Abstract:
A device for collecting, temporarily storing and draining off rainwater comprises an intermediate storage tank (2), which is provided with at least one infeed (4), a first outlet (8) arranged close to the bottom (6) of the tank and a second outlet (10) arranged at a distance above the bottom. The first outlet (8) is provided with a self-adjusting flow limiter (20), preferably in the form of a valve which is controlled by the flow rate into the first outlet (8) and has a ball-shaped valve body (24) which is able to close off the inflow opening (18) of the first outlet (8). The relative density of the ball (24) is slightly greater than that of water. In the event of light rainfall, contaminated rainwater is drained off via the first outlet (8), while in the event of heavy rainfall the first outlet is closed off by the ball (24) and relatively clean rainwater is drained off via the second outlet (10).
Abstract:
A grate (111)-covered gutter (110) of a paved part of the earth's surface (100) is temporarily closed off by means of a closing organ (130), the gutter (110) being connected to a sewage pipe (120). Thus, the draining away of contaminating liquid can be prevented. The closing organ (130) includes a valve (131 fitted rotatably in the gutter (110). The valve (131) can be in a first stable position wherein the valve (131) seals. The valve can also be in a second stable position in which the valve (131) releases the gutter (110) for the discharge of liquid (rainwater) to the sewage pipe.
Abstract:
A system for purifying rainfall runoff including a bar screen; a collection and diversion device; a filter channel; a grass ditch; and a water storage tank. The bar screen is disposed around the collection and diversion device for preliminarily filtering the road rainfall runoff. The collection and diversion device collects the road rainfall runoff and diverts early rainfall runoff to the filter channel, after the filter channel is full, later rainfall runoff is directly diverted to the grass ditch through open channels. The grass ditch includes a percolation bed capable of filtering the early and later rainfall runoff. The water storage tank is connected to the grass ditch via a guiding pipe, to receive the rainfall runoff effusing out of the grass ditch. Part of the rainfall runoff received by the water storage is transported to the percolation bed by a return conduit.
Abstract:
Three flow paths within a single container are provided for the separation of contaminates, such as floating debris, heavy trash, lighter fluids and heavier fluids, from an effluent stream. A first flow path is provided for low flow conditions wherein the effluent stream pools in a first chamber within the container and the surface of the pooled fluid is drawn off, leaving heavy contaminates within the first chamber. The drawn fluid, with lighter and/or floating contaminates, enters a second chamber. The fluid is drawn from the second chamber below the surface level of the fluid, leaving the lighter and floating contaminates within the second chamber. In moderate flow conditions, a second flow path is established from the first chamber and out the container, bypassing the second chamber. Fluid for the second flow path is drawn from below the surface of the fluid in the first chamber to exclude light and floating contaminates. A third flow path is established when the first and second flow paths are insufficient to accommodate the effluent received by the container. The third flow path draws from the surface of the fluid in the first chamber and bypasses the second chamber in discharging from the container.
Abstract:
Systems and methods for treating water passing through a catch basin may include first and second filters. In some embodiments, one or both of the filters can have a plurality of regions with different nominal flow rates.
Abstract:
A passive flow control valve including a barrier member adapted to attach to a fluid conduit. The barrier member defining an upper portion, a lower portion and an intermediate portion depending from the upper portion and the lower portion. The lower portion and the upper portion each defining an opening therein for allowing fluid to pass therethrough. The intermediate portion defining at least one orifice defined therein, wherein the orifice is configured to allow substantially controlled fluid flow therethrough. The flow control valve may also include a passive arrangement for collecting floatables discharged from a pipe.
Abstract:
A drainwater treatment system positionable within a horizontal flow passage of a drainage system utilizes a partition which divides the flow passage into an upstream chamber and a downstream chamber. In addition, a mid-panel is supported within the upstream chamber for dividing the interior of the upstream chamber into an upper section and a lower section so that the drainwater enters the upper section before entering the lower section through a first opening provided in the mid-panel. A conduit is also joined between a second opening provided in the mid-panel and the opening of the partition for conducting drainwater from the lower section of the upstream chamber to the downstream chamber so that the drainwater which enters the upper section and then into the lower section is decelerated to flow conditions at which debris and suspended are permitted to separate and settle from the drainwater before being conducted from the lower section and into the downstream chamber through the conduit. Furthermore, a series of filters are supported within the downstream chamber so that drainwater which flows into the downstream chamber from the upstream chamber flows in sequence through the series of filters before exiting the downstream chamber.
Abstract:
A method and apparatus for treating contaminated stormwater runoff from roads and adjacent lands. A multi-stage and self-contained system designed to collect the "first flush" of stormwater runoff (which contains the majority of pollutants) and to treat the pollutants using sedimentation, filtration and constructed wetlands. The apparatus is mass-produced to provide standardized hydrologic controls, important to the reliability of the constructed wetland component of the apparatus.Raw stormwater enters the central sedimentation chamber of the apparatus which is divided into multiple segments designed to provide a series of sedimentation/filtration chambers. Each chamber is divided by a removable filter bulkhead sequenced from coarse to fine sediment sizes. Effluent from the final sedimentation chamber is discharged to the constructed wetland system which surrounds the central sedimentation basin. Water flows through the perimeter wetland system in subsurface/saturated conditions and contacts the root zone of the constructed wetland where biochemical interactions attenuate pollutants.Hydrologic control valves in the apparatus regulate the flow of water from the sedimentation basin to the wetland and the effluent discharge rate out of the wetland. This control and the standardization of the construction allows for precise hydrologic controls designed to provide a 5-10 day holding time within the apparatus.
Abstract:
A device for collecting, temporarily storing and draining off rainwater comprises an intermediate storage tank (2), which is provided with at least one infeed (4), a first outlet (8) arranged close to the bottom (6) of the tank and a second outlet (10) arranged at a distance above the bottom. The first outlet (8) is provided with a self-adjusting flow limiter (20), preferably in the form of a valve which is controlled by the flow rate into the first outlet (8) and has a ball-shaped valve body (24) which is able to close off the inflow opening (18) of the first outlet (8). The relative density of the ball (24) is slightly greater than that of water. In the event of light rainfall, contaminated rainwater is drained off via the first outlet (8), while in the event of heavy rainfall the first outlet is closed off by the ball (24) and relatively clean rainwater is drained off via the second outlet (10).