Plate heat exchanger is a kind of heat exchanger formed by pressing thin metal plates into heat exchange plates with a certain corrugated shape, and then fastening them with frame plates and bolts after stacking. The plate heat exchanger is characterized by its light weight, small footprint, low investment, high heat exchange efficiency, flexible assembly, and easy removal of fouling. Because of its small circulation cross-section, it is easy to cause blockage after scale, which reduces the heat exchange efficiency of the machine. The specific steps of plate heat exchanger cleaning scale.
(1) Chongxian. Open flushing of the plate heat exchanger so that there is no impurities such as mud and scale inside the heat exchanger. Countercurrent flushing is used during exercise or when the machine is stopped for a short time. It is not necessary to disassemble the device. This method is more effective when the fouling is not serious. Different rotating water gun heads are used for different plate heat exchangers, and the pressure can be adjusted freely. The use of high-pressure water to remove dirt is suitable for pipes, pipes and shells. The flushing effect of the high-pressure water gun is better.
(2) Pour the cleaning liquid into the cleaning equipment, and then pour it into the heat exchanger.
(3) Pickling: Please statically soak the heat exchanger filled with acid solution. After pickling, the pH of the acid solution is greater than 2, and the acid solution can be reused. Otherwise, the pickling solution should be diluted, neutralized and drained. The carbonate scale is acid washed.
(4) Alkaline washing. After pickling, please use sodium hydroxide, sodium, polonium, and demineralized water in proportion to prepare the heat exchanger in a dynamic cycle to achieve acid-base neutralization, so that the plates of the plate heat exchanger are no longer corrosion. Alkaline washing can also be used for sulfate and silicate scale.
(5) Wash with water. After the alkaline washing is over, please use clean demineralized water to rinse repeatedly to thoroughly rinse the residue in the heat exchanger.