In the late 1980s, domestic manufacturers developed a vacuum hot water boiler, but due to technical problems, it was mainly unable to solve the problem that the electrochemical reaction between water and iron in the sealed vacuum state of the boiler led to the continuous decrease of vacuum degree, and it has not been popularized. In 1990s, Korean manufacturers entered the China market relatively, and in 2003, domestic boiler manufacturers began to produce vacuum boilers. Vacuum boiler is a vacuum environment with negative pressure in a closed furnace body, which is filled with heat medium water. Heat medium water is heated by combustion or other means, and the heat medium water is heated to generate steam, and the steam heats the water in the heat exchange tube through condensation heat exchange, thus realizing the supply of hot water.
Schematic diagram of heat conversion of vacuum boiler:
Oil, natural gas, gas and electricity->; Combustion (heat of electric conversion)->; Heat medium water->; Heat transfer of steam condensation after boiling->; Heat exchanger->; Heat conduction->; water
Working principle of vacuum boiler: the low boiling point of water at low pressure is used to heat the heat medium water in the sealed furnace quickly, so that the heat medium water boils and evaporates high-temperature steam, and the steam condenses on the heat exchange tube to heat the cold water in the heat exchange tube, thus achieving the purpose of supplying hot water.
Standard sea level pressure:1.013×105pa =101.3kpa, and the boiling point of water is100℃; The higher the altitude, the lower the atmospheric pressure and the lower the boiling point;
Qinghai-Tibet Plateau: the average altitude is 4000m, the atmospheric pressure is 62KPa, and the boiling point of water is 87℃;
Mount Everest: the altitude is as high as 8848m, the atmospheric pressure is 33KPa, and the boiling point is 71℃;
Vacuum boiler creates a low-pressure environment with almost no air by vacuumizing, and then uses water to boil at low pressure (below atmospheric pressure).
The working principle of raw steam is to output heat through condensation and heat exchange between steam and water.
Corresponding table of boiling point and vacuum degree of water: vacuum degree (kPa) 0-31-54-70-81-89-94-97-99-1kloc-0/boiling point of water (℃).
The heat medium water in the vacuum boiler is highly pure water after special treatment such as deoxidation and descaling, and it is filled once before leaving the factory. When in use, it is closed in the unit (vaporization → condensation → vaporization), and it does not increase or decrease, so it does not need to be supplemented or replaced during the service life of the unit.
Therefore, the vacuum boiler will never be corroded by scaling, and its normal service life can reach more than 20 years, far exceeding the service life of ordinary hot water boiler 10 years. 1, electric vacuum hot water boiler has the advantages of corrosion resistance, no scaling and long service life.
2. Because the inside of the electric vacuum hot water boiler is a whole with a closed atmosphere, oxygen in the intermediate medium water will be separated out and discharged from the electric vacuum hot water boiler during operation, and the vacuum hot water boiler will not be oxidized and corroded for a long time.
3. The electric vacuum hot water boiler only needs to add a small amount of heat medium water at one time, which will not increase or decrease during operation, so there is no scaling problem inside the electric vacuum hot water boiler. The service life of the boiler is prolonged, which is 1.5~2 times of that of the common boiler.
4. The heat exchanger of electric vacuum hot water boiler is made of stainless steel tube, which is corrosion-resistant and has a design service life of over 15 years.
5. The electrothermal vacuum hot water boiler has reliable quality, reasonable price and perfect after-sales service, which is well received by users. 1, the vacuum hot water unit always runs under negative pressure, and there is no danger of expansion and explosion, so it has incomparable safety and reliability compared with atmospheric boilers and pressurized boilers.
2. Built-in stainless steel heat exchanger has high heat exchange efficiency and clean water quality.
3. The collector is arranged in the flue pipe, which increases the heat exchange effect and makes the structure more compact.
4, imported burner, efficient combustion, low noise and exhaust emissions, meet the requirements of national first-class regions.
5. The overall structure is square, and it is sprayed integrally, with compact and beautiful appearance.
6. A spiral spoiler is arranged in the flue to enhance heat transfer, improve boiler efficiency and reduce operation cost.
7. Indirect heating: the body is under negative pressure and the system is under pressure.
8. Large furnace lining technology: effectively increase the radiant heating area of the unit and reduce NOX emission.
9. The boiler uses high-purity water to ensure that the inside of the furnace body will never scale and corrode. 10. Integrated design of boiler and heat exchanger saves space and greatly reduces the floor space.
1 1, adopting the structure of pot-shell full-wet back tee, with dynamic heating and sufficient heat exchange.
12, the boiler operates at low temperature under negative pressure, which is safe and reliable.
13, fully automatic control system, no need to be attended by special personnel.
14, imported burner, high efficiency combustion, extremely low noise and exhaust emissions.
15, unique pulse water level detection circuit structure, reliable performance.
16, water temperature display function at inlet and outlet, which makes it easier to master the running state of boiler and system.
17, using advanced centrifugal glass wool multilayer insulation, less heat loss.