Water Innovations Facility Upgrade
Water Innovations, CIX water recycling system
Water Innovations, CIX water recycling system
Posted on: 4/1/2016
FROM: Water Innovations
Water Innovations, CIX water recycling system
Water Innovations’ complete ion exchange water recycling system is an integrated skid-mounted system engineered for closed-loop recycling of metal finishing rinses. This system is designed to produce deionized (DI) water at 75 percent cost savings and provide quality water with counter-current regeneration of packed-resin beds using feed-forward grain counting, as well as feedback based on outlet water conductivity and pH. These systems are designed with a multistage feed pump, duplex carbon and bag ﬁlters, duplex cation and anion exchangers and a DI water pump.
This calculation is “fully-burdened” including ongoing operating costs and routine & long-term service requirements. While calculated for a 10 gpm CIX10S, it can be generally applied to all CIX systems. Based upon known CIX operating parameters and typical water & chemical costs, with 24-hour operation 26 days per month at 10 gpm flow with feed water @ 200-ppm TDS.
Labor: Assumed $12 per hour wage and a routine daily operating requirement of 1.5 hour – $468 per month
Electricity: Assumed 460V 3Ph power @ $0.10 per KWH to operate feed & DI Water pumps – $35 per month
Bag Filters: Assumed 2X per week change out of 20-inch 5 micron filters @ $5 each – $40 per month.
Resin Replacement: Conservatively-assumed every 4 years of 5-ft3 cation @ $100/ft3 & anion @ $250/ft3, 1 man-day labor at $150, waste disposal of 2.5 drums @ $150 each; for $2,350 total or $49 per month.
Carbon Replacement: Once per year including 3-ft3 @ $250 & ½ man-day at $75 for $255 total or $27 per month.
Regeneration chemistry: Assumed 2 cation regens per day using 9.8-gal 32% HCl @ $2/gal or $19.60/Day & 3 anion regens per day using 5.1 gal 50% NaOH @ $3/gal or $15.30/day for $39.20/day or $1,019 per month
Wastewater: Assumed 1 carbon backwash/week producing 80-gallons or a total of 320-gallons per month, 3 cation regenerations per day producing 255-gallons or a total of 6,630-gallons per month, and 3 anion regenerations per day producing 285-gallons or a total of 7,410-gallons per month with a combined water/sewer cost of $6/1,000-gallons and treatment costs of $9/1,000-gallons, for a combined cost of $215 per month.
Total Operating Cost: Total estimated operating cost as detailed per above is $1,853 per month.
DI Water Cost: At 10-gpm service 24 hours-per-day/26 days-per-month, 374,400 gallons of rinsewaters would be processed each month with 14,360 gallons lost to backwash & regeneration for a total volume of DI water produced of 359,640. $1,853/359,640=$0.00515 or $5.15 per 1,000 gallons of DI water produced.
Comparison with Alternatives: While every facility is different, the assumed combined cost for wastewater treatment and water/sewer is $15 per 1,000 gallons or nearly 3X rinsewater recycling by ion exchange so for 374,400 gallons per day, the expense for conventional treatment is $5,616 per month. The expense for DI Water from Service DI is typically $50 or more per 1,000-gallons or 10X or more than on-site regenerable ion exchange for a relative monthly expense for SDI of $18,700. Another alternative is Reverse Osmosis (RO) followed by Service DI with an operating cost somewhat less than recycling by ion exchange although “back-end” RO is problematic because of the potential for membrane fouling which greatly increases its need for membrane replacement and overall operating cost.
This calculation was performed by Steven A. Ward, Vice President of Sales for Water Innovations which engineers and markets ion exchange water recycling systems. Steven earned an MPH degree, completed his thesis examining the economics of wastewater treatment in the printed circuit board industry. For more information please contact Sales@waterinnovations.net or by telephone at 760.294.1888 to discuss how this estimate may differ from other applications.
Let me start by saying that EXAIR Corporation and Water innovations, Inc have nothing against buckets, or ladders. We use them both here for a variety of tasks, and are very satisfied with them. But when they’re used together…that’s where we’re going to take exception. And we’re not the only ones.
I had the pleasure of speaking to CJ Ward an expert technician with Water innovations, a San Diego based company that provides world class water recycling equipment & services. They use our Model 140200 2″ NPT Threaded Aluminum Line Vacs to move bentonite clay (an amazingly versatile purification & absorption media) from 50 lb bags into a hopper. It is then dispersed into a holding tank of oily water, where it removes the pollutants and impurities, allowing for clean recycling. And, since they no longer have to carry it up a ladder and pour it in, it’s also safer and more efficient.
