Lamella clarifiers are designed to remove particulate matter from liquids. These systems have been used extensively for industrial, construction and environmental remediation applications. In contrast to conventional sedimentation/clarifying units, lamella clarifiers contain a series of inclined plates, which provide a large effective settling area within a considerably smaller footprint.
The influent solid/liquid stream is stilled upon entry into the lamella clarifier unit, and solid particles settle onto the plates, accumulating and thickening in collection hoppers at the bottom of the unit; the clarified liquid exits the system through an outlet weir.
They are ideal for applications where the solids loading is variable, and the solids sizing is fine. They are more common than conventional clarifiers at many industrial sites, due to their smaller footprint.
A lamella clarifier Separates settleable solids from liquids. All solids that sediment in each time, can be separated easily and economically with the lamella separator depending on the density – usually solids larger than 50 micrometers in diameter. Most lamella are custom-made to separate smaller particles and turbid substances. This gives provision for coagulation and flocculation to create settleable flocs.
To supplement homogeneity of the influent water with the chemical aids needed to coagulate and flocculate in a timely manner, the Lamella clarifier is fitted with a Zeta Potential Mixer, ZPM. This amplifies the coagulation and flocculation reactions for the conversion and precipitation of dissolved components into small particles. The cavitation reactions provide the perfect mixing and turbulent environment necessary for coagulation using polyelectrolytes – Inorganic and Organic polymers.
The ZPM neutralizes the electrical charge (Zeta Potential) on dissolved chemicals and small particles to make some positive and some negatively charged. The opposite charges attract, and this causes coagulation and flocculation. As the electrical potential drops to neutral, the redox oxidation potential of the water increases by up to 200 mv, effectively the water is beginning to disinfect itself without any chemicals. ZPM mode of Action may be illustrated as the butter processing from milk. Milk is colloidal in nature. However, by shaking the milk consistently, butter is formed. The oil particles come together by way of charge neutralization and the whey – Watery content of milk is separated.
The clarified water is then passed through a pressure sand-filter.
The water is stored in a tank for further treatment and disinfection depending on the intended final use. Sand filters become exhausted over time and require backwashing by reversing the flow.
Benefits of using a lamella clarifier.
- It is a compact design and saves space compared to sedimentation tanks.
- As a result of the slanted funnel, the sludge can easily be transported through pumps. No manual sludge handling is required.
- There is almost no maintenance.
- It is a low-energy system – Can be installed remotely and run on solar or alternative renewables.
- Can be automated with no manual handling except for remote monitoring.
- Expandable by adding additional modules with minimal concrete works.
- Extendable by different add-on parts depending on its case of application. For instance, Scraper, Floating sludge scraper, Sludge level measurement, Vacuum belt filter for sludge dewatering etc.
- Use of organic polymers as coagulants and flocculants ensures no residue is carried forward or downstream.
- Microbial disinfection is drastically reduced.
It can be extended by different add-on parts depending on its case of application such as:
- Scraper
- Floating sludge scraper
- Sludge level measurement
- Vacuum belt filter for sludge dewatering.
