Dairy plants are among the heaviest users of municipal water in the United States, using two gallons of water for every gallon of consumer product produced. The clean-in-place (CIP) systems that daily wash and sanitize every truck, tank, pipe and surface in the plant use the greatest amount of that precious water and waste the most as well. The cost of CIP water is high, because much of it has to be heated, chemicals must be added to it and cities levy charges for the use of municipal drain systems. A typical CIP system pushes water and chemicals through dairy plant equipment at 100–200 gallons per minute, although the required rate of flow (5–6 ft per second) across processing surfaces can be accomplished with much less water. Until recently, few companies even knew how long this flow should continue to ensure complete cleaning. It’s common for dairy manufacturers to deal with even minor quality problems that may be CIP-related by increasing time in each step of the CIP wash-and-rinse programs. Most of this water—and sometimes all of it—makes one pass through the equipment and then goes straight to drain. For each minute added to the wash in an attempt to correct quality, another 100–200 gallons of hot water go down the drain. In cleaning a typical dairy plant, three or four steps of each CIP program run water to drain.

 …