EXAIR Corporation and Water innovations are committed to being proactive about the way we impact the environment. Our Sustainability Plan details the way we do this in regards to our responsible consumption of resources, our conscientious waste recycling measures, and the comprehensive impact of our products…everything from materials & design, to their efficient usage, to packaging. So, when our products are used in application geared toward like-minded goals, it’s a win-win-win. For EXAIR, our customers, and the environment.
This is one of many ways that EXAIR’s diverse line of compressed air products are not only making processes more efficient, but making the world a better place through dedication to being “clean and green.”
For high-quality surface finishing, you must have a top-notch critical cleaning process. It is essential to remove oils, metalworking fluids and fluids used to prevent corrosion or other surface damage during storage. In the euphoria associated with finding a cleaning agent/cleaning chemistry that actually removes the soil without damaging the metal, it is easy to forget that once that cleaning agent has done its job, you typically have to remove it. The cleaning process is only as good as the rinse step. Inadequate or inefficient rinsing can be costly.
In monitoring rinse water, one issue is what the rinse water “looks like” after use when it is ready to be removed from the process tank. Another issue is water conservation. You have to adhere to environmental regulations covering when and how water can be released from the system. If you monitor, it may be possible to reduce water added to the rinse system, which can lead to cost savings. However, the focus for manufacturing is the quality of the rinse water that comes into contact with the part being rinsed, and the goal is to understand how water quality impacts product quality and performance. Monitoring is a tool, not an end in itself. Getting the right quality rinse water in contact with the part involves starting with optimal process design, overall process control, maintenance and employee training.
Consider a small cleaning system consisting of one wash tank containing an alkaline cleaner and three rinse tanks. The cleaning process consists of someone manually submerging the parts in each tank. In such small systems, one simple approach to monitoring rinse water quality is to check the pH. Too often, we find that the cleaning solution is, say, pH 9 and the final rinse tank is also pH 9. It may be that the parts are effectively being cleaned in three wash steps and zero rinse steps. Before setting up a rinse water monitoring program, perhaps process design is needed to manage carryover into the rinse tank and to establish rinse water quality. It can be truly illuminating to measure the pH of the incoming rinse water. The pH is considered a secondary standard by the EPA, and the listed range of pH for drinking water is 6.5–8.5.
Let’s review the pH scale, which is logarithmic, much like the Richter scale for earthquake measurement. A one-point difference on the Richter scale can make the difference between a gentle wake-up call and a colossal event. A one-point difference in pH can shake up your yield, and not necessarily in a good way. Some municipal water that is considered acceptable for drinking may be unacceptable in metal cleaning and metal surface prep. If you are using untreated tap water to rinse “fussy” alloys like brass, rinse water that starts out above pH 8 could contribute to surface quality problems. These problems can be magnified by even small amounts of cleaning agent residue.
Monitoring pH. Sometimes, we are told the pH is being monitored, but there are still problems. Assuming that the wrong pH rinse water is a cause of surface quality issues, the question arises as to how pH is determined. pH paper is relatively inexpensive and rapid. However, relying on pH paper to monitor process baths, even rinse baths, can provide a false sense of security. Interpreting color is subjective; some people are better at discriminating subtle differences in color than others. Also, as a rule of thumb, the fewer things there are in a mixture, the less detective work it takes to characterize that mixture. Rinse tanks are not necessarily simple; they may contain residue of metals, salts and metalworking fluids. “Fully formulated” cleaning agents have lots of “stuff,” like organic and inorganic chemicals, in them that often interfere with the pH paper, giving misleading results. Using a pH meter is more likely to give a “true” reading of the level of alkalinity of acidity.
Monitor the right thing. When monitoring rinse water, some manufacturers automatically assume that monitoring rinse water pH is the “be-all and end-all.” But knowing the pH may not be enough. What’s important to monitor depends on what is acceptable relative to the part being cleaned. Many aspects of rinse water can be monitored. Examples include total dissolved solids, oil level, conductivity or even a specific chemical or class of chemicals. Choosing the right thing to monitor means understanding product requirements.
Barbara Kanegsberg and Ed Kanegsberg Ph.D. are industrial product cleaning consultants with BFK Solutions LLC, and industry leaders in critical/precision and industrial product cleaning. For questions or to receive their newsletter, contact them at 310-349-3614 or email@example.com.
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