Iowa produces more than 500 tons of organic waste every day, equal to the weight of nearly 350 mid-sized cars, and researchers at Iowa State are exploring ways to recycle that waste.

Tom Richard, assistant professor of agricultural and biosystems engineering, is in charge of the team experimenting with creating compost out of the waste.

The waste is composed mainly of paper mill sludge and expended enzymes from stone-washing blue jeans and pharmaceutical production.

“We’re trying to take advantage of the unique properties of these materials so they complement each other instead of creating conflicts in the operations,” Richard said.

The research is intended to manipulate composting techniques, making a substance to enhance the soil, he said.

Another member of the research team, Matt Liebman, associate professor of agronomy, said the compost would improve not only the nutrients in the soil, but also the physical aspects of the soil such as aeration, water-holding ability and micro-organism activity.

“The idea is to get a really good blend for [each aspect of the soil],” Richard said.

One problem with synthetic fertilizers is they release their nutrients immediately after application, not when the crops need them, Richard said. This is what causes seepage of chemicals into the water supply.

“They are applied before the crop really needs them,” he said.

Part of the research team’s goal is to measure the rate of nutrient release during the growing season and how it can be controlled, Richard said.

This would allow the nutrients to spread into the soil for as short a time as possible before the crops need them.

“As the nutrients come available, the crop takes them up,” he said.

A past problem with composting has been the lengthy procedure to produce the compost, so this is being addressed by the studies, Liebman said.

Richard said researchers are trying to reduce the time needed for composting from six months to a year to about three or four months. They plan to accomplish this by controlling the temperature, moisture and oxygen concentration of the compost.

Farmers have used mostly synthetic fertilizers on crops since World War II because of its cost efficiency and ease of application, Richard said. He said that would change if an efficient and cost-effective procedure for composting was found.

Organic farmers are especially interested in the compost as fertilizer, and other farmers have shown interest in using a combination of organic and synthetic fertilizers in the near future, Richard said.

Richard said greenhouses, landscaping businesses and nurseries already are consumers of compost and will continue to be.

“This is a good way for Iowans to recycle agricultural waste products,” Liebman said.

Before composting was an option, the waste was put in landfills or burned, Richard said. He said his concern with the environment also was a factor in this research.

“All of these materials that … have been thought of as waste materials have some value,” Richard said.

Although the main focus of the research is agricultural uses, other applications, such as improvement of roadside reclamation, also are being explored, Richard said.

Also working on the research is Cynthia Cambardella of the National Soil Tilth Laboratory.