CASE STUDY No. 9717
KEY WORDS CITRIC ACID, PRODUCTION WASTE; MYCELIUM; CATTLE FEED
Haarmann & Reimer
1884 Miles Avenue
Elkhart, IN 46514
Contact: Dale Stickel, Environmental Engineer.
Tel: 219-264-8891. Fax: 219-264-8666
Summary
A program to reduce the amount of production waste being sent to landfill resulted in the conversion of 10,000 tons per year of waste mycelium biologic fermentation husk residue into cattle feed for use by local farmers. Cost savings and revenue increases totalling $584,000 per year are projected.
Background
Haarmann & Reimer (H&R) is a major producer of citric acid used in the production of such items as fruit flavored drinks, sodas, and orange juice supplement. In the early 1990s, H&R's parent company, Bayer Corporation, initiated a company-wide waste reduction program known as WRAM--Waste Reduction and Management. Mycelium landfill waste at H&R was soon identified as the fourth largest waste stream among Bayer's entire enterprise of more than 50 locations.
Mycelium is the residual husk of selected enzymes added to the citric acid production process to enhance biologic fermentation. Because of its low weight and "blowing" properties, H&R was paying a premium for hauling the waste and disposing of it in a landfill.
A major alternative to disposal was the use of mycelium as a supplement to cattle feed. In 1994, Bayer commissioned Purdue University to study the nutritional value of mycelium as cattle feed. The study concluded that 1 lb. of dry mycelium was the nutritional equivalent of 1 lb. of corn, assuming that mycelium did not exceed 30% of the total diet.
Other alternatives to disposal also were evaluated, including land application of mycelium as a soil nutrient; use of mycelium to remove small particle solids from wastewater in mining operations; composting; and decomposition of mycelium in anaerobic waste treatment reactors.
Because of the comparatively low price of feed corn at the time of its investigation, H&R had difficulty finding potential local buyers of mycelium as feed. But when feed corn prices rose, a major farm in lower Michigan expressed interest, agreeing to take waste mycelium free but to pay shipping costs. To increase solids from 20% to 40% dry basis, the farm company installed a filter press at H&R at its own expense. This cut the shipping weight in half, reduced shipping costs, and doubled the daily amount of wet feed which cattle could consume.
Payback
Bayer/H&R invested more than $1 million in the study performed by Purdue
University, as well as new equipment costs. But since implementation of the new program,
H&R has totally eliminated some 10,000 tons per year of mycelium from its waste
stream. Out of projected annual savings of $584,000, avoided landfill tipping fees alone
total $221,000. A payback period of less than 2 years is expected.