Dissolved Air Flotation DAF System Skimmer Blades

V-Series Dissolved Air Flotation System

Ecologix V-Series Dissolved Air Flotation (DAF) systems are highly efficient at removing suspended solids and other contaminants from water. Our revolutionary V-shaped design and systems integration help remove up to 99% of TSS/FOG and 75% of BOD loadings.  Our systems are skid mounted, pre-wired, pre-plumbed, and easy to install.

ACE | Boltex-Series | ITS
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General System Overview

DAF is a highly efficient method for removal of turbidity, color, suspended solids and other contaminants from water. A recirculation loop of pressurized water is saturated with dissolved air using a multistage impeller pump. The product of this process is termed “whitewater.” Whitewater discharges into calculated points along the pipe flocculator. Microscopic air bubbles become entrained in the floc particles. When the floc particles leave the pipe flocculator and enter the body of the DAF, they rise to the surface and form a sludge blanket. As the sludge blanket thickens, a skimmer drive transfers sludge to the DAF sludge sump. From the sump, sludge is pumped to dewatering equipment. The treated water gravity flows from the DAF vessel to a clear well or city discharge point.

V-Series DAF System Specifications
Model Flow Rate (GPM) Dimensions Scraper Surface Area (sq.ft.) Dry Weight (lbs) Operating Weight (lbs)
V-408 60 8' x 4' x 8' 24 3708 13091
V-412 100 12' x 4' x 8' 40 5009 19079
V-714 200 14' x 7' x 9'6" 84 15312 48505
V-720 300 20' x 7' x 9'6" 126 20670 68091
V-725 400 25' x 7' x 9'6" 161 22163 81444
V-730 500 30' x 7' x 9'6" 196 24631 95763
V-736 600 36' x 7' x 9'6" 238 27601 111184
V-1022 500 22' x 10' x 11' 200 18312 103096
V-1030 700 30' x 10' x 11' 280 24876 140485
V-1035 800 35' x 10' x 11' 330 28304 163187
V-1045 1000 45' x 10' x 11' 430 38688 212111
V-1050 1200 55' x 10' x 11' 480 41722 234409

Flocculation Mixing Tubes


The flocculator is designed to thoroughly mix raw influent with water treatment polymers and dissolved air. It consists of a spiraled mixing tube with strategically placed polymer injection ports, highly aerated/pressurized water, and sample ports. A metered control valve manifold ensures accurate flow of pressurized, highly aerated water into the mixing pipe flocculator to enhance coalescing of microscopic air bubbles and wastewater mixing. Polymer injection ports are quick-connected, allowing easy removal and re-insertion during system operation. The Dissolved Air Flotation process utilizes design principles unique to our DAF system. The design allows for highly effective flocculator units to be installed in a footprint significantly smaller than that of other systems. Plant wastewater enters the DAF system via an ascending pipe flocculator which acts as both a flash mixer (lower section) and a gentle mixer (upper section) for superior flocculation.

Pressurized Water Recirculation


Clean, treated water removed from the wastewater discharge cell is pressurized and fed back into the system via inlet ports on the flocculator. Additionally, pressurized water is injected into the flotation cell. The Pressurized Recirculation Loop Creates Whitewater, which is a key factor to water treatment success. The Pressurization Pump is sized to provide adequate recirculation water flow at 400’ TDH. The pump is installed on the DAF flotation cell skid. The Air Dissolving Tank provides the retention time necessary to allow injected air to dissolve, creating “whitewater”. The tank is supplied complete with internal piping, inlet/outlet flanges, pressure gauge, pressure bleed-off valve, and air control assembly (solenoid valve, filter/ regulator/gauge, rotometer, and check valve). The pumps we use are side-channel multi-stage pumps, which is a unique product with characteristics of both displacement pumps and centrifugal pumps. At low flow and high pressures, our self-priming pumps have a noticeable advantage over centrifugal pumps. It allows trouble free handling of Maximum gas contents of 50% and attains pump heads which are many times greater per stage than that generated by radial flow centrifugal pumps. These pumps are essentially immune to cavitation at variable vapor pressure and therefore flow is not interrupted during partial degassing. The pressure rate is up to 10 times higher than that generated by normal pump impellers rotating at the same speed. The best part is that we can generate more air with extremely small bubble sizes of 20 microns and smaller that remain in solution for over 30 minutes, resulting in extremely efficient separation of solids from the water and very dry sludge.

