# US 2014/0190897 A1 · Enhanced separation of nuisance materials from wastewater > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190897 A1 - Document ID: US20140190897A1 - Status: Published application - Kind: A1 - Application number: 14/206,740 - Filed: 2014-03-12 - Published: 2014-07-10 - Earliest claimed: 2011-09-12 - Inventors: George E. Wilson - Web page: https://patentgrep.com/patent/US20140190897A1 ## CPC - C02F 1/24: by flotation (C02F1/465 takes precedence) - B01D 21/0045: {Plurality of essentially parallel plates} - B01D 21/0084: {Enhancing liquid-particle separation using the flotation principle (flotation in general B03D1/00)} - B01D 21/01: using flocculating agents (for purifying water C02F1/52; for liquid radioactive waste G21F9/10) - B01D 21/2411: {having a tangential inlet} - B01D 21/2427: {The feed or discharge opening located at a distant position from the side walls} - B03D 1/24: Pneumatic {(mixing gases or vapours with liquids B01F23/20)} - C02F 2001/007: {Processes including a sedimentation step} - C02F 2101/32: Hydrocarbons, e.g. oil - C02F 2305/04: Surfactants, used as part of a formulation or alone - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B03D: FLOTATION; DIFFERENTIAL SEDIMENTATION (sedimentation in general B01D21/00; in combination with other separation of solids B03B; sink-float separation B03B5/28; detergents, soaps C11D) ## Abstract According to one implementation, a method of treating wastewater includes introducing air bubbles having a predetermined size into raw influent, allowing the air bubbles time to bind with grease particles in the influent and to rise, and collecting the grease particles bound with the air bubbles on an upper surface of the influent. ## Claims ### Claim 1 A method of treating wastewater, comprising: introducing air bubbles having a predetermined size into raw influent; allowing the air bubbles time to bind with grease particles in the influent and to rise; and collecting the grease particles bound with air bubbles on an open upper surface of the influent. ### Claim 2 (depends on 1) The method of claim 1, further comprising collecting garbage that has floated to the top of the open upper surface. ### Claim 3 (depends on 1) The method of claim 1, further comprising conveying degreased influent to a grit removal stage. ### Claim 4 (depends on 1) The method of claim 1, wherein introducing air bubbles having a predetermined size into the raw influent includes using an injector with a water-surfactant motive flow to entrain air and injecting the resulting water-surfactant-air mixture into the raw influent. ### Claim 5 (depends on 1) The method of claim 1, wherein introducing air bubbles includes injecting air bubbles with an array of injectors. ### Claim 6 (depends on 1) The method of claim 1, further comprising causing gravel in the influent to settle as the air bubbles are rising. ### Claim 7 (depends on 1) The method of claim 1, wherein collecting the grease particles bound with the bubbles includes skimming an upper surface of the influent to remove the grease. ### Claim 8 (depends on 1) The method of claim 1, wherein collecting the grease particles bound with bubbles includes skimming an upper surface of the influent with an air stream to remove the grease. ### Claim 9 (depends on 8) The method of claim 8, further comprising dewatering the removed grease and adding liquid removed from the grease to the raw influent for recycling. ### Claim 10 (depends on 1) The method of claim 1, further comprising urging at least removed grease up a ramp positioned adjacent the upper surface of the influent and concurrently dewatering the removed grease. ### Claim 11 A removal stage configured to remove at least one nuisance material from wastewater, comprising: a tank sized to receive an inflow of influent; at least one injector positioned at a bottom of the tank to inject a mixture of liquid and air in the form of air bubbles having a predetermined size into influent received in the tank, the air bubbles being configured to bind with at least grease particles in the influent and rise through the tank; a skimming device positioned to skim the grease particles bound with air bubbles from a top surface of the tank. ### Claim 12 (depends on 11) The removal stage of claim 11, wherein the at least one injector comprises an array of at least eight injectors arranged about a central axis of the tank. ### Claim 13 (depends on 11) The removal stage of claim 11, wherein the skimming device comprises a nozzle positioned to direct an air stream onto the top surface of the tank and to move accumulated grease to an opposite side. ### Claim 14 (depends on 11) The removal stage of claim 11, further comprising a supply of surfactant for providing surfactant in the mixture of liquid and air, the surfactant tending to keep the predetermined size of the bubbles small. ### Claim 15 (depends on 11) The grease removal stage of claim 11, wherein in operation there is a filter of dispersed air bubbles rising through the influent that produces a local region of lower density permitting faster settling of gravel in the influent. ### Claim 16 (depends on 11) The removal stage of claim 11, further comprising at least one outlet and a grit removal stage connected to the outlet. ### Claim 17 (depends on 16) The removal stage of claim 16, wherein the removal stage and the grit removal stage are positioned together in the tank. ### Claim 18 (depends on 16) The removal stage of claim 16, wherein the outlet comprises multiple, vertically spaced outlets sized and shaped to have equal flow and to connect to a hydraulic grit separation stage. ### Claim 19 (depends on 16) The removal stage of claim 16, further comprising a gravel collection region at the bottom of the tank for storing gravel that has settled from the influent. ### Claim 20 (depends on 16) The removal stage of claim 16, wherein the skimming device is configured to collect garbage from the influent that floated to the surface of the tank.