Home > Exhibition > Content
Heat exchanger in the chemical production occupies an important position
Jun 15, 2017

Heat exchanger in the chemical production occupies an important position, and heat exchanger unit scaling corrosion, resulting in heat transfer is not enough and forced to stop cleaning or heat exchanger replacement, serious will affect the safety of production, but also increase the business operation the cost of.

1 particle dirt

The accumulation of solid particles suspended in the heat transfer surface, usually by the small particles of sediment, dust, insoluble salts, jelly, oil and other components.

When the water containing these substances flows through the surface of the heat exchanger, it is easy to form dirt deposits, the formation of scale corrosion, for some bacteria to survive and reproduce the breeding ground. When the anti-corrosion measures are not properly, eventually leading to heat transfer surface corrosion and leakage.

2 biological dirt

In addition to seawater cooling devices, the general biological dirt refers to microbial dirt. The most common microbes in circulating water systems are iron bacteria, fungi and algae.

Iron bacteria can be dissolved in water Fe2 + into water-insoluble Fe2O3 hydrate, in the water to produce a large number of iron oxide precipitation and the establishment of oxygen concentration corrosion of the battery, corrosion of metal.

And the algae in the circulating water system often forms a metal surface difference in the water to corrode the battery and cause corrosion under the sediment. The block will also block the pipe in the heat exchanger, reducing the flow of water, thereby reducing the heat transfer efficiency.

3 crystal fouling

In the cooling water circulation system, with the evaporation of water, the concentration of salt (such as bicarbonate) dissolved in water increases, some of the salt due to supersaturation and precipitation, and some salts due to heat transfer through the heat exchanger Surface heat decomposition caused by precipitation. These scales are composed of inorganic salts, crystalline dense, known as the crystallization scale.

3 Corrosion dirt

Corrosive fluids or fluids that contain corrosive impurities in the fluid to heat the surface of the heat transfer. The degree of corrosion depends on the composition of the fluid, the temperature and the pH of the fluid being treated.

Usually, the cooling tube in the cooling tube is generally copper and brass tube, metal corrosion is mainly higher temperature (40 ~ 50 ℃) oxygen corrosion, dirt to copper or copper alloy corrosion products and calcium and magnesium precipitates Mainly, resulting in a large number of corrosion dirt.

4 solidified dirt

Fluid in the subcooled heat transfer surface formed by the formation of dirt. Such as when the water is below the freezing point and solidifies into ice on the heat exchange surface. The uniformity of the temperature distribution has a great influence on this dirt.