Dual Chamber Chemical Reaction Tank


The Reaction tank is designed specifically as an option to allow for longer chemical contact time. The tank allows for 5 minutes of chemical reaction time per chamber. The Dual Chamber Reaction Tank features plate mounted agitators and typically utilizes a Walchem dual probe pH controller to aid in automated chemical dosage and operator monitoring. The unit can also be outfitted with a stainless steel chemical metering pump stand for application of sulfuric acid, acidic coagulants or caustic soda. This feature allows for short distance pipe runs of hazardous chemicals and minimizes operator exposure.

Flotation Cell


The flotation cell is a rectangular vessel designed to provide controlled influent wastewater velocity and optimized surface area. It contains an inlet diffusion pipe, sludge rake, and one or more blow-down valves. The blow-down valve permits removal of the small portion of sludge that settles in the flotation cell.

Sludge Skimmer


The sludge rake assembly consists of a stainless steel chain and a three-blade scraper arrangement. The sludge scrapers skim the surface of the sludge in the flotation cell and transfer the floating solids to the sludge sump. From the sludge sump a pump removes the sludge to the Thickening/Sludge Dewatering Tank.

Sludge Sump


Thickened sludge skimmed from the DAF discharges into a sludge sump. The sump has a hopper bottom with inclined sides to allow sludge to gravity feed to the suction side of the sludge transfer pump.

Discharge Cell


The discharge cell is designed to allow clean, treated water to flow downward and away from rising sludge, and then upward through a clear-well section. It contains a wastewater baffle, adjustable weir, pressurized water diffusion pipe, and blow-down valve. Clean, treated effluent, flows down and under the flotation cell, upward through a clear-well and then over an adjustable weir into a collection launder. The weir is made to be adjustable with threaded bolts. A portion of the clean, treated water, is removed from this cell via a recirculation water header piped to the suction inlet of the pressurized water recirculation pump. A portion of the pressurized water is piped into the inclined section of the flotation cell. A blow-down valve permits removal of the small portion of sludge that settles in the discharge cell. As a result of these extra clarification steps our clean water is commonly as much as 5-6 times purer than other competitive DAF systems.

Clear Well and Dewatering


Some systems employ a clear well for finished clean water inspection, post pH adjustment, or as a short term holding reservoir when the water needs to be transferred to another location for discharge or reuse. The clear well is constructed as a low side wall stainless steel tank for easy visual reference of effluent quality.

Mechanical Construction


The DAF vessel is constructed of 304L Stainless Steel with suitable stiffeners to prevent deformation under all normal stresses incurred during erection and operation. The unit can also be skid-mounted for mobility. All joints are double welded and leak tested prior to shipment. A DAF-mounted catwalk and ladder are provided for operator access to the top of the DAF vessel on large units. Handrails are painted yellow per OSHA regulations. The DAF mixing-pipe flocculator is fabricated out of 304L Stainless Steel (316SS is optional). The flocculator is mounted on legs, and connects to the main DAF unit via a 150lb flange. The flocculator and DAF system are pressure tested prior to shipment.

Automatic Control Systems


The control panel for each system can be designed to include as much or as little automation as desired by the operator and project engineers. They are designed to provide fully automatic operation utilizing a PLC (Programmable Logic Controller). User interface with the control system is provided in the form of panel-mounted selector switches, Allen-Bradley AC variable drive terminals, a pH controller, alarm with lights/horn and a panel-mounted process display terminal. Process variables and chemical dosage set points are monitored and changed via the panel-mounted display terminal. Chemical pump rates follow process flow which is monitored and controlled by a magmeter and proportional valve. Polymer usage is automatically displayed in ml/min and lbs/day on the panel-mounted display. System kilowatt-hour usage is also monitored and displayed. A fail-safe operation mode is provided that will allow the system to be operated manually in the event of a computer malfunction. A semi-automatic mode is also designed into the Ecologix control system to provide maintenance and operational flexibility.

Sludge Holding/ Dewatering


The sludge that has been removed from the wastewater by the scraper is pumped into a sludge holding tank for further thickening. From there it is pumped into a dewatering system such as Filter Press or Belt Press for final dewatering. The end result is a 25%-50% dry sludge by weight that is solid to the touch and can be safely disposed of to a land fill.


