A slurry pump is designed to move a mixture of liquid and suspended solid particles. Unlike pumps intended primarily for clean water, slurry pumps need to tolerate abrasive material and higher concentrations of solids.
Typical slurry applications include:
- Mining and mineral processing
- Tailings handling
- Mine-water pumping
- Construction-site sumps
- ETP and STP sludge handling
- Cement and concrete-related processes
- Ceramic and clay slurry
- Chemical slurry transfer
Flow Chem manufactures submersible agitator slurry pumps for applications involving settled solids and heavy slurry. Its current range is available from 2 HP to 15 HP, with models handling solids up to 60 mm and slurry concentrations up to 40% by weight, depending on the application and model.
Why Standard Water Pumps May Not Be Suitable for Slurry
Water pumps are generally designed around relatively clean or low-solids liquids. Slurry presents a different operating environment.
Depending on the application, slurry may contain:
- Sand
- Silt
- Mineral particles
- Clay
- Ore particles
- Sludge
- Abrasive solids
- Fibrous or mixed waste
These materials can settle around the pump intake, increase wear on hydraulic components and create blockages if the pump is not properly matched to the application.
For heavy slurry containing settled solids, an agitator-equipped pump can help re-suspend material before it enters the pump.
1. Understand the Slurry You Need to Pump
The first step in selecting a slurry pump is understanding the liquid-solid mixture.
Important information includes:
- Type of liquid
- Type of solid
- Solid particle size
- Solid concentration
- Particle shape
- Specific gravity
- Temperature
- pH and chemical characteristics
- Abrasiveness
Two applications may both be described as "slurry pumping" but require different pump configurations because the slurry characteristics are different.
2. Check the Slurry Concentration
Slurry concentration is one of the most important selection parameters.
A low-solids mixture behaves differently from a dense slurry containing a high percentage of suspended material.
High-concentration slurry can increase:
- Motor load
- Impeller wear
- Discharge resistance
- Settling risk
- Required torque
Flow Chem's agitator slurry pump range is designed for heavy slurry applications and is specified for concentrations up to 40% by weight, depending on the specific application and solid characteristics.
3. Consider Solid Particle Size
The maximum solid size must be considered when selecting the pump.
If the pump passage is too small for the solids present in the liquid, blockage and reduced flow can occur.
Before selecting a model, determine:
- Maximum particle size
- Typical particle size
- Particle shape
- Whether particles are sharp or abrasive
- Whether solids tend to settle
Flow Chem's agitator slurry pump models are specified to handle solids up to 60 mm, subject to the particular model and application.
4. Determine the Required Flow Rate
The required flow rate determines how much slurry the pump must move within a given period.
Flow is commonly specified in m³/hr or litres per second.
When determining the required capacity, consider:
- Average slurry flow
- Peak flow
- Required transfer rate
- Process capacity
- Number of pumps operating
- Standby pump requirements
Oversizing the pump unnecessarily can increase energy consumption, while undersizing can result in inadequate process capacity and excessive operating time.
5. Calculate the Total Head
The pump must generate sufficient head to move the slurry from the collection point to the discharge destination.
Total head can include:
- Vertical lifting distance
- Pipeline friction
- Valve losses
- Pipe fittings
- Discharge pressure
- Additional system resistance
Slurry characteristics can influence system resistance, so the hydraulic requirement should be evaluated using the actual application rather than assuming water-equivalent conditions.
6. Determine Whether You Need an Agitator
This is particularly important when solids settle at the bottom of a sump, tank or pit.
A conventional submersible pump may draw liquid from the surrounding area while settled solids remain at the bottom.
An agitator slurry pump incorporates an agitator that helps re-suspend settled material before it reaches the pump intake.
Flow Chem's agitator slurry pump uses an integrated agitator impeller to stir settled solids into suspension before the pump impeller draws the material in. This configuration is intended for applications such as STP desludging, ETP sludge handling, mining slurry and construction sumps.
7. Understand the Difference Between a Standard Submersible Pump and an Agitator Slurry Pump
| Feature | Standard Submersible Pump | Agitator Slurry Pump |
|---|---|---|
| Low-solids water | Suitable | May be unnecessary |
| Suspended solids | Depends on pump design | Designed for heavy solids |
| Settled solids | Limited ability to re-suspend | Integrated agitation |
| Heavy slurry | Application dependent | Designed for slurry handling |
| Mining slurry | Application dependent | Suitable for selected applications |
| STP/ETP sludge | Depends on sludge characteristics | Suitable for heavy sludge applications |
The correct choice depends on the actual liquid and solids characteristics, not simply the industry name.
