| 摘要 |
Liquor containing tar, oil and solids (1) flows through a downcomer (2) and a vertical cylindrical separator vessel (3) with a dished or conical base. Mean residence time is 20-45 minutes. The aqueous liquor, free from the tar phase, flows out through a side drain (5) above the downcomer discharge level. It enters a buffer vessel (6) at the same height, and continues under hydrostatic pressure to lower plant installations, for further purification and preparation. Tars, oils, solids and a small proportion of water, i.e. the tar phase, collect at the base of the separator vessel. Pumps (9) remove (8) the tar phase, returning it to various heights in the vessel or into the process water supply. To hold the tar phase depth constant in the vessel, some of the pumped flow is branched off to other plant for further uses. The tar phase is stirred (4) in the vessel to maintain its composition through suspension. After leaving the vessel base, additions are made to the tar phase, in accordance with its flow properties, composition and density. The additions comprise oil or a specially-prepared tar phase. The tar phase composition is optimized by oil- or specially prepared tar phase admixture, to reach 40-60 wt% tar/oil and 20-35 wt% solids. The additions are produced by the same plant. Tar phase is recycled from the base of the cylindrical vessel, directly back into the lower section, to the upper aqueous surface, or preferably to a mixing point in the process water supply, before entry into the downcomer. Tar phase is recycled from the base, to the individual feed points as required, or simultaneously. The pipework supplying process water the cylindrical vessel is constructed as a sectional static mixer, following the admixture point. Multiple parallel adjacent operation is feasible. Products are supplied for further recovery of valuable materials or for material uses.
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