Slant Plate or Dissolved Air Flotation (DAF) Clarifier?
While a Slant Plate Clarifier uses gravity to settle solids in a waste stream, a Dissolved Air Flotation Clarifier uses buoyancy, which also allows for the removal of oils/grease and insoluble BOD. Both have a compact design, which is the reason why they are so popular with engineers and end users.
Slant Plate Clarifiers
In Slant Plate Clarifiers, also referred to as “inclined plate clarifiers,” a series of inclined plates are used, which provides a large settling area for particles and allows for a more compact footprint.
The reduction in floor space is significant, as it allows the settling area to be as much as 10 times more than the actual floor space occupied by the clarifier. This significant reduction in required floor space is achieved by reducing separation between plates to just two inches, and stacking the settling surfaces at an angle.
The Slant Plate Clarifier effectively uses the force of gravity to separate solids from liquid. As the solids are settling along the plate surfaces, the fluid is moving upward through the plate stacks, over the weirs, and into the discharge trough. Clarified effluent is then discharged through a flanged pipe connection at the bottom of the trough. Sludge is periodically drawn from the sludge thickening and holding section at the bottom of the clarifier.
Sample ports are provided to assist with determining the sludge level, which is periodically pumped to a batch storage tank for further liquid-solid separation via a filter press for eventual disposal.
Slant Plate Clarifiers are ideally suited for metal finishing operations, chemical processing facilities, foundries, mining, steel and aluminum plants, or any application which requires a separation of suspended solids, leaving a clear effluent for discharge.
Dissolved Air Flotation (DAF) Clarifiers
Dissolved Air Flotation Clarifiers are also very effective in removing suspended solids from a waste stream, as well as fats, oils and grease, and insoluble BOD contaminants.
Instead of utilizing the force of gravity to settle debris in the waste stream, the DAF clarifier generates millions of microscopic air bubbles to float them. The air bubbles attach themselves to the contaminants, which gives them buoyancy. The buoyant mixture of particles and air bubbles float to the surface and are removed by a skimming mechanism.
Air bubble production is achieved by pressurizing a portion of the clean effluent and recycling it back to the influent to be mixed with the waste stream. As the super-saturated water enters the DAF, the pressure is removed and millions of microscopic air bubbles are produced. The bubbles become entrained in the solids, rise to the surface, and form a bed of material that is skimmed into an isolated “float” chamber.
Dissolved Air Flotation Clarifiers can be used across a wide range of industries for a variety of applications, including: automotive, chemical processing plants, food and beverage, fracking applications, mining and minerals, petrochemical, petroleum and gas, and manufacturing.
Key Takeaway: Both Slant Plate (inclined plate) and Dissolved Air Flotation Clarifiers provide low cost, yet extremely efficient solids removal from a wide range of waste and process streams.
Slant Plate Clarifiers are optimally suited for applications where solids settle via gravity. DAF Clarifiers are typically used in applications where the solids want to float but need a boost and are more effectively removed by flotation. Clarification rates as high as 97% removal are common using Dissolved Air Flotation technology.
M.W. Watermark offers a full line of both Slant Plate (SPC) and DAF Clarifiers. We have nine SPC and DAF models available, each with increasing capacities, to cover a wide range of design flow needs. Our Slant Plate Clarifier models range from 5 to 800 GPM. Our DAF models range from a treatment surface area of 30 to 500 square feet. Each of our high-quality SPC and DAF models is made in the U.S.A.
Contact us today to discuss your application. Our team of experts can help assess the best equipment option for your solids separation needs.
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About M.W. Watermark
M.W. Watermark wants to make a difference. We are passionate about the world’s water. We are innovative, focused on customer service and always try to exceed expectations. We are an environmentally conscious company with people who are energized, encouraged and inspired to make a difference in the water business, and as a result, make a positive difference to our planet by helping to keep our shared, finite water supply clean and usable for generations to come. We build amazing, custom water and wastewater treatment equipment. We also specialize in rebuilding used water treatment equipment. Together, we can make a difference.