dry vacuum pump in bulk drug industry

In the bulk drug industry, vacuum pump is mainly used in vacuum transfer, container vacuum, separation and drying of residual solvents in products. There are no special requirements for vacuum pump for vacuum transfer, container vacuum and other processes, only the equipment with reliable vacuum, less investment and other elements can be used; but for the separation and drying process of solvent residues in the product, there are higher requirements for the vacuum pump.

At present, the vacuum pumps used in product residual solvent separation and drying process in bulk drug industry are mainly liquid ring roots unit and dry pump roots unit. With the gradual improvement of national environmental protection and pollution discharge requirements and the increasing attention of enterprises to energy conservation and emission reduction and utilization rate of unit equipment, it has become a trend that roots units of dry pump replace liquid ring roots units.

According to the actual inspection of bulk drug manufacturers, the following advantages and disadvantages exist between liquid ring roots vacuum unit and dry pump roots unit

1. The dry-type vacuum pump does not need to use water as the circulating liquid, which avoids the use of circulating water and reduces the discharge pressure of water due to environmental protection treatment;

2. The cold hydrazine can be recovered in the front and back end of the dry vacuum pump, which can completely realize the recovery of solvent, improve the working efficiency of the pump, and make the exhaust gas meet the standard and directly discharge into the atmosphere;

3. In theory, the vacuum degree of dry vacuum pump is relatively high, generally 5 Pa, which is nearly 800 times higher than the limit vacuum degree of 4000 PA (under the condition of 10 degrees of circulating water) of water ring vacuum pump, which can effectively improve the separation and drying rate of products;

4. In terms of equipment energy consumption, the motor power of dry pump roots unit is smaller than that of liquid ring roots vacuum unit, and the energy consumption is low; the solvent content in condensate solvent mother liquor of dry pump roots unit is high, which is basically the same as that of wet product, while the solvent content in solvent mother liquor of liquid ring roots vacuum unit is about 12 ~ 30%, so the recovery cost is much higher.

5. As the front stage pump of roots pump, the higher the vacuum degree, the smaller the load of Roots vacuum pump (the front stage pressure of Roots vacuum pump must be less than 8000 PA), and the less heating, which greatly improves the service life of Roots vacuum pump; the actual vacuum degree of liquid ring vacuum pump is only -0.088 due to the solvent (10% ~ 30%) in liquid ring vacuum pump~- 0.09mpa, which can not meet the requirement that the front stage pressure of Roots vacuum pump is less than -0.092mpa. It is inevitable that the life of Roots vacuum pump is shortened due to heating. According to the actual test, the surface temperature of Roots vacuum pump can reach 110 ~ 120 ℃ and the service life is only 3 ~ 6 months, while the surface temperature of dry pump roots unit is 70 ℃ and the temperature of Roots vacuum pump is 60 ~ 70 ℃, which is far lower than that of liquid ring roots vacuum unit, and the service life is greatly improved, at least not less than 2 years The cost of nursing is also low.

6. The disposable input of dry pump roots unit is higher, which is about 2 ~ 3 times of liquid ring roots unit.

Features of installation and use:

1. In front of the vacuum pump, a washable metal sintering mesh filter is installed to effectively prevent dust from entering the vacuum unit, causing the unit to be stuck;

2. High efficiency condenser and vacuum condensate receiving tank are installed in front of the vacuum pump, and the vacuum control system is opened. When the vacuum degree is high, the high-efficiency condenser and vacuum condensate receiving tank stop working, and when the vacuum degree is low, it can effectively improve the pumping rate of vacuum pump and increase the separation and drying speed; it can condense 40 ~ 50% of the whole batch of solvent;

3. The installation mode of Roots vacuum pump is higher than claw pump, which can effectively ensure that roots pump does not accumulate liquid, and can effectively improve the life of roots pump;

4. The installation of the initial coagulation tank can effectively prevent the claw type dry pump from accumulating liquid, affecting the drying efficiency and the service life of the claw pump;

5. The installation of tail gas condensate receiving tank and tail gas high efficiency condenser can make the exhaust gas meet the requirements of environmental protection and realize the full recovery of solvent gas in tail gas;