Patent GB-190007834-A (GB)
Title: Improvements in Automatic Apparatus for Regulating the Working of Filters for the Treatment of Sewage and other Liquids.
Inventor: CAMERON DONALD
Filed: 1900-04-27
Granted: 1901-04-27
Abstract: 7834. Cameron, D., Commin, F. J., and Martin, A. J. April 27. Filters, supplying and discharging liquid in.-Relates to apparatus for regulating the working of filters, or bacteria beds, for treating sewage and other liquids. Fig. 3 shows in section a regulating-apparatus for one filter. The sewage &c. flows from a storage tank 11. into a chamber 6, provided with a valve 4, for controlling the flow to the filter bed 7. The sewage &c. is discharged from the filter bed into a chamber 9, provided with a discharge valve 1. The valves are preferably made with looped stalks for engaging with pins at the lower ends of two rods 5, 2, which respectively carry floats 10, 12 and are connected to arms fixed to a rocking shaft 13. When two filters are employed, the inlet valves for both filters may be suspended from one lever in the way described in Specification No. 19,697, A.D. 1898; when the lever is horizontal, both valves will be closed. The lever is locked in its horizontal position by a catch carried by a lever which is actuated by means of a separate float or other means. The buckets or floats, for actuating the discharge valves, may be carried by the discharge-valve rods, as described in Specification No. 5671, A.D. 1898, or they may be suspended independently. as described in that Specification. The floats may be suspended from the same lever as the discharge valves, but in chambers separated from the discharge wells by partitions having their upper edges at the level to which the filters are to be filled. When buckets are employed, a weight may be placed on the lever, as described in Specification No. 27,349, A.D. 1897. When four filter beds are employed, the controlling-apparatus may be arranged as shown in Fig. 7, the filters being arranged in pairs. The overflow pipe 21<a>, 21<b>, or 21<c>, from any filter bed of a pair, is connected with one of the float chambers of the other pair. The controlling- apparatus is of the kind described in Specification No. 3003, A.D. 1896. All four inlet valves 4, 4<a> are arranged within a valve chamber 6, supported by four discharge wells 3, 3<a>. Four bucket or float chambers 19, 19<a> are bolted to the wells, and within them are floats or buckets 17, 17<a>, carried by levers 18, each of which also supports two inlet valves 4. 4<a> and two discharge valves 1, 1<a>. The buckets, when used, may be emptied after an operation of the valves, or may remain full as stated in Specification No. 5671, A.D. 1898. The upper ends of the rods 5, 5<a>, 2, 2a, connecting the valves to the levers 18, may be looped. When starting the controlling-apparatus it is necessary to hold one of the levers 18 in an inclined position, until one of the filters has been charged ; this retention is effected by means of a pivoted weight 23, which can be turned so as to rest on one end of one of the levers 18. More than four filter beds may be connected in series, and their overflow pipes may be provided with cocks, to allow any pair of filters to be put out of action, as described in Specification No. 3003, A.D. 1896. In another arrangement, comprising several groups of filters, an alternating apparatus of the kind described in Specification No. 18,322, A.D. 1899, is preferably employed, the discharge of each filter bed being caused by an overflow of effluent into its actuating-bucket, and the opening of the inlet valve being effected by the discharge of effluent from the bucket when another filter is emptied. The sewage &c. is caused to accumulate in the storage tanks while a filter remains charged, but, instead of regulating this accumulation by means of a regulating-orifice on the overflow pipe, as described in Specifications No. 5671, A.D. 1898, and No. 22,965, A.D. 1897, the overflow is allowed to pass freely into the bucket until it descends, and effects the closing of the inlet valve. The overflow is then stopped automatically by means of a valve fitted to the overflow pipe. When a sewage plant comprises two or more independent groups of filter beds, two or more inlet valves may be open at the same time, resulting in a correspondinglyslower filling of the filters. To prevent this, flow may be concentrated by means of the apparatus represented in Fig. 10. The flow to each group of beds is regulated by a corresponding valve 32 or 32<a>, fitted in a sewage passage 33 and actuated, if desired, by means of floats 34, 34<a>, so that only one valve can be open at a time. The floats 34, 34<a> respectively float in chambers 35, 35<a> provided with discharge pipes fitted with valves 37, 37<a>. When one float 34 or 34<a>, belonging to one group of filter beds, ascends, the valve 37<a> or 37 is raised to allow the sewage &c. to be discharged from the chamber 35<a> or 35, belonging to the other group. The valves 32, 32<a> may be actuated by tipping-buckets, in the way described in Specification No. 23,042, A.D. 1896. In order to allow the time during which a filter bed remains charged to be properly regulated, the supply of fluid for filling the valve-actuating buckets, of a series of filter beds, may be conducted past a ball valve 38, Fig. 12, into a cistern 39 provided with a series of valves 40, 40<a>, 40<b>, 40<c>, connected to a lever 17, which carries a float 45 in the sewage-supply channel 6. The valves 40, 40<a>, 40<b>, 40<c> control the flow of sewage into the buckets 25, into which the liquid runs from pipes 42, fitted with valves 43, which are controlled by means of floats 44 in the discharge wells 3. When the flow of sewage in the channel 6 is great, the float 45 is lifted, and several of the valves 40, 40<a>, 40<b>, 40<c> are opened, thus allowing the buckets to be rapidly filled. A single long conical valve may be employed instead of a series of valves 40, 40<a>, 40<b>, 40<c>, the valve passage being varied according to the extent to which the valve is raised. The pipes 42 may be connected to a central office or laboratory, whence the flow of liquid to the buckets may be regulated by hand. Instead of determining the time during which a filter remains charged, by varying the number of orifices 40, 40<a>, 40<b>, 40<c> in use, the desired regulation may be effected by varying the head of liquid above such orifices. When a large flow of sewage &c. is being dealt with, the filters are filled and emptied in rapid succession, but automatically-actuated means is provided to prevent any filter from being brought into action too soon after its previous filling, and the number of filters in use may be automatically increased or reduced for the purpose of dealing with varying quantities of sewage. In place of the air valve described in Specification No. 5671, A.D. 1898, attached to the siphon for discharging a valve-actuating bucket, a vent pipe in the form of a siphon may be employed.