How to deal with scaling of spiral plate heat exchanger? Can it be avoided?

Spiral Plate Heat Exchanger is a type of heat exchanger. As a device that realizes heat transfer between two materials in industrial production, it has been widely used in the chemical industry. It is used in all aspects of the chemical industry and is an important part of chemical production. important auxiliary production equipment. However, the same faults often occur during the use of spiral plate heat exchangers. The cause of the faults is the very common scaling problem. The best way to solve the scaling problem of spiral plate heat exchangers is to strictly operate the process procedures and maintain good quality. Routine maintenance and regular cleaning. Until now, how to effectively prevent heat exchanger scaling has become the key to production.

For the two heat exchange media, if they are both liquids, they must flow in a counter-current manner in the flow channel of the Spiral plate heat exchanger. The so-called counterflow means that two liquids in two adjacent flow channels for heat exchange flow in opposite directions along the spiral flow channel. This can always maintain a certain temperature difference between the two fluid media, thereby achieving a very good heat transfer effect. .

For the two media for heat exchange, one is liquid and the other is gas, they must flow in a cross-flow manner in the spiral Plate Heat Exchanger, that is, the liquid flows in the spiral direction in the heat exchanger, while the gas flows along the spiral direction. The axial direction of the heat exchanger passes directly. This is mainly due to the characteristics of the gas. Gas generally requires large flow and low resistance, or some are used for steam condensation, so the gas is generally not allowed to flow in the spiral direction.

The main heat exchange materials constituting the spiral plate heat exchanger are mainly divided into two categories: carbon steel and stainless steel. In order to avoid the problem of corrosion and scaling, a detachable spiral plate heat exchanger made of stainless steel can be used.

Measures to deal with the scaling problem of spiral plate heat exchangers:

1. Timely replace the spiral plate heat exchanger with serious scaling to ensure the normal operation of production.

2. Clean the spiral plate heat exchanger with severe scaling. The most serious scaling problem in spiral plate heat exchangers is the cooling water channel, while the scale in the lean oil channel is relatively small. Therefore, it is important to clean the scale in the cooling water channel.

3. Flushing: Before pickling, open-flush the heat exchanger first to ensure that there is no mud, scale and other impurities inside the heat exchanger. This can not only improve the pickling effect, but also reduce the acid consumption of pickling. Pour the cleaning fluid into the cleaning equipment and then into the heat exchanger.

4. Pickling: Soak the heat exchanger filled with acid solution statically for 2 hours. Then continue the dynamic cycle for 3~4 hours. During this period, alternate positive and negative cleaning every 0.5h. After pickling, if the pH value of the acid solution is greater than 2, the acid solution can be reused.

5. Alkali cleaning: After pickling, use NaOH, Na2CO3, Na3PO4, and softened water to prepare a certain proportion, and use dynamic circulation to perform alkali cleaning on the heat exchanger to achieve acid-base neutralization and make the heat exchanger The plates no longer corrode.

6. Water washing: After alkali washing, rinse the heat exchanger repeatedly with clean softened water for 0.5 hours to thoroughly rinse the residue in the heat exchanger.

7. Record: During the cleaning process, the time of each step should be strictly recorded to check the cleaning effect. After cleaning, the heat exchanger must be subjected to a pressure test before it can be used.

In short, in the process of industrial production, heat exchanger scaling is a quite common phenomenon. In order to ensure the normal operation of production, it is necessary to increase management efforts, pay attention to the properties of heat exchange materials, clean them regularly, and reduce or avoid the occurrence of scaling as much as possible. If scaling occurs, cleaning and descaling must be carried out in time to restore the production efficiency of the production equipment. At the same time, keeping the equipment in good operating condition can also reduce energy consumption, extend the service life of the equipment, and reduce the occurrence of production accidents.