This industry classification includes establishments engaged in manufacturing alkalies and chlorine. Examples of products include compressed or liquefied chlorine, sodium or potassium hydroxide, sodium bicarbonate, and soda ash (not produced at mines). Alkalies produced by mining are classified in SIC 1474: Potash, Soda, and Borate Minerals.
325181 (Alkalies and Chlorine Manufacturing)
The two primary commodities offered by the alkalies and chlorine industry are chlorine and sodium hydroxide (caustic soda), together representing about 82 percent of all shipments. Soda ash, an alkali product used in glassmaking, water treatment, pulp bleaching, and detergent manufacturing, accounts for only 14 percent of shipments. Other products account for the remaining 4 percent.
Chlorine and caustic soda have consistently appeared on lists of the top 10 U.S. chemicals according to production weight. They are co-products of the same chemical process. This means that they are created at the same time and that the production of one results in the production of the other. Although there are several modern procedures used to produce chlorine and caustic soda, most rely on a technique called electrolysis. As electricity is passed through brine (a salt water solution), the brine's components, salt (sodium chloride) and water (made up of hydrogen and oxygen), recombine to form chlorine and sodium hydroxide (caustic soda) in approximately equal amounts. Some hydrogen gas also results from the process.
Organic chemical manufacturers are the primary chlorine users in the United States. Some examples of chemicals produced with chlorine are ethylene dichloride, carbon tetrachloride, and methylene chloride. These and other chlorinated organic chemicals are used to make many products, including flame retardants, herbicides, solvents, refrigerants, polyvinylchloride (PVC) pipe, and pigments. The second-largest chlorine user is the pulp and paper industry, which uses chlorine as a bleaching agent. Chlorine products are also used as raw ingredients in household and commercial bleaches, scouring powders, and automatic dishwashing compounds. Other chlorine uses include water treatment, sewage treatment, sanitizing, and metal extracting.
Caustic soda has a wide range of industrial applications. It is used in petroleum exploration and by water treatment facilities, tanneries, and the textile industry. It also plays a role in food processing, metal fabrication, and chemical manufacturing. Caustic soda is also used in industrial complexes to remove boiler scale.
According to U.S. Department of Commerce statistics, shipments within the alkalies and chlorine industry totaled $2.3 billion in 2001, down from $2.5 billion in 1997. Despite the recent downward trend, the industry more than doubled between 1987 and 1997. The industry became volatile during the early 2001 as the U.S. economy became sluggish, and demand for chlorine and alkalies fell off. By 2003, the industry was beginning to show signs of recovery.
Conditions within the chlorine segment of the industry affected other products. Because caustic soda is a co-product of chlorine, cuts in chlorine production lead to shortages and higher prices within the caustic soda market. Caustic soda, following an upward trend in natural gas prices, was priced between $190 to $220 per ton in April 2003. Although soda ash has been manufactured synthetically from the evaporation of brines, it is primarily produced from trona, a mined product. The last synthetic soda ash facility in the United States closed in 1986, idling 700,000 tons of capacity. Operators closed the plant because it could not produce soda ash at prices low enough to compete with the trona-reliant process. Almost half of the domestic production of soda ash is used by glassmakers.
Approximately 99 percent of the chlorine and alkali chemical manufacturers in the United States and Canada belong to the Chlorine Institute, a group founded by 10 industry leaders in 1924. Although its original purpose was to further the demand for chlorine, its focus shifted to providing the industry with supervision and direction following a destructive hurricane in 1926 that wrought havoc on Florida's water treatment facilities. Thousands of chlorine cylinders were shipped to the state to aid in restoring safe water supplies, but many could not be used because the industry had no previously adopted standardized fittings. The emergency chlorine supply sat idle until adapters and valves could be obtained.
As a result of this experience, the group initiated a study of valve and fitting designs and recommended a standard that was voluntarily adopted by producers. Federal officials later relied on information from the Chlorine Institute in establishing standards for all compressed gases.
The Chlorine Institute also began working on programs to improve the safety record of the industry. In the 1930s an informal policy was established for responding to emergencies. Later the institute developed a formal program called CHLOREP (Chlorine Emergency Plan). CHLOREP consisted of volunteer teams available to respond to chlorine emergencies 24 hours a day, seven days a week. By 1991 the Chlorine Institute had trained 250 CHLOREP teams composed of members from more than 40 companies, and they were placed at more than 100 locations throughout the United States and Canada.
