sulfate by a double decomposition reaction. Although the black ash method produces a higher purity SrCO3 product, it is more energy intensive than the double decomposition process. Beside the two above commercial methods, there are several reports of the conversion of celestite to SrCO3 by other methods including the high temperature and high-pressure reaction between celestite and either sodium or potassium carbonate and direct leaching of celestite with Na2S to produce SrCO3.

Na2 CO3 +SrSO4 =Na2 SO4 +SrCO3

Strontium occurs commonly in nature, averaging 0.04% of the Earth’s crust, making it the 15th element in abundance (MacMillan and others, 1994). Only two minerals, celestite (strontium sulfate) and strontianite (strontium carbonate), however, contain strontium in sufficient quantities to make its recovery practical. Of the two, celestite occurs much more frequently in sedimentary deposits of sufficient size to make development of mining facilities attractive. The major use of strontium (as carbonate) is in color television picture tube faceplate glass. Other important uses are in ferrite ceramic magnets, pyrotechnics, and signals. Smaller uses include chemicals, electrolytic production of zinc, and pigments and fillers.

Hengyang Industry is an Chinese Company based in Zhengzhou city that manufactures, on proprietary technology, plants and equipment for waste recycling and recovery with energy production, material recovery or production of finished goods.

Innovation, R&D, passionate and skilled team along with the customer satisfaction have always been the success of Hengyang and they still are the peculiarities of our Company. Besides the historical Hengyang equipment, like single and double shafts shredders, Crushing machine, briquetting machines, separators, squeezers and centrifuges, the Company offers a wide range of turn-key plants, among which:

• briquetting and pelletizing plants
• shredding plants
• Waste Sorting Plants
• Bio-fuel Plants
• Waste to Power Recycling Plants
• Mining Plants
• OEM Equipments
……..
Hengyang is able to develop customized solutions too.
Designed, constructed and assembled by the same Hengyang

The Company policy focuses on product quality: robustness and functionality of the machines that maintain their value over time.
The ability to challenge ideas and concepts and to interact with partners worldwide has allowed and still allows Hengyang to stay highly competitive and to be an ideal partner for the world market.