Is it necessary to clean the plate heat exchanger regularly?

In the special circumstances of the maintenance, but also regular maintenance. Because the plate heat exchanger is easy to assemble and disassemble, the maintenance is simple. According to the different situation in different ways can be used, if the device is not only the leakage, heat transfer system K decrease, can not open the heat exchanger, and the cleaning liquid to the equipment within the cycle number of hours in a closed system. There is no such condition on the spot, and when the equipment is dismantled or the fouling is not serious, the plate can be removed and washed with water.

First, the normal operation and maintenance

Maintenance of equipment, should be installed in accordance with the reverse sequence of heat exchanger.

The equipment used in the petroleum and chemical industry shall be regularly maintained according to the maintenance cycle.

If the medium in the equipment is flammable, explosive or corrosive medium, at least once a year.

In other industries, the use of plate heat exchanger, if there is no leakage, the best three years to maintain a.

Two, plate cleaning and protection

Keeping the plate clean is one of the important conditions to keep the high heat transfer coefficient. In the plate, the medium is moving along the flow channel narrow winding, even if the scale layer is not too thick, also will cause the flow changes, significantly influence the fluid movement, the pressure drop increases, heat transfer coefficient decreased, such as a sugar refinery using plate heat exchanger in heating water two times, because there is no good treatment the process of using only two months will flow blockage, cannot continue.

1, chemical cleaning method

In this method, a chemical solution is circulated through the heat exchanger to dissolve and discharge the dirt on the surface of the plate. This method does not need to open the heat exchanger, simplify the cleaning process, but also reduce the degree of cleaning labor. The chemical cleaning method is an ideal method because the corrugated sheet can promote the turbulence of the cleaning fluid and is helpful for the dissolution of the scale layer.

2, mechanical (physical) cleaning method

This method is to use the brush plate after the artificial scrub, so as to achieve the purpose of removing the surface dirt. Although this method is more direct, but the harder, thicker layer of dirt, not easy to clean.

3, comprehensive cleaning method

It is difficult to clean up the dirty layer with the above method. Synthetic method is to use chemical cleaning method to soften the scale layer, and then mechanical (physical) cleaning method to remove the dirt layer, in order to keep the plate clean.

4, cleaning matters needing attention

Chemical cleaning solution to maintain a certain flow rate, generally 0.8 ~ 1.2m/s. Its purpose is to increase the turbulence of the solution.

Different chemical cleaning liquid should be used for different fouling. In addition to the regular use of dilute sodium carbonate solution, 5% of the scale can be used in nitric acid solution. 5% of hydrochloric acid solution can be used in the production of soda ash. But do not use the chemical corrosion of the plate corrosion.

Stainless steel sheets are not allowed to be brushed with carbon steel brush during mechanical (physical) cleaning so as to prevent the corrosion of the plate. At the same time, the surface of the plate can not be scratched and deformed.

After cleaning, the board should be washed with clean water and dry.

Three, the characteristics of gaskets and replacement

As the application field of plate heat exchanger is expanding, there are different requirements for temperature, pressure and corrosion resistance for different mediums and processes. It is obviously impossible to use a "universal" gasket to fit all situations, and different materials should be used in different situations. The shape of the cross section of the common gasket is six edges. The common types of gaskets are natural rubber, chloroprene rubber, three ethylene propylene rubber, silicone rubber, fluorine rubber, asbestos fiber board, etc..

Plate heat exchanger gasket in use if the leakage, fracture, aging and other phenomena, to be replaced in a timely manner. Replacement shall be carried out in the following order.

Remove the old gasket. Note that there must be no scratches in the gasket groove when removing.

Using acetone, methyl ethyl ketone or other ketones solvent to remove the residue in the gasket.

Clean gasket and gasket with clean cloth or cotton yarn.

Apply the adhesive evenly to the gasket groove.

Clean the new gasket on the board.

The attached plate gasket should be put in the flat and ventilated place to dry naturally after installation.