WO2008030234A1 - Procédé de récupération de nutriments - Google Patents

Procédé de récupération de nutriments Download PDF

Info

Publication number
WO2008030234A1
WO2008030234A1 PCT/US2006/034683 US2006034683W WO2008030234A1 WO 2008030234 A1 WO2008030234 A1 WO 2008030234A1 US 2006034683 W US2006034683 W US 2006034683W WO 2008030234 A1 WO2008030234 A1 WO 2008030234A1
Authority
WO
WIPO (PCT)
Prior art keywords
ammonia
stream
solids
gas
lime
Prior art date
Application number
PCT/US2006/034683
Other languages
English (en)
Inventor
Alexander G. Fassbender
Original Assignee
Fassbender Alexander G
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fassbender Alexander G filed Critical Fassbender Alexander G
Priority to PCT/US2006/034683 priority Critical patent/WO2008030234A1/fr
Publication of WO2008030234A1 publication Critical patent/WO2008030234A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
    • C02F5/02—Softening water by precipitation of the hardness
    • C02F5/06—Softening water by precipitation of the hardness using calcium compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/20—Treatment of water, waste water, or sewage by degassing, i.e. liberation of dissolved gases
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/74—Treatment of water, waste water, or sewage by oxidation with air
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/105—Phosphorus compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/16—Nitrogen compounds, e.g. ammonia
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/20—Nature of the water, waste water, sewage or sludge to be treated from animal husbandry
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/24—Separation of coarse particles, e.g. by using sieves or screens
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/28—Anaerobic digestion processes
    • C02F3/286—Anaerobic digestion processes including two or more steps

Definitions

  • Embodiments generally relate to a nutrient recovery process. More particularly, embodiments relate to a process for recovering ammonia from waste streams.
  • Waste streams contain several components which it is desirable to separate from the waste streams and from one another, either for recovery of the components for later use or to prevent release of the components or combinations of the components to the environment.
  • These waste streams may result from anaerobic digestion of sewage or animal wastes, from industrial processes such as rendering operations, and from coke and chemical manufacture.
  • Anaerobically digested sewage sludge and animal wastes may be separated into a solids-rich stream and a solids-depleted stream, where the solids-depleted stream contains the bulk of the water as well as a variety of chemicals dissolved and suspended in the water.
  • the suspended chemicals in the solids- depleted stream typically include ammonia nitrogen (NH 3 -N) having a typical concentration ranging from 800 parts per million (ppm) to 8,000 ppm, hardness in the form of calcium carbonate with a typical concentration ranging from 50 ppm to 350 ppm, phosphate having a typical range of concentration from 2 ppm to 150 ppm, and total suspended solids having a typical concentration range of 500 ppm to 2,000 ppm.
  • NH 3 -N ammonia nitrogen
  • ppm parts per million
  • phosphate having a typical range of concentration from 2 ppm to 150 ppm
  • total suspended solids having a typical concentration range of 500 ppm to 2,000 ppm.
  • Alkali earth salts dissolved in the solids-depleted stream are sometimes removed by cation exchange.
  • Cation exchange treatment outputs a spent brine stream which typically contains a high quantity of sodium.
  • the discharge of high quantities of sodium can be disadvantageous, especially in applications where the water will be discharged into fresh water or applied to soils.
  • an effective and efficient nutrient recovery process which is acceptable in either fresh water applications or salt water applications, or where water is applied to soils or otherwise released to the environment.
  • This nutrient recovery process involves mixing the waste water with lime to precipitate calcium carbonate, which is highly insoluble in water, into a solid.
  • the challenge of using lime-based products is that calcium hydroxide is only sparingly soluble in water and must dissolve before the reactions necessary to cause precipitation can occur.
  • a method and apparatus are needed for removing ammonia along with the other nutrients which is acceptable for salt water, soil, and fresh water applications.
  • a method and apparatus for simultaneously removing ammonia along with the other nutrients is needed.
