Raw Coal Pyrolysis in Coal Chemical Industry

Client：A coking enterprise in Northwest China

Daily Treatment Capacity：850m³

Source of Treatment Solution：

Raw coal pyrolysis is a dry distillation process carried out under anoxic or oxygen-limited conditions, producing coal gas, tar, and semi-coke, along with a large volume of oily wastewater.
During pyrolysis, macromolecular organic compounds such as lignin and cellulose decompose to form various phenolic compounds.
In the tar condensation stage, part of the low-boiling-point phenols condense with steam and enter the pyrolysis water.
Meanwhile, nitrogen-containing organics decompose at high temperatures to form ammonia, which dissolves into the cooling water during gas scrubbing, generating ammonium salts.
As a result, a phenol–ammonia–oil-containing wastewater is produced.
This wastewater is characterized by large fluctuations in oil content, high suspended solids (SS), and variations in the ratio of heavy to light oil depending on the coal feedstock quality.
The previously used large-tank sedimentation process resulted in poor separation efficiency, frequent sludge accumulation, and unstable effluent quality.
By implementing the CASAIS Aggregation-Induced Separation process, these operational problems were effectively resolved.
The system provided stable, high-efficiency oil–water separation, reduced sludge generation, and significantly improved effluent clarity and consistency, enabling the plant to achieve reliable, continuous operation under varying coal and wastewater conditions.

Process Comparison

Treatment Effect