Waste heat boilers are widely used in high energy consumption industries. There are two common types of waste heat boilers: one is used to recover the exhaust gas emitted by ordinary boilers, such as fuel fired and gas-fired boilers, biomass fired boilers, etc. The temperature of the exhaust gas from ordinary boilers is about 600 ℃, which is not too high, Therefore, the requirements for waste heat recovery boiler are relatively low. Beijing Energy saving steam generator The other is industrial waste heat recovery boiler, such as building materials industry, chemical industry, steel making industry, etc. The temperature of waste gas and waste heat in these industries is high, and the recovery and utilization are also quite valuable. small-scale Energy saving steam generator factory Henan Yuji Boiler Vessel Manufacturing Co., Ltd., founded in 2005, is located at No. 8, Jizhong Road, Xiaoji Town, Xinxiang County, Henan Province. It is a comprehensive enterprise of boiler and pressure vessel, mainly engaged in the manufacturing of boilers and pressure vessels, with technological innovation as the core, integrating the design, manufacturing, sales, installation, transformation and maintenance of boilers and pressure vessels.

The existing industrial boiler flue gas waste heat recovery equipment mainly includes tubular heat exchanger and full heat pipe heat exchanger. Tube and tube heat exchanger can be composed of finned tube bundles. The advantage of finned tube is that it can withstand higher temperature, but has low heat transfer coefficient and large floor area. Beijing Energy saving steam generator The flue gas of industrial boilers contains sulfur and other acidic substances. In the low temperature zone (flue gas outlet section), the temperature may be lower than the dew point of the acidic substances. The acidic substances will dew on the pipe wall, corrode the shell of the fin tube. The fin tube heat exchanger has poor operating reliability and low service life. small-scale Energy saving steam generator factory The total heat pipe heat exchanger of boiler flue gas waste heat recovery equipment is composed of heat pipe bundles. Its shell is made of multi-layer composite materials. The heat pipe structure is complex, the cost is relatively expensive, the service life is short, and the steel consumption is large. It is difficult for users to accept it, and it is difficult to promote its application in production. The composite heat pipe heater not only takes into account the heat exchange effect, but also takes into account the economic affordability of the investors in production, which is particularly suitable for the current situation in China's industrial production.

The furnace liner is the combustion chamber of the horizontal gas-fired heat transfer oil furnace. The burner nozzle is placed in the front of the furnace liner, and the high-temperature flue gas generated by combustion extends to the rear, leaving the furnace liner and returning to the space. Generally, the number of times of returning is not more than four, and the common one is the three return heat conduction oil furnace. Beijing Energy saving steam generator This type of heat transfer oil furnace can be divided into dry back type heat transfer oil furnace and full wet back type heat transfer oil furnace according to the structure of the flue gas reentry space at the rear of the furnace. The flue gas reentry space of the dry back heat conduction oil furnace is enclosed by refractory materials; The flue gas reentry space of the full wet back type heat conduction oil furnace is composed of a recuperative chamber immersed in water. In addition, there is a central regenerative heat conduction oil furnace: that is, the back wall of the furnace liner is sealed inside the boiler shell, and the flue gas is turned back to the front from the inner wall around the furnace liner after encountering. This type of heat transfer oil furnace can also be regarded as a full wet back heat transfer oil furnace. small-scale Energy saving steam generator factory Although the dry back heat transfer oil furnace is simple in structure, the refractory material at the rear of the furnace liner is easily damaged, and the rear tube plate is often directly washed by high temperature flue gas. The temperature difference is large, so the dry back heat transfer oil furnace is obsolete. At present, few manufacturers produce it; Although the full wet back heat conduction oil furnace has a complex structure, it avoids the problem of flue gas sealing in the reentry space and is suitable for micro positive pressure combustion.

When the boiler is shut down, the temperature of the heat transfer oil can be reduced to below 70 ℃ before the shutdown of the hot oil pump. In case of sudden power failure, extinguish the fire immediately, and then implement the operating procedures. Otherwise, the furnace tube will be burned out and the loss will be large. According to the type of heat transfer oil boiler, heat transfer oil shall be reasonably selected to prevent overheating. Beijing Energy saving steam generator When purchasing unqualified heat transfer oil, do not save money or mix heat transfer oil indiscriminately. Otherwise, the consequences will be very serious. Prevent the oxidation of heat transfer oil. The strict heat transfer oil is more than 50 degrees in contact with the air, which will make the heat transfer oil crack. Its speed is amazing, and the consequences are relatively serious. After normal operation, the test crew needs to close the exhaust valve on the auxiliary exhaust pipe. After 6 months of use, the heat transfer oil must be sampled and tested according to the instructions. If problems are found, the heat transfer oil must be replaced immediately. small-scale Energy saving steam generator factory However, it should be noted that different types of heat transfer oil should not be mixed. The circulation speed of the heat transfer oil should not be less than 1.5m/s. Due to the excessive temperature difference between some entrances and exits, the original design requirements were destroyed, the heat transfer oil could not maintain the original circulation state, the boundary layer became thicker, and the thermal resistance became larger, making the furnace wall exceed the oil film temperature, leading to carbon deposition, cracking, polymerization, coking, and even burning through the furnace tube.

System oil drainage: drain the heat transfer oil in the system when the circulating heat transfer oil is between 120 ± 5 (if the oil is not replaced, please find a clean container for proper storage) Prepare an appropriate amount of coke removal cleaning agent for the heat transfer oil system, drain the oil in the gas-fired heat transfer oil boiler system, and disconnect the cleaning system from the oil storage tank (close the valve), including the connection between the high-level tank and the oil storage tank. Beijing Energy saving steam generator Residual oil blowing steps: connect the air compressor at the pressure gauge or other places that can be connected, boost the system to 0.3-0.4MPa, and discharge it instantaneously; Repeat this process until the residual oil is blown out. The gas-fired heat transfer oil boiler, circulating pump, and other heat users form a cleaning circulating circuit for decoking and cleaning: add diluted cleaning agent to the system and fill it up to 1/2 of the water level of the high-level tank. Dosage of coke removal cleaning agent: 10~20%, the specific dosage shall be determined according to the scale thickness. Temperature: 90-95, time: 12-72 hours, which can be determined according to the scale thickness. Rinsing and cleaning: after cleaning, drain the residual liquid in the system and add clean water to rinse twice until the coke remover is free of foam and the water is clear. small-scale Energy saving steam generator factory Temperature: 85-95, time: 5-8 hours Water blowing steps: after cleaning, connect the air compressor at the pressure gauge or other places that can be connected, use compressed air to boost the system to 0.3-0.4 MPa, and vent at each low point. Repeat this process until the water is blown out. Waste liquid treatment: the cleaning waste liquid generated in the cleaning process is discharged after being treated in the biochemical tank.