Tachohydrite processing - with bischofite recovery

摘要

Bischofite recovery from natural tachohydrite by salting out subterranean deposits is effected by introducing water, at temps. up to 35 degrees C, through a bore-hole into the deposit where it remains until the bischofite satn. point has just been reached; then leading the soln. which is almost satd. with bischofite, carnallite and NaCl above-ground through another bore-hole and treating this soln. with synthetic tachohydrite (A), esp. at 35 degrees C. A decompsn. soln. satd. in bischofite, tachohydrite, carnallite and NaCl is formed with formation of decompsn. bischofite which is removed. The decompsn. soln. is evapd. until, on cooling, esp. to 35 degrees C, satn. in tachohydrite, CaCl2.4H2O and NaCl is reached under formation of synthetic tachohydrite which is introduced to step (A) and the resulting final soln. is ejected.