Most people may already know something about flue gas waste heat recovery, because they have already explained a lot about it. In order to let you know the relevant knowledge of flue gas waste heat recovery, the following is a brief introduction to the two methods commonly used for recovery. Shanghai Waste heat boiler Two methods are usually adopted for flue gas waste heat recovery: one is to preheat the workpiece; The second is to preheat air for combustion support. The flue gas preheating workpiece needs to occupy a large volume for heat exchange, which is often limited by the operation site (this method cannot be used for furnaces that are used intermittently). vertical Waste heat boiler how much Preheating air for combustion support is a good method. It is generally configured on the heating furnace, which can also strengthen combustion, speed up the temperature rise of the furnace, and improve the thermal performance of the furnace. This can not only meet the requirements of the process, but also achieve significant comprehensive energy-saving effect.

The manufacturer of the pneumatic water tank shall hold the pressure vessel manufacturing license or registration, and have a sound quality management system and system. Shanghai Waste heat boiler The purchased parts of the equipment must have the product certificate and pass the entrance inspection before use. The pneumatic water tank, water pump unit, electrical components and other components of the three-dimensional elastic filler manufacturer's equipment shall be assembled and used after passing the inspection. The equipment assembled on site can be used to inspect the performance of the whole machine on site. The production license issued by the relevant department shall be held. vertical Waste heat boiler how much When selecting this product, requirements shall be put forward for the following items: equipment composition, equipment classification, equipment working pressure, equipment design flow, specification and quantity of air pressure tank, equipment data, and sanitary requirements. The overall structure of equipment, water pipe, gas pipe and electrical circuit shall be arranged reasonably, and the manufacturer of single hole mold aerator shall reserve space for device maintenance to facilitate operation. The pipeline of the equipment shall be equipped with a safety valve, and the opening pressure of the combined packing manufacturer shall not be greater than 1.1 times of the working pressure. The equipment shared by fire fighting and living (production) shall have a separate fire water outlet.

Diaphragm air pressure tank is an energy storage device composed of a steel shell and a rubber diaphragm liner. The rubber diaphragm completely separates the water chamber from the air chamber. When the water with external pressure fills the liner of the diaphragm air pressure tank, the air sealed in the tank of the diaphragm air pressure tank will be compressed. Shanghai Waste heat boiler According to Boyle's gas law, the volume of gas becomes smaller after being compressed, and the pressure increases to store energy. The expansion of compressed gas can press the water in the rubber diaphragm out of the tank. Diaphragm pressure tank is widely used in central air conditioning, boiler, water heater, frequency conversion and constant pressure water supply equipment. It can buffer the pressure fluctuation of the system and eliminate water hammer to stabilize the pressure and unload the load. vertical Waste heat boiler how much When the water pressure in the system changes slightly, the automatic expansion and contraction of the diaphragm air pressure capsule will have a buffer effect on the change of water pressure, which can ensure the stability of the water pressure in the system, and the water pump will not be opened frequently due to the change of pressure.

High heat exchange efficiency. The fusion rate at the contact is more than 95%, the contact thermal resistance is small, and the thermal conductivity is good. Low flow resistance. Shanghai Waste heat boiler Since H-shaped finned tubes are similar to square structures, after being assembled into heat exchangers, the tubes are divided into many small channels by fins, which has a certain uniform effect on the air flow. The air flow is similar to longitudinal downstream flow, and the air flow resistance is relatively small. However, spiral finned tubes have strong air flow disturbance, high turbulence, and large air flow resistance due to the directivity of the fins. Less ash. The flue gas contains fly ash, which is easy to deposit on the windward side and leeward side of the pipe bundle. The H-shaped fin tube bundle has the characteristics of uniform flow and downstream flow, so it is not easy to cause serious local ash deposition, and the fly ash can be taken away with the air flow in time. Therefore, compared with spiral finned tube heat exchanger, H-type finned tube heat exchanger has less ash deposition. vertical Waste heat boiler how much Small size and low weight. H-shaped finned tube has high area expansion rate, less ash deposition, and high heat transfer efficiency. When the heat transfer capacity is equal, the space occupied by the heat exchanger can be small. For reconstruction projects, the heat exchange area can be arranged as much as possible in the limited space to reduce the exhaust gas temperature, improve the waste heat recovery efficiency, or increase the maintenance space to facilitate maintenance.

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. Shanghai Waste heat boiler 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. vertical Waste heat boiler how much 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.

Effectively prevent and reduce low temperature corrosion of air preheater. Low temperature corrosion is caused by sulfur dioxide generated by combustion of sulfur in fuel. Shanghai Waste heat boiler Under the action of catalyst, sulfur dioxide is further oxidized to sulfur trioxide. Sulfur trioxide and water vapor in the flue gas generate sulfuric acid vapor, which greatly increases the dew point of the flue gas, condenses the sulfuric acid vapor on the flue gas side of the preheater tube wall, causing sulfuric acid corrosion of the preheater. The content of sulfur trioxide has a great impact on the corrosion rate of the preheater. The content of sulfur trioxide is not only related to the sulfur content in the fuel, but also related to the oxygen content in the flue gas. vertical Waste heat boiler how much Low oxygen combustion can significantly reduce the oxygen content in flue gas, greatly reduce the amount of sulfur dioxide oxidized to sulfur trioxide, reduce the dew point of flue gas, and effectively reduce the corrosion of preheater. Low oxygen combustion reduces the amount of flue gas. It can not only reduce the exhaust gas temperature, improve the boiler efficiency, but also reduce the power consumption of the forced draft fan and the wear of the heating surface.