THE COST OF NON-SELECTIVE CHEMICAL CLEANING OF HEAT EXCHANGERS

THE COST OF WORK ON THE OVERHAUL OF HEAT EXCHANGERS

Chemical washing of plate heat exchangers

During the operation of boiler installations, scale and other contaminants form on the walls of heat exchangers. They lead to the need to use more resources for the production of thermal energy, reduce efficiency and lead to premature failure of boiler installations. To solve the problem, the washing of heat exchangers using special chemical compositions is used.

It is carried out in two ways, depending on the design features of the heat exchanger. So, flushing can be carried out without disassembling the heat exchanger into parts, in more complex cases, disassembly of the system into parts and subsequent flushing of individual elements may be required.Special chemical compositions are used for washing heat exchangers, which, upon contact with scale and other contaminants, form a chemical reaction.

To facilitate the process, a heat exchanger flushing unit is used, which feeds a chemical solution into the heat exchanger under pressure, and then allows the internal surfaces to be flushed with water. The heat exchanger flushing unit used is necessary for heat exchangers with different operation and operation characteristics.

In order for the flushing of plate heat exchangers to allow cleaning the inner surfaces of the heat exchanger, it is necessary to select the chemical composition based on what kind of plaque has formed inside the heat exchanger. At the same time, for washing heat exchangers, it is necessary to use those compositions that cope with all contamination and at the same time do not destroy the internal parts of the heat exchanger. Aggressive chemicals can cause cracks to form on the walls of the heat exchanger.

To reduce the cost of heat energy production, it is necessary to systematically maintain the internal surfaces of plate heat exchangers using chemicals intended for this purpose. Reacting with plaque and rust inside, the chemical composition makes it possible to clean the walls, increase efficiency and extend the service life of the plate heat exchanger. Depending on the intensity of operation of the thermal installation, the characteristics of the water, it is necessary to resort to the procedure more often or less often.

Features of chemical washing of heat exchangers

Before carrying out chemical washing of heat exchangers, water is drained from the internal circuits of the heat exchanger through the drain valves. Then the chemical composition is prepared for injection, which is injected under pressure or with the help of improvised means. To achieve the greatest effect, it is carried out with the help of brushes that can be used to clean the inner surfaces.

High-quality work includes the use of a special chemical that reacts with sediments on the walls, dissolves them and allows them to be brought out. At the same time, chemical washing of heat exchangers may include the use of several chemical compositions, depending on the degree of contamination of the inner walls.

If the chemical solution is fed inside under pressure, the greatest effect can be achieved. At the end of the procedure, the liquid and dissolved precipitates are washed out of the heat exchanger, before starting the installation, it is necessary to flush the internal elements with running water.

In difficult cases, chemical washing of heat exchangers is carried out after their complete disassembly into separate parts. In this case, it is carried out using the same chemicals and brushes separately, then the parts are washed, and the design of the heat exchanger is assembled and connected to the boiler system. Some chemical compounds have a detrimental effect on the details of plate heat exchangers, reducing their strength. Therefore, it is recommended to use those compositions that have been approved by the manufacturer of the heat exchanger.

High-quality cleaning fluids should not leave behind foreign odors, change the color of the water. When carrying out, it is necessary to take precautions, wearing gloves and a mask. After the procedure, it is necessary to test the operation of the heat exchanger in a test mode, make sure that the plaque and other sediments are removed. Depending on the intensity of operation of the heat exchanger, its service can be carried out once a year, after the heating season or more often, depending on the intensity of pollution. When installing a new heat exchanger, it is possible to clean the internal cavities with water.

Flushing of heat exchangers

Carrying out scheduled flushing of the plate heat exchanger allows to increase the performance of heating, water supply, air conditioning and ventilation systems. The technology is quite simple and includes a number of the following sequential steps:

• Connection of the flushing pump.
• Preparation of the reagent solution with bringing to the desired concentration.
• Starting the pump in accordance with the operating requirements.
• Checking the effectiveness by monitoring the pH and gas emissions.
• Thorough flushing of the heat exchanger.
• Neutralization and disposal of used chemical liquids.
• Turning off the pump.

If the service has been met in full compliance with the requirements, the heat exchangers will regain their original properties and will be ready for efficient operation.

As practice shows, poorly maintained plate heat exchangers are contaminated with scale, rust, silt and various kinds of organic pollutants by 50 percent or more, which inevitably leads to a significant decrease in thermal efficiency and the amount of heat transferred from the coolant to the heated medium.