Great White Center Flow Screen
At-A-Glance
Type
High capacity, continuous band fine screen with low headloss and zero carryover
Screenings Capture Ratio
Highest SCR of 45 screens independently evaluated
- 93.25% with 2mm grid
- 84% with 6mm grid
Models
- Center Flow
(center entrance/side exit) - Dual Flow
(side entrance/rear exit)
Grid Opening Range
0.5mm to 25mm
Flow Capacity
0.1mgd (5 L/s) to 125+mgd (5,500+ L/s)
Grid Types
- Stainless steel laced link
- Stainless steel wire mesh
- Stainless steel perforated panel
- UHMWPE perforated panel
Stainless Steel
- T304
- T316
- Super Duplex
- High nickel stainless steels
Overview
The Great White Shark is an apex predator and rules almost every body of water around the world. Like the shark from which it bears its name, our Great White screen is designed and manufactured at the pinnacle of quality and dominates the competition.
Our Great White screens have been independently certified to have the highest screening capture ratio of all band screens on the market. Dual spray wash, patented grid design, proprietary sealing system and UHMWPE Guide Links make this an exceptional product for the filtering and offloading of water and wastewater screenings.
Very low headlosses and extremely strong, reinforced grids make these center and dual flow screens suitable for a number of applications. The patented sealing system ensures all tolerances are held to 0.5mm – even those that other screens leave vulnerable. The Great White Center Flow Screen is designed to handle low-to-high flows with 0.5-25mm openings and can be incorporated into our Septage Receiving Station.
- High screening capture for unsurpassed protection of downstream processes
- Numerous proprietary design features easily collect and offload screenings, including rags and stringy material
- Center Flow (center entrance/side exit) and Dual Flow (side entrance/rear exit) options
Features & Benefits
Rollover each feature to interact.
Highest evaluated Screening Capture Ratio (SCR)
Proprietary grid-to-frame and panel-to-panel sealing system
Uninterrupted seal between grid and frame held to <0.5mm tolerance
Reinforced center support track and structural supports
Elongated drum design
Patented grid design with interchangeable opening types
UHMWPE Guide Links
No submerged sprockets, bushings or bearings
All maintenance above channel
Dual spray wash unloading
Proprietary Bypass Gate
All T304, T316 or Super Duplex stainless steel construction
Available in Center Flow and Dual Flow models
Access panels
Fully enclosed above channel
Low power direct drive
Integrated screening handling
Single-piece or sectional frame construction
Highest SCR for 6mm (84%) and 2mm (93.25%)* means the best protection on the market for sensitive downstream processes.
*National Screen Evaluation Facility Inlet Screen Evaluation Comparative Report by UK Water Industry Research including 45 different screens by leading manufacturers.
*National Screen Evaluation Facility Inlet Screen Evaluation Comparative Report by UK Water Industry Research including 45 different screens by leading manufacturers.
Total capture of solids with zero screen bypass or carry-over with no hinges to wear or neoprene to replace. Proprietary sealing system also eliminates ragging commonly associated with other screen designs.
Tight tolerance seals provide excellent membrane or sensitive process protection, eliminate screening bypass, contribute to high screening capture and prolong the life of the equipment by eliminating grit intrusion.
Fine screens blind quickly, requiring the ability to withstand high differential head. Custom designs have been engineered to operate in excess of 33’ (10m) of differential head.
Allows channel design to handle high and low flows without grit settling. It also can provide a high capture replacement screen into existing channels with no modifications.
Perforated panel, woven mesh or laced link panels with grid openings as low as 0.5mm maintain tolerances for life and easily capture rags and wipes. All grid components are removable and can be easily accessed, repaired or replaced above the top of the channel. Proprietary grid design supports panels every 3” (75mm) for high differential, impact resistance and allows operators to change opening size in-situ without modifying equipment.
Proprietary high density, low friction drive chain efficiently directs grid around screen with no maintenance, even in abrasive and high grit applications.
No submerged sprockets and bearings below the waterline eliminates ragging commonly associated with other screen designs and the need for required maintenance in the channel. If after years of operation wear tracks need replacement they can be bolted on in the field.
Easy access to all routine maintenance and grid points means never having to isolate or dewater channels for confined space entry.
Offloads and easily removes screened material, including wipes, rags, fats and grease.
Manually or automatically operated Bypass Gate can be lifted to bypass flow through the screen, eliminating the need for additional channel or removal of the screen.
High quality, corrosion resistant materials are standard for use in the harshest environments. All materials are stainless steel, including fabricated drive components, and all hardware is coated with anti-seize to aid in maintenance.
Similar design components allow versatility for various water and wastewater applications with center entrance/side exit and side entrance/rear exit models available.
Access panels are easy to remove and completely sealed. All routine maintenance is above channel which allows for easy inspection and maintenance without special tools or access platforms.
