Low-Head Filters High-Efficiency Polishing Filtration for Water and Wastewater Treatment

Transcription

1 Low-Head Filters High-Efficiency Polishing Filtration for Water and Wastewater Treatment

2 Two Backwash Travel Systems EIMCO Traveling Bridge and Traveling Hood Filters provide continuous water and wastewater filtration with automatic, online backwashing. Specifically designed for low head filtration with shallow beds, these heavyduty filters adapt easily for use with dual media or beds of up to four feet in depth. Recent innovations in underdrain design and backwash equipment transport offer the user significant improvements in filter performance and substantial reductions in capital and operating expenses. Traveling bridge or hood -a tale of two transports EIMCO Low Head Filters are available with two transport arrangements for the backwash hood and pump: a conventional railmounted traveling bridge, and pneumatically driven self-propelled hood. Both transport systems provide elevated travel, indexing hood location and sequential media cell cleaning. But by eliminating the material and fabrication costs of the suspension bridge, the Traveling Hood Filter offers a simpler, more compact installation at substantially reduced equipment costs. The EIMCO Trac-Vac hood drive Traveling Hood Filters use a proven pneumatic drive system originally developed to propel suction sludge collectors. With over 1,000 units installed nationwide since the early 1980's Trac-Vac drives have earned an enviable reputation for mechanical reliability and control flexibility. The Trac-Vac drive employs pneumatically activated sliding clamps to transport the backwash hood and pump along a guide rail. The traveling hood is equipped with a single, center-mounted traction unit, a pneumatic travel lift, and spring-loaded outboard stabilizers. Control is provided by a programmable controller through an interface of electrically Traveling Bridge Filter actuated pneumatic valves. All hood and drive components are fabricated from stainless steel and corrosion-resistant, non-metallic materials for long, trouble-free service life. EIMCO Traveling Hood Filters Eliminate traveling bridge expense Lower maintenance no gear motors, drive shafts, bearings or pillow blocks to maintain Eliminate bridge alignment problems Easier to enclose within standard height structure Can often run on available plant air Drive mechanism, hood and rails of all stainless steel construction Simple, reliable pneumatic drive for Traveling Hood Filter 2 Traveling Hood Filter

3 Efficient, Compact Basin End-drain basin design and single pump backwash shrink filter footprint, reduce construction expense All our Low-Head Filters feature an end-drain basin design in which filtered water flows through an unpartitioned plenum beneath the underdrain. Combined with a single-pump backwash system, this arrangement eliminates the construction expense of a side effluent channel, and the cost of a second outboard pump and backwash shoe sealing equipment. The resulting filter occupies a smaller footprint, is less expensive to build, simpler to maintain, and operates more efficiently than competitive two-pump backwash filters. 1. Traveling Bridge (Optional) 2. Backwash Pump 3. Backwash Hood 4. Rails (Optional) 5. Influent Ports 6. Wash Water Trough 7. Level Sensors 8. Media 9. Partition Plates 10. Media Support Panels 11. FlexKleen Nozzles 12. Partition Support Concrete Curbs 13. Effluent Plenum 14. Filtrate Flow 15. Air Header (Optional) 16. Festoon System Note: Traveling Bridge Filter is illustrated. Items 1 and 4 are for Traveling Bridge only. 3

4 Single Pump Simplicity and Efficiency Backwash cycles can be started manually, by timer, or by high level sensors. When a cycle is complete, the backwash assembly returns to its starting position, ensuring that the next cleaning cycle begins with those cells that have been in service longest. Adjustable timers allow easy variation of wash duration, for quick adaptation to upset conditions or other plant flow variations. Indexing single pump backwash system cleans media more effectively, extends filter runs Our Low Head Filters feature a media bed with permanent cell partitions and an unpartitioned effluent plenum, separated by impermeable media support panels. Filtrate and wash water pass through the media supports by way of flow control nozzles that uniformly distribute all flows. During backwash, each filter cell is sequentially isolated for individual cleaning. The backwash assembly stops over each cell and lowers the cleaning hood until a flexible seal contacts the partition plates. The backwash pump is then activated, pulling filtered water from the effluent plenum through the flow controls nozzles, fluidizing the media and vigorously scrubbing the entire bed volume and surface. Trapped solids are released into the backwash, leaving the media thoroughly cleaned and ready for another filtration cycle. Normal backwash time is about 60 seconds per cell and backwash flow rate through the cell is constant during that interval. 4 The end of media migration The indexing, single pump backwash system controls media migration in two ways. First, pump operation is intermittent. Only when the backwash hood has completely isolated a media cell is the pump activated, and pumping is stopped before the hood lifts to resume travel to the next cell. Second, cell partition plates are sized deep enough to provide ample freeboard to contain the media bed, even with 20% + expansion during backwash. The media bed is completely contained throughout the backwash cycle, eliminating any possibility of lateral media migration.

