| 摘要 |
<p>502,530. Filters. DEKEMA, C. J. Sept. 13, 1938, No. 26680. Convention date, July 30. [Class 46] Sewage or other biologically impure liquid percolates downward in succession through each of two or more enclosed filters, the media in which are aerated by forcing therethrough a regulated volume of oxygen-containing gas under controlled pressure. Means are provided for separating air and solids from the effluent from each filter before it is passed to the next and for changing the order of sequence for liquid flow through the series. With the apparatus shown, liquid supplied through a pipe 12 to sprinkers 8 passes downward through a filter 1, is collected in a drain 3 and passed through an air trap 6 to a sediment tank 30. It is elevated thence by a pump 36 to sprinklers 9 for distribution over a similar filter 2. Alternatively, liquid supplied first to the filter 2 through a pipe 13 may be passed on through the filter 1. The filters are provided with blowers 18, 19 for the supply of air and with pipes 24, 25 through which air is drawn off at the top. The pipe 24 may be connected to the blower 19, so that the air which has passed upward through the filter 1 may be supplied to the filter 2 and pass upward therethrough. Alternatively, air which as passed upward through the filter 1 may pass through a connection 42 at the top and then pass downwardly through the filter 2. Modified apparatus is shown in which the blowers are connected to the tops of the filters and there is an air passage connecting the filters at the lower end. The filters may be kept at the best temperature for the biological treatment either by previously heating the liquid or by supplying hot air and by means of heating-coils embedded in the filters or arranged above them. Disinfectants, deodorants, insecticides or treating agents, for example ozone or chlorine, may be introduced into the gas used for aerating the filters.</p> |
