What are the heating methods of mixing and kneading equipment?
(1) steam heating
Steam with a pressure of 0.4~ 0.6mpa is fed into the jacket of the mixing and kneading machine to heat the body and paste. The mixing and kneading temperature and production efficiency are affected by the steam pressure. For example, when coal asphalt with a higher softening temperature is used, a higher mixing and kneading temperature is required.
At the same time to solve the body and steam pipeline pressure problems.
Winter and summer even if the steam pressure is the same, using the same kneading time, winter kneading temperature sometimes can not meet the requirements, which must be extended kneading time.
(2) electric heating
Electric heating methods include resistance wire heating, power frequency induction coil heating and heating element heating.
The electric heating mixing and kneading machine has a fast heating rate and can reach the required temperature in a short time.
Electric heating mechanism is relatively complex, such as improper use, mixing temperature is easy to be high, resulting in local paste aging, electric heating element is also easy to damage.
The preheating of the dry material of the counter-current strong mixing and kneading machine is also heated by the electric current of the electrode plate.
(3) heat conduction oil
Heat conduction oil heated to a certain temperature and maintained a certain pressure flows in the jacket of the kneading machine, transferring the heat carried by the body to the kneading material.
The heat conduction oil shall be heated to the specified temperature in the reheating furnace. When the medium temperature asphalt is used, the heat conduction oil shall be heated to 180~210℃.
When adopting modified asphalt with higher softening temperature, it is necessary to raise the heat conduction oil temperature.
Generally, it is about 240℃.
The heat conduction oil heating temperature in winter is 50~60℃ higher than that in summer.
The advantage of using thermal oil is that the heating temperature can be raised at any time, and the thermal oil can be recycled.
(4) use the heat of dry material preheating and molten asphalt
There is no heating mechanism of counter-current type strong mixing and kneading machine itself, because the solid carbonaceous material has been heated to 170℃ in the resistance heater alone, the temperature of the molten asphalt is up to 180℃ or so, so as to reliable dry material preheating and the heat brought into the molten coal asphalt itself to kneading.
