Method for producing fertilizers and bases from sludges

Claim 1

A PROCESS OF MANUFACTURING A MIXED PHOSPHATIC FERTILIZER WHICH ALSO CONTAINS NITROGEN, POTASH AND MAGNESIUM AND IS LOW IN CHLORINE WHICH COMPRISES PASSING GAS FROM THE DESTRUCTIVE DISTILLATION OF COAL THROUGH A BATH OF SULPHURIC ACID, THE RATIO OF SAID SULPHURIC ACID TO THE AMMONIA OF THE GAS BEING SUCH AS TO PRODUCE A FIRST ACIDIC SLUDGE, MIXING POTASSIUM CHLORIDE AND SULPHURIC ACID IN PROPORTIONS TO EVOLVE HYDROGEN CHLORIDE AND TO FORM A SECOND ACIDIC SLUDGE, THE AMOUNT OF SULPHURIC ACID BEING SUBSTANTIALLY GREATER THAN THAT WHICH IS NECESSARY TO PRODUCE THE AMOUNT OF HYDROGEN CHLORIDE WHICH IS EVOLVED, MIXING SAID FIRST AND SECOND ACIDIC SLUDGES GROUND PHOSPHATE ROCK AND GROUND DOLOMITE IN PROPORTIONS TO CONVERT THE INSOLUBLE MAGNESIUM OF THE LIMESTONE TO A SOLUBLE FORM AND THE UNAVAILABLE PHOSPHATE OF THE ROCK TO AVAILABLE FORMS, THE CONCENTRATION OF SAID ACID BEING SUCH AS TO SUPPLY NOT MORE THAN THE AMOUNT OF WATER REQUIRED IN THE ACIDULATION REACTION AND THE AMOUNT NECESSARY TO FURNISH SUBSTANTIALLY THE FULL AMOUNT OF WATER OF CRYSTALLIZATION FOR THE COMPLETELY HYDRATED PRODUCT AND THE ABOVE OPERATIONS BEING CARRIED OUT IN THE ABSENCE OF EXTERNAL HEAT, AND CURING SAID MIXTURE.