GB462094A - Improvements relating to the treatment of sewage and like sludge and apparatus therefor - Google Patents

Abstract

462,094. Treating sewage. TRIGGS, W. W. (Dorr Co., Inc.) May 27, 1936, No. 14952. [Class 111] [Also in Group XXX] Apparatus for treating sewage and like sludge comprises means for adding reagent to the sludge, a mixing chamber 15, a rotary vacuum or other filter 52 for de-watering the sludge and a bucket elevator 36 for raising the sludge from the mixing chamber to the trough 51 of the filter, all these parts being supported on a framework comprising horizontal and vertical beams 11, 13, and a cover 14 for the mixing-chamber. The mixing-chamber is divided into communicating sections 19, 20 by a partition 21 and the sludge is supplied to the section 19 which has vertical baffles 22 by a pipe 30. Reagents such as milk of lime and ferric chloride are supplied through pipes 28, 29 respectively and are thoroughly agitated with the sludge by air admitted through perforated or porous tubes 26, 27. The sludge and reagents are supplied to the mixing- chamber by pumps driven intermittently by electric motors, the current to which is controlled by a float in a chamber connected to the section 20, the float closing or opening a switch when the liquid level reaches a higher or lower limit respectively. The pump for the sludge is of such capacity that while the pump is operating the sludge will be supplied at a greater rate than it could be disposed of by the apparatus. The buckets 42, Fig. 3, of the elevator, which dips into a sump in the section 20, have a filling opening 47 at the front, one end being completely closed and the other open at the top 46 so that, when overturned at the top of their travel, the buckets deliver the sludge sideways into a hopper 48 connected with the filter trough 51 by a pipe 50. An openended pipe 53 is pivotally mounted in the side of the hopper 48 so that it serves as an overflow control to regulate the liquid level in the filter trough. A motor 71 drives pumps 67, 69 for drawing air and liquid respectively from the filter, and also a compressor 72 which supplies air to the tubes 26, 27 and for blowing-back through the filter. Another motor rotates the filter and drives the elevator.