Doing a good job in boiler water treatment is one of the important links to ensure the safe and economical operation of industrial boilers.Due to the high combustion temperature of oil and gas.In addition, most fuel-fired and gas-fired boilers are small in size, compact in structure, and have high requirements for water quality. If the water treatment is not done well, it will cause scaling and corrosion of the boiler, which not only wastes fuel, but also easily causes accidents such as pipe blockage and pipe explosion. In severe cases, it will also cause the biggest economic loss of boiler scrapping.Therefore, oil and natural gas boilers must do a good job in boiler water treatment.
There are often a large number of impurities in natural water, among which the main influences on the boiler are: suspended substances, colloidal substances and dissolved substances.
Suspended matter and cavity matter are composed of mud sand, animal and plant remains and some low molecular aggregates, etc., which are the main factors that make water turbid.If these impurities enter the ion exchanger, they will pollute the exchange resin and affect the quality of the effluent. If they enter the boiler directly, the steam quality will be easily deteriorated, and it will easily deposit into sludge, block the pipeline, and cause the metal to be damaged due to overheating.Suspended and colloidal substances can be removed by pretreatment methods.
Dissolved substances mainly refer to salts and certain gases dissolved in water.Natural water, even seemingly pure tap water, contains various dissolved salts, among them calcium and magnesium salts.That is, the hardness material is the main source of boiler scaling.Since scale is very harmful to boilers, removing hardness and preventing scaling is the primary task of boiler water treatment, which can be achieved by chemical treatment outside the boiler or chemical treatment inside the boiler.
Oxygen and carbon dioxide in the dissolved gas that affect the equipment of oil-fired and gas-fired boilers are mainly oxygen and carbon dioxide, which will cause oxygen corrosion and acid corrosion to the boiler. At the same time, oxygen and hydrogen ions are also a kind of depolarizer with great effect, which will accelerate electrochemical corrosion. It is one of the important factors for boiler corrosion.Dissolved oxygen can be removed by deaerator or adding reducing drugs.For carbon dioxide, as long as the pot water has a certain pH value and alkalinity, its influence can be eliminated.
In addition, in some areas, the alkalinity of the water source is relatively high. After the industrial boiler is burned and heated and concentrated, the alkalinity of the boiler water will become higher and higher. After reaching a certain concentration, it will foam on the evaporation surface, affecting the quality of steam; under certain conditions If the alkalinity is too high, it will also cause alkaline corrosion such as caustic embrittlement at the stress concentration part.Therefore, alkali reduction treatment is required for water with high alkalinity.In addition, if the dissolved solids content is too high, it will also affect the quality of steam, and even cause co-evaporation of soda and water in severe cases.It should be controlled by reasonable sewage discharge.
In short, the purpose of boiler water treatment is to remove harmful impurities, prevent boiler scaling and corrosion, maintain good steam quality, and ensure safe and economical operation of industrial boilers.