Choosing Dry Slurry Pumps Versus Submersible Slurry Pumps

The type of application will determine whether a dry or submersible pump solution should be installed; in some cases, a solution that combines a dry and submersible pump may be the best choice. This article outlines the benefits of submersible slurry pump versus dry mount pumping and shares some general rules that apply to both applications. Next, the slurry pump manufacturer  will share the following content with you.

Dry Installation

In dry installation, the hydraulic end and drive unit are located outside the oil sump. When using a submersible slurry pump for dry installation, the slurry pump must always have a cooling system installed. Consider the design of the water tank in order to deliver slurry to the pump. Agitators and side-mounted agitators cannot be used for this type of installation. 

Consideration should be given to installing mixers on guide rods in the catch basin/tank to keep solids in suspension and avoid settling in the catch basin/tank. When investing in a slurry pump, you want to pump slurry that includes solids, not just dirty water. Therefore, it is important to make sure that the pump is doing this; by using an agitator, the pump is fed with solids and pumping the slurry.

 Submersible Slurry Pump

Underwater installation

In a subsea installation, the slurry pump runs directly in the slurry and does not require a support structure, which means it is flexible and easy to install. If possible, the catch basin should be equipped with sloping walls to allow sediment to slide down into the area directly below the pump inlet. Agitators should be used when the liquid contains large amounts of solids and has a high particle density. Freestanding or side-mounted (submersible) mixers are an excellent choice for resuspended solids, especially if the catch basin is large or does not have sloping walls.

Mixers can also help agitators when pumping very dense particles. In applications where the tank is small and/or where pumping is desired to lower the water level in the tank, a slurry pump with an internal cooling system should be considered to avoid overheating of the stator (when the water level gets low). When pumping sediment from a dam or lagoon, consider the use of a raft unit, which is a submersible device. Agitators are recommended, as well as one or more mixers that can be mounted on the raft or pump to resuspend particles for successful pumping of particles.

Submersible slurry pump pumps offer many advantages over dry and semi-dry (cantilever) mounted pumps.

- Reduced space requirements - Since submersible slurry pumps operate directly in the slurry, they do not require any additional support structures.

- Easy installation - Submersible pumps are relatively easy to install since the motor and worm gear are a single unit.

- Low noise level - Operating underwater results in low noise or even silent operation.

- Smaller, more efficient tank - Because the motor is cooled by the surrounding liquid, the submersible slurry pump can be started up to 30 times per hour, resulting in a smaller, more efficient tank.

- Installation flexibility - The submersible slurry pump is available in a variety of mounting models, including portable and semi-permanent (also easy to move as it can be freely suspended from a chain or similar device without having to be bolted to the ground/floor, etc.).

- Portable and low maintenance - There are no long or exposed mechanical shafts between the motor and worm gear, which makes the submersible pump more portable. In addition, because there are no long or exposed mechanical connections between the motor and worm gear, less maintenance is required and operating costs are significantly lower.

- Lower operating costs - Typically, submersible slurry pumps require much lower operating costs than dry mounted pumps due to higher efficiency.