Should a high-temperature hot water pump be set to automatic mode?
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One day, several pumps at a certain company, including a high-pressure coal slurry pump, suddenly stopped working. The high-temperature hot water pump also was not functioning properly; attempts were made to start the backup pump manually, but this proved difficult due to the high pressure – the valves couldn’t be turned, and cavitation occurred once the pump started operating. Disabling automatic mode may affect the pump in use; without it, it is difficult to start the pump during critical moments, and cavitation is likely to occur. What should I do? :(
High-temperature hot water pumps are not recommended to be equipped with automatic start functions, as they are high-pressure devices
Just by looking at the name of the pump, it can be seen that this is Northwest Research Institute’s multi-material slurry technology pump; a high-temperature hot water pump is also known as a high-pressure ash water pump. GE refers to it as a scrubber tower feed water pump. Generally, such pumps can be equipped with an automatic start function or not, depending on the configuration of the valves and the available personnel. If the outlet valve is electric, I think an automatic start function is not necessary; if the valve is manual, then an automatic start function should be considered. Other factors to take into account include the number of available personnel and whether the location of the valves facilitates easy operation.
This device is generally not set to automatic mode; it requires a one-way valve that can be used under graywater conditions to be absolutely reliable, which is actually impossible to achieve. Moreover, this pump has high power and is usually equipped with a high-pressure motor, to prevent sudden startup from putting strain on an unprepared power grid; conservatively speaking, it does not start on its own.
We also use technology from the Northwest Research Institute; our device is called a deaeration water pump. It uses 5-stage centrifugal pumps manufactured by Dalian Shenlan, with a voltage of 10,000V. During normal operation, if it doesn’t start within ten minutes after power is supplied, the power is automatically cut off, which is why we haven’t installed an automatic start function.
The design includes self-starting interlocks, so there should be no problems with starting it; the only thing is that the starting current is slightly high, but it stabilizes quickly. With such a large power grid, starting a high-voltage motor won’t cause any significant fluctuations
Your voltage is so high; generally, high-power applications use 6000V.
That seems to be the term used in the four-nozzle process, right? Are you guys using the four-nozzle process? Is it the pump located below the high-temperature hot water tower? (In other words, what we commonly refer to as the high-flash unit; both GE and the Northwest Research Institute use heat exchangers for indirect heat exchange between high-flash gas and high-pressure gray water, while the four-nozzle design seems to involve direct heat exchange between high-flash gas and high-pressure gray water on the trays located at the upper part of the tower.) This type of pump is usually a multi-stage centrifugal pump with a very high head, exceeding 800 meters, and it also has a considerable power rating. Self-starting is difficult to achieve from an electrical perspective; therefore, self-starting functionality is not generally provided
It is likely a term used in the four-nozzle process of new-type gasification furnaces; such pumps generally have high power and are multi-stage pumps, and they usually do not come equipped with an automatic start function.