Team Reduces Water Use and Product Loss

MnTAP SOURCE, Spring 1999, Volume 14, Number 2
Minnesota Technical Assistance Program, University of Minnesota

Driven by a looming sewer access charge (SAC), Schroeder Milk Co., got organized. It formed a team which identified process improvements while talking over sandwiches.

Saved Over $400,000
When Schroeder Milk Co., St. Paul, learned the public wastewater treatment facility was going to assess them with a $200,000 SAC, it was driven to look for opportunities to reduce its wastewater.

Schroeder processes 90,000 gallons of milk daily and 8,000 gallons of orange juice weekly. They employ 80 people.

MnTAP helped the company form a pollution prevention team comprised of production personnel, warehouse workers and engineers. In two years, the team went from identifying problems and developing a game plan to implementing solutions and tracking results.

Schroeder's team identified several ways to reduce water use and product loss. The ideas saved the company over $400,000 through water and product savings and in reduced industrial fees. Lowering water use to 13 million gallons a year reduced Schroeder's SAC to $25,000.

The greatest challenge was finding time to look into improvements. Carl Schroeder, Jr., director of manufacturing, says, "Everyone at the company has a normal job that has to get done. This was added work." That's why the team met informally every other week during lunch, which the company bought.

Product Savings
Installing a second pasteurizer exclusively for white milk, reduced the number of changeovers between products. This saves $180,000 in product annually and 8,600 gallons of water a day.

An antifoam ingredient was added to the chocolate milk to prevent foam overflow, saving $187,000 annually in product.

Small Leaks Add Up
Repairing leaky hoses, connections and valves saved 1,440 gallons of product and 5,086 gallons of water a day.

Use Less
The team identified three cleaning processes that did not need a continuous water flow. Now, when wash water is needed for cleaning milk cartons, their carrying cases, or the conveyor of the carton filling machine, the wash systems are automatically triggered. Smaller nozzles and mist sprays were also added to the carton washer. These changed save 14,740 gallons of water a day.

The team identified processes where water use could be cut down without affecting product quality. The sanitizing time for the plumbing was reduced from four minutes to three, saving 1,250 gallons of water a day. The manufacturer recommended reducing water flow in the cream separator from 180 gallons per hour to 30. This saves 3,000 gallons of water a day. 

Reuse It
Schroeder had many opportunities for recirculating water and chemicals, instead of immediately discharging them down the drain.

Excess water from cleaning returnable plastic cartons is now sent to the washer that cleans the cases that hold them. This reduces the total amount of fresh water, chemicals and heat needed, saving 4,200 gallons of water a day.

The filling machines were cooled with water used only once. Schroeder switched to a recirculating water system, saving 10,000 gallons of water a day.

In one sanitizing stage, the acidic rinse is now recollected and used as prewash for the next cleaning cycle. This saves 100 gallons of chemicals and 500 gallons of water every day.

More Information
For the complete case study or additional information on waste reduction in the dairy industry and pollution prevention teams, call John Polanski, MnTAP, at 612/627-1906.