Mastering Slurry Pumps: Types, Applications, and Maintenance Guide

Slurry pumps are the unsung heroes of many industries. They tirelessly transport liquid mixtures containing suspended solid particles. These pumps handle challenging materials that would clog or damage conventional pumps from the depths of mines to the heart of power plants.

If you are looking for more details, kindly visit our website.

This guide explores the multifaceted world of slurry pumps, checking their types, revealing their many differing applications, and highlighting basic maintenance methods. Whether you are already a skilled professional or about to start your career, this article will provide enough material to build a solid base in this crucial area.

Related links:
Drip Irrigation Buying Guide - The Home Depot
When to Use Chlorine Dioxide Liquid？
Vibrating Table - Applied Vibration

If you want to learn more, please visit our website INDUX.

Conclusion: 

Slurry pumps, the workhorses of countless industries, play an indispensable role in numerous applications by efficiently handling challenging materials. From their diverse types and extensive applications to essential maintenance practices, this guide has equipped you with a solid foundation for understanding these vital tools. Remember, this information serves as a starting point. Consulting with a qualified pump specialist is highly recommended for specific applications and choosing the most suitable pump for your unique needs. By leveraging their expertise and implementing the practices outlined here, you can ensure the smooth and efficient operation of your slurry pumps, maximizing their performance and contributing to the success of your operations.

We are having some problems with an installation we just put in operation a month ago.
We are having some flow restrictions and we don’t know the cause.
We are pumping lime slurry (density gpl, temp about 60ºC).
The installation consists on a feeding tank, a centrifugal pump, a pipe ring, and 5 feed points with a control valve each one.
The tank is about 10 m3 capacity with an agitator.
The pump is centrifugal, with variable speed drive, rpm max, and 90 m maximum head. The vsd is controlled by the flow returning to the tank
The pipe ring is about 800 m – 4” to the feeding points, and 3” on the returning to the same feeding tank. We are pumping about 60 m3/h on the 4” line, and returning about 40 m3/h on 3”.
The feeding points have their own control valves and flow meter each one.
We have a pigging system to clean the line. The bends on the line are 10D radius, and the valves are ball valves full pass.
In normal operation the pump is working around 8barG on the impulsion, about rpm. But sometimes, the speed and the pressure starts to increase slowly, (let says, in 5 hours), and we it reaches the maximum speed (rpm, 10 barg) the flow returning to the tank starts to drop, and in a matter of 2-3 hours falls to nearly 0.
We haves some manometers on the feeding points, and with that and the % open of the valves, and the flow meters, we can see that there is no blockage on the 4” inches line.
So we are guessing that there is a blockage on the 3” line.
The thing that annoys me is that we have achieved a partial solution that consists on connecting a ½” hose to the pump suction and feed it with water.
As soon as we connect the hose, the flow stars to increase again, and in a matter of 20 minutes it reaches its normal condition and works properly.
His tends to happen by 2-3 times per week.
If is a matter of blockage on the 3” line, and the water helps to clean the line, why as soon we connect the hose the pump starts to increase the flow? The water would need about 20 minutes to run the 4” line and another 15” to return to the tank, so I suppose the should expected to have to wait about 30 minutes or more to see any improvement on the flow.
I am really lost with this, and any help would be appreciated.
It does sound like you are slowly plugging a line. The 4” line looks to be more likely the problem looking at the velocity. After the fourth or fifth feed point (depending on where you go to 3”) the velocity must be getting quite low in the 4” line. Slugs of slurry may be migrating to a point that they can slowly choke back the flow. As far as the garden hose getting things going it makes sense, for practical purposes liquids are not compressible and your system is a loop, liquid in will mean liquid out. You are diluting and possibly cooling the slurry also. There are many variables but velocity is very suspect with the symptoms you describe. Another possibility is that the liquid is a dilatant or pseudo-plastic and you are whipping up a creamy slurry or maybe just air trapped at the impeller eye.

Regards checman
If the pump has a enclosed impeller, it is possible to have a air lock in the impeller. I assume the lime slurry have a high tension between the air-liquid surface. The flush water can dilute the lime and reduced the surface tension, so the liquid brought the air away gradually.

If there is a high point in discharge piping close to the pump, there may be a air pocket there. with reduced surface tension, it can be gradually brought away by the liquid. However, this possibility is low except there is something special in the pipe.

It does not look like any blockage at the suction pipe since you never noticed any cavitation. At 60C temp and major blockage at suction line, I would expect serious cavitation. But it is possible that air accumulated at the reducer and then entered the impeller eye and locked the impeller. Dimtec,
You’re right, I wanted to say 4". Because I thought after the first feeding point Q will be reduced and you don't have 60 m³/h any more. That is getting worse close to the last feeding point.
option one- as I mentioned the problem is in the suction line ( more possible). By having Flexible Transparency Hose ( 4" ) as a suction line ( without any branch, bend, low point and so on. the problem will be solved. I saw the same problem many time in suction lines.
option two -Some companies use a flushing water connection with a solenoid valve. The valve gets open timely and flushes the line periodically.
Option three- if you have ant pressure/flow control on the recycle line such as back pressure control valve or flow orifice (FO is not a right application for this service)adjust them for lower presure and increase pump flow rate. by this you can increase the slurry velocity in the loop.

there is no scale issue. it's solid build up issue and may happen at low points, bends, branch connections, vertical points ....
Hope it does work.
Kavous

To check the discharge pressure is necessory and may give you answer to your questions.

There is unlikely solid settling in the suction pipe. 7fps velocity is pretty high for a 4" suction pipe. Even if some settling in the pipe, It's pretty easy to be brought away when the local velocity increased. I would prefer the reducer at the suction line top-flat instead of bottom flat because the bottom flat will make air bubbles accumulated at the top of the reducer.

To find out if there is air lock in the impeller or not, you can check the pressure gauge at the discharge pipe when the pump start to speed up. When the pump speed-up, the discharge pressure shall keep the same and when the pump reached max. speed, the discharge pressure starts to drop, so the recirculated lime reduced.