Significantly improves safety, odor control and aesthetics for indoor and outdoor operation.
Provides reliable and efficient operation under all conditions with stainless steel, inverter duty, explosion-proof and hydraulic drive options that do not directly contact screening surface. Fractional hp and kW drives are standard on even the largest screens.
Sluices, internal compactors and sophisticated screening washing options provide a turn-key screening package.
Allows for easy installation regardless of available overhead clearance.
Applications
Very low headlosses and extremely strong, well-reinforced grids make these center flow (center entrance, side exit) and dual flow (side entrance, rear exit) screens suitable for a number of applications.
Municipal Wastewater
- Comminutor and grinder replacement
- Final Effluent Polishing
- Membrane and Membrane Bioreactor (MBR) Protection
- Package Plant Primary Treatment
- Pump and Lift Stations
- Sludge and Septage Receiving
- Sludge Screening and Thickening
- Treatment Plant Headworks and Intake
Municipal Water
- Algae Removal
- Desalination Plant/RO Protection
- Membrane and Membrane Bioreactor (MBR) Protection
- Raw Water Intake
Industrial Wastewater
- Chemical Processing
- Food & Beverage
- Manufacturing
- Meat and Poultry Processing
- Membrane and Membrane Bioreactor (MBR) Protection
- Mining
- Petroleum
- Pulp and Paper
- Textile Mills
Industrial Process
- Cooling Tower Scale Removal
- Cooling Water Intake – Power Generation
- Fish Farming
- Irrigation System Protection
- Membrane Bioreactor Protection
- Petroleum Refinery
- Raw Water Intake – Potable Water
- Uranium Refinery
Screen Grid Options
We offer opening options that include stainless steel links, wire mesh and perforated panels as well as UHMWPE perforated panels. Our Great White screens can accommodate flows from 0.1mgd (5 L/s) to 125+mgd (5,500+ L/s) and opening sizes 0.5mm to 25mm.
Laced Links
Stainless Steel Laced Links
Rectangular Openings from 1-25mm
The Laced Link-style grid is ideally suited for water and wastewater applications where fine screening is required with low headlosses.
Advantages
- Able to withstand extremely harsh environments
- Strongest grid available
- Excellent unloading of screenings
- Highest open area percentage/very efficient
- Easily handles large flows
- Extremely high open area percentages resulting in lower grid velocities
- Smaller footprint
- Wide range of opening sizes
- Versatile and proven
- Excellent in the screening of FOG and stringy material
Applications
- Municipal water and wastewater
- Combined storm overflow
- Pump and lift systems
- Sludge and septage receiving
- Food processing
Limitations
- Less efficient capture of hair and fibrous material
- Lower screening capture ratio
Wire Mesh
Stainless Steel Woven Wire Mesh
Square Openings from 0.5-25mm
The mesh-style grid is ideally suited for water applications where fine screening is required.
Advantages
- High screening capture ratio
- Excellent for sensitive process protection in water applications
- Patented grid design maintains strength and openings tolerances for life
- High open area percentage resulting in lower grid velocity
- High solids removal in water applications
Applications
- Water intakes
- Membrane protection (including MBR’s)
- Industrial processes
- Cooling water intake
- Algae removal
Limitations
- Greater water pressure/volume requirements
- Difficulty in unloading stringy/fibrous material
Perforated Panels
UHMWPE & Stainless Steel Perforated Panels
Round Openings from 1-9mm
Our perforated panel grid is excellent for a variety of municipal water and wastewater applications where fine screening is required to protect sensitive process equipment, such as Membrane Protection (MBRs).
Advantages
- Highest screening capture ratio
- Exceptional sensitive process and membrane protection (MBR’s) in wastewater applications
- Patented grid design maintains strength and openings tolerances for life
- Effectively removes hairs/fibrous material
Applications
- Municipal water and wastewater
- Membrane protection (including MBR’s)
- Pulp and paper plants
- Food processing
Limitations
- Greater water pressure/volume requirements
- Significant collection of fecal matter in municipal wastewater
- Higher headlosses
Theory of Operation
Flow passes into the screen and is diverted through the grid on each side of the unit. The Center Flow design directs water into the screen and exits out the sides while the Dual Flow design directs water from outside of the equipment through the sides for a rear exit.
Solids larger than the openings in the screen’s grid are collected and begin to form a mat which is removed undisturbed from the flow resulting in extremely high solids capture. Screening capture ratios increase as the solids form a thicker mat. Level sensing devices can be connected to variable speed drives to automatically compensate for high solids loading during peak flows or low flow conditions by proportionally speeding or slowing the grid travel speed. This increases the capacity of the equipment when needed and reduces wear, thereby extending the life of the equipment.
