Transferring fluids by means of a pump

Evander Mine- Chemical Handling- The safe Handling of Chemical Reagents Transferring fluids by means of a pump

The chemical handler will be required to operate a pump in the course of his duties. This could be for the purpose of transferring chemicals or to dispose of spillage.

In order to move a fluid from one point to another, use is made of pumps, either singularly or in series.

The pump required to perform this task could be a centrifugal pump or a positive displacement pump.

It is important that the fluid is delivered without spillage or waste.

Fluid is moved through a system of pipelines and valves, generally from a tank or vessel to another tank or vessel, or another process.

A positive displacement pump is very widely used for various applications.

Various positive displacement pumps are commonly used, but the most popular pumps used on our plants are peristaltic pumps, air-driven pumps and Moineau pumps.

A fluid is anything that is liquid enough to flow within a pipe, for example pulp, water, oil or reagents.

Most Metallurgical processes cannot function without a pump in the system.

Different pumping tasks require different pumps.

The selection of a pump is determined by the following:

Material to be pumped:

The viscosity of the fluid to be handled.
The density of the fluid.
The degree of corrosiveness of the fluid.
Lubricating properties of the fluid.
Stability of chemicals.
Whether or not the fluid contains solids in suspension.

Pump Specifications:

Volume required to be pumped.
The height the fluid should be lifted after it leaves the pump.
The total resistance that the piping system presents to the fluid flow.
Pressure at which the pump must deliver the fluid.
Kind of power supply needed / available.

Positive Displacement Pumps

Pump Starting and Stopping Procedures

[gem_list]Start Up and Shutdown Sequence (Centrifugal Pump)

Start Sequence

Operator identifies pump to be started.
Obtain clearance to start the pump.
Operator confirms that pump is ready to start.
Open gland service.
Check that gland service water pressure is satisfactory
Open flushing valve.
Close drain valve.
Start pump.
Run pump for ± ten seconds.
Open suction valve.
Close flushing valve after ± ten seconds.
Ensure that delivery valve is open.
Observe pump amperage to determine pumping efficiency.

Shutdown Sequence

Open flushing valve.
Close suction valve.
Flush for the pre-determined time (plant specific).
Stop pump.
Open drain valve.
Close flush valve.
Close gland service valve.

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Start Up and Shutdown Sequence (Peristaltic and Moineau Pumps)

[gem_list]Start Sequence

Operator identifies pump to be started.
Obtain clearance to start the pump.
Operator confirms that pump is ready to start.
Tank/sump levels are checked to determine that there is sufficient fluid to be transferred, and sufficient storage space at the delivery point.
The suction valve on the tank/sump is opened.
The pump is started.
Where applicable, the variable speed drive is adjusted to the required output.
The operation of the pump is monitored by way of amperage and fluid delivery.
Run pump for ± ten seconds.
Open suction valve.
Close flushing valve after ± ten seconds.
Ensure that delivery valve is open.

Shutdown Sequence (Positive Displacement Pump)

Stop the pump.
Close suction valve on tank/sump.
Check storage facility levels.
Observe pump amperage to determine pumping efficiency.

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