Thermal Treatment Technologies: Wet Air Oxidation
Wet air oxidation is a process in which organic matter in an aqueous solution can be oxidized and release heat, provided that oxygen is present under increasing pressure. With the passage of the Clean Water Act in 1972, and the requirements that it...
Thermal Treatment Technologies: Risks and Rewards of Thermal Destruction
Thermal destruction of hazardous wastes has much potential, but it has aroused much public concern, as well. Even the best such techniques are only safe and effective when they are controlled and done properly--something that is not always the case.
Physical Treatment Technologies: Electrostatic Precipitation
Particulate matter created as a result of burning coal may be too hot to draw through a baghouse. With an electrostatic precipitator, the hot, dirty stream of exhaust gas passes through a densely spaced series of plates. High voltage electricity c...
Introduction to Waste Stream Management: Block Flow/Mass Balance Analysis
The first step in controlling wastes is understanding where and how they are generated. Engineers and environmental managers use a tool called a block flow diagram to make sense of complex industrial processes. They also use a technique called mas...
Introduction to Waste Stream Management: Treatment Technologies and Pollution Sources
The approved EPA treatment technologies for solid, liquid and gaseous wastestreams can be categorized into four groups: physical, chemical, biological and thermal. Knowing which type of treatment to use and when to use it requires understanding the...
Natural Ecosystem Services and Waste Disposal
Paul Ehrlich, best known for his work on population growth, observes that there's no way to truly "throw things away," because everything remains on this planet. According to Dr. Ehrlich, we must depend on natural systems functioning properly if we ...
Introduction to Waste Stream Management: Overview and History of Pollution and Environmental Awareness
While pollution has always been part of the industrial process, environmental accountability is relatively new. The founding of the Environmental Protection Agency and the introduction of basic measures to standardize emissions and treatment of liq...
Introduction to Waste Stream Management: Liquid Waste
In the past, some of the major sources of water pollution have been landfills, underground storage tanks, and untreated effluent. Under the Clean Water Act, the EPA sets industry-specific discharge limitations for water pollutants. Treatment metho...
Sustaining the Earth: Case Study: Industrial Symbiosis
An examination of a symbiotic industrial arrangement among four industries in Denmark in which the wastes from one industry provide the raw materials for another. This kind of planned cradle to grave management of resources has positive economic, so...
The Metal Plating and Finishing Industry: Electroplating: Metal Finishes and Application Processes
Once the part has been cleaned, it is ready to receive the electroplating. One way of plating large quantities of small workpieces at the same time is by barrel plating. In this process, large, plastic barrels are filled with quantities of workpie...