  • embodiments include a method of recovering ammonia and precipitating phosphorous from a waste stream, comprising separating an anaerobically digested waste stream into a solids-rich stream and an solids-depleted stream; reacting the solids-depleted stream with lime or a lime-based solution to form a first mixture; introducing compressed gas into the first mixture to form an aerated first mixture; passing the aerated first mixture through a reaction zone; passing the aerated first mixture stream through a fiocculation zone, where a flocculation agent is added to the aerated first mixture to form a second mixture; passing the second mixture stream through a settling zone, thereby removing precipitated settled solids from the second mixture stream and removing an ammonia-laden gas and a softened solids-depleted stream from the second mixture stream via sparged compressed gas; scrubbing the ammonia-laden gas using an acidic solution to remove ammonia therefrom; and passing at least
  • Embodiments further include an apparatus for removing ammonia and phosphorous from a waste stream, comprising a reacting and settling vessel comprising at least one reaction chamber for reacting a lime or lime-based product with a solids-depleted stream, at least one flocculation chamber for adding a flocculating agent to the solids-depleted stream, at least one settling chamber for settling and precipitating a solids stream from an ammonia-laden gas, and a capability to recirculate at least a portion of settled solids back to the at least one reaction chamber; at least one gas compressor for compressing a gas prior to its introduction into the at least one reaction chamber; and at least one ammonia absorption column for separating ammonia from the compressed gas subsequent to its contact in at least one of the chambers of the reacting and settling vessel, wherein the compressed gas removes ammonia from the solids-depleted stream and enhances phosphorous precipitation.
  • a reacting and settling vessel comprising at least one reaction chamber for react
  • Further embodiments include a method for slow softening a waste stream having soluble calcium compounds present therein, wherein at least one alkaline precipitating agent is admixed with the waste stream to be softened in a mixing zone and then the calcium compounds are changed inside a reaction zone through which the waste stream passes after being admixed with the alkaline precipitating agent into insoluble calcium carbonate matter which is subsequently changed in a flocculation zone into settleable floes by the addition of a flocculating agent containing trivalent metal ions, comprising mixing the waste stream, the alkaline precipitating agent, and an agitated liquid, gas, or combination of liquid and gas with finely divided crystalline calcium carbonate in the mixing zone prior to the addition of and in the absence of the flocculation agent to form seeds for the calcium carbonate matter which newly precipitates from the waste stream inside the reaction zone; presettling and discharging at least a part of the insoluble calcium carbonate matter which has been precipitated inside the reaction zone; passing the waste stream into a flocculating
  • FIG. 1 is a flow chart of an embodiment of a nutrient recovery process.
  • Embodiments of the present invention include a method and device for simultaneously, efficiently, and cost-effectively removing ammonia and phosphorous from waste water.
  • the nutrient recovery process and system of some embodiments involves using calcium hydroxide or calcium oxide to raise stream pH, soften and precipitate phosphorous, and recover ammonia and/or potassium.
  • Useful and valuable quantities of ammonia are recovered from a waste stream or landfill leachate by use of processes and equipment of embodiments.
  • the waste stream may result from any process known to those skilled in the art which generates waste containing ammonia or the precursors to ammonia (nitrogen- containing wastes), including but not limited to streams from anaerobic digestion of sewage or animal wastes or streams from industrial processes such as rendering operations and coke and chemical manufacturing processes.
  • embodiments of the present invention advantageously allow concurrent and effective removal of ammonia, phosphorus, and possibly other nutrients. Processes and devices of embodiments cost-effectively and efficiently enhance phosphorous recovery while allowing for recovery of ammonia from the waste stream.
  • a lime sludge forms to allow precipitation of the phosphorous and other solids.
  • Embodiments include providing front end treatment of a waste stream using a lime product in a lime softener reactor and settler and introducing agitated gas (gas bubbles), such as air or carbon dioxide, into the waste stream to efficiently and effectively recover ammonia and potassium and precipitate phosphorus.
