Guar gum Ganganagar and Hanumangarh in Rajasthan are the major Guar trading markets. The United States has produced 4,600 to 14,000 tonnes of guar over the last 5 years. Texas acreage since 1999 has fluctuated from about 7,000 to 50,000 acres. The world production for guar gum and its derivatives is about 1.0 Million tonnes. Non-food guar gum accounts for about 40% of the total demand. Mainly it is used as a proppant transport / proppant suspending agent in hydraulic fracturing. At its peak the price was $8000 per ton. Chemically, guar gum is an exo-polysaccharide composed of the sugars galactose and
Hydrochloric acid regeneration on pyrohydrolysis and adiabatic absorption of hydrogen chloride in water, a process invented in the 1960s. However tightening environmental standards and stringent air permit policies render it increasingly difficult to establish new pyrohydrolysis-based acid regeneration plants. The following processes for the regeneration of HCl from spent pickle liquors have been adopted by the ferrous metals processing industry: Hydrothermal hydrolysis of hydrochloric SPL from carbon-steel pickling lines is a hydrometallurgical reaction, which takes place according to the following chemical formulae: 12 FeCl + 3 O → 8 FeCl + 2 FeO 2 FeCl + 3 HO → 6 HCl + FeO