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Heat Recovery, Water Reuse Offer Options to 'Plug' Drain

To get the most of the precious water and heat energy that their plants use daily, laundry managers from all segments are realizing the potential for filtering and recycling wastewater for reuse as well as recouping thermal energy from wastewater, boiler exhaust and dryer/tumbler exhaust.
A variety of energy recovery systems that are designed for laundry use exist today. There are water reuse/recycling systems, such as Norchem’s Ultrapure and Wastewater Resources’ AquaTex 360°, that filter or otherwise remove contaminants from wastewater for its reuse. Equipment is available to recover a portion of the heat from boiler and dryer/tumbler exhaust, thus lowering heating fuel consumption.American Laundry News polled several companies that produce these types of equipment and asked about the criteria needed to justify installation, how their equipment addresses an individual laundry’s needs, what numbers are the most telling in terms of heat energy or water being lost or wasted, and whether laundry managers are truly aware of these potential money-savers.

Must a laundry facility be a certain physical sizeor process a certain number of pounds annuallyto justify installing energy conservation equipment?

Jeff Lebedin is the president of AquaRecycle, maker of a recycling system that reportedly reuses 100% of a laundry’s preheated wastewater. His company’s recent installations include a centralized hotel laundry processing 36 million pounds a year and a five-star hotel’s on-premise laundry processing 300,000 pounds per month.
“We estimate an average of around 3,000 pounds of laundry per day to justify the combination of water recycling/energy savings for our system. Of course, laundry environments using higher energy products, such as LP, may be less than this threshold.”
Al Jenneman is executive vice president of Kemco Systems. His company manufactures wastewater heat recovery systems, boiler economizers, direct-contact water heaters, water reuse and water recycling systems, and flash steam recovery.
Recent installations include hospital laundries, prison laundries, industrial uniform, dust control plants, linen processing plants and hotel laundries, he says.
“Two hundred fifty pounds per hour washed is probably the bottom, while 400 pounds per hour is where it becomes an attractive return on investment (ROI) in energy and water recovery.
“Our products are cost-effective at the smaller laundries that may be at 250 pounds per hour but operate two shifts at that volume. The more hours the laundry works, the faster the ROI.”
Ben Herschel is the president of Rototherm Corp., a maker of heat recovery equipment for laundry tumblers. Large institutional laundries and large hotel OPLs have installed his company’s equipment recently.
“(This is) directly dependent upon hours/days of operation of tumblers and fuel costs. Typically, equipment is most cost-effective on tumblers of 100 pounds and higher dry weight capacity, used a minimum of eight hours per day, five or six days a week.”
Mark Liberto is senior sales engineer for Ludell Mfg., maker of water heating and waste heat recovery systems. Recent installations include ARAMARK in Chicago and North Shore Linen in Long Island, N.Y.
“In regard to the size of plant for our heat recovery system, the smallest size is approximately 50 gpm (gallons per minute). We offer a wide range of sizes for the direct-contact water heaters.
Charles Harrigan III is the sales and marketing director for Industrial Waste Water Services (IWWS), producers of complete physical and chemical wastewater treatment systems to the textile rental and industrial laundry industries. Recent installations include Star Uniform Co. in Fort Worth, Texas, and Spirit Services in Bowling Green, Ky.
“We do not have a hard and fast lower limit on facility size. … For customers who are in compliance (with discharge limits) but seeking water reuse, water and sewer costs combined with water volume are used to perform a cost/benefit analysis. The types of washing equipment in use can affect reuse potential. Tunnel washers already reuse some of their own water, reducing the overall potential for water reuse in the plant.
“In general, a customer needs to use a large volume of water and pay greatly for it in order to justify a complete waste treatment system based on reuse alone.”

Is your equipment “one size fits all,”or is each project unique in its designand installation?

Jenneman: “We generally custom-design systems for economy and size. Each project is surveyed and the equipment proposal is based on product mix, utility cost and operating hours. The systems are made of standard components to best suit the application and meet ROI requirements. Sometimes, energy drives system design. In other locations, it may be the cost or availability of water.”
Herschel: “Equipment is generic, and presently offered in six size increments. ... Minor duct modifications are usually required for installation on OPL tumblers, along with our provision of ‘adapter plenums’ for each unit, providing larger OPL tumblers with a mounting surface for the heat recovery unit and also providing discrete supply airflow/recovered heat back to the tumbler.
“In the case of larger industrial tumblers, most of the jobs are substantial in size and sophistication, typically involving some engineering and design.”
Liberto: “All of our equipment is custom-engineered to the customer’s requirements.”
Harrigan: “We engineer each system to meet the unique needs of each customer. Every plant has a different product mix, different space availability and a different layout. We rely on thorough lab testing and on-site surveys to help design an effective system.”
Lebedin: “Our system is designed around the washing machine capacity of the laundry. We calculate a gallons-per-minute (gpm) size by using the total poundage of all washing machines times an average of three gallons per pound and a 45-minute washing cycle.”

When you are studying the operation of a potentialclient, what numbers are the most telling to you interms of heat energy or water being lost or wasted?

Herschel: “The most telling numbers are hours/day operation and fuel costs. Gas – natural, propane, etc. – is inherently the most efficient fuel for laundry drying. However, there are many steam-heated and electric-heated tumblers, and the inefficiencies and high costs resulting from steam production or inherent in using electric resistance heat provide proportionately shorter paybacks than those available from gas-fired tumblers.”
Liberto: “Wastewater temperature to sewer (and) boiler stack temperature.”
Harrigan: “Strictly in terms of water reuse, we look at the plant’s product mix to gauge the potential for reuse. The more products washed that do not come in contact with human skin, the greater the potential for reuse.”
Lebedin: “The temperature of the wastewater being sent to the drain is the best indication of energy and water lost and potential savings for our clients.”
Jenneman: “Pounds per hour processed, gallons per pound in the formulas, total daily water and gas consumption, hours of operation, and the cost of water and gas.”

Do you find that laundry managers are generallyaware of equipment options for heat recovery orwater reuse, or is it necessary for you to educateprospects about what’s available?

Harrigan: “Some managers are very aware and some are not at all aware of the issues surrounding water reuse and the options available. ... We believe in providing data to help the customer make an informed decision. We also rely on our current customers to talk to prospective customers.”
Lebedin: “It depends on the size and sophistication of the operation. Hotel OPLs tend to lack the knowledge, motivation and capital dollars to actively pursue and research energy-saving projects. The same with OPLs in hospital environments. Knowledge and energy savings equipment is much more prevalent in centralized laundries, commercial laundries that service the hotel and hospital environments as well as areas in the country where these energy costs are excessive and they have much longer winters.”
Jenneman: “The smaller laundries typically are less aware of the benefits and cost effectiveness of energy and water recovery. The large national chains are all aware of the equipment and the ROI potential. Most commercial and industrial plants employ the equipment already.”
Herschel: “In most cases, education is necessary. In addition, there is scant knowledge of the existence of rotary air-to-air heat exchange even within the engineering profession, not to mention the mature, pervasive laundry industry.”
Liberto: “Most laundry managers are aware of the equipment that is available but, with today’s high energy costs, need to be re-educated on the savings that are provided by the systems."

Have a question or comment? E-mail our editor Matt Poe at [email protected].