Specification of Burton Henry Vallé : treating sewage.

  • Vallé, Burton Henry.
Date:
1875
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Burton Henry Vallé : treating sewage. Source: Wellcome Collection.

    10/22 (page 8)
    Valle's Improvements in Treating Sewage, horizontal layer of gravel, the whole being placed between upper and lower filtering floors c, c\ constructed of oak with cast and wrought-iron girders, and provided with apertures c2 for the passage of the liquid sewage, the upper floor c being made double with friction rollers between to enable the upper half of the floor to slide longitudinally upon the 5 lower half, for the purpose of making their apertures coincide or not as required. This movement is effected by means of a gearing chain wheel and capstan. The thickness of filters B1 and the depth of filtering beds C, and the number of filtering compartments A depends upon the quality of the sewage to be filtered, and must be determined by the 10 result of analysis of the effluent water at the outfall channel. In order to remove the sludge remaining in the tanks A after filtration of the sewage the upper floor c is constructed to be raised at one side (the apertures c2 having been previously closed) so as to cause the sludge to flow through sluices d and spouts dl into a receptacle or bed Gr, outside 15 the tanks, wherein it may be allowed to remain exposed for a short time to the action of the atmosphere until sufficiently dry for conveyance where required. The raising of the upper floor of the filtering beds may be effected by means of chains attached to hooks bolted to the lower half of floor <?, 20 and passing through slots in the upper half to admit of the sliding move¬ ment before mentioned. The chains from either end pass over guide pulleys to two independent shafts, as shown in Pigure 3. This arrange¬ ment admits of the floor being raised at the end furthest from the sluices d by revolving one of the shafts, and also, as occasion may 25 require, of being raised at both ends by the simultaneous revolution of the two shafts sufficiently for the purpose of renewing the filtering bed. The sluices d are opened and closed by means of a rack and pinion. The sewage, which it is preferred should be kept separate from the rainfall drainage, is first received from the sewer in a tank P, which 30 may be termed an intercepting or settling tank, whence the sewage is conveyed by a conduit P1 to the one or other series of filtering tanks A, the flow of the sewage being controlled by valves or sluices e. The flooi of the intercepting tank P has a downward slope from one side of the tank to the other, where two pumps / are placed for emptying the 35 intercepting tank P when required, the one serving to pump the fluid part of the sewage into the conduit P1, and the other to raise the sludge deposited