Hongda Cleaning - Evaporator Cleaning

Some regional environmental standards pose hazards to scaling.

When the actual operating temperature exceeds or falls below the ambient natural temperature, some heat exchangers require thermal insulation or cooling. The integrity of the insulation or cooling layer immediately affects the heat transfer characteristics of the heat exchanger. Should the insulation or cooling layer be damaged, changes in the environmental standards of certain areas can also accelerate the accumulation of scale, leading to the formation of scale layers.

Evaporator Cleaning

Hongda Cleaning - Evaporator Cleaning

Thermal exchanger's potential hazards to scaling during shutdown periods

Heat exchanger equipment should pay attention to the drainage pipes and maintenance during the shutdown period each year, as if the stored water or condensate inside the structure is not drained or cleared out completely, it may cause scaling when the equipment is relatively stationary. Therefore, especially during long-term shutdown, it is crucial to ensure proper drainage and maintenance of the heat exchanger.

Evaporator Cleaning

Hongda Cleaning - Evaporator Cleaning

Methods to reduce or eliminate scale formation

(1) Reduce and eliminate scaling standards from the perspective of design plans

The design of heat exchangers is based on calculating the total heat transfer area and relevant structural specifications to ensure the rationality of economic development for the required heat transfer purpose. During the architectural design, why not consider structural choices, such as, the cost of evaporator cleaning. Design can incorporate features that cause flow, and key heat exchange equipment can also be fitted with electronic descaling systems, reverse flushing systems, etc. If water is used as the heat transfer medium, under consideration of corrosion, anti-scaling additives and other materials should be used. Moreover, adhering to simple design principles can also reduce or eliminate external factors that cause scaling, such as: uncleaned and scaling-prone fluids should flow through the tube side, as tube side cleaning is very convenient.

Evaporator Cleaning

Hongda Cleaning - Evaporator Cleaning

After filling the cleaning tank with water and verifying that the system's circulation is normal, add an appropriate amount of detergent and begin the recirculating cleaning. According to the chemical cleaning process, check the concentration of the cleaning solution in the tank every 1 hour during the circulation. Maintain the concentration of the cleaning solution between 0.10 to 0.15 mol/L for safe and effective operation, and add detergent as needed based on the measurement data. If chemical cleaning requires more time and cannot be disassembled, a combination of recirculating cleaning and overnight soaking cleaning can be used. Evaporator cleaning

Hongda Cleaning - Evaporator Cleaning

When the concentration of the cleaning agent remains unchanged for consecutive 2 hours or changes minimally, the recirculation can be stopped. After the chemical cleaning rinse is complete, due to the small orifice size within the plate heat exchanger, there will always be scale and debris (especially dirt) adhering to the heat transfer plates. Therefore, the Guangzhou evaporator cleaning requires the use of a recirculation pump to repeatedly flush out the scale and debris. Drain the waste liquid from the cleaning tank, fill it with fresh water, and use the recirculation pump to rinse. Drain the wastewater, then repeat the rinsing process, continuously adding water and observing until no more scale and debris are discharged from the plate heat exchanger. Evaporator cleaning

Hongda Cleaning - Evaporator Cleaning

Neutralization and Passivation Treatment Neutralization involves neutralizing the residual acidic solution left in the cleaned equipment without corroding it; passivation forms an electron conductor film on the metal surface that inhibits the metal dissolution process. This film itself dissolves very slowly in the medium, thus keeping the anodic dissolution rate of the metal at a very low level. Since the chemical cleaning does not require disassembly and involves several sections of pipes connected to the plate heat exchanger, the heat transfer plates made of stainless steel do not require neutralization or passivation treatment. However, the pipes are made of steel, and after cleaning, the surface scale and rust are removed, revealing the steel's true nature. It is in a highly reactive activated state, prone to corrosion. Therefore, neutralization and passivation treatment are necessary to prevent secondary rusting. Evaporator Cleaning

Hongda Cleaning - Evaporator Cleaning

The Selection of Cleaning Agents The current selection of cleaning agents includes acid cleaning, which encompasses both organic acids and inorganic acids.

Organic acids primarily include oxalic acid, formic acid, etc.

Inorganic acids mainly include hydrochloric acid, etc. The heat exchanger is made of nickel-titanium alloy, and hydrochloric acid is used as the cleaning fluid. It is prone to cause severe corrosion on the plates, thereby shortening the service life of the heat exchanger. The most commonly used cleaning agent is 0.2% to 0.3% of melamine, mixed with 0.015% to 0.2% and 0.005% to 0.1% of ammonium sulfonate. The equipment, after being cleaned and flushed, can self-passivate in the air. Evaporator cleaning

Hongda Cleaning - Evaporator Cleaning

Through repeated testing, it has been found that formic acid is an excellent choice for cleaning fluid. By adding buffer and surfactant to the formic acid cleaning solution, the cleaning effect is enhanced, and the corrosion of the cleaning solution on the plates is reduced. Chemical testing of scale samples shows that formic acid can effectively remove scale adhering to the plates, while it has a low corrosive effect on the heat exchanger plates.

Also small. Evaporator cleaning

Hongda Cleaning - Evaporator Cleaning

The Basic Principle of Scale Removal: Acid solutions readily react with calcium, magnesium, and carbonate scale, forming easily soluble compounds and dissolving the scale. The Peeling Effect: Acid solutions can dissolve oxides on metal surfaces, used for power plant evaporator cleaning, disrupting the bond with scale and peeling it off the metal oxide surface, causing it to detach. The Gas Ejection Effect: After an acid solution reacts with carbonate scale, it produces a large amount of CO2. The CO2 gas, during its release, exerts a certain lifting force on the scale layer, which is difficult to dissolve or dissolves slowly, causing the scale to fall off the heat exchanger surface. Evaporator Cleaning

Power Plant Evaporator Cleaning - Hongda Cleaning (Online Inquiry) - Guangzhou Evaporator Cleaning is provided by Guangzhou Hongda Cleaning Co., Ltd. Hongda Cleaning Co., Ltd. boasts excellent service and products, consistently earning praise and trust from both new and old customers, as well as industry professionals. Our company is a member; click the icon on the page to chat directly with our customer service staff. We hope for a pleasant collaboration in the future!