  • gas bubbles such as air or carbon dioxide
  • the gas bubbles are introduced into the lime softener reactor and settler while mixing the lime and waste stream, thereby enhancing precipitation of phosphorus as well as recovering ammonia-laden gas while mixing the lime and waste stream.
  • introducing the gas bubbles into the lime softener reactor and settler not only removes ammonia from the waste stream, but also causes improved precipitation of the phosphorous (improved in relation to the precipitation of phosphorous that occurs when only the lime softener reactor and settler are utilized without the gas bubbles).
  • Further embodiments provide front end treatment of the waste stream using the lime product in the lime softener reactor and settler and vacuum stripping the ammonia from the reacted and settled stream (e.g., using a vacuum stripper/stripping unit or a vacuum distillation unit) to efficiently recover ammonia from the waste stream.
  • This embodiment may also include introducing the agitated gas (gas bubbles) into the lime softener reactor and settler prior to the vacuum stripping of the ammonia (e.g., while mixing the lime product and the waste stream).
  • lime is utilized in a solid/liquid system to recover ammonia from a waste stream, the system being calcium-based.
  • FIG. 1 shows an embodiment of a nutrient recovery process.
  • the waste stream which may include for example sewage sludge or animal wastes (but may also include waste resulting from industrial processes such as rendering operations or from coke or chemical manufacture), is anaerobically digested by an anaerobic digester 1 to produce a digested sludge or waste stream W.
  • This digested waste stream W typically has an at least substantially neutral pH value (a pH of approximately 7).
  • the digested sludge W is then separated into a solids-rich stream SR and a solids-depleted stream SD.
  • the digested sludge W may be separated into these streams SD and SR by one or more separating devices 2, which may include one or more of any separating devices known to those skilled in the art, including but not limited to one or more centrifuges, filter presses, and/or settling basins.
  • the solids-depleted stream SD contains the bulk of the water as well as a variety of chemicals dissolved and suspended in the water, the dissolved and suspended chemicals typically including ammonia nitrogen (NH 3 -N), calcium carbonate (CaCO 3 ) as the hardness, phosphate, and suspended solids.
  • NH 3 -N ammonia nitrogen
  • CaCO 3 calcium carbonate
  • the solids-depleted stream SD may contain other chemicals in addition to those listed above, and/or the constituents may be present in the solids-depleted stream SD in different concentrations.
  • the solids-depleted stream SD may be a centrate stream, while the solids rich stream SR may be a bio-solids cake.
  • alkali earth metals e.g., calcium
  • these alkali earth metals are removable from the solids-depleted stream SD by lime or soda-lime softening (increasing the pH of the solids-depleted stream SD to form a more basic solution).
  • the solids-depleted stream SD is introduced into a lime softener reactor and settler apparatus 25, which includes one or more reaction chambers 5, one or more flocculation chambers 6, and one or more settling chambers 7, the solids-depleted stream SD in a preferred embodiment flowing through these chambers 5, 6, and 7 in that order as shown in Figure 1.
  • the lime softener reactor and settler apparatus 25 precipitates calcium carbonate and forms and precipitates calcium phosphate, magnesium ammonium phosphate, and/or struvite as well as converts the ammonium ion into ammonia.
  • the conversion of ammonium bicarbonate to free ammonia and calcium carbonate is shown in the following reaction:
  • a device and method usable as at least a portion of the lime softener reactor and settler apparatus 25 is shown and described in U.S. Patent Number 4,209,395 issued June 24, 1980, which is herein incorporated by reference in its entirety.
  • this patent by recycling a stream containing a high percentage of crystallized solid particles to serve as nucleation sites for additional crystal growth, super-saturation of calcium carbonate is avoided and the alkali earth ions may be precipitated from the solution.
  • additional soda ash may be added as a source of carbonate ion and to further raise the pH of the resulting stream.
  • the recirculation of the particles also helps reduce mineral deposit on the surfaces of the equipment.
