Sewage sludge dewatering - by mixing with mineral acid and adding ammonia to evaporate water by heat of reaction

摘要

The sewage sludge is mixed with a mineral acid or its anhydride to extract all water and to form a mixt. of sludge solids and diluted acid. The mixture is filled into a reactor with a base (ammonia) to produce enough heat of reaction to evaporate all water without any filtration, leaving a granulated product contg. the sludge solids and a salt. This system combines a rapid action with a high efficiency and low power consumption. It eliminates all environmental pollution problems and produces a fertiliser in a continuous process.