One of the the largest and most well-respected teaching hospitals in Illinois is also home to a central plant with 7,000-tons of cooling tower capacity and a 100,000-gallon central chilled water loop. When new corporate responsibility guidelines were released, encouraging sustainability and green practices in facilities, the hospital turned to Earthwise for advice. The discovery of positive Legionella counts in the hospital's cooling tower system required immediate intervention. Committed to providing our clients with the safest, most environmentally beneficial technologies, we installed a MIOX® AE-4 on-site mixed oxidant disinfection system in July 2011, replacing a 12.5% bulk liquid sodium hypochlorite for the 3,000 ton cooling tower in the hospital’s neurosurgery center. Located near both a diesel generator and kitchen exhaust fan, the cooling tower was experiencing excessive biofouling from fats, oils, and greases. A common regimen required several biocides including bleach, DBNPA, and a specific algaecide, along with frequent manual brushing of the outer fill and upper distribution decks by hospital personnel. Legionella testing was routinely conducted by hospital staff and positive readings were noted on several occasions in 2010. Since MIOX was installed in July, no positive results have been noted. The operating engineer noted that the cooling tower is visibly cleaner this year and the slime and live green algae is gone from the hot distribution decks. Storage and handling of hazardous chemical bleach have been eliminated and the hospital’s biocide program is more effective and efficient.
The Martindale Water Supply Corporation is located on the San Marcos River, thirty miles south of Austin, Texas, in Martindale, population about 3,000. The Corporation utilizes ground water from two alluvial wells. The Corporation completely rebuilt their water treatment system in 2000, converting to membrane filtration. The new treatment system consists of pre-chlorination, pre-filtration, ultra filtration using a Koch HF -26 membrane cartridge skid, ending in clear well storage. In order to reduce algae formation in our treatment system and to achieve the required chlorine residual in the distribution system we use a 2000 model SAL 80 MIOX system. Martindale WSC has been using the same SAL 80 for eleven continuous years. The MIOX disinfectant solution has proven very compatible with the Koch hollow fiber filters. Our first set of filters lasted twice the expected lifetime of five years. Clean filters require less cleaning cycles, less down-time. We’ve always received excellent service from MIOX whenever parts or technical assistance are needed. The SAL 80 has been quite reliable, operating now for 25,460 hours. I’ve replaced three cells, one brine pump, and one power supply. The main reason I initially selected MIOX for our needs is safety. I have dealt with gas chlorine for many years. Our water treatment plant is located in the center of the town. Private residences are within 100 feet. Using MIOX allowed for the location of the disinfection generation system to be safely located in the same building housing our main office, laboratory/SCADA control room, and ultra-filtration skid.
I have been very pleased with the performance and reliability of the SAL 80 system. I would recommend MIOX systems for consideration whenever considering water disinfection systems.
I have been maintaining and installing treatment systems professionally for 16 years. I have been installing and using MIOX AE-4 systems for 8 years. I am currently, and have been for the last 6 years; living and working on clean water projects in Roatan, Honduras. I have three AE-4 systems treating water that serve poor colonias, small villages, my home and some beach condominiums. The environment here is very hard on equipment. The salt air, high temperature and outrageous humidity destroy computers, cars, cell phones, appliances, TVs and most everything else. The electricity delivered here is very unclean with high volt spiking, running on low voltage and blacking out frequently with surges. I have been very impressed with the performance of the MIOX system in this harsh habitat. The systems safety devises take care of the dirty power and surges. All three systems have shown no adverse corrosion and keep running perfectly with normal maintenance. I have been equally impressed with the longevity of the chlorine residual from the mixed oxidants. Because of pumping and power interruptions many of the colonia residents store water for many days in loosely covered drums. This is a treatment nightmare in a warm moist environment with many mosquitoes. However, even after 5 days there can still be trace amounts of chlorine for safe disinfection. Out of all the systems I have worked with I chose MIOX to work for us in Honduras and it has proven to be a wise choice.
Chuck Laird, (Pastor of Calvary Chapel Roatan, Owner Terra Art Water Operations, Roatan, Honduras)
Prestonsburg City Utilities Commission (PCUC) is a division of the City of Prestonsburg KY located in Eastern Kentucky approximately 120 miles east of Lexington Ky. During the year 2005 PCUC entered into an expansion/upgrade project at their Water Treatment Plant (W.T.P.). During this project an array of concerns were discussed about the several options available for the disinfection process.
The W.T.P. is located in a residential area and adjacent to a 650 student Middle School. A Nursing Home, State Resort Park, Senior Citizens complex and several hundred homes are inside a radius of one mile from the treatment plant. Safety became a huge factor in the decision making process because of the evacuation area. With safety issues being the number one concern the financial burden of HAZMAT training for all emergency respondents and transportation of the hazardous gas throughout the City would create an additional financial burden on the ratepayers throughout our service area. When on-site storage of chlorine gas was no longer an option other factors needed to be considered.
Water quality also became a concern. Over the past few years PCUC started to develop a limited number of disinfection by-product problems. During the warmer months of the year these problems had become a source of monitoring violations. This also led to an expensive task of public notifications in response to these violations.
After several meetings to discuss the available options that remained, PCUC chose the MIOX system. We utilize two (2) 500-N units and a 45 ton salt silo. We also utilize two (2) bulk storage tanks for the daily storage of the finished product. Unfortunately we’ve replaced both storage tanks due to tank failure. The MIOX representatives were very helpful during this changeover. PCUC used all in-house staff to do a self install of the complete disinfectant process units. MIOX representatives were very helpful and supportive during the installation process.
The Prestonsburg City’s Utilities Commission feel very confident in the decision made to use the MIOX system. We have created a much safer environment for not only the employees but the surrounding community. This system was also instrumental in improving water quality issues for our system.
We look forward to the opportunity to demonstrate the MIOX system and discuss any/all aspects of the entire installation or the performance of the MIOX system.
