The liquid ring vacuum pump is a suitable solution to extract steam. Such steam can corrode and decompose the former vacuum pump oil in chemical way or have such low vapor pressure so that condensation in the former vacuum pump can not be avoided, even though there is gas. However, they will only achieve the limit pressure determined by the vapor pressure of the working fluid.
If water at 15 ° C is used, the expected limit pressure of the liquid ring vacuum pump is about 20 HPA, and then it has been operated in the cavitation range. Cavitation occurs near the vacuum pump limit pressure. The working fluid evaporates at the inlet side, and the steam bubble suddenly bursts at the pressure side. This will damage the vacuum pump for a long time. The limit pressure achieved by the liquid ring pump with air supply and cavitation free operation is about 25 to 30hPa, and the limit pressure achieved by the combination of roots vacuum pump and liquid ring pump is about 1hpa. Liquid ring vacuum pump shall not be used together with fresh water when exhausting substances harmful to the environment.
In this case, a closed circulation system must be provided to push the appropriate working fluid through the cooled heat exchanger to extract the compressed heat.
Liquid ring vacuum pump with gas injection device
The combination of Roots vacuum pump, gas injection device and liquid ring vacuum pump can achieve the limit pressure of 0.2hpa. If a lower pressure is required, an additional roots vacuum pump must be connected upstream.
Liquid ring vacuum pump pipeline installation technology
1. The exhaust pipe of liquid ring vacuum pump or liquid ring compressor is connected with the intake pipe of gas-water separator. When used as liquid ring compressor, the exhaust pipe of gas-water separator is connected with the system using compressed gas. Generally, the pipeline shall not be too long and the turning shall not be too fast. When it is used as a vacuum pump, the gas is discharged to the atmosphere from the air outlet of the gas water separator. In order to improve the working environment, the gas can be discharged to the outside of the working place through the pipeline.
2, liquid ring vacuum pump pipe flange connection, the use of gaskets to make it reliable, especially the vacuum pump inlet air path slightly incoherent, it can not achieve a predetermined vacuum.
3. The intake pipe of liquid ring vacuum pump or liquid ring compressor shall be equipped with warehouse valve, so as to shut down the vacuum pump or liquid ring compressor before stopping, so as to prevent the water in the vacuum pump or liquid ring compressor from returning to the system under the pressure of the exhaust pipe. In order to facilitate the work, it is better to install a vacuum gauge between the air inlet and the valve, so as to check whether the vacuum work normally at any time. When the liquid ring vacuum pump is used as a liquid ring compressor, a gate valve shall be installed on the exhaust pipe of the gas-water separator, and a pressure gauge shall be installed between the exhaust pipe and the valve, so as to check whether the pressure of the compressed gas liquid ring vacuum pump reaches the required pressure at any time.