CASE STUDY: Location: Industry: Pollution Prevention Application: Annual Savings: Contact:

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1 CASE STUDY: Location: Industry: Pollution Prevention Application: Annual Savings: Contact: Maple Springs Laundry Hickory, NC (Catawba County) Launderer Equipment Modification and WatedChemical Conservation $103,000 Mr. Bob Daltry, Manager Maple Springs Laundry, Inc. P.O. Box 1753, Hickory NC Ph: (704) ; Fax: (704) Background: Maple Springs Laundry processes up to 40,000 pounds of hospital linen per day for a 9 hour shift. Maple Springs upgraded their washers to a much more efficient system in order to maintain compliance with wastewater discharge limits, allowing for a signficant decrease in chemical usage and water consumption. Waste Reduction Activities Process Improvement: Maple Springs Laundry decided to upgrade their existing Milner 450 rapid load washing machines with an Ultra Tandem 65W12 continuous batch washer supplied by Boewe Passat. The new unit was chosen over the existing washers because of its efficiency; it is able to wash 145 lbs of linen every 90 seconds, compared with 360 lbs every 45 minutes with the old system. It is also fully automated, reducing the time and error associated with manually intensive processes. The new machine will also allow Maple Springs Laundry to process not only hospital linen but furniture cloth, socks, and hoisery, among other things. Water Conservaton: The UT 65W12 uses a counter current wash technology that recycles the water from the end of the cycle back to the beginning. The new hydraulic press also improves drying times by 50% over the extractors currently being used. Chemical Recycle: The counterflow reuse of washwater allows for the recycle of several of the chemicals used for bleaching and anti-fungal control in the washing process. There is also an overall reduction in the amount of detergents, softeners, and alkali used in the process. Maple Springs expects that this will reduce the amount of oil, grease, nitrogen, ammonia, copper, cyanide and zinc released into the discharge water. Wastewater Control: Maple Springs is allowing for continuous exhaustion of spent process chemicals in the bath flow and laundry products to give a more uniform concentration of discharge, instead of a periodic, concentrated wastewater discharge found in conventional systems. There is also a substantial amount of water evaporated during the process. Maple Springs has installed a flume to measure the amount of wastewater discharged into the sewer to calculate sewer fees, instead of relying on incoming amounts. Waste Reduction: Maple Springs estimates that the water savings from these process improvements will be over 26 million gallons per year, amounting to over a 75 % reduction in water used per pound of laundry. It also estimates that the savings in the amount of chemicals used during the washing process is about 39% Annual Savings: Since Maple Springs Laundry processes approximately 9.5 million pounds of linen each year, the improvements in chemical loading and use reduced chemical costs from $1.06/1001bs to $0.65/1001bs, resulting in over $38,000 in chemical savings. The savings in water use and sewer fees together will be $65,000 per annum. Maple Springs will also benefit by the ability to process other types of laundry. It is estimated that the project will have a payback time of six years and nine months.

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3 Company Background li Maple Springs Laundry has been in business for over 22 years and moved from downtown Hickory to L,ongview in Maples Springs Laundry processes hospital linen. We presently scrvice 17 hospitals in North Carolina. We process an average of 2G,000 to 28,000 pounds of linen each day, six days a week.

4 Introduction To Project Maple Springs Laundry has been researching CBW, tunnel washers for approximately 5 to 7 years. We have been processing the hospital linen with Milnor 450's washer extractors, rapid load for many years. After conducting our research, we decided on the UT65W12. As you will see later in this report, the many advrtntagca of the UT65 versus the Milnor 4s01s. This project would be a major undertaking for a company the size of Maple Springs Laundry. Some of the prep work that had to be completed, included cutting trenches and drain lines, piping in water and air lines. We hail to remove a portion of concrete wall and install channel frames. We cut in drain ditches to install all drain pips. Electrical panels had to be moved and panels added for the UT65 When the equipment arrived, rigging machinery and cranes had to be used to transfer the equipmcnt to the building.

5 Economic Assessment Of Project Cast And Payback Peroid In order to get a true picture of our project cost, we took each item installed that made up the project, which is as follows: CBW (continuous batch washer) UT6SW12 Press (this squeezes out the water after linen is washed) Cake break (this is a drycr that brcaks up the linen from Press) Three loading conveyors Two dryers Two dozen slings (these are to put linen into after it is separated) Installation of all equipment: labor, pipe, valves, electrical & etc. Our immetliatc payback, less water, steam (gas), chemicals & labor. Watcr was cut from three gallons per pound of linen to 1.25 gallons. Less water, means less steam (gas) to heat the water. Our chemical cost was cut for ninetyeight cents per hundrcd pounds of linen to seventy-two (.72) cents per hundred. The UT65 will allow us to wash and bleach kmiture cloth, socks, and anything else, that needs a fast turn around. It produces one hundred fourty-five (145) pounds even ninety seconds. In ordcr to arrive at a payback period, we have to assume that Maple Springs will process nine million five hundred thousand pauntls of linen a year. We will save eleven milliorr eight hundred seventyfive gallons a year. Our dryers and ironers evaporate three million six hundred and twentyfive tliousitntl gallons, wiricli doesn't go into the sewer system, for treatment. Our complete payback based on the above will take six years and nine months.

6 ,.i Assessmcnt Of Wastewater Discharge Reduction And Chemical Loatling Reduction We based our assessments on current poundage of linen per month, which will amount to just over 9.5 million pounds per year. Our old washers were Milnor 450 rapid loads. They used three gallons of water per pound of linen. UT65 uses one (1.25) gallons per pound of linen. This is a savings of 8,875,000 gallons per year. By weighing the linen dry, then wetting it and drying it again, we will evaporate about 30% of the water. Therefore, it doesn't go into the sewer. We purchased a flume so we can meter our waste water. This tells us our total gallon of water discharged into sewer. Chemicals to wash linen was cut twenty four thousand scven hundred (24,700) pounds per year.

7 .. Discussion Of Project Advnntagea And Dinadvantagen Including Any Problems Advantages: Runs by computer, give# total weight, water and steam. Washes 145 lbs. linen ever 90 seconds. Unloads automatic on to conveyor belt. See economics assessment of project. No Disadvantages No problems encountered.

8 . *.. TECI-INICAL DESCRIPTION Water Consumption 450 Washer Extractor 3.0 gallons per pound of linen UT65 linen CBW, Tunnel Washer 0.8 to 1.2 gallons per pound of Along with reduced water consumption is also a significant reduction in chemicals. The design of the tunnel system allows more exhaustion of the chemicals in the bath flow and laundry products, rather than periodic concentrated discharges as is the case with conventional washer/extractors such as the 450's. Information: Boewe Passat Wink Davis Equipment Company

9 RECOMMENDATIONS FOR FURTHER STUDY OK TESTING ANDSUMMARY Maple Springs Laundry will continue to monitor all aspects of the UT65/12 to ensure its performance. The UT65 will sigiiificantly reduce the amount of both discharge of waste water and more importantly reduce the discharge and actual usage of chemicals.