In the evaporation operation, due to the different evaporation equipment and solution used, the fault handling methods are also different. The following is a list of common operating faults and handling methods of sodium chloride evaporator, so that you can be familiar with common faults and easily deal with them in case of faults!
1. The leakage of high-temperature corrosive liquid or steam often occurs in weak links such as sodium chloride evaporator and pipeline weld, flange, sealing filler, expansion joint, etc. The direct causes of leakage are mostly cracks caused by thermal expansion and cold contraction during startup and shutdown; Or the inlet becomes thinner due to pipeline corrosion, and breaks due to stress impact when opening or stopping, resulting in liquid or steam leakage. In order to prevent such accidents, sodium chloride evaporator inspection, pressure test, leakage test and regular inspection of equipment corrosion shall be carried out before use.
2. The pipeline valve is blocked. As for the solution that is easy to crystallize during evaporation, it often crystallizes with the thickening of the material, resulting in the blockage of pipes, valves, heaters, etc., making the material unable to flow, and affecting the normal evaporation of the sodium chloride evaporator. Therefore, salt mud should be separated in time and cleaned regularly. In case of blockage, use pressurized water washing or vacuum suction to remedy it in rainy days.
3. Troubleshooting for excessive temperature of sodium chloride evaporator
(1) It may be that the expansion valve is opened too large, and there is too much refrigerant entering the sodium chloride evaporator, which cannot completely evaporate in the evaporator. The excess liquid occupies a part of the heat transfer area, the heat transfer area is reduced, and the suction and evaporation temperatures are high. The opening of the expansion valve shall be properly adjusted according to the cooling capacity.
(2) The other possibility is that the condensation temperature is too high and the evaporation temperature is increased, because when the condensation temperature rises, the compression ratio of the compressor increases, the suction coefficient decreases, and the specific volume of the gas increases, resulting in an increase in the evaporation temperature.
4. Evaporation temperature is too low
(1) The expansion valve may be too small or blocked. So the refrigerant entering the sodium chloride evaporator is too small, and some heat transfer areas are not subject to refrigerant heat absorption and evaporation, and the discharged gas is not enough to meet the requirements of compressor suction. The specific volume of the gas in the sodium chloride evaporator decreases, the pressure decreases, and the evaporation temperature decreases. The standard is to properly adjust the opening of the expansion valve.
(2) The amount of refrigerant used to replace the liquid is insufficient, and the amount of refrigerant entering the sodium chloride evaporator is very small, resulting in the inability of heat exchange on some surface areas. The refrigerant entering the sodium chloride evaporator is easy to evaporate, but it cannot meet the suction requirements of the compressor, resulting in a drop in evaporation temperature. Refrigerant shall be added according to the amount specified in the design specification.
