Dry screw vacuum pump in industry

In the face of the continuous promotion of market competitiveness and the development of its advantages and capabilities in all aspects, it is necessary to increase the promotion of its advantages and capabilities in all aspects according to the actual characteristics of the dry screw vacuum pump, with reliable product application strength, according to the effective play of the overall application strength, to enhance the continuous improvement of its application advantages in all aspects, and with reliable product application effect to promote the actual performance The development reflects the effective play of the overall application performance, so as to increase the overall promotion of all aspects of application advantages. So, what is the application of dry screw vacuum pump in industry?

What are the industrial applications of dry screw vacuum pump? There are mainly three aspects, as follows:

1、 Dry screw vacuum pump for solvent recovery in pharmaceutical industry

Bulk drugs selected from solvent crystallization methods are usually filtered after crystallization, washing and vacuum drying. The moisture content of the material is usually between 20% and 200%. The solvent contained in the wet material is usually flammable, explosive, toxic and harmful medium, which is evacuated during drilling.

Traditional wet vacuum system uses roots liquid ring vacuum pump. The sealant of liquid seal pump dissolves or absorbs part of organic solvent during operation, and separates waste gas and high concentration organic waste liquid in vapor-liquid separator. Some of them need to be dealt with. This will not only not completely recover this part of solvent, but also increase the operating cost of the company, bringing health, safety and environmental protection to the battle; the dry vacuum condensation system can discharge organic solvent in the boring process. As there is no other process medium in the cavity of screw pump, coating anti-corrosion method is adopted inside, which is energy-saving and environmental protection, so side condensation, complete solvent recovery, zero discharge of waste liquid. There is no waste disposal problem and the solvent can be completely recovered. Therefore, screw vacuum pump has become the best choice in this field.

2、 Application of dry screw vacuum pump in gasoline vapor recovery of petrochemical industry

Dry screw vacuum pump is the key equipment of gasoline vapor recovery equipment. The gas pumped is simply vaporized gasoline vapor. The main components are gasoline vapor, such as C4, C5 and C6.

Generally, the working temperature of the vacuum pump is controlled below 80 ° C. However, by relying on jacket jacket cooling, pump cooling cannot be reduced to such a low temperature. Most stations do not have cooling water. The coolant available is gasoline. In order to reduce the working temperature of the pump, in addition to introducing gasoline into the jacket of the pump body, the most useful method is to inject appropriate amount of gasoline into the pump chamber (at the highest temperature) to evaporate heat absorption to reduce the temperature in the pump chamber.

Because the screw vacuum pump is in the process of oil vapor recovery, the condensed gasoline will accumulate in the exhaust port of the pump. This accumulation will cause abnormal vibration and noise of the pump, so it must be discharged in time. Methods of improvement.

1. The exhaust pipe of the vacuum pump inclines downward, and the direction of the exhaust pipe is lower than the direction of the pump exhaust port.

2. Install circulating pump at the exhaust port of vacuum pump or the lowest point of muffler to eliminate liquid accumulation.

3. A check valve shall be installed at the exhaust port of the vacuum pump to prevent the condensate from flowing into the pump cavity due to siphonage during the shutdown.

3、 Application of dry screw vacuum pump in space imitation

As the volume of the space simulated pumping vessel varies from several thousand cubic meters to tens of thousands of cubic meters, the vacuum degree changes from tens of thousands of PA to several PA, and the pumping gas contains a lot of water vapor or a part of nitrogen oxide, the first problem encountered by this vacuum system is the pre vacuum problem. If a conventional spool valve is used as the front stage pump, the following problems exist:

First, the spool valve operates for a long time at high inlet pressure. Because of the air flow effect, fuel injection is very serious. One is to destroy a lot of expensive oil, the other is to pollute the environment;

As the pumped gas contains a lot of water vapor or nitrogen oxides, once the gas enters the pump, the vacuum pump oil will emulsify and deteriorate, the oil seal will be damaged, the vacuum function will be reduced, and the pump will be destroyed.

The number of pumps required by the equipment is large, and the vibration and noise of the valve core pump are also large; the screw vacuum pump has the advantages of clean and oil-free, large pumping speed, small vibration and low noise, which has become the first choice of large space simulation vacuum system. In addition, in order to improve the pumping speed and limit vacuum degree of vacuum device and reduce the size of screw pump, two-stage unit or two roots pumps and dry-type screw vacuum pump as well as roots pump and screw vacuum pump are usually used. A three-level unit consisting of three series connections. In order to prevent particle impurities from entering the pump, the inlet of the vacuum device is equipped with an inlet filter with an accuracy of 50 μ M.