Environmental Investigations in Dry Cleaning Operations
Contaminant Source Areas – Where to Sample
Distillation Unit Although distillation units are built into the newer drycleaning machines, they are sometimes a separate piece of equipment in drycleaning facilities. 
A common operational problem with distillation units is overfilling (when too much spent solvent or muck is placed in the still/muck cooker) and subsequent boilover of distillation residues resulting in the discharge of still bottoms or cooked powder residues to the facility floor. Boilover can also be caused by excessive still operating temperatures. In early drycleaning operations, the distillation unit was often located in a separate room or even outside the facility in a covered area due to the strong odors generated during the distillation process. Former still locations can often be identified by brown colored staining on facility floors or walls.  
This staining is associated with either boilover of still bottoms or from splashing or spilling of still bottoms or cooked powder residues during still cleanout. The area around the still is a prime sampling location at drycleaning facilities. |