  • the system and recirculation rate is designed such that the available surface area of the recycled particles is substantially greater than the equipment surface area, minimizing precipitation on equipment surfaces.
  • a multi- chambered lined and covered lagoon may be utilized to accomplish this same result.
  • the above-referenced patent does not allow for or address ammonia removal.
  • the embodiment of Figure 1 allows for ammonia removal in addition to phosphorus and alkali earth metals removal.
  • the solids-depleted stream SD is reacted with lime L (or soda lime), which is introduced into the reaction chamber(s) 5 from a lime storage tank 4.
  • the lime stream L may utilize calcium oxide (e.g., a slaked lime such as calcium carbonate CaCO 3 ) and/or calcium hydroxide (quick lime, CO 3 ) to minimize the use of salt (sodium chloride), soda ash, or caustic soda, especially where the treated water is discharged into fresh water or applied to soils where minimal salt content in the treated water is desirable.
  • a further advantage to the use of the lime L rather than the soda ash or caustic soda is that nearly all forms of lime, including quick lime and slaked lime, are much less costly on a chemical equivalent basis than caustic soda or soda ash.
  • caustic soda or soda ash may be utilized in addition to or in lieu of the lime L to increase the pH of the solids-depleted stream SD.
  • a compressed gas G such as nitrogen, air, carbon dioxide, biogas, or mixtures of one or more of these gases is added to the reaction chambers 5 to generate bubbles, thereby providing agitation in the reaction chamber(s) 5 to allow for ammonia removal from the solids-depleted stream SD.
  • the gas G may be compressed using a compressor 16 or a blower.
  • the contents of the reaction chamber(s) 5 are agitated by fluid pumping into the chamber(s) 5 in lieu of or in addition to the compressed gas G, and the unit 16 is a liquid pump.
  • the gas G may be heated after its compression, for example using an optional gas heater 12.
  • Heating the gas G allows the use of a heat exchanger that does not directly contact the liquid stream, which avoids fouling of the heat exchanger from the precipitating particles in the liquid stream, hi the reaction chamber(s) 5, the gas bubbles agitate the liquid stream flowing through the reaction chamber(s) 5 and, when the gases contain oxygen, assist in the conversion of ferrous to ferric ions. Additionally, the dissolving lime converts ammonium ion into ammonia which may escape into the sparged gas from the settling chamber(s) 7 to form ammonia-laden gas GA.
  • the engineered vessel for the lime softener reactor and settler apparatus 25 is preferably entirely enclosed and maintained under a slight vacuum.
  • the agitated gas or liquid is added to the reaction chamber(s) 5 may be enough gas/liquid to use the lime L to precipitate out the phosphorous, but not so much gas/liquid that it removes the bulk of the ammonia at the same time.
  • the piping and equipment of the ammonia recovery process and/or the piping or equipment conveying the treated waste stream back to the plant may become damaged or clogged due to the formation of these solids on the walls or other portions of the piping and/or equipment, reducing efficiency of the nutrient recovery system and increasing the cost of the nutrient recovery process.
  • the ammonia-laden gas GA may be scrubbed with an acidic solution to remove the ammonia, which scrubbing may be accomplished using one or more scrubbers, for example one or more acid scrubbers 8, neutral scrubbers 9, and/or caustic scrubbers (not shown).
  • the preferred embodiment includes scrubbing the ammonia-laden gas GA using at least one acid scrubber 8 followed by at least one neutral scrubber 9.
  • the acid scrubber 8 uses an acidic solution to absorb gaseous ammonia into an acid stream, while the neutral scrubber 9 utilizes a neutral solution to protect the compressor/blower 16 from acidic carryover from the acidic scrubber S.