5 Features The two photos above show lab tests of backwash performance of an underdrain equipped with FlexKleen Nozzles (top) versus typical porous blocks. Note the more uniform flow distribution and vigorous bed fluidization provided by nozzles. FlexKleen Nozzles ensure uniform flow distribution All our Low-Head Filters use FlexKleen flow control nozzles to collect filtrate and distribute backwash flows. By imposing a uniform headloss across the entire filter, nozzles provide more efficient bed utilization, more thorough and equal cleaning, longer filter runs, and less backwash waste than any other porous block alternative. Optional air scour backwash For applications with heavier solids loading, effective air scour backwashing is an easily added option with our Low-Head filters. A simple air header installed in the effluent plenum is the only additional piping required. Air from this header forms a uniform blanket throughout the effluent plenum. Upward flow through the media support panels is metered and evenly distributed by the FlexKleen nozzles and tailpieces, ensuring thorough agitation of the entire media bed, freeing even deeply embedded solids into the wash water stream. Single Pump Backwash Features: Superior media cleaning, less frequent backwashing Indexing hood travel and positive hood-to-partitionplate seal eliminating lateral media migration Complete bed fluidization with approximately 20% expansion Constant Backwash flow rate Excellent restratification of dual media beds Aggressive media surface scour Cells cleaned in same order each cycle Variable backwash duration Lower operating and maintenance costs Equal media fluidization in each cell Smaller filter footprint Easy addition of air scour backwash 5

6 Fast, Easy Underdrain Installation All of our underdrain components are precision fabricated from durable, corrosion-resistant materials. Assembly is quick and easy, and requires no leveling angles, grouted flow-control ramps or header sections. Large media support panels minimize sealant application. EIMCO Underdrains feature Quick, Simple installation Durable, precision manufactured components Easy addition of air-scour backwash Fewer, shorter sealed joints All corrosion-resistant materials EIMCO Underdrains eliminate: Separate side effluent channel Second backwash pump and sliding shoe Balancing multiple backwash pump flows Leveling angles Grouted flow control ramps Porous blocks Biocidal treatment of underdrain components 6

7 Retrofits and Package Plants An ideal retrofit system Simplicity and ease of installation make our Low-Head Filters an ideal solution for retrofitting existing filters. Prefabricated components make underdrain replacement fast and economical and EIMCO Low-Head Filters fit into any basin, including those originally designed for two-pump filters, with no impact on filter hydraulics. Steel tank package plants Prefabricated steel tank filters are available fully factory assembled for fast installation and start-up. Installation consists of placing the filter foundation slab, making piping, electrical and/or pneumatic connections, charging it with media, and starting feed flow. EIMCO package plant filters offer Quick design and delivery Lowest installed (evaluated) cost Fast, easy installation Convenient increase in filtration capacity Smaller footprint than two-pump filters Low-Head Filter sizes Concrete Tanks Bed Width: 6'- 0", 9'- 0", 12'- 6", 16'- 0" Bed lengths: Up to 275 feet Steel tanks Bed Width: Up to 11 feet Bed lengths: Up to 50 feet 7

8 EIMCO Low-Head Filters In addition to providing a complete line of process equipment, Eimco Water Technologies is your source for everything necessary to meet the total needs of a project from inception to start-up and beyond. Flowsheet Capabilities Eimco engineers can help you with the design of your total flowsheet, ensuring that all your equipment will work together for optimal performance and ease of operation. Tankage and Erection We can take the stress out of coordinating an independent contractor who may not be familiar with all the details necessary to install your thickener or clarifier. Our experienced tankage and erection crews can save you money and stress by doing all your field work and turning over to you a trouble-free machine. Upgrades and Retrofits Wastewater technology is constantly advancing. Let us show you how you can incorporate state-of-the-art design improvements into your existing wastewater treatment equipment. Many upgrades can pay for themselves in a matter of months and help increase capacity as well as improve performance. Service Our staff of skilled mechanical and process engineers can keep your equipment in top condition and help you avoid costly unscheduled interruptions. Eimco Water Technologies is here to help you with all your solid/liquid separation needs. Please call us to find out more about how our technology can improve your productivity. Copyright 2006 GL&V.. ETE023 US: Canada: For more information visit us at