U.S. Department of Energy - Energy Efficiency and Renewable Energy
Advanced Manufacturing Office
Dow Uncovers Ways to Turn Plant Wastes Into Useful Products, Save Energy and Money, and Curb Emissions
September 9, 2005
Forty Dow Chemical Company manufacturing plants at six Gulf Coast sites were the subject of a special study aimed at identifying synergies among the plants, such as reusing industrial wastes to create useful new products. At the same time, the plants would be saving energy and money and curbing environmental emissions.
In particular, the study found that Dow could reuse 155 million pounds per year of nonchlorinated waste by-products by implementing certain recommended projects. It also found that energy savings could be as much as 900,000 MMBtu per year, and that carbon dioxide emissions would be reduced by 108 million pounds annually. Potential annual cost savings were estimated to be at least $15 million.
In the study, Dow made use of the U.S. Business Council for Sustainable Development's By-Product Synergy process. This process brings clusters of facilities together to create closed-loop systems in which one facility's wastes become another's useful raw materials. Such synergies not only reduce waste, they also promote more efficient use of natural resources.
Four manufacturing sites in Texas were chosen for the study: Freeport, La Porte, Seadrift, and Texas City. Two sites in Louisiana were selected: Plaquemine and St. Charles. Within the six sites, the study focused on 40 manufacturing plants identified as major generators of nonchlorinated waste.
The recommended projects involve recovering hydrocarbons and spent solvents and reusing sodium hydroxide by-products, sulfuric acid waste, Methocel™ waste, ortho-toluenediamine, and by-product hydrogen. For example, several projects propose new on-site or external applications for medium-strength (~50%) sulfuric acid waste. One project would involve assessing the potential use of sulfuric acid waste to control the pH in wastewater treatment units; another would assess opportunities for using the waste in another industry—for example, converting it to ammonium sulfate for use in manufacturing fertilizer.
Dow provides chemical, plastic, and agricultural products and services to a variety of consumer markets.
To learn more, see the case study (PDF 218 KB). Download Adobe Reader.