SYSTEMS AND METHODS OF REMOVING TOXIC SUBSTANCES FROM WATER USING VERMIFILTRATION
Embodiments described herein are directed to methods and systems for treating wastewater or storm water using vermifiltration. The wastewater can come from various sources, such as agricultural sources, municipal and industrial sources, wineries, the dairy industry, and many others. The systems can include vermicomposting beds that are capable of removing high amounts of contaminants, pollutants, and/or toxic substances from wastewater. The wastewater may be applied to vermicomposting beds, for example, by an irrigation system. The irrigation system may provide, for example, improved bed coverage and more even saturation. The vermicomposting beds can remove various harmful substances from the wastewater, such as petroleum products; industrial chemicals; heavy metals (e.g., lead, mercury, cadmium, arsenic); pesticides (e.g., atrazine, chlorpyrifos); and organic compounds (e.g., phenols, polycyclic aromatic hydrocarbons (“PAHs”), polychlorinated biphenyls (“PCBs”)).
1 . A method of treating wastewater, the method comprising:
receiving wastewater;
pretreating wastewater in a pretreatment system, the pretreating comprising reducing an average particle size of solids in the wastewater;
vermifiltration of the pretreated wastewater in a vermifiltration system to produce a treated wastewater, the vermifiltration comprising flowing the pretreated wastewater through a vermifiltration bed; and
irrigating, using an irrigation system, the vermifiltration bed with pretreated wastewater,
wherein the irrigating comprises alternately flowing the pretreated wastewater and not flowing the pretreated wastewater, and
wherein the treated wastewater comprises fewer toxic substances than the wastewater.
2 . The method of claim 1 , further comprising controlling, by a control system, the irrigation system's schedule based on at least an amount of contaminants, pollutants, or toxic substances in the wastewater.
3 . The method of claim 1 , wherein the pretreating further comprises settling the wastewater in a settling tank to separate solids from the wastewater.
4 . The method of claim 1 , wherein the irrigating comprises flowing the wastewater for about 1 minute to about 5 minutes and not flowing the pretreated wastewater for about 30 minutes to about 60 minutes.
5 . The method of claim 1 , wherein pretreating comprises reducing the average particle size of solids in the wastewater to less than or equal to about 0.125 inches.
6 . The method of claim 1 , wherein the vermifiltration bed further comprises earthworms.
7 . The method of claim 1 , further comprising adjusting the pH of the pretreated wastewater.
8 . The method of claim 7 , wherein the pH is adjusted to about 7.
9 . The method of claim 1 , further comprising recirculating treated wastewater through to the vermifiltration system.
10 . The method of claim 1 , wherein the vermifiltration bed comprises a non-wood substrate.
11 . The method of claim 1 , wherein the treated wastewater has at least 75% fewer toxic substances than the wastewater.
12 . The method of claim 1 , wherein the treated wastewater has at least 90% fewer toxic substances than the wastewater.
13 . The method of claim 1 , wherein the treated wastewater has at least 95% fewer toxic substances than the wastewater.
14 . A method of treating wastewater, the method comprising:
receiving, from a wastewater source, wastewater, wherein the wastewater comprises at least one of municipal solid wastewater, industrial wastewater, winery wastewater, dairy wastewater, agricultural wastewater, roadway runoff, airport runoff, or storm water;
applying, by an irrigation system, wastewater to a vermifiltration system to produce a treated wastewater, wherein the vermifiltration system comprises a vermifiltration bed; and
controlling, by a control system, the wastewater application based on at least an amount of contaminants, pollutants, or toxic substances in the wastewater.
15 . The method of claim 14 , wherein the treated wastewater comprises fewer contaminants, pollutants, or toxic substances than the wastewater.
16 . The method of claim 14 , further comprising pretreating the wastewater to reduce an average particle size of solids in the wastewater.
17 . The method of claim 16 , wherein the pretreating the wastewater comprises pretreating in a wastewater pretreatment system.
18 . The method of claim 14 , further comprising discharging the treated wastewater.
19 . The method of claim 18 , wherein the discharging the treated wastewater comprises discharging the treated wastewater to surface water or groundwater.
20 . The method of claim 14 , further comprising recirculating the treated wastewater such that the irrigation system applies the treated wastewater to the vermifiltration system.