In addition to establishing standards and emergency response programs, the Chlorine Institute has published a wide range of manuals, pamphlets, and audiovisual materials to provide technical and safety information. The group has also worked on behalf of its members with the government agencies responsible for regulating various aspects of chemical production and shipment such as the Department of Transportation (DOT), the Interstate Commerce Commission (ICC), the Coast Guard, and the Occupational Safety and Health Administration (OSHA).
The use of chlorine compounds in chemical processes dates back to at least 77 A.D., but the isolated element itself was not produced until 1774. Although chlorine is a common element, in nature it exists only in compounds because it reacts readily with other substances, both organic and inorganic. For example, ordinary table salt, or sodium chloride, consists of chlorine and sodium.
A Swedish chemist, Carl Wilhelm Scheele (1742-1786), is acknowledged as the first person to create and identify chlorine. Scheele (who also co-discovered oxygen) generated a greenish-yellow gas during experiments with sea water. He called it "dephlogisticated marine acid air." The word "dephlogisticated" referred to the fact that it was not susceptible to combustion. The phrase "marine acid air" identified the new gaseous material produced from the acid obtained from marine brine. In 1810, when Sir Humphry Davy (1778-1829) used electricity to prove that the gas was an element, he coined the word "chlorine" from chloros, the Greek word for greenish yellow.
The bleaching effects of chlorine were first put to commercial use by textile makers in France near the end of the eighteenth century. Natural cottons and linens were light brown and required bleaching before they could be dyed with light or bright colors. Traditionally this had been accomplished by spreading the fabrics out and exposing them to the sun. Bleaching fabrics in this manner took as long as three months for cotton and as long as six months for linen. Chlorine bleaching compounds enabled textile manufacturers to keep up with the increasing speed of production that followed improvements in spinning and weaving methods.
Chlorine products were greatly improved by technology during the late eighteenth and early nineteenth centuries. In 1792 a process for bleaching rags used in paper making was developed. Bleaching powder, or calcium hypochlorite, was first introduced in 1799. The ability to transport chlorine to markets distant from manufacturing plants was achieved through the formation of potassium hypochlorite, a liquid product created with chlorine and caustic potash.
The development of chlorine production based on electrolysis lowered chlorine prices and increased the chemical's popularity. Electrolysis methods evolved through the mid-nineteenth century and, by the century's close, had become commercially viable in areas with low-cost electricity. The first commercial plant in the United States opened in Rumford, Maine in 1893.
As the twentieth century began, chlorine was being used for an increasing number of purposes. Jersey City, New Jersey was the first city to use chlorine to disinfect drinking water supplies. It began chlorination in 1908 and was soon followed by other major cities, including New York. Sewage treatment methods based on liquid chlorine were first adopted in Altoona, Pennsylvania, in 1913. The use of chlorine by water and sewage treatment facilities helped virtually eliminate diseases such as cholera, typhoid, and dysentery.
Not all of chlorine's uses, however, were benevolent. During World War I, chlorine gas, an extremely poisonous substance, was used as a weapon against the Allies. Despite the horrors associated with chlorine gas, the U.S. chlorine production industry benefited from the war. Imports of chemicals from Europe were sharply curtailed because of submarine warfare. As a result, domestic production tripled and continued to grow after the war. Chlorine has also played a role in the development of insecticides, anesthetics, dry cleaning fluids, and firefighting compounds. The fledgling plastics industry relied on chlorine to make its vital vinyl chloride products. Between 1955 and 1970, chlorine usage grew approximately 5.8 percent per year.
The 1970s ushered in an era of changes. Although the decade closed with chlorine production at a historic high, growth stagnated. Environmental questions hampered producers, and economic woes diminished demand by users. By the early 1990s, chlorine production and demand were still less than they had been in 1979.
Despite improvements lessening the environmental impact of chlorine and caustic soda production, the industry continued to suffer from adverse publicity concerning chlorine use. Chlorine compounds react with organic substances to form dioxins, which are suspected carcinogens and pose potential health hazards including birth defects and damage to the human skin, liver, neuroendocrine system, and immune system.