8. Consider Abrasive Wear
Mining and industrial slurry can contain hard particles that gradually wear hydraulic components.
Abrasive slurry can affect:
- Impeller
- Wear plate
- Pump casing
- Shaft components
- Mechanical seals
For abrasive applications, pump construction and wear-resistant components should be evaluated as part of the selection process.
Flow Chem's agitator slurry pumps use cast-iron construction and a hardened wear plate for demanding slurry applications.
9. Check Mechanical Seal Protection
Mechanical seals are important in submersible slurry pumps because the pump and motor operate in or near the pumped liquid.
Abrasive particles can create additional challenges for sealing components.
When evaluating a slurry pump, consider:
- Single or double mechanical seal arrangement
- Seal-face materials
- Oil-chamber arrangement
- Compatibility with the slurry
- Expected operating hours
Flow Chem's agitator slurry pumps use double mechanical seals with an oil chamber to provide additional protection against abrasive slurry entering the motor area.
10. Select the Correct Motor Power
Motor power must be matched to the hydraulic duty and the characteristics of the slurry.
Higher slurry density can increase the power requirement compared with pumping relatively clean water.
Consider:
- Required flow
- Total head
- Slurry density
- Solid concentration
- Pump efficiency
- Operating hours
- Starting conditions
Flow Chem's agitator slurry pump range currently covers 2 HP to 15 HP, with heavy-duty motors intended for demanding slurry applications.
11. Consider Continuous-Duty Operation
Some mining and industrial applications require pumps to operate for extended periods.
For continuous operation, evaluate:
- Motor duty rating
- Motor cooling
- Seal protection
- Bearing arrangement
- Wear component life
- Thermal protection
- Maintenance accessibility
Flow Chem specifies Class F insulation and continuous S1 duty for its agitator slurry pump range.
12. Mining Applications for Slurry Pumps
Mining operations can involve several different pumping duties.
Open-Pit Mining
Open pits can collect groundwater, rainwater and water containing suspended soil or mineral particles. The pump selection depends on the amount and type of solids present.
Underground Mining
Underground sumps may collect water and sediment that must be transferred to higher elevations. Pump head, solids handling and installation access are important considerations.
Mineral Processing
Mineral processing can produce slurry containing abrasive particles. Pump selection should account for particle size, density, abrasiveness and operating conditions.
Tailings Handling
Tailings can contain high concentrations of fine mineral solids. The required pump configuration depends on slurry density, particle characteristics and transfer distance.
Flow Chem's mining pump range covers open-pit and underground dewatering, quarry operations, mineral processing and mine-construction applications.
13. Industrial Applications for Slurry Pumps
Slurry pumping is not limited to mining.
Potential industrial applications include:
- Effluent treatment plants
- Sewage treatment plants
- Chemical plants
- Ceramic manufacturing
- Cement-related processes
- Construction sites
- Industrial sumps
- Sludge transfer systems
Flow Chem specifically identifies STP desludging, ETP sludge handling, chemical plants, ceramics and cement, construction sumps and mining slurry among the applications for its agitator slurry pump.
14. Installation Considerations
Correct pump selection is only part of reliable slurry pumping. Installation should also be considered.
Review:
- Sump dimensions
- Pump submergence
- Discharge pipe diameter
- Pipeline length
- Guide rail arrangement
- Electrical supply
- Lifting arrangement
- Maintenance access
Guide-rail-compatible installation can be particularly useful in deep sumps because the pump can be removed for maintenance without requiring personnel to enter the sump. Flow Chem's agitator slurry pump is designed to support guide-rail auto-coupling arrangements.
15. Maintenance Requirements for Slurry Pumps
Slurry pumps operate in demanding conditions, so preventive maintenance is important.
Regular maintenance should include:
- Checking for unusual vibration
- Monitoring discharge performance
- Inspecting wear components
- Checking mechanical seals
- Inspecting electrical connections
- Checking motor insulation
- Cleaning accumulated solids around the pump
- Inspecting the discharge pipeline
If a pump repeatedly experiences clogging, reduced flow or rapid component wear, the issue may be related to pump selection, slurry characteristics or system design rather than maintenance alone.
