For more than two decades, Earthwise Environmental™ has designed and implemented water management solutions for hospitals, schools, hotels, food processing plants, light industrial, commercial and residential buildings. Earthwise Environmental clients include Northwestern Memorial Hospitals, University of Chicago Hospitals and facilities, Soldier Field and Hamilton Partners' 20 locations, among others.

Long before "green" became the new buzzword, Earthwise Environmental was working to make water safer and conserve Earth's most precious resource.

Earthwise Environmental Case Study: Hospital Central Plant

One of the largest 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. The hospital's discovery of positive Legionella counts in its cooling tower system and excessive corrosion in its chilled water system required immediate intervention.

The Earthwise Environmental™ engineering survey and inspection process found leaking chemical feed stations and insufficient biocide feeds, as well as the absence of a proper Legionella control program. Further inspection found the chilled loop system running at a corrosive pH of 5.5 with over 100+ PPM of dissolved iron. Neither a filter changing program nor any corrosion coupon studies were in place.

Earthwise created and instituted solutions to the central plant's challenges that served to reduce the hospital's liability from hazardous chemicals and potential Legionella, provide labor savings, create increased energy efficiency and provide long-term protection of equipment.

Specific Solutions:

Cooling Tower

• Custom design of new feed and control system
• Initiation of dual Legionella-specific biocide program and testing
• Computer-based 24-7 monitoring and control capability
• Weekly service visits

Chilled Loop

• Developed a custom-formulated product to raise and buffer pH to 9.0
• Instituted a "Step-down" filter approach from 25-10-5 micron in three months
• Switched to silica-based corrosion inhibitor for multi-metal protection

Favorable Outcomes:

• Reduced the hospital's liability and environmental impact from hazardous chemicals use and storage
• Proactive Legionella control has consistently led to 0 positive results, insuring the safety of the hospital employees and patients
• Installing a "real time" 24-7 online monitoring system reduced staff labor hours and allowed instant knowledge of the water conditions throughout the plant
• Insuring long-term protection of the chilled piping system eliminates need for costly capital replacement
• Reduction of labor hours for filter changes
• Cleaner heat transfer surfaces resulted in increased efficiencies and lower energy costs

Earthwise Environmental Case Study: Injection Molding Facility Clean Room

A clean room medical injection molding facility invested more than $1 million to install five new molding machines, as well as a new packaged pumping and filtration system designed to increase production speed of manufactured parts. The facility was experiencing challenges. Filters were plugging with deposits and funneling cloudy water into the system, creating corrosion issues and lost production time. The overall cost of constant filter changes by employees was calculated in excess of $200,000 annually.

The Earthwise Environmental™ engineering survey and inspection process found that while the new equipment was top-notch, the equipment upgrade did not include proper sanitation and anti-corrosion treatment of long sections of newly-installed black iron piping. The Earthwise Environmental engineering survey also found the overall system contained numerous ‘dead legs’ in piping runs as well as galvanic couples throughout the plant - factors contributing to system bacteria build-up. Other trouble spots in the review by the Earthwise team of Certified Water Technologists determined the system contained high iron and copper levels and a low pH. The survey also discovered possible cross connection/contamination between the cooling tower and the chilled water loop feeding water into the injection process.

To solve the multiple issues and reduce unnecessary production downtime, Earthwise confirmed the need for sulfate-reducing bacteria (SRB) from the tower cross-connection and implemented on-line sterilization with a bio-dispersant and SRB biocide. Existing nitrite treatment procedures in place were replaced with silica treatment. Once the system was sterilized, Earthwise developed a program to automate the feed of biocide and likewise perform routine system water biological testing.

The facility review also resulted in equipment adjustments to improve overall efficiency and water quality. New dual filters were installed for the five new machines to eliminate downtime during changes as well as labor costs. The existing 125 micron filtration system with a screen-type backwash filter was eliminated in favor of 10 micron, bag-type full-flow filter vessel. The galvanized series couples were replaced with stainless steel manifolds, and a color-coded hose system was put in place to eliminate cross-contamination of the water tower and chilled loop system.

Benefits:

• Immediate labor cost reductions through elimination of injection molding machine filter changes. Prior to implementation of Earthwise recommendations, facility employees spent an average of 20 minutes per filter change three times a week on five machines, totaling six hours of labor weekly at a cost of $750 per hour. New filtration translates to labor savings of more than $200,000 annually and a 60-day return-on-investment, plus additional production time.
• The changeover from galvanic couples to stainless steel manifolds saves labor and capital costs associated with corrosion and piping replacement.
• Long-term protection of the chilled piping system eliminates the future replacement need, a costly capital expenditure.
• Reduced energy costs through increased efficiencies at heat transfer by elimination of the bio fouling through the SRB biocide program.