Controversy about dioxins affected usage by pulp and paper producers, one of the largest chlorine-consuming industries. Chlorine was traditionally used to bleach pulp and create white paper products. Increasingly, manufacturers were turning to innovative oxygen and hydrogen peroxide bleaching technologies. Analysts estimated that the pulp and paper industry used only about 9 percent of the domestic chlorine production in 1994, a drop from 15 percent in 1990.
Environmental groups increasingly protested the use of chlorine in other areas as well. Chlorofluorocarbons (CFCs) are suspected of damaging the ozone layer of the earth's upper atmosphere. Chlorinated solvents were considered a source of air pollution because of their emissions. In addition, some water treatment facilities began turning away from chlorine to other methods of water purification. According to the Chlorine Institute, however, calls to eliminate chlorine are unreasonable because of the heavy financial burden of meeting such restrictions.
Despite the problems associated with chlorine and its declines in traditional markets, industry analysts anticipated overall demand to grow and prices to increase as much as 15 percent by 2002. Vinyl exports and PVC use in new construction and in remodeling were expected to make up for the declines in other areas.
Soda Ash. In the 1990s, the global soda ash industry saw many non-U.S. companies acquire U.S. producers. For example, Solvay, the world's largest soda ash producer (headquartered in Brussels), purchased Tenneco's soda ash division in 1992. As a result of the acquisition, Solvay controlled almost half of U.S. soda ash production and was positioned to expand in the Asian Pacific and Latin American markets. By 1997 a Korean company, OCI, also entered U.S. soda ash production, operating the Big Island Mine and Refinery in Green River, Wyoming.
Humanitarian Aid. In early 1997, PPG Industries donated 11 million metric tons of calcium chlorite, and Olin Corporation donated an additional 1 million, for a total of 12 million metric tons to help residents of Cuba still recovering from the effects of Hurricane Lili, which struck the island in October 1996. The calcium chlorite was for use in disinfecting drinking water.
Modern methods of chlorine production were developed around electrolysis. The three most-used technologies—diaphragm cells, mercury cells, and membrane cells—produce chlorine and caustic soda by decomposing brine (salt water). Combined, they accounted for 97 percent of U.S. chlorine production in 1997. Other methods in operation in 1997 included electrolysis of either molten magnesium chloride or molten sodium chloride; electrolysis of hydrochloric acid; and non-electrolytic processes. The brine used as a raw material is obtained from natural deposits under the earth's surface or is made from salt and water.
Diaphragm cells, the oldest and most widely used of the modern methods, produces more than three-quarters of the nation's chlorine. Direct current is used to separate salt and water into chlorine, hydrogen, and sodium hydroxide (caustic soda). An internal asbestos fiber-coated device called a "diaphragm" keeps the chlorine and caustic soda separate. Manufacturers rely on additional evaporation and drying procedures to create products in marketable concentrations.
Mercury cells accounted for 12.1 percent of U.S. chlorine production in 1997. They employ a different technique for keeping manufactured chlorine and caustic soda separate. Because of the presence of mercury during the application of the cell's electric current, the sodium is isolated and dissolved into the mercury. A secondary process recaptures the mercury and releases the sodium to form sodium hydroxide (caustic soda). During the early 1990s producers were moving away from mercury cells because of environmental concerns surrounding the mercury content of plant waste water.
The membrane cell accounted for only 9.5 percent of U.S. chlorine production in 1997 but is the most rapidly growing production technology, using an ion exchange membrane to separate the chlorine and caustic soda. Membrane technology requires less electricity and produces grades of chlorine and caustic soda with higher purity than other methods.
The remaining 2.6 percent of U.S. chlorine capacity was contributed by alternate methods. By comparison, in Canada diaphragm cells retained their role in 85.3 percent of the production capacity, with membrane cells at 11.9 percent and mercury cells at 2.8 percent of the total.
It is of interest to note that, in both nations during the period 1988-1997, there was a decrease in the percentage of total chlorine production capacity contributed by mercury cells, with corresponding increases in the percentage of membrane cells in operation. This change was most dramatic in Canada, where the decrease was 12.5 percent. The decreases reflected continuing concerns about the hazards involved in use of mercury and its potential adverse environmental impact. The relative contribution of diaphragm cells remained virtually unchanged in the United States and slightly increased in Canada (4.6 percent).
