Chemical Manufacturers Association (CMA)
The US chemical industry has reduced releases to air, land and water, transfers, and volumes disposed of through underground injection in all seven years that the Toxics Release Inventory has been compiled.
An analysis of TRI reports by the Chemical Manufacturers Association shows that its member companies cut releases to the air and land by 47 percent and to water by 81 percent. Off-site transfers for treatment and to publicly owned treatment works were down by more than half from 1987 to 1993, and transfers for land disposal were reduced by nearly 70 percent. Carcinogens and EPA's priority chemicals were reduced as well. CMA member companies represent more than 90 percent of US productive capacity for basic industrial chemicals.
Releases and Transfers by Media (Millions Lbs.)
| Media | 1987 | 1988 | 1989 | 1990 | 1991 | 1992 | 1993* | % Change |
|---|---|---|---|---|---|---|---|---|
| Air | 543 | 501 | 479 | 408 | 378 | 340 | 286 | -47% |
| Water | 37 | 20 | 13 | 9 | 9 | 7 | 7 | -81% |
| Land | 47 | 52 | 35 | 32 | 30 | 31 | 26 | -45% |
| Total Releases | 627 | 573 | 527 | 449 | 417 | 378 | 319 | -49% |
| Treatment | 220 | 214 | 177 | 148 | 157 | 106 | 99 | -55% |
| Land Disposal | 61 | 50 | 38 | 38 | 32 | 31 | 19 | -69% |
| Publicly Owned Treatment Works | 162 | 139 | 135 | 134 | 113 | 109 | 77 | -52% |
| Total Transfers | 443 | 403 | 350 | 320 | 302 | 246 | 195 | -56% |
| Underground Injection | 675 | 665 | 544 | 426 | 421 | 425 | 365 | -46% |
| * Projection based on a survey of 55 companies that account for 90% of the TRI releases and transfers reported by CMA member companies. ** Excludes transfers for recycling and energy recovery, reported for the first time in 1991. | ||||||||
Many CMA companies have directed their pollution prevention efforts to reducing air emissions, since they are the largest TRI release and offer the greatest potential for human exposure. Union Carbide, for example, set out in the 1990's to reduce more than 5 million pounds of acetone releases from its plant in Texas City. The first challenge was to identify the emissions from leaking valves and pipes -- no easy task since the facility covered four city blocks and included hundreds of pieces of equipment. Once the sources were identified, a combination of equipment and process changes coupled with workforce training reduced emissions by 2 million pounds the first year and by another million pounds the next year.
Cabot Corporation and Hercules Incorporated have ambitious goals to cut air releases by 90 percent at plants in Tuscola, EL, and Magna, UT, respectively. Cabot installed a methane injection system to convert more than 4 million pounds of chlorine waste to hydrogen chloride, a salable product, and Hercules phased out the use of methylene chloride and trichloroethane as sizing solvents. Exxon Chemicals Tomah Products plant in Milton, WI, also reduced air emissions by 90 percent in a two-part program that included upgrading the ammonia recovery system and installing a cryogenic condenser to remove and recycle 99 percent of the methyl chloride and ethylene oxide in the vent gases.
Ethylene oxide belongs to a category of chemicals which CMA companies have given priority to reduce. Of CMA's 320 core chemicals, 44 are known or suspected human carcinogens. They account for less than five percent of total releases and transfers reported by CMA member companies. Among the carcinogens are heavy metals such as cadmium and chromium. These carcinogens were found in pigments used by ICI Americas to color plastic resins. The company spent two years to develop alternate pigment systems free of heavy metals. The result was a reduction of 96 percent in cadmium-laden pigment waste to landfills.
Cadmium is also a "33/50" chemical. These are 17 priority chemicals that EPA asked industry to voluntarily reduce. CMA member companies exceeded the interim goal of 33 percent in 1992 and should achieve the 50 percent reduction two years ahead of time. For instance, Monsanto recovered better than 90 percent of toluene in air emissions at one plant and more than a million pounds of xylene at another. Both are 33/50 chemicals. W.R. Grace also recovered xylene at its plant in Bedford Park, EL, through process improvements, recycling and sale. Akzo Nobel cut releases and transfers of toluene, used to reduce the formation of gummy solids in scrubbers, by substituting a by-product produced at its Deer Park, TX, plant.
Water releases are the smallest volume reported for the Toxics Release Inventory, but they have been reduced by the largest percentage. Ethyl Corporation reduced 700,000 pounds of hydrochloric acid emitted to water by recycling the waste acid from one production unit to another. Ashta Chemicals, Ashtabula, OH, installed a closed loop cooling system to eliminate discharges to Lake Erie contaminated with mercury and solids. Process streams and stormwater are collected and purified, using reverse osmosis, and recycled. Sterling Chemicals reduced wastewater volatile organic releases by 94 percent with the startup of a new, totally enclosed, above-ground wastewater treatment plant at its Texas City facility. Following a study at its St. Gabriel, LA, plant, Ciba-Geigy formed a preventive maintenance program that significantly reduced wastewater contaminated with acid and hydrogen cyanide.
At another site, Ciba-Geigy was faced with three different types of waste generated in making an intermediate for optical brighteners -- chemicals in laundry detergents that make the whites whiter and colors more vibrant. Ciba eliminated two of the wastes, one released to water, the other to land, and reduced the third by 70 percent. Dow Corning faced a similar challenge. The company manufactures silanes, intermediate chemicals used to make silicone products, including household sealants. The process generated 3 million pounds of waste, which was disposed of in wastewater and in landfills -- 6,700 cubic yards per year. Dow Coming introduced separation and recovery technologies that reduce dissolved solids by 83 percent and waste going to landfill by 98 percent.
Underground injection is the largest volume reported for the Toxics Release Inventory. Underground injection is actually a disposal technology, in which highly diluted liquid wastes are injected into EPA permitted wells, drilled deep into special geologic formations that contain and in some cases neutralize the waste. The Agency considers Class I underground injection wells "safer than virtually all other waste disposal practices."
The volume of waste injected underground declined substantially in 1993, after remaining flat for the previous three years. Cytec Industries Fortier plant in Westwago, LA, converted an onsite sulfuric acid plant to regenerate spent sulfuric acid. This process change reduced underground injection by 70 percent from 1990 levels. DuPont reduced the injection of ammonia and ammonium sulfate, by 65 percent at its Beaumont, TX, plant. The company also closed a deepwell used by its Louisville, KY, Works to dispose of hydrochloric acid. Cabot Corporation also significantly reduced the disposal of hydrochloric acid by its Charleston, IL, plant.
Vulcan Chemicals, Wichita, KS, reduced hydrochloric acid that went to deepwells by 73 percent from 1992 to 1993. Another Wichita plant, Air Products, also cut hydrochloric acid disposal, as did PPG Industries, Barberton, OH. In an interesting twist, PPG strengthened the waste hydrochloric acid and was able to sell it.
Last Updated: March 5, 1996