Study On The New Environmental Friendly Process Of High Quality KCl Manufacture And Its Application

Potassium salt is an essential fertilizer for agriculture; meanwhile, it is widely used as an important raw material in chemical industry, metallurgical industry, electroplating, medicine, food industry etc. A great amount of potassium salt is demanded in the domestic market. However, the existing production capacity of potassium salt only accounts for fifteen percent of domestic market demand and about eighty percent relies on importing. Therefore, strengthening domestic potassium salt mining and usage, encouraging overseas partners to explore overseas potassium salt resources and set up potassic production base is an important way to solve domestic shortage of potassic fertilizer.The environmental problem caused by potassium salt mining is peculiar and different potassium salt storage type causes different environmental problems. For example, the main problems of salt lake potassium mining are water-salt balance keeping (which is critical to ensure sustainable natural resource exploiting), waste material storage (bittern, tail salt) and dressing medicament treatments and other possible environmental problems. The main environmental problems of underground solid potassium salt mining are ground surface changing, waste material storage and ecological problem etc.Based on the analysis of the environmental problems caused by traditional potassium salt mining, a new process, selective dissolution mining process and multi-element combined crystallizing technology to exploit underground solid potassium salt was presented in this paper, which can avoid and reduce the environmental problems.This process can selectively dissolve required substance, decrease the size of vacant mining cavity (it is about 1/2 of the mining cavity using dissolving process), and leave the un-required substance underground, with minimum possibility of ground sinking. Multi-element combined crystallizing technology together with the new process is adopted, without requiring to build large-scaled size salt field and it is a demonstration project withgood effects of environmental protection.When using traditional process, 8 tons of tail salt and 20 tons of bittern will be produced for one ton of KC1 product, while using this mining and manufacturing process, fewer wastes are produced, and the environmental effects caused by tail salt and bittern are avoided. Besides, the construction of salt field is not required.