Closed Loop Filtration
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The following are several reasons to purchase an Ebbco Closed Loop Conditioning System:
No drain in facility or cannot overflow to machine tool drain: these
customers have no choice but to go with a closed loop system.
Water and sewage costs are very expensive: Most areas this is not an issue, with water and sewage cost under 1¢ per gallon
or less. However, some areas we’ve seen are paying between 6¢ and 8¢ per gallon. If that is the case, a closed loop system
will pay for itself because the consumables used will be less than the water/sewage cost. (Remember in most cases the costs
on consumables for the closed loop system will exceed the water and sewage costs. This is obviously not the main
selling feature for the closed loop system).
3. Well and septic system water quality: Typically well water is very hard with hardness and TDS between 300 and 800 PPM. This
water must be treated before it goes to the high-pressure pump. These are normally treated with reverse osmosis systems.
(Remember water softeners only reduce hardness, they do nothing for TDS). Whereas reverse osmosis systems will treat both.
However, most R.O. systems require twice the water to generate the amount needed. In other words, if your waterjet machine needs
1 gallon per minute run, then your R.O. system may need 2 gpm to produce the 1 gpm needed for your machine. This amount of water
may overwhelm your septic field, especially when water is needed to cool the hydraulics on an intensifier pump.
NOTE: A waterjet using 1 gpm running 50 hours per week for 50 weeks per year will use 150,000 gallons of water. Using an
R.O. system the yearly total will be 300,000 gallons of water.
4. Make up water treatment such as softeners, reverse osmosis, or DI water systems:
NOTE: All waterjet pump manufacturers have strict water requirements for hardness and TDS. These range from 0 – 20 for hardness (calcium and magnesium), and from 5 to 70 PPM for TDS. The only way to achieve these numbers is with a reverse osmosis, DI water,or closed loop system.
Water softeners remove hardness, yet do nothing to reduce TDS. It is very common that waterjet users that are on city water do not treat their make up water or just run it through a water softener. Even in "good" city water the TDS is between 90 – 200 PPM. True this water is a lot better then "hard" water, but these customers typically see 400 - 600 hours of seal life, acceptable, but it could be a lot better.
Reverse osmosis systems give the proper quality water (3-5 PPM of TDS), but are very inefficient systems. A water softener is required to pre-filer R.O. systems in these applications. The downside of a R.O. system is the amount of water needed to produce the quality of water and flow rate. We have seen customers spend $5 - $10k on R.O. systems only to get astronomical water bills or find out they can't discharge into the drain.
Deionized make-up water to feed a high-pressure pump is a cost-effective way to treat make-up water when used correctly. VERY IMPORTANT NOTE: Deionizing make-up water must be done with twin-bed resin. (Separate cation and anion resin beds). Twin-bed resin gives approximately 3 PPM of TDS quality water, very close to that of an R.O. system. Warning: do not treat make- up water for high-pressure pumps with mixed-bed resin, (cation and anion resin mixed together). Mixed bed resin will give .5 or less PPM of TDS quality water. This water is very aggressive and will attack pumps/seals. NOTE: R.O. systems tend to have a higher initial cost yet are cheaper to run, whereas twin-bed DI systems are less expensive to buy but have higher operating costs.
Ebbco’s Closed Loop Conditioning System uses very little water due to the fact that they reuse the overflow water from the waterjet table. However, from evaporation alone some make up water is needed Make up water enters the dirty side of the closed loop system and the TDS is controlled before it ever gets pumped back to the high-pressure pump. NOTE: It is suggested that if a company has R.O. or DI water already in the facility, that it be used for make up water in the closed loop system, simply to reduce maintenance on the closed loop system.
5. There are five main reasons why a closed loop system should be considered for your abrasive waterjet systems.
-Eliminate the drain completely! No dissolved solids go to drain. All overflow water is filtered and reused.
-Reduce water consumption drastically – usually only 2% - 10% of normal usage.
-Drastically reduce the requirement for make up water treatment such as softeners, reverse osmosis, or DI water systems. The small amount of make up water needed is treated before it goes to the high-pressure pump.
-Maximize orifice life, reducing machine maintenance, maximizing machine performance.
-Protect your high-pressure pump! The Ebbco closed loop system always supplies the pump manufacturers specified water conditioning water quality to the high-pressure pump. The results are reduced pump maintenance and machine tool downtime.
EBBCO'S CLOSED LOOP – HOW IT WORKS
The waterjet table overflows into the dirty side of the Ebbco closed loop system. This dirty water is pumped through a series of filters, filtering the water down to .35 micron (nominal). This water is sent through a chiller removing the heat incurred from the machining process. The water then passes through a filter, which controls the TDS, then into the clean tank. The clean tank overflows into the dirty tank constantly recirculating and filtering the water. A delivery pump is mounted in the clean tank to deliver the water to the high-pressure pump. The Ebbco closed loop system addresses the four main issues concerning water quality:
Suspended solids – garnet and metal particles are filtered through a series of filters.
Dissolved solids – metals dissolved in water from the machine process as well as make up water are controlled with our TDS filter monitory system.
Organic fouling – these systems include an ozone generator, which injects ozone (03) into the water to control bacteria growth (same used on hot tubs and pools). Biocides (such as chlorine or algaecide cannot be used because the TDS filter will remove these chemicals.
Controlling temperature – a chiller is used to maintain 70ºF temperature water which is delivered back to the high-pressure pump.
These four issues must be addressed by a closed loop system, because any one of these can be detrimental to the high-pressure pump.
The intensifier pump typically uses city water to cool the pump hydraulics. Ebbco’s closed loop system chiller can be sized to remove heat from the catch tank overflow as well as cooling the hydraulics on the intensifier pump (see figure 2). Ebbco Inc. does other waterjet filtration such as garnet removal systems, overflow to drain systems, and various chiller packages. See figure (3). Ebbco can also design and engineer central closed loop systems for shops with multiple machines.
REASONS FOR BUYING CLOSED LOOP SYSTEMS
-No drain in facility
-Drain not accessible
-High water/ sewage costs
-Poor make-up water quality (Above 200 PPM)
-Well and septic water system
-Over flow water to waste treatment (Chemical treatment or evaporator)
-Cutting hazardous material (cannot discharge into local water supply)
-Potential water rationing geographic area
-Short seal life on high pressure pump .-Short orifice/ mixing tube life
-ISO 14000 (Company standard for environmental management)
-Incoming water supply not sufficient