Most common industries served by Ecologix DAF Systems

Food Processing:
  • Dairy Plants
  • Meat Processing/Packing (Beef, Pork, Poultry)
  • Frozen Food
  • All Other Food Processing Plants
Heavy Industry:
  • Automotive Paint Lines
  • Bio-Fuel Wastewater Treatment
  • Metal Finishing
  • Oil Drilling/Produced Water
  • Tanker Deballasting
  • PetroChemical Processing
Other:
  • Ground Water Remediation
  • Commercial Laundry/Linen Supply
  • Ink & Dye Removal
  • Landfill Leachate Wastewater

METALS REMOVAL

Removes all common metals to less than 1ppm and into the parts per billion (ppb) level count in a continuous flow process at flow rates up to and over 1,000 GPM. Oils, grease and other contaminants are removed in the same step. Because the CRM operates in a continuous process, you can run the rest of your plant without worrying about overloading the waste treatment system.

POULTRY PROCESSING

The V series DAF system for the Poultry Processing Industry treats every type of waste stream created by eviscerating, further processing and cleaning. The system operates in a continuous process using minimal amounts of chemistry in a self-contained, skid-mounted unit that uses little floor space and requires minimal operator intervention. The powerful microscopic bubbles float solids to the surface as shown to the right.

The Application
Ecologix supplies wastewater treatment systems to both poultry kill plants and further processing plants. Poultry processing creates different types of waste streams depending on the type of plant and its products.

Kill Plants
Plants that process chickens or turkeys and ice pack whole birds for shipping typically run two shifts which produce two distinct types of waste.
(System Design - Typical for Poultry Processing)

First Shift (slaughter)
Dirt, grit from craws feathers, blood and feces from the eviscerating lines make up the waste stream. Turkey plants produce heavier loadings of dirt and grit.

Second Shift (cleaning)
This is the more difficult of the two streams being made up of blood and dirt combined with high pH cleaners. The timing of the waste flows is difficult as well. Chillers and scolders are usually dumped within an hour of one another. Systems must be sized to accommodate the surges especially in plants with contracted cleaning services where the contractor is under time restrictions and pushes the waste treatment system to its limit.

Further Processing
Whether combined with kill operations or a separate plant, further processing introduces a wide range of contaminants beyond those found in the birds themselves. Cooking produces large volumes of fat, oils and greases from the birds and from frying operations. Ingredients such as breading, seasoning, marinade, flour, starch and sugar complicate the waste treatment process. Flour and sugar, for example, quickly become dissolved making it extremely difficult to remove. Cleaning introduces high pH cleaners from boil-out steps and other cleaning operations.

The Challenge
The challenge is to design a waste treatment system that can handle the wide fluctuations in waste streams from shift to shift. Designing a good system requires an in-depth knowledge of the poultry industry and a specific understanding of each customer's operations. The system must be sized to accommodate the volume and timing of various flows. It must also easily adapt to changing waste conditions without putting unreasonable demands on the operators. Finally, a waste treatment system must be cost effective. It cannot use up vast tracts of valuable floor space nor can it use large quantities of chemicals. It must absolutely keep the customer in compliance with the POTW's discharge limits.

INDUSTRIAL LAUNDRY and TEXTILE RENTAL

Our DAF systems apply to both Industrial Laundry operations and Textile Rental companies operating their own washing plants.

The Application
Textile Rental Companies and Industrial Laundry Operations wash a wide variety of products from napkins and table linens to shop rags and floor mats. These different wash products produce different types of waste streams that can vary from batch to batch.

Challenges
Discharge limits imposed on laundries are becoming ever more stringent. Lower limits are forcing plant managers to upgrade existing waste treatment systems or install new systems where none were needed in the past.

Depending on the product mix in the washroom, the time of day, the season or other factors, the nature of the waste stream sent to the waste treatment system can fluctuate widely. Traditional waste treatment methods rely on large equalization tanks and long dwell times to archive proper treatment conditions. These systems use large quantities of chemicals and take up vast amounts of valuable floor space. On top of the waste treatment challenges, water supplies are dwindling and the cost of clean incoming plant water is becoming significant.


Features

  • Welded frame
  • 304 stainless steel tank
  • White water pump
  • Adjustable weir
  • Integrated PLC controls
  • Sludge skimmers

Benefits

  • TSS/FOG reduction up to 99%
  • BOD reduction up to 75%
  • Compressed air not required
  • Low maintenance
  • Self contained treatment unit

Options

  • Sludge auger
  • Staircase and mezzanine
  • Other materials of construction
  • Chemical mixing/flocculation tubes
  • Dual pumps
  • ACE Technology integration
Dissolved Air Flotation Process DAF

V Series Dissolved Air Flotation DAF