Slurry refers to a mixture of liquid, usually water and oil, and solids such as sand, coral, sediment, and pulverized stone. Slurry is common in industries that do a lot of drilling, such as mining, waste water treatment, construction, and oil and gas drilling. To enable workers to continue with the project, the slurry must be pumped out through the use of slurry pumps. Slurry pumps are also used to transport solids hydraulically, such as those in a cement mixer truck.
The types of slurry depend on the area being drilled and the work being done. Slurry types have different flow properties that are influenced by the size, shape, density, and concentration of the particles as well as the density and viscosity of the liquid in which the particles are suspended.
How do slurry pumps work?
Slurry pumps are centrifugal pumps, which means it can rotate liquid using an impeller. The rotation of the slurry can control the particulates suspended in it. Some slurry pumps work to prevent solids from entering; some work to keep solids suspended; and some can effectively separate solids from the liquid they are suspended in.
The slurry pump’s basic structure comprises a high-pressure casing that usually has a semi-spiral shape. Inside it are different drive devices that work to turn a shaft and the pump’s bearing assembly. Along the shaft are impellers that are equipped with vanes that help create the necessary centrifugal force for spinning the slurry. When the pump’s drive devices are turned on, the bearings will do their job of keeping the shaft turning smoothly to allow the impellers to spin the slurry.
Types of slurry pumps
There are three main types of slurry pumps: horizontal, vertical, and submersible.
- Horizontal slurry pumps – Also known as dry mounted pumps, horizontal slurry pumps have their drive unit and hydraulic end outside the sump. Most slurry pumps fall in this category. These types of pumps make use of standardized seals and electrical motors.
- Vertical slurry pumps – Vertical pumps are further categorized into two: tank pumps and cantilever or sump pumps. Whereas horizontal pumps are dry mounted, tank pumps are dry installed. Its sump is already incorporated in the pump. Cantilever pumps are semi-dry installed because its hydraulic end can be lowered into the slurry, but its drive unit, as well as its support structure, are dry installed as in the tank pump.
- Submersible pumps – Submersible pumps are often considered as the most versatile among the three types because it can operate in the slurry directly and does not require a support structure. Both horizontal and vertical pump types are not waterproof, and flooding will easily damage the motor. This will never happen with submersible pumps.
A submersible pump does not need to be mounted on a dry surface and occupies less space overall. It has several installation options, making it flexible as well. The vertical and the horizontal pumps also make a lot of noise during operation; submersible pumps have less noise because these are underwater.
One of the best qualities of submersible pumps is greater reliability and efficiency. Being underwater, its motor is cooled by the surrounding slurry, so it does not overheat. If you are thinking of getting a slurry pump for your needs, a submersible pump is certainly the one to invest in.