  • the carrier gas G may be recirculated back into the reaction chamber(s) 5 for reuse, or in the alternative, the carrier gas G may be vented, as meets the specific design objectives of the system. Recycling the gas back into the lime softener reactor and settler apparatus 25 greatly diminishes the need for and the required sizes of subsequent odor control equipment. Where the gas G contains carbon dioxide (CO 2 ), a portion of this carbon dioxide would likely react with dissolved calcium in the apparatus 25, thereby advantageously further enhancing precipitation. Passing the ammonia-laden gas GA through the one or more scrubbers 8, 9 permits effective re-use of the gas G.
  • CO 2 carbon dioxide
  • portions of the acidic solution 29 may proceed to product recovery by exiting the acidic scrubber 8 and entering a product recovery tank 18.
  • the acidic scrubber 8 utilizes sulfuric acid (H 2 SO 4 ), and the acidic solution of ammonium salt 29 which enters the product recovery tank 18 is ammonium sulfate ((NH 4 ) 2 SO 4 ).
  • fresh concentrated acid e.g., sulfuric acid
  • liquid from the neutral wash 9 may provide make-up solution to the acid scrubber 8
  • fresh water may provide make-up solution to the neutral scrubber 9.
  • make-up solution(s) potential corrosion in the compressor 16 is limited or eliminated so that a liquid ring compressor is usable if desired.
  • iron fillings and/or colloidal iron may be added and/or a caustic scrubber may be used to further scrub the solution after the ammonia-laden gas GA exits the acid scrubber 8.
  • the solution 26 entering into and present within the flocculation chamber(s) 6 has a higher pH than the pH of the solids-depleted stream SD, preferably a basic pH, most preferably a pH of approximately 10.5 to approximately 11.
  • Calcium bicarbonate is highly soluble in water and the lime and soda-lime softening process works by raising the solids-depleted stream SD pH to a point at which the bicarbonate anion is converted to the carbonate ion (this point of conversion typically occurs at an increased pH of approximately 10.5 to approximately 11).
  • this point of conversion typically occurs at an increased pH of approximately 10.5 to approximately 11.
  • calcium carbonate which is highly insoluble in water, precipitates into a solid, and a variety of other minerals such as calcium phosphate, magnesium ammonium phosphate, and/or struvite will form and precipitate.
  • one or more flocculants F are added to the reacted solution which exits from the reaction chamber(s) 5 to form solution 26, and the precipitates are flocculated.
  • the solution 26 enters the one or more settling chambers 7, where the precipitates are settled.
  • the one or more flocculants may include any flocculant or flocculation agent known to those skilled in the art, including but not limited to salts containing trivalent metal ions such as FeCl 3 or any flocculation agent mentioned in the disclosure of the '395 patent incorporated by reference above.
  • the reaction chamber(s) 5, flocculation chamber(s) 6, and/or settling chamber(s) 7 may be configured and may operate in the same manner as the reaction zone, flocculation zone, and sedimentation/filtration zone, respectively, shown and described in the '395 patent, with the variations to the process/devices described herein.
  • the soda lime softening process may be the same as or similar to the process described in the '395 patent with the variations to the process as described herein.
  • the variations described herein may include the gas agitation.
  • the settled liquid enters a vacuum stripping unit or vacuum stripper 19 (or ammonia absorption column), where the ammonia is removed as a gas 33, particularly in a higher-ammonia discharge or land application case where the settled liquid is a high-pH settled liquid.
  • the soda lime softening effluent 28 may be sent directly to the vacuum stripper 19 without flowing the effluent 28 through the equipment in box 30 and without the additional process steps performed by the equipment in box 30.
  • the vacuum stripper in combination with the front end treatment e.g., the lime softener reactor and settler 25 and/or the air agitation, scrubbing, and/or other process steps prior to the entry of the solution into the vacuum stripper
  • the vacuum stripper in combination with the front end treatment e.g., the lime softener reactor and settler 25 and/or the air agitation, scrubbing, and/or other process steps prior to the entry of the solution into the vacuum stripper
  • the front end treatment e.g., the lime softener reactor and settler 25 and/or the air agitation, scrubbing, and/or other process steps prior to the entry of the solution into the vacuum stripper
  • the ammonia gas 33 may enter a venturi recirculation line 35 and be pumped by pump 21 into the product tank 18. Ultimately, the ammonia gas 33 is captured in a concentrated ammonium salt and acid solution, which capturing may occur in the product tank 18. Flowing into the product tank 18 are the ammonia gas 33 (or 35), the portion of acidic solution 29 exiting from the acid scrubber 8, and an acid stream 36. The acid stream 36 may flow from an acid supply tank 17.