Chlorine Packaging Plants in the United States. In 1997 there were 27 different companies in the United States operating a total of 86 chlorine packaging plants. One additional plant was shut down in November 1996; it had been operated by Jones Chemical in Henderson, Nevada. In contrast, there were only three such companies in Canada operating a total of seven plants, and four in Mexico, each operating one plant.
Chlorine and Caustic Soda Producers. In 1997 there were 24 companies in the United States operating 45 chlorine production plants with a total production capacity of 39,558 tons per day. By comparison, the seven Canadian plants had a daily production capacity of only 11 percent of the U.S. figure (3,561 tons per day), while the five operating Mexican plants were at 1.3 percent of U.S. capacity (529 tons per day).
Five companies either completed or were engaged in plant expansions and modernization in the United States as of late 1996—Dow Chemical, Occidental Chemical, Formosa Plastics, and a joint venture between Olin Corporation and Geon.
Figures released by Dow Chemical for 1996 showed their global chlorine production capacity at 11.5 billion pounds per year and global caustic soda production capacity at 12.5 billion pounds per year. About 50 percent of the caustic soda produced was sold, generating global sales of $500 million in 1996. A plant expansion in Freeport, Texas, in late 1996 increased Dow chlorine production capacity by 440 million pounds (200,000 metric tons) per year. The company heralded its first ever commercial use of membrane cell technology in its plant expansion in Stade, Germany, which added additional capacity of 260 million pounds (118,000 metric tons) per year. These increases were earmarked for the company's internal chlorine demand, which consumed over 95 percent of the chlorine generated.
Of Dow Chemical's total chlorine production in 1996, approximately one-third was directed toward production of 10 billion pounds of ethylene dichloride (EDC), which in turn was used for synthesis of vinyl chloride monomers (VCM). The latter were sold to other companies principally for production of polyvinyl chloride (PVC). An additional one-third of the chlorine production was directed towards synthesis of propylene oxide, with production of 3 billion pounds per year reported in 1996. Roughly 25 percent of this was destined for synthesis of propylene glycol, important in products such as aircraft de-icing fluids. The remaining one-third of Dow's chlorine production was used for production of other chlorinated compounds.
Occidental Chemical (Oxychem), the second-largest producer, but largest merchant marketer of chlorine and caustic soda, reported that it had completed expansions and improvements at several of its chlor-alkali facilities. Since 1993, Oxychem's U.S. chlorine production capacity was increased by 400 tons per day, with plans to add 600 tons per day additional capacity at three Gulf Coast plants, where the bulk of its production was concentrated by the end of 1998. This was slated to bring the total domestic capacity to roughly 9,000 tons per day. About 60 percent of the company's chlorine production in 1996 was directed toward its vinyls product chain, including EDC and VCM, ultimately used to manufacture PVC. The vinyls chain was the largest and most rapidly growing market for Oxychem's chlorine.
According to the U.S. Department of Commerce, chlorine capacity remained fairly stable from 1991 through 1996, with a general upward trend beginning in 1995. By 1996 the U.S. capacity (38,416 short tons per day) had slightly surpassed the 1985 value (38,298 short tons per day) but not yet returned to the 1980 level (39,391 short tons per day).
Statistics released by the Chlorine Institute revealed an overall trend toward increased domestic U.S. production of chlorine gas (and its alkali co-product) as well as the amount liquefied from 1991 through the start of 1997. Chlorine production for 1991 and 1996 was, respectively, 11,489,896 and 13,168,384 short tons. Equivalent values for liquefied chlorine were, respectively, 9,340,125 and 10,179,100 short tons. For the same period, liquid sodium hydroxide production was 12,151,285 and 13,856,531 short tons per year, respectively. The amount of dry sodium hydroxide produced during these years, although only a small percentage of the total, actually decreased from 266,137 short tons per year in 1991 to a value of 183,062 in 1996, a low of 173,925 short tons having been reached in 1995. By comparison, dry sodium hydroxide production was considerably greater in 1980 at 418,178 short tons. For the first two months of 1997, there were slight increases over the same two months of 1996 in production of chlorine and both liquid and dry sodium hydroxide.