Solids are transported to the top of the screen as flow is constantly presented a clean grid surface. As screenings traverse up and over the top of the screen they are discharged into screening handling equipment. Drained wash water is discharged upstream – eliminating bypass.
Minimal friction is achieved through the use of Ultra High Molecular Weight Poly Ethylene (UHMWPE) and stainless steel wear surfaces. Machined Delrin spacers precisely separate elements, eliminating metal-on-metal wear and extending the life of the grid. Wide stainless steel tracks ensure years of trouble-free operation.
The stainless steel foot section and wear tracks prevent solids bypass. Unlike traditional screens, all solids with diameters larger than screen opening sizes cannot pass under, through or over the screen. Even in the event debris is not unloaded by spray wash, it always remains on the “dirty” side of the screen.
Center Flow
Dual Flow
Sealing
Our patented sealing system holds extremely tight tolerances between panels and grid to frame, eliminating the bypass of solids and intrusion of abrasive grit. We can ensure a tight tolerance down to 0.5mm in all locations of the screen, even those areas that other screens leave vulnerable.
The value of this design was tested by an independent national testing facility and was awarded the highest Screening Capture Ratio (SCR) of any bandscreen. Our 6mm screen received an SCR rating of 84% while our 2mm received an SCR rating of 93.25%.
Grid-to-Frame
- Guide Links create a continuous chain around edge of selected grid
- Formed stainless steel plate creates a labyrinth seal with Guide Link slot
- Fully adjustable and removable for inspection
- Continuously sealed for entire submerged grid path
Panel-to-Panel
- Slotted stainless steel hook links separated by Delrin spacers
- Links support panels every 3” (75mm)
- Panels are closely held against spacers
- No neoprene to erode or fall off
- No hinge to loosen or stretch
- Simple in-situ replacement
Drive
Patented direct drives efficiently power the screen. Stainless steel sprockets support and pull the black UHMWPE Guide Links, resulting in little-to-no friction and long wear. Most importantly, no part of the drive touches the grid. Therefore, a bent grid element will not be compounded into a disabled screen.
Electric Drive
Resilience to weather, wear, and lack of maintenance make this model an excellent choice for virtually every installation. Through sensible design and material selection this headworks screen is very efficient, utilizing a 0.5 hp (0.38 kW) electric motor. Screens will be wired to suit applications phase and voltage supplies. Chain guards are standard on all electrical models. Explosion proof motors are optional.
Hydraulic Drive
The Great White screen with hydraulic drive incorporates all the benefits of the electric drive with the added capability to be operated submerged. This is a useful option when flooding can occur and reliability is key.
Features
- Solid stainless steel sprockets and drive shaft
- Lifts and supports grid
- Minimum four lugs engaged per sprocket
- Adjusts to tension grid to extend wear life of screen
- Grid does not touch drive or unloading mechanism
- Low friction guide links
- Fractional hp and kW requirements
- Only two grease fittings per screen
- Direct drive uses no chains or sprockets
Project Profiles
Drawing on our 40+ years of experience and more than 2,000 unique installations worldwide, your equipment will be specifically engineered to best fit the needs of your application.
Screenings Discharge
Several discharge options are available depending on disposal requirements.
Spray Wash
Our highly effective spray wash is a superior method of cleaning the grid and prohibiting carry-over. Spray nozzles efficiently direct pressurized water over the width of the grid to positively remove all screenings and prevent carry-over. This method of discharge requires a relatively clean source of water to avoid clogging.
Deluge Wash
Low pressure deluge wash is a good alternative to spray headers if a source of clean water is not available. The deluge washer allows plant effluent or even screened flow to be used. This system also acts as a supply for screenings handling equipment.
Screenings Handling
An effective screenings handling system is a critical component to every water or wastewater treatment plant. Hydro-Dyne’s turn-key screenings handling solutions are manufactured at the highest level of quality and designed to accept, wash, dewater, compact and/or transport collected screenings. In wastewater applications, screening handling systems are particularly important as they are designed to return organic material to the channel and produce clean, dry and inorganic product that can be properly disposed of in either a container or bagging unit.
Screening Handling At-A-Glance
- Collect and convey screenings for disposal
- Returns organics and wash water to channel
- Screenings meet strict landfill requirements
- Compactors reduce disposal weight and volume
- Bagging units contain odor
- Agitation can be introduced for more thorough cleaning
- Integral and external models available
- Shafted and shaftless flights
Thresher Shark Washing Machine
- Extremely thorough washing removes virtually all fecal material and produces “clean” and compacted screenings for disposal
- High capture of inorganic solids reduces plant operating costs and improves sludge quality
- Organic material returned to plant for biologic treatment
Thank you for your interest in our company.
Do you have any questions or would you like more information? We’d be happy to hear from you.
