In the pre-dehydration stage of the coal gas phase drying equipment, only the air inside the tank is heated
In the pre-dehydration stage of the coal gas phase drying equipment, only the air inside the tank is heated, and at this moment, the tank is in communication with the outside world. The dry hot air rapidly alters the original temperature field. Due to the relative movement of the airflow, heat exchange is enhanced, the temperature of the body rises uniformly, and the temperature gradient between the coil and the iron core decreases. When the furnace temperature reaches the set value, it can be considered that the pre-dehydration stage has ended.
The duration of pre-dehydration depends on the heat absorbed by the body and the heat dissipation area of the radiator. The detailed action process is as follows: The vent valve is opened, and the heat transfer oil pump and the heater are automatically opened respectively. The heat transfer oil begins to circulate and heat the vacuum tank. It radiates and heats the tank body through the heating tubes inside the vacuum tank, as well as through gas convection heating. When the temperature inside the tank reaches 60 to 65 degrees Celsius at a rate of 15 to 20 degrees Celsius per hour (this temperature is determined according to the process requirements), the pre-dehydration stage comes to an end.
When the core and coil of the coal gas phase drying equipment reach a certain temperature, the heat absorbed by the coil has significantly decreased, and a lot of heat energy is absorbed by the core with a larger heat capacity. At this moment, if the vacuum pump is turned on to create a certain vacuum degree inside the tank, the water on the surface and in the shallow layer will start to evaporate. Continuously increase the vacuum degree so that part of the evaporated water is drawn out of the tank, and the other part serves as a heat transfer medium to participate in heat exchange. Because the evaporation of water takes away some heat and the pressure inside the tank drops, the temperature of the vessel body will decrease. At this moment, there should be sufficient heat to make up for the heat loss and keep the coil in a new heat balance to maintain a normal temperature rise.
The vacuum oil injection equipment manufacturer explains that disassembly should follow the principle of handling with care and not be done carelessly. It is absolutely forbidden to strike with a sledgehammer. When cleaning parts, make sure they are clean and thorough to facilitate the identification of problems and potential dangers. Vacuum pump products are quite different from general mechanical products. While general mechanical products often have beveled edges and corners, vacuum pumps have distinct edges and corners, which can easily hurt hands. Extra care should be taken and this should be kept in mind. Inspection is a meticulous job. No detail should be overlooked, and there must be no mentality of taking chances.