Figures released by the U.S. Bureau of Census for the chlor-alkali industry in 1995 showed domestic total production at $3.3 billion in shipments, with contributions to this total from chlorine (compressed or liquefied) at $849.7 million, sodium hydroxide or caustic soda at $2.06 billion, and other alkalies at $382.3 million.
Prices for chlorine increased by $25 to $40 per ton at the end of 1996 and again in early 1997, by Dow, Occidental, and Vulcan. Increases were caused by (1) previous expansions in downstream production of chlorine derivatives not having been matched by corresponding expansions in chlor-alkali plants, with demand thus exceeding supply; (2) failures at two Dow chlor-alkali rectifiers (Freeport, Texas), with resultant production delays due to repairs; (3) a 30-day loss of production at the LaRoche Industries Gramercy, Louisiana plant, caused by a fire that caused a daily 50 percent reduction in the normal 300 tons per day output; and (4) the seasonal spring increase in homebuilding, with its attendant increase in demand for PVC products.
Caustic Soda. During the first quarter of 1997, caustic soda prices continued to decrease with prices reported in February at about $95 per ton on the Gulf. Although caustic soda prices dropped $100 per ton in the year from early 1996 to early 1997, it was believed by April 1997 that prices had bottomed out. Severe flooding in the Midwest, limited transport on the Mississippi River due to elevated levels, the Dow and LaRoche production problems, and other unforeseen difficulties during the first quarter helped to stabilize prices in part by their effects on caustic soda inventories. By 1998 the Dow plant at Freeport, Texas, was producing 4.5 million short tons per year of caustic soda with an increase of 325,000 short tons in capacity added in late 1999. In 1998 Bayer began building a plant at Baytown, Texas, to produce 1,065 tons per day of caustic soda. OxyChem generated almost 3.2 million short tons of caustic soda in 1998 at its facilities in Texas, Louisiana, Alabama, New York, and Delaware, and PPG followed with 1.9 million short tons at two plants in Louisiana and West Virginia.
Demand for caustic soda increased from 13.9 million tons in 1997 to 14.2 million tons in 1997 and was expected to climb to 15.7 million tons by 2001. Two percent growth per year was predicted through 2001, and the 1998 price per ton was $300.
EPA Limits On Toxic Pollution. In 1994 the Environmental Protection Agency announced that chemical companies in the United States would have to cut their manufacturing plants' toxic air pollution by almost 90 percent from 1990 levels. The rule, noted the Detroit Free Press, "requires the companies… to install equipment to better prevent evaporation and leaks of 112 toxic chemicals…. About 370 chemical plants in 38 states willbe forced to cut toxic air pollution by a total of 506,000 tons, an EPA statement said." While the new rules, instituted as a part of the 1990 Clean Air Act, would involve significant expenditures on capital improvements for the affected companies, regulators noted that chemical companies have already taken significant steps to address the new requirements in anticipation of the announcement.
Hydrogen Peroxide. Environmental issues continued to affect the worldwide chlorine industry in 1997, matters that were clearly reflected in the peroxide market, which is linked to the pulp and paper market. Due to excessive pulp inventories in 1996, pulp prices declined. Prior to the crash, peroxide growth was forecast at 10 to 12 percent annually through 2000, but afterward, at only 5 to 8 percent.
EPA regulations provided the initial impetus for increased hydrogen peroxide demand in the pulp and paper industry. These regulations prompted conversion of pulp mills from elemental chlorine use to either chlorine dioxide (which may be generated, in turn, from sodium chlorate) or hydrogen peroxide.
By the beginning of 1997, most U.S. pulp plants had stopped using elemental chlorine for bleaching and substituted chlorine dioxide to eliminate dioxin production. During the same period, a bill was introduced in Congress to force U.S. pulp plants to use totally chlorine-free (TCF) bleaching processes, a move favored by many environmentalists as a means of reducing dioxin pollution. The EPA was therefore debating between two possible rules—to either allow chlorine-based plants to substitute chlorine dioxide or to require partial substitution of chlorine dioxide with oxygen. The Chlorine Chemistry Council and paper workers' unions supported the shift to chlorine dioxide, arguing that partial substitution of oxygen would be very costly (perhaps $1 billion), and the expense would potentially eliminate thousands of jobs.
