In modern industrial processes, vacuum systems, as critical auxiliary equipment, are widely used in chemical, pharmaceutical, power, metallurgical, and environmental protection industries. As a highly integrated, closed-loop vacuum acquisition device, the reliability of the liquid ring vacuum pump directly affects the continuity and safety of the entire production line. Therefore, in engineering practice, a "one-in-one-backup" or "two-in-one-backup" pump set configuration is commonly adopted. This redundancy design is not simply about increasing the number of devices, but a strategic choice based on multiple dimensions of consideration, including process continuity, safety redundancy, and ease of maintenance.1. Ensuring Process Continuity and Avoiding Unplanned DowntimeMany industrial processes have strict and continuous requirements for vacuum levels. For example, in fine chemical reactions, vacuum is used to control boiling points, promote solvent removal, or prevent oxidation; in power plant condenser vacuuming, the vacuum level directly affects thermal efficiency. If the main pump suddenly fails and no backup pump is immediately put into operation, the system vacuum will be rapidly lost, potentially leading to runaway reactions, product quality defects, or even equipment damage. Employing a "one-in-one-backup" or "two-in-one-backup" configuration allows for automatic or manual switching to the backup pump in case of main pump failure, achieving seamless operation, minimizing production interruption risks, and ensuring stable process parameters.
2. Meeting Flexible Needs for High Loads and Fluctuating Operating Conditions
In some applications, the required pumping volume is not constant. For example, in batch distillation or batch drying processes, the initial gas load is high, which decreases significantly later. The "two-in-one-backup" configuration allows for flexible start-up and shutdown of the pump group based on actual load—dual pumps operate in parallel during peak periods to increase pumping speed, while a single pump maintains operation during off-peak periods, meeting dynamic needs while avoiding energy waste. Simultaneously, the backup pump provides an interface for future capacity expansion without requiring a complete reconfiguration of the vacuum system.
3.Enhancing System Safety and Adapting to Hazardous Media Handling
Liquid ring vacuum pumps are commonly used to pump flammable, explosive, toxic, or corrosive gases. In such high-risk conditions, equipment reliability is crucial for personnel and environmental safety. Failure of the sole operating pump not only leads to process interruption but may also cause hazardous gas leaks. Redundant pump configuration forms a critical safety barrier: even if one pump stops due to seal failure, impeller corrosion, or motor malfunction, the standby pump can immediately take over, maintaining system tightness and negative pressure to prevent the escape of hazardous media, conforming to the intrinsically safe design principle.
4. Facilitates Preventive Maintenance and Troubleshooting
Although the liquid ring vacuum pump has a simple structure and stable operation, it still requires regular maintenance, such as checking impeller clearance, cleaning heat exchangers, and replacing mechanical seals. In the "one in use, one standby" mode, maintenance can be performed on the off-duty pump without interrupting production, achieving "online maintenance." For the "two in use, one standby" system, even if one operating pump needs to be temporarily shut down, the remaining pump can still maintain basic vacuum capacity, providing an operational window for planned maintenance and significantly improving equipment availability and lifecycle management efficiency.
5. Supports Intelligent Control and System IntegrationThe liquid ring vacuum pump is typically equipped with a PLC or DCS control system, integrating sensors for pressure, temperature, and liquid level, and linked with automatic replenishment valves and cooling water regulating valves. In a redundant pump architecture, the control system enables intelligent rotation operation (balancing the usage time of each pump), fault self-diagnosis, automatic switching, and remote monitoring. For example, when the operating pump current is abnormal or the separator liquid level becomes unstable, the system can automatically start the backup pump and issue an alarm, achieving the automated goal of "unattended, safe operation."In summary, the "one-in-one-out" or "two-in-one-out" pump configuration embodies the comprehensive optimization of liquid ring vacuum pumps in terms of reliability, safety, flexibility, and intelligence. It is not only an equipment redundancy strategy but also an essential requirement of modern industry for continuous production, risk control, and efficient operation and maintenance. With the support of technologies such as closed-loop circulation, closed-loop cooling, and automatic control, this configuration further amplifies the application value of liquid ring vacuum systems under complex operating conditions, becoming an indispensable vacuum solution in high-end process industries.
