How to Select Clarifiers
Image Credit: Siemens Water Technologies
Clarifiers and screens are used to remove solids from liquids through gravity settling or a mechanical screening process. They are used to treat wastewater and purify drinking water.
Types of Clarifiers
The GlobalSpec SpecSearch database defines clarifier types by technology and categorizes individual products as conventional, sludge blanket, and suction type. Suppliers, however, may describe products by...
Learn More about Clarifiers
Q & A on Clarifiers
We asked our users for their input on Clarifiers. Here are the results of 48 users familiar with Clarifiers.
Who Took Our Poll? | Design Trends | Applications and Use | Features | Buying AdviceDesign TrendsTop
What new technologies are influencing clarifier and screen design?
7 answers
Lamelar or tubular clarifier with angle and backwash control.
~Process Engineer, Rivière-du-Loup, Canada
Plate settlers, tube settlers, upflow blanket clarifiers.
~John N, Research & Development, Hamilton, New Zealand
Flotation and screen filters
~Arnaldo R, Production Engineer, Lima, Peru
New environmental requirements are the #1 driving force. Arlat Technology has been working to improve controls for this equipment to make operations easier and more accessible with remote access capabilities.
~Jay C, Marketing/Sales, Walkerton, Canada
In India I do not see much of innovation, except that more compact designs are copied.
~Technical Support/Services, Chandigarh, India
Technologies that involve reduction of manpower and automation are of prime interest.
~Technical Support/Services, Alvarado, TX
Centrifuge machines such as decanter
~Ittidate Rujiwasin, Plant Engineering Manager, Bangkok, Thailand
From your perspective, which companies are creating the most innovative clarifiers and screens?
6 answers
FloTrend of Houston is one that comes to mind, but I have not tried a large variety of screens or clarifiers within the past 2 years.
~Technical Support/Services, Alvarado, TX
Arlat Technology / Can-Am chains
~Jay C, Marketing/Sales, Walkerton, Canada
Rotex
~Joseph G, Engineering Consultant, Tel Aviv, Israel
Hyndes
~John N, Research & Development, Hamilton, New Zealand
I observe that European and US companies are the most innovative in this aspect.
~Ricardo C, Process Engineer, Riyadh, Saudi Arabia
France and Switzerland
~Arnaldo R, Production Engineer, Lima, Peru
Applications and UseTop
What are some of the applications you have used clarifiers and screens for?
16 answers
We have used clarifiers (No screens)
(1) in water treatment systems for the fruit beverage industry
(2) in the post treatment of partially purified activated sludge sewage treatment plant effluent.
(3) Lamella type clarifiers in advanced treatment of chemical plant effluent.
~Engineering, Consulting, Caracas, Venezuela
In clarification of water & effluent. Screens generally at the entry points. In pulp & paper industry Pressure screens, vibratory screens are commonly used. (were part of our operational requirement)
~Technical Support/Services, Chandigarh, India
I have operated and maintained both clarifiers and screens in a mineral milling operation and also in various other plants.
~Technical Support/Services, Alvarado, TX
1. clarifiers - we use for primary and secondary treatment of sewage
2. screen - both coarse and fine screens. we installed at the pre-treatment stage to remove plastics , stones etc
~Ricardo C, Process Engineer, Riyadh, Saudi Arabia
Effluent Treatment (to reduce turbidity); Screening for water cleaning (wood fibre separation from); Palm Oil clarification.
~Engineering, Consulting, SAO JOSE DOS CAMPOS, Brazil
I designed a swirl separator tank to separate copper solids (100 microns up) from emulsion. flow rate 70 m3/h.
~Ittidate Rujiwasin, Plant Engineering Manager, Bangkok, Thailand
Secondary clarification for WWTP, Water Treatment Facility.
~Technical Support/Services, Barre, VT
Settling sludge, fine sediments, algae from HRP
~John N, Research & Development, Hamilton, New Zealand
Suspended matter removal from wastewater.
~Process Engineer, Rivière-du-Loup, Canada
Paper mill water clarifier.
~Arnaldo R, Production Engineer, Lima, Peru
Grinded Plastics Grains
~Joseph G, Engineering Consultant, Tel Aviv, Israel
Waste water treatment.
~Other, Montague, MA
Water treatment plant
~Engineering, Process/Production, Davenport, IA
Wastewater Treatment.
~Jay C, Marketing/Sales, Walkerton, Canada
Raw water clarifying
~Marketing/Sales, Sao Paulo, Brazil
Waste water plants
~Marketing/Sales, Mexicali, Mexico
Please share with us any “non-standard” applications that clarifiers and screens have been used for.
4 answers
I add one swirl separator tank before the existing hydro cyclone. It can separate coarse copper solids from emulsion and this reduced work load of hydro cyclone.
~Ittidate Rujiwasin, Plant Engineering Manager, Bangkok, Thailand
Small systems applications e.g. decentralized wastewater treatment systems.
~Process Engineer, Rivière-du-Loup, Canada
Combination upflow blanket settler combined with surface plate settler.
~John N, Research & Development, Hamilton, New Zealand
We also use screening in industrial and institutional applications.
~Jay C, Marketing/Sales, Walkerton, Canada
Do you know of any disastrous mistakes that occurred due to the incorrect usage of clarifiers and screens?
0 answers
FeaturesTop
What would your design or feature "wish list" be for this product?
6 answers
Applications for the separation of petroleum and derivatives from water by whatever means.
~Engineering, Consulting, Caracas, Venezuela
Remote access for monitoring status and resetting faults via the web or smart phone.
~Jay C, Marketing/Sales, Walkerton, Canada
Able to settle neutral density particles, such as the PARC hydrodynamic separator.
~John N, Research & Development, Hamilton, New Zealand
Radio control self cleaning optimising plate clarifiers.
~Process Engineer, Rivière-du-Loup, Canada
1. for clarifier - a mechanism to remove floating sludge and scum
2. for screens - stronger fine screens
~Ricardo C, Process Engineer, Riyadh, Saudi Arabia
Ppm
~Arnaldo R, Production Engineer, Lima, Peru
Is there any advice you want to share with users to help them avoid common errors in selection or usage of clarifiers and screens?
4 answers
1. clarifier - strict implementaion of PM schedule and procedures
2. screens - same as clarifiers
~Ricardo C, Process Engineer, Riyadh, Saudi Arabia
Should design over capacity because it's hard to extend in the future.
~Ittidate Rujiwasin, Plant Engineering Manager, Bangkok, Thailand
Have to be custom well designed.
~Process Engineer, Rivière-du-Loup, Canada
Soluble materials
~Arnaldo R, Production Engineer, Lima, Peru
Buying AdviceTop
Do you have any advice for people relative to buying or using clarifiers and screens?
4 answers
1. for clarifier - sludge blanket meter should be made interlocked with the RAS and WAS pumps.
2. screens - make sure that all screened materials do not drop back when moving forward.
~Ricardo C, Process Engineer, Riyadh, Saudi Arabia
Material of tank is important in long term.
~Ittidate Rujiwasin, Plant Engineering Manager, Bangkok, Thailand
Do your home work! What worked 15 or 20 years ago when the equipment was originally installed may not be the best fit for today!
~Jay C, Marketing/Sales, Walkerton, Canada
Use incline plate clarifiers.
~Process Engineer, Rivière-du-Loup, Canada
