6(Dew point temperature-65℃ ). Otherwise, check the working condition of the heat exchanger and handle it. There is usually a dew point detector behind the heater, and the change of dew point should be paid attention;
5) when using the electric heater, pay attention to that the heating medium flow should not be less than the requirement of process flow, otherwise the burning accident will occur. During cold blowing, pay attention to check whether the power supply has been cut off to prevent the electric heating components from burning out.
