Pumps are the backbone of the process industry. In process plants, material needs to be moved from one point to another. According to the laws of thermodynamics, fluids are moved from areas of high pressure to areas of low pressure and, depending on the plant layout, the help of a pump is often required to achieve this. There are many different pump types available and choosing the right one can be tricky, especially when it comes to slurries.
This article will discuss some of the variables to consider when characterising slurries and selecting the right pump to move these slurries through the plant. It is not definitive and is by no means a complete review of handling slurries by pumping, but is intended to provide some useful information and a good starting point for considerations.
Ceramic Slurry Pump
Pumping slurries can often lead to blockages or equipment failure. It is the designer's job to assess all factors of each situation, including customer and existing site preferences, to design the system and select a pump that is robust enough to minimise clogging and make maintenance for the operator as easy as funds will allow, while providing a safe system of work.
Yi Jia Slurry Pump adopts a split shell design, which can easily overhaul the liner, impeller and sealing sleeve for maintenance. Most Slurry Pumps have an assembly auxiliary arm to support the suction sleeve when replacing the impeller and maintaining the gland. This feature allows technicians to remove the casing from the pump without having to drop the components on the ground or use a crane.
The term slurry is normally used to refer to a mixture of liquid and solids or a combination of solids. The liquid is usually referred to as the carrier fluid and in most cases is water, although it can be anything from an acid solution (e.g. nitric acid) to a hydrocarbon (e.g. diesel). It is beyond the scope of this document to produce slurries or maintain solids in suspension under static conditions.
Slurries can be broadly classified into two types: settled and non-settled slurries. This characterisation is based on the nature of the solids. Non-settling slurries contain solids consisting of fine particles that remain mostly in suspension when the applied mixing energy is stopped. Settling slurries, as the name implies, contain solids whose particles settle when the applied mixing energy is stopped. From a designer's point of view, it is important to understand the type of slurry. For example, non-settling slurries can be transported under laminar flow conditions, whereas settling slurries require turbulent flow conditions, especially in the horizontal section.
YAH Horizontal Ceramic (SIC) Slurry Pump
Slip conditions - when solids and carrier velocities are significantly different.
pipe size - ensure that the pipe internal diameter is much larger than the maximum particle size (6-10x 2 recommended)
pipe design (use of recirculation loops to ensure constant movement of slurry; use of waterfalls to allow slurry to be discharged to a safe point; use of long radius bends; installation of rods or flushing points; minimisation of bends; minimisation of dead ends; minimisation of suction pipes)
Hydrostatic head requirements; and available cavitation allowance.
Solid particles will play a key role in the selection of materials for the wetted parts. Amongst other things, the following should be considered.
Are the solids hard or soft? ie are they abrasive?
Does pumping the slurry cause erosion?
Are the solids corrosive? This applies to the carrier fluid.
If you want to get more information about the slurry pump selection, welcome to contact us today or request a quote.