Gas steam boiler water quality problem
Doing a good job of water quality is one of the important links to ensure the safe and economic operation of boilers. Because the combustion temperature of oil and gas is high. Most of the fuel and gas boilers (especially imported fuel gas boilers) are small in size and compact in structure, and have high requirements on water quality. If the water treatment is not well done, boiler scaling and corrosion will be formed, not only the fuel but also the fuel. Causes blockages, squibs, etc., and in severe cases, will also form the largest economic loss of boiler scrap. Therefore, boilers for fuel and natural gas need to carefully handle boiler water treatment.
Basic knowledge of boiler water
1. Indications for damage to boilers in natural water and boiler water treatment
There are many impurities in natural water, and the main factors affecting the boiler are suspended matter, colloidal matter and dissolved matter.
Suspended matter and cavity materials are composed of mud sand, animal and plant remains and some low molecular aggregates, which are the primary factors that make water turbid. If these impurities enter the ion exchanger, it will contaminate the AC resin and affect the quality of the water. If it enters the boiler directly, it will easily deteriorate the quality of the steam, and it will easily accumulate into mud and block the pipe, causing the metal to be damaged due to overheating. Suspended and colloidal materials can be removed by pretreatment.
Dissolved matter primarily refers to salts and certain gases dissolved in water. Natural water, even in seemingly pure tap water, contains various dissolved salts, among which calcium and magnesium salts. That is, the hardness material is the primary source of boiler fouling. Because scale damages the boiler extremely, removing the hardness and avoiding scaling is the primary task of boiler water treatment, and can be reached by chemical treatment outside the pot or dosing in the pot.
The main factors affecting the fuel gas boiler equipment in dissolved gas are oxygen and carbon dioxide, which will cause oxygen corrosion and acid corrosion to the boiler. Together with oxygen and hydrogen ions, it is still a highly effective depolarizer, which will accelerate the electrochemical. Corrosion is one of the important factors in the corrosion of boilers. Dissolved oxygen can be removed by means of a deaerator or by participating in a restorative medicine. With regard to carbon dioxide, it is only necessary to adhere to the pH and alkalinity of the pot water to eliminate its effects.
In some other areas, the alkalinity of the water source is relatively high. After the fuel gas-fired boiler is incinerated and heated, the alkalinity of the pot water will become higher and higher. After reaching a certain concentration, it will foam on the transpiration surface, affecting the steam quality; Under certain conditions, if the alkalinity is too high, alkaline corrosion such as caustic embrittlement at the stress collecting portion may occur. Therefore, the alkalinity of the water quality needs to be reduced. In addition, the dissolved solid content is too high, it will also affect the quality of steam, and even cause steam and water to rise. It should be handled by reasonable drainage.
The intention of the boiler water treatment is to remove harmful impurities, avoid boiler scaling and corrosion, ensure steam quality and ensure safe and economic operation of the boiler.