Use Nationally and in Massachusetts
U.S. manufacturers consumed 38 million metric tons (84 billion pounds) of sulfuric acid in 1993, making it the most widely used chemical (see Table 1).
- Producers of phosphate fertilizers are the largest end-user of sulfuric acid; they consume almost 75% of sulfuric acid in the U.S.
- Other large end-users include mining operations (ore processing), oil refiners (petroleum alkylation), chemical producers (caprolactum, methyl methacrylate, aluminum sulfate, hydrofluoric acid, ammonium sulfate, titanium dioxide, and surfaceactive ingredients), pulp and paper producers, battery manufacturers, plastics manufacturers, and iron and steel producers.
- Miscellaneous uses include water treatment, production of deionized water used in electricity generation, and chemical products (including hydrochloric acid, chrome chemicals, citric acid, boric acid, resorcinol, furfural, alcohols, and phenol).
Reflecting its versatility and wide use, 166 Massachusetts businesses used 45 million pounds of sulfuric acid in 1996 (see Table 2) in at least 15 different applications (see Table 3). In 1996, it was the second most frequently reported chemical, ranked fifth in total use, and ranked third in byproduct generation.
- Chemical manufacturers are one of the dominant users of sulfuric acid in Massachusetts. Chemical products manufactured using sulfuric acid include photographic gelatin, polyamide resins, polyvinyl butyral resin, sulfonated oils, electroplating baths, and photoactive chemicals.
- Two chemical distributors reported repackaging and distributing 6.6 million pounds of sulfuric acid in 1996, or 15% of the total reported that year. This industry sector was not required to report in 1990.
- Many industries use sulfuric acid in water and wastewater treatment processes, consuming at least 25% of the total used in Massachusetts. It is used to control pH and in the deionization of water. Industries that report the largest use for these purposes include: textiles, food and beverage processing, electronics, metals, and pulp and paper. The quantity used for waste treatment has, in many cases, been estimated from available data. Facilities are not required to separate out and report the amount used for waste treatment.
- Electricity generators are the third largest end-user; they consume 17% of all sulfuric acid in Massachusetts. Electric utilities use it to regenerate ion exchange resins, and they produce it incidentally in flue gas scrubbers.
- Massachusetts food and beverage processors used 2.9 million pounds of sulfuric acid in 1996. Kraft Foods dominates this use with 2.87 million pounds of sulfuric acid in the manufacture of edible gelatin.
- Electronics manufacturers used 2.1 million pounds of sulfuric acid in 1996 to produce printed circuit boards, semiconductors, and silicon wafers. Electronics producers use sulfuric acid in copper-sulfate baths and micro-etch solutions.
- Electroplaters and anodizers used 2.9 million pounds of sulfuric acid in 1996. Electroplaters use sulfuric acid to remove oxides from metals prior to plating (pickling) and in copper-sulfate and tin-sulfate plating baths. Anodizers use sulfuric acid to produce an oxide layer on aluminum surfaces and to remove smut from cast aluminum.
- Paper manufacturers used 2.1 million pounds of sulfuric acid in 1996 to control pH in processes including: deinking recycled paper, manufacturing cotton pulp, and treating water.
- Two industries that reported significant amounts of sulfuric acid use in 1996 were not required to report in 1990. In 1996, electric utilities reported 7.6 million pounds and chemical distributors reported 6.6 million pounds. If these industries are omitted from the analysis, there was a 28% decrease in sulfuric acid use from 1990 to 1996.
- Sulfuric acid use in food processing increased by almost 50%, due to a 30% rise in use by Kraft Foods and new uses reported by AgriMark, Cumberland Farms, and H.P. Hood. The latter three companies use sulfuric acid to clean process equipment.
- Sulfuric acid use in chemical products dropped by 57%. This change is primarily due to an aggregate decrease of 10 million pounds from 1990 to 1996 by three large facilities, only one of which still reported in 1996. The majority of chemical companies (15 out of 21) reporting decreased their use from 1990 to 1996.
- Electronics, textiles and leather, and metal pickling significantly reduced use of sulfuric acid from 1990 to 1996. Paper manufacturing increased use by almost 50%, due to approximately half the companies reporting increases and half reporting decreases.
Outputs of sulfuric acid were considerably lower than inputs because sulfuric acid is often consumed or transformed in the process. "Outputs" are measured by the Massachusetts Toxics Use Reduction Act (MA TURA) as product and byproduct. MA TURA output data include all non-product material created by a process line prior to releases, on-site treatment, or transfer ("byproduct") and the amount of toxic chemical incorporated into a product ("shipped in or as product"). Outputs of sulfuric acid rose slightly, by 6%, between 1990 and 1996.
- Sulfuric acid "shipped in or as product" appeared to increase by 43% primarily because of the addition in 1991 of chemical distributors to those that must report chemical use in Massachusetts. Astro Chemicals and Boremco Specialty Chemicals reported distributing 6.6 million pounds of sulfuric acidbased products in 1996 (as compared to 0 pounds in 1990). Offsetting this was a decrease from 3.4 million pounds shipped by Proctor and Gamble in 1990 to 0 pounds in 1996.
- Sulfuric acid "generated as byproduct" dropped by 8%. The trend in byproduct generation was influenced by facilities which stopped reporting sulfuric acid after 1990 (a reduction of 2.3 million pounds), and facilities which began reporting after 1990 (an increase of 4 million pounds, mostly from electric utilities). Those "consistent" facilities that reported in both years reduced their byproduct by 2.8 million pounds, or 25%.
Environmental releases and transfers of sulfuric acid in Massachusetts dropped by 12% between 1990 and 1996. The U.S. EPA, TRI output data include information on the waste materials generated by a facility after on-site treatment including: releases to air, land, and water ("environmental releases") and transfers off-site for treatment or disposal ("off-site transfers").
- Releases to the environment increased sharply due to the addition of electric generation facilities to the TURA reporting universe in 1991. Those "consistent" facilities that reported in 1990 and 1996, reduced their environmental releases by 18%.
- "Off-site transfers" fell sharply due to two large users reporting 1.3 million pounds of transfers to POTW's in 1990 only. This is likely due to a change in how they reported neutralized acids in the waste stream, rather than real waste reductions.
Stanford Research Institute (SRI) International, 1995, Chemical Economics Handbook, "Sulfuric Acid" (Palo Alto, California: SRI). The Massachusetts chemical use data are from the Massachusetts Department of Environmental Protection (MA DEP), 1998, "Massachusetts Toxics Use Reduction Act Chemical Reporting Data" (Boston: MA DEP).