Common Slurry Pump Selection Mistakes
Choosing a Pump Only by HP
Horsepower does not tell you whether the pump can handle the required flow, head and solids.
Ignoring Solids Concentration
A pump selected for low-solids water may not be appropriate for dense slurry.
Ignoring Particle Size
Large or irregular particles can cause blockage when the pump's passage is not appropriately sized.
Ignoring Abrasion
Highly abrasive particles can accelerate wear of hydraulic and sealing components.
Failing to Consider Settling
If solids settle rapidly in the sump, a conventional pump may not effectively remove the accumulated material. An agitator-equipped configuration may need to be evaluated.
Ignoring the Pipeline
A correctly selected pump can still underperform if the discharge pipeline creates excessive friction or the system head has been underestimated.
Slurry Pump Selection Checklist
| Parameter | Information Required |
|---|---|
| Application | Mining, STP, ETP, construction, chemical, ceramic, etc. |
| Liquid | Water, wastewater, process liquid or chemical mixture |
| Solids | Type, size, concentration and abrasiveness |
| Flow | Required m³/hr or LPS |
| Head | Vertical lift plus pipeline losses |
| Slurry concentration | Percentage by weight where available |
| Settling | Whether solids accumulate at the sump bottom |
| Agitation | Whether integrated re-suspension is required |
| Motor | Power, voltage, phase and duty |
| Materials | Required wear and chemical resistance |
| Installation | Sump depth, pipe size and maintenance access |
Why Application-Based Pump Selection Matters
There is no universal slurry pump for every mining or industrial application.
The pump should be selected after evaluating the complete duty:
- What liquid is being pumped?
- What solids are present?
- What is the maximum particle size?
- What is the solids concentration?
- How abrasive is the slurry?
- What flow is required?
- What head must be achieved?
- How many hours will the pump operate?
- Do solids settle in the sump?
- What materials and seals are appropriate?
Providing these details to the pump manufacturer can make model selection more accurate and reduce the risk of selecting a configuration that is unsuitable for the actual site conditions.
Why Choose Flow Chem for Slurry Pump Applications?
Flow Chem Pumps manufactures industrial submersible pumps in Gujarat and supplies solutions for sewage, wastewater, dewatering, drainage, cutter and slurry applications. The company states that it has been manufacturing submersible pumps since 2002 and operates an ISO 9001:2015 certified manufacturing facility.
For heavy slurry applications, Flow Chem's agitator slurry pump range combines an integrated agitator, open non-clog impeller, double mechanical seals and cast-iron construction. The current specifications include capacities up to 100 m³/hr and heads up to 20 metres, depending on the model.
Flow Chem also provides technical pump-selection support based on factors such as slurry density, solid size, flow, head and tank configuration.
Frequently Asked Questions
What is the best slurry pump for mining?
The appropriate pump depends on the mine-water or slurry characteristics, including flow, head, solids size, concentration and abrasiveness. For heavy slurry with settled solids, an agitator slurry pump may be considered.
What is an agitator slurry pump?
An agitator slurry pump is a submersible pump equipped with an integrated agitator that re-suspends settled solids before the pump draws them into the hydraulic passage.
What slurry concentration can a Flow Chem agitator pump handle?
Flow Chem currently specifies slurry concentrations up to 40% by weight for its agitator slurry pump range, depending on the specific model and solid characteristics.
What is the maximum solid size?
Flow Chem's agitator slurry pump range is specified for solids up to 60 mm, depending on the model and application.
Can slurry pumps be used in STP and ETP applications?
Yes. Slurry pumps can be used for suitable sludge and heavy-solids applications in STPs and ETPs. Flow Chem identifies STP desludging and ETP sludge handling among the applications for its agitator slurry pumps.
How do I select the right slurry pump?
Start with the slurry characteristics, then determine the required flow, total head, particle size, concentration, abrasiveness, operating hours and installation conditions. For heavy settled solids, also evaluate whether agitation is required.
Conclusion
Selecting the right slurry pump for mining and industrial applications requires more than choosing a motor size. The slurry's concentration, particle size, abrasiveness, flow, head and settling behaviour all influence the appropriate pump configuration.
For applications where solids settle at the bottom of a sump or tank, an agitator-equipped submersible slurry pump can provide an integrated approach to re-suspension and pumping.
To evaluate your application, review Flow Chem's Submersible Agitator Slurry Pump and Mining Pump solutions, or contact the Flow Chem team with your required flow, head, solids and slurry details.