Phosphorus removal system and process
View Patent ↗A phosphorus removal system is operable to remove phosphorus from an influent. The system includes a first section receiving the influent and discharging a first flow. A first coagulant inlet is positioned upstream of the first section and is in fluid communication with the influent to introduce a first coagulant selected to precipitate phosphorus. A second section receives the first flow and discharges a second flow, and a third section receives the second flow and discharges an effluent. A second coagulant inlet is positioned downstream of the first section and upstream of the third section to introduce a second coagulant selected to precipitate phosphorus.
1. A phosphorus removal system for removing phosphorus from an influent, the system comprising:
a first section comprising a tube section, the first section receiving the influent, dividing the influent into a first flow and a sludge, and discharging the first flow;
a first coagulant inlet positioned upstream of the first section and in fluid communication with the influent to introduce a first coagulant selected to precipitate phosphorus;
a second section comprising an adsorption clarifier, the second section receiving the first flow and discharging a second flow;
a third section comprising a media filter, the third section receiving the second flow and discharging an effluent;
a second coagulant inlet positioned downstream of the first section and upstream of the third section to introduce a second coagulant selected to precipitate phosphorus;
a first return line connecting the sludge to a position upstream of, and in fluid communication with, the first section, wherein a portion of the sludge is pumped via the first return line to a position upstream of the first section, and wherein a portion of the sludge is mixed with the influent; and
at least one additional return line connecting a position downstream of the first section, to a position upstream of, and in fluid communication with, the first section, wherein a portion of contaminates from the position downstream of the first section is pumped via the additional return line to a position upstream of the first section, and wherein a portion of the contaminates is mixed with the influent,
wherein a third coagulant is introduced into the first return line before the portion of sludge is mixed with the influent.
2. The system of claim 1 , wherein the influent enters the first section below the tube section and the first flow exits the first section above the tube section.
3. The system of claim 1 , wherein the first coagulant and the second coagulant are at least one metal salt.
4. The system of claim 3 , wherein the at least one metal salt is chosen from alum, ferric chloride, and ferric sulfate.
5. The system of claim 1 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the first flow.
6. The system of claim 1 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the second flow.
7. The system of claim 1 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the media filter during a backwash cycle.
8. The system of claim 1 , wherein the tube section comprises inclined tubes.
9. The system of claim 1 , wherein the at least one additional return line is downstream of the second section.
10. The system of claim 1 , wherein the at least one additional return line is downstream of the third section.
11. The system of claim 1 , wherein the media filter is a mixed media filter.
12. A phosphorus removal system for removing phosphorus from an influent, the system comprising:
a first section comprising a tube section, the first section receiving the influent, dividing the influent into a first flow and a sludge, and discharging the first flow;
a first coagulant inlet positioned upstream of the first section and in fluid communication with the influent to introduce a first coagulant selected to precipitate phosphorus;
a second section comprising an adsorption clarifier, the second section receiving the first flow and discharging a second flow;
a third section comprising a media filter, the third section receiving the second flow and discharging an effluent;
a second coagulant inlet positioned downstream of the first section and upstream of the third section to introduce a second coagulant selected to precipitate phosphorus;
a first return line connecting the sludge to a position upstream of, and in fluid communication with, the first section, wherein a portion of the sludge is pumped via the first return line to a position upstream of the first section, and wherein a portion of the sludge is mixed with the influent; and
at least one additional return line connecting a position downstream of the first section, to a position upstream of, and in fluid communication with, the first section, wherein a portion of contaminates from the position downstream of the first section is pumped via the additional return line to a position upstream of the first section, and wherein a portion of the contaminates is mixed with the influent,
wherein a third coagulant inlet is positioned to introduce a third coagulant into the at least one additional return line, the third coagulant selected to precipitate phosphorus.
13. The system of claim 12 , wherein the influent enters the first section below the tube section and the first flow exits the first section above the tube section.
14. The system of claim 12 , wherein the first coagulant and the second coagulant are at least one metal salt.
15. The system of claim 14 , wherein the at least one metal salt is chosen from alum, ferric chloride, and ferric sulfate.
16. The system of claim 12 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the first flow.
17. The system of claim 12 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the second flow.
18. The system of claim 12 , wherein the second coagulant inlet is positioned to introduce the second coagulant to the media filter during a backwash cycle.
19. The system of claim 12 , wherein the tube section comprises inclined tubes.
20. The system of claim 12 , wherein the at least one additional return line is downstream of the second section.
21. The system of claim 12 , wherein the at least one additional return line is downstream of the third section.
22. The system of claim 12 , wherein the media filter is a mixed media filter.