ANALYZING WHAT’S RECYCLABLE IN C&D DEBRIS

Ken Sandler

BioCycle November 2003, Vol. 44, No. 11, p. 51

CONSTRUCTION and demolition (C&D) debris keeps rising higher on the national radar screen, but sorting out the data is a tricky task. Here at the Environmental Protection Agency in Washington, D.C., we took our first stab at analysis in 1998, with the Characterization of Building-Related Construction and Demolition Debris in the United States. Lacking survey data, we aimed at extrapolating national estimates of building related C&D debris by multiplying numbers of buildings being constructed or demolished (based on permits issued) by amounts of debris estimated to be generated per square foot (based on waste composition studies that had been performed at various sites). Renovation figures were derived from estimates of consumer and business spending on specific remodeling and replacement activities.

SOIL QUALITY FUNDAMENTALS — WATER AND AIR ESSENTIALS

Richard Stehouwer, BioCycle November 2003, Vol. 44, No. 11, p. 30

SOILS have four components – air, water, mineral solids and organic solids. Air and water occupy the pore spaces formed by the solid particles and aggregates of solid particles. Despite their transient nature, air and water are essential to the life and activity that occur within soils. In fact, it is the relative distribution of air, water and solids that largely determines the qualities, and quality, of the soil. It is commonly said that the ideal combination of these components is 25 percent air, 25 percent water, 45 percent mineral solids and five percent organic solids. However, the air and water in soils are neither constant nor stationary. Both are continually removed, added and changed by soil and environmental processes. The soil serves as a channel and sink for water and air from earth’s surface and subsurface.

ARRESTING CORROSION IN COMPOST STRUCTURES

Rhonda Sherman

BioCycle November 2003, Vol. 44, No. 11, p. 45

WHEN SCIENTISTS test materials in a corrosion chamber, they create a warm, damp environment that is much like that inside an enclosed composting facility. "When a building is fully-enclosed, you create your own environment inside," says Web Chandler, a metallurgical engineer with Greenman-Pedersen, Inc. "If there is 100 percent relative humidity inside the building, it will be foggy. It is called an ‘immersion environment,’ which would be the same if you put steel under water." Add ammonia and bacteria to the moist composting environment and you have the perfect conditions for advanced corrosion, which can prematurely end the usefulness of buildings and equipment, or eat up an entire maintenance budget.

HOW PEOPLE SENSE, PERCEIVE AND REACT TO ODORS

Pamela Dalton

BioCycle November 2003, Vol. 44, No. 11, p.26

WHAT is fascinating about human olfaction, our sense of smell, is how much we underappreciate it. We often fail to recognize just how much information we obtain from our environment by using our noses, even when we are not consciously aware of it. Smell is the oldest and most sophisticated sensory system that mammals have for detecting information about their environment at a distance. The senses that we now consider most dominant for humans — vision and hearing — evolved much later. Even single celled organisms possess the ability to "smell," or sense chemicals.

FINANCIAL HELP FOR NEW DIGESTERS AND ETHANOL PLANTS

Josh Alban

BioCycle November 2003, Vol. 44, No. 11, p. 57

HIGH up-front capital costs have long been a serious obstacle for farmers looking to develop new revenue streams. This is especially true for farmers looking to use waste products as a feedstock for renewable energy production, where moderate to substantial infrastructure additions or modifications are often par for the course.

ANAEROBIC DIGESTERS IN MANURE MANAGEMENT

Philip D. Lusk

BioCycle November 2003, Vol. 44, No. 11, p. 55

AGRICULTURE in the U.S. produces more than 350 million tons of manure every year, and some farms have become so large that they cannot efficiently dispose of the enormous amounts of manure created. A recent USDA report states that only 18 percent of large hog farms and 23 percent of large dairy farms are applying manure on enough cropland to meet a nitrogen-based standard to protect water quality.

FROM SOLID WASTE MANAGEMENT TO SUSTAINABLE ECONOMY

Neil Seldman
BioCycle November 2003, Vol. 44, No. 11, p. 60

THE PERCENTAGE of discarded materials recycled has soared from five percent (eight million tons) in l968, to 30 percent (75 million tons) today. In some industries such as automobile, paper and cardboard, recycled materials comprise a majority of feedstocks used in new products.

PREVENTING FIRES IN GRINDING EQUIPMENT

BioCycle November 2003, Vol. 44, No. 11, p. 41

EQUIPMENT-wise, 2002 was not such a good year for Gro-Bark (Ontario) Ltd., a composted bark and soil amendment company based in Waterloo, Ontario. On June 1st, a tub grinder with about 300 hours of operating time, caught fire and was destroyed. A temporary replacement grinder was brought in and three weeks later, in the middle of the night, a fire started on an incline conveyor that was being used with the grinder. While not destroyed, the grinder was damaged.