摘要 |
A method and apparatus for purifying separate waste water from a dry cleaning process. The present invention utilizes 3 stages of purification. In Stage one, highly contaminated separator waste water (12) is put into a solvent separator tank (14). Liquid solvent (18) settles out of the separator waste water (12), sinking to the bottom of the solvent separation tank (14) where it accumulates below the separated water (20). In Stage 2 air bubbles are introduced through the separated water (20), stripping out much of the solvent which is dissolved in the separated water (20) and reducing the dissolved solvent concentration. This air stripping process dramatically extends the useful life of the granulated carbon in the granulated carbon filter (44), which results in the carbon purified water (46) having a dissolved solvent of less than 0.7 parts per million. The carbon purified water (46) can then be safely and economically disposed of without harming the environment.
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