Differences in water treatment process conditions and operations in gas generator feed water lead to different water treatment effects, resulting in different amounts of various impurities in the feed water. existgas generatorDuring the heating and evaporation process, colloidal substances in the water will deposit to form scale. At the same time, the salts of Ca2+, Mg2+ and other ions in the water reach a supersaturated state due to evaporation concentration or metathesis reaction under heating conditions, and precipitate in the form of crystals and deposit on the metal surface, forming dense and hard scale. The dissolved oxygen in the water will also corrode the metal, causing the scale to contain a certain amount of rust products. Once scale forms in the furnace, it will cause the following hazards to the safe and economical operation of the gas generator:
1. Increase heat loss and fuel consumption.
The thermal conductivity of scale is only 1/50~1/80 of steel. According to domestic and foreign thermal engineering experimental studies, when there is 1mm thick scale in the furnace, 8%~10% more fuel will be consumed than when there is no scale. The thicker the scale on the heat transfer area of the generator, the worse the heat transfer efficiency and the greater the fuel loss, which greatly increases the operating cost of the generator. The substantial increase in energy consumption (fuel) will also lead to a substantial increase in the amount of smoke and exhaust gas emitted from the generator, which will increase environmental pollution.
2. Scale causes the heat transfer efficiency of the heating surface of the generator to decrease.
Decreased heat transfer efficiency can easily lead to local high-temperature overheating of the furnace metal and a decrease in mechanical strength such as tensile and compressive strength. In severe cases, the metal heating surface may undergo deformation, blisters, cracks, leaks and other failures, posing safety hazards. In severe cases, it may cause explosion accidents, resulting in heavy losses to people and corporate property.
3. Shorten the service life of the generator.
Scale will cause the working temperature of the generator water and fire tube to increase, which will intensify the oxidation and corrosion damage of the metal under the scale on the side of the generator water, thereby shortening the service life of the generator, increasing the maintenance cost of the generator, and causing the generator to be scrapped in advance.
4. The steam production of the gas generator decreases and the steam quality is affected.
