The Hongze Lake is located in Jiangsu Province of China.

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Abstract

China is the largest producer and exporter of sodium sulfate. Jiangsu Province is the world’s largest sodium sulfate production base, with a total capacity of 800 thousand metric tons. In 2003, Lautan Hongze Chemical Industry began commercial production at the world’s largest sodium sulfate plant in Hongze County. China’s production, consumption, and exports of sodium sulfate have been increasing significantly in the past few years.
Sodium sulfate is consumed in four major industries—kraft pulping, detergents, textiles and glass. In the United States, consumption in each of these end uses has declined. The largest overall decline has been in kraft pulping for the pulp and paper industry, mainly as a result of the introduction of the hydrogen peroxide and sodium chlorate processes. Decreases in the U.S. market, especially in the textile sector, have also been a direct result of the industry’s shift to Mexico. The major end use for sodium sulfate in Canada was formerly kraft pulping. This end use accounted for over 90% of total sodium sulfate consumption in Canada until 1972. Since then, consumption for kraft pulping has declined drastically due primarily to antipollution regulations. In Western Europe, sodium sulfate is consumed in four major industries—detergents, glass, kraft pulping and textiles. Detergents are the foremost consumers of sodium sulfate, accounting for over 80% of total consumption. In Japan, textiles, detergents, bath additives and glass account for 80% of consumption, with textile uses accounting for over 30%.
In North America, the recent closure of several plants has helped to eliminate the oversupply situation the sodium sulfate market has faced in the past few years. The largest contraction happened in January 2001 when Saskatchewan Minerals closed its Ingebrigt plant in Canada indefinitely. DLD Resources in Monument, New Mexico and Acordis in La Moyne, Alabama also recently shut down their operations. Balanced supply resulted in price increases for customers. Demand is expected to remain stable or to grow slightly in the near future as exports to Central and South America increase to satisfy the expanding textile sector. Consumers overall accepted the price increases introduced in 2001 and 2005. In October 2004, Cooper Natural Resources and Giles Chemical combined to form Saltex, which has become one of the two major marketers of by-product sodium sulfate in North America.
Mexico has been an increasing market for sodium sulfate lately as a result of demand from its detergent and textile sectors. Along with production, exports to South America have also grown steadily in recent years.
A factor that has an impact on sodium sulfate supply is the chromium business of UK-based Elementis. It cut its chromium production significantly and as a consequence, sodium sulfate generation was also reduced. Similarly, DSM decided to stop producing ascorbic acid at its Belvidere plant in 2005, thereby reducing by-product sodium sulfate supply. In late 2005, Liberty Fibers also closed down its Tennessee plant, citing competitive pressures.
There are sufficient resources of sodium sulfate to last for a long time. Major countries that have reserves include the United States, Spain, Mexico, Turkey, China and Canada. In the United States, the brine in Searles Lake, California and western Texas are used for commercial production. Both these locations are estimated to have a combined 860 million metric tons of reserves. In June 2005, Vancouver-based Atacama Minerals initiated activities to start producing sodium sulfate from its Aguas Blancas iodine-sulfate-nitrate mine in Chile. It is estimated to have around 4–5 million metric tons in reserve.