Treatment of storm water
View Patent ↗A treatment system for collecting storm water from an industrial area and removing suspended and dissolved pollutant materials from the storm water. Storm water is accumulated and delivered to a filtration apparatus in which suspended pollutants are removed by filtration, while dissolved materials, particularly heavy metals including zinc and copper, are removed by chemical chelation in a bed of compost filter media having a high humic acid content and which is kept consistently moist. A sparger provides for wide and generally uniform distribution of the storm water over the bed of filter media and provides for slow passage of the storm water through the filter bed, thus giving a long contact time of the storm water with the filter media in order to promote and enhance chemical chelation progress to chemical equilibrium and removal of a high percentage of dissolved metals, and particularly dissolved copper and zinc.
1. A storm water treatment system, comprising
(a) a filter and water treatment apparatus including:
(i) a treatment container having a length, a width, and a height;
(ii) a water filter and treatment media support platform within the treatment container including a water-pervious fabric bottom filter media containment layer;
(iii) a filter bed of particulate compost filter media within the support space, supported by the containment layer;
(iv) a cover layer of water-permeable fabric resting on the filter and treatment meshes;
(v) a sparger arranged to wet the top of the cover layer and distribute storm water over the filter bed; and
(vi) a filtrate collection space beneath the media support platform;
(b) a storm water collection and delivery system arranged to provide storm water to the sparger;
(c) a filtrate removal and discharge system; and
(d) a make-up water supply system arranged to provide water to the sparger as needed, to keep the filter bed continuously moist by distributing a quantity of water over the top of the filter bed through the sparger.
2. The storm water treatment of system of claim 1 wherein the treatment container has a filtrate-permeable bottom support member beneath the filter fabric bottom containment layer and defining a bottom of the media support platform.
3. The storm water treatment system of claim 1 wherein the compost filter media is a mixture of fine and coarse compost having a high initial humic acid content.
4. The storm water treatment system of claim 3 wherein the filter media is a compost of steer manure.
5. The storm water treatment system of claim 3 wherein the filter media is a compost of deciduous leaf material.
6. The storm water treatment system of claim 1 including a storm water-permeable containment member disposed over the cover layer of water-pervious fabric.
7. The storm water treatment system of claim 1 including a storm water feed tank mounted above the treatment container and arranged to deliver storm water to the sparger.
8. The storm water treatment system of claim 1 wherein the collection and delivery system includes an intermediate storm water collection container acting as a storage capacity buffer for accumulating a predetermined volume of storm water runoff during and following a storm event.
9. The storm water treatment system of claim 1 wherein the treatment container is a structure approximately the size of a commercial intermodal cargo container.