As of early 1997, the Canadian pulp industry was believed to have substituted other materials for elemental chlorine in 89 to 90 percent of its operations, with the United States lagging behind at perhaps only 45 percent. Worldwide, Scandinavian pulp producers adopted total chlorine-free (TCF) substitution due to pressure from the Green Movement in Europe. Of related interest in 1997 were proposals to the European Commission by EUROCHLOR (an industry group of European chlorine producers) for new air and water emissions standards for mercury-based chlor-alkali production processes. Proposed limits for air and water were 1.9 grams of mercury per metric ton of chlorine produced. Final legislation will take effect in 2005.
The trend away from chlorine use was highly beneficial for the peroxide market, and by 1996 the six producers in North America (DuPont, Solvay, Degussa, Chemprox, FMC, and Eka Nobel) were gearing up for plant expansions to increase North American capacity to roughly 2 billion pounds by 1998, an increase of more than 800 million pounds over previous levels.
Chlorine and caustic soda started off the twenty-first century under duress. The downturn in the economy led to a decrease in demand, forcing prices down. Suffering from degrading sales in the pulp and paper industry, spot prices of caustic soda were running between $165 and $175 per ton in the fall of 2001, approximately half of the selling price in January 2001. Contract prices were between $190 and $220 in November 2001, reflecting a price decrease of $50 per ton since September. Chlorine production during 2001 was down 10 percent, reflecting the lowest production levels in 20 years. Also affecting the market was a 100,000-ton increase in imports during 2001 and a 300,000-ton decrease in exports.
The industry began to experience a slow turnaround during 2002. Decreased production in 2001 led to a tightening of supply during 2002. For example, OxyVinyls LP chloral-kali production facility in Deer Park, Texas, was idled during late 2001. The plant, which has an annual production capacity of 410,000 tons of chlorine and 451,000 tons of caustic soda, had supplied 3.0 to 3.5 percent of the country's chloral-kali market. Operating rates moved up from 85 percent in 2001 to approximately 90 percent in 2002.
Operating rates increased again in 2003, moving up to near 95 percent of capacity. Spikes in natural gas prices early in 2003 resulted in higher production prices for both caustic soda and chlorine. With production levels off 5 percent from 2002, supply continued to tighten, allowing for demand to push prices up. As a result, suppliers announced significant price increases in March 2003, the traditional season for contract renewals. Caustic soda prices increased as much as $125 per ton and chlorine by $70 per ton. U.S. demand for chlorine was predicted to rise by 2.5 percent annually through 2006, growing from 13.9 million tons to 15.7 million tons.
The U.S. Census Bureau reported that the chlorine and alkalies industry employed 4,693 workers in 2001 with a total payroll of $362 million. Of total employees, 3,256 worked in production. Louisiana, New York, and Washington led all states in producing chlorine, and Louisiana and Washington also produced 44 percent of American-made caustic soda. The average hourly wage for production workers in 2001 was $19.21.
Chlorine production in the United States accounts for almost 30 percent of the world's capacity, but there is little international movement of chlorine because of difficulties related to its transportation and storage. Producers generally prefer to erect production facilities in regions where demand exists.
In 1998 analysts predicted that worldwide chlorine demand would decline as the effects of the Asian economic crisis spread and slowed construction and use of PVC resins, amounting to nearly 40 percent of demand. By contrast, demand for caustic was strong in 1998, and producers struggled to put new facilities on line, increase production (at the Stade, Germany, plant operated by Dow Chemical, for example, where 120,000 metric tons of capacity were added in late 1998), and acquire the chlor-alkali facilities of other firms.
In 1996 soda ash had been predicted to grow in Asian exports from 130,000 metric tons to 140,000 tons in 1998; the economic catastrophe forced the industry to consider cutting back soda ash exports by as much as 100,000 metric tons in 1998 instead. Pulp and paper manufacturers and water treatment facilities were among those using soda ash as a caustic soda substitute; as the price of caustic soda rose in 1997 to $160 per ton, these industries switched back to soda ash, which helped balance Asian losses.
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