  • a spent-regeneration solution 37 may be recycled into the product tank 18, as described in more detail below in relation to the "optional devices and additional process steps.”
  • the acid supplied by tank 17
  • the product tank 18 includes ammonium sulfate ((NH 4 ) 2 SO 4 ) due to the mixing of the streams 33 (or 35), 29, 36, and optionally the stream 37.
  • Embodiments link the acid scrubber acid solution 29 and the vacuum stripper absorption solution 33 to form a single product of ammonium sulfate or other ammonium salt solution, preferably approximately 40% ammonium sulfate or equivalent other ammonium salt solution (but other ammonium salt product concentrations are within the scope of embodiments of the present invention).
  • centrate stream 34 The portion of the solution exiting the vacuum stripper 19 which is not removed as a gas 33 is an at least partially-treated centrate stream 34.
  • This centrate stream 34 may be further treated by the optional equipment in box 31, but eventually enters the treated water neutralization tank 24 if pH adjustment is necessary or desired, where the centrate stream 34 is neutralized using caustic by caustic stream 40 (which may be supplied from caustic tank 20) and/or acid via acid stream 41 (which may be supplied from acid tank 17).
  • the treated water T may then be returned to the wastewater plant or otherwise discharged from the system.
  • the caustic as well as the acid may be utilized to neutralize the water, preferably modifying the pH of the centrate stream 34 from approximately 10.5 to approximately 6 to approximately 8 (the pH of the treated water T is preferably at least substantially neutral, most preferably having a pH value of approximately 6 to approximately 8). In other alternate embodiments, no pH adjustment is performed on the centrate stream 34 (the treated main-flow stream). If necessary or desired, the pH adjustment may be performed in any manner known to those skilled in the art. In any event, the treated water T may be sent to the irrigation field, applied to land or soil, discharged into fresh water or salt water, stored, and/or returned to the plant.
  • the optional devices include one or more multi-media filters 13, one or more cartridge filters 14, one or more cation exchange softeners or ion exchange columns 15, 22, and associated tanks 23 and pumps (not shown). Ion exchange and the ion exchange process is shown and described in "Ion Exchange Primer," pages 1-12, distributed by Sybron Chemicals, Inc., which is herein incorporated by reference in its entirety. Any of the ion exchange principles, resins, equipment, and operations described in the "Ion
  • the optional equipment shown in boxes 30 and 31 and the process steps performed by this equipment may not be required and therefore may be eliminated.
  • these additional devices 30 and 31 and their associate process steps may be omitted.
  • the devices may only be required where the effluent ammonia must be reduced to a concentration of below approximately 200 ppm, because the vacuum stripper 19 is capable of competently handling a reasonable level of suspended solids.
  • the equipment of boxes 30 and 31 and some or all of the processes performed by the equipment of boxes 30 and 31 may be necessary.
  • the settling device (the settling chamber) 7 may be sized appropriately and its parameters optimized so that the concentration of suspended solids in the settled liquid 28 is in a range suitable for subsequent treatment in a polishing filter such as the shown multi-media filter 13.
  • a polishing filter such as the shown multi-media filter 13.
  • any other type of polishing filter device or method of filtering (and the associated equipment) known to those skilled in the art may be utilized in lieu of or in addition to the multi-media filter 13.
  • the equipment depicted in boxes 30 and 31 operate in the following manner when utilized.
  • the settled liquid high-pH solution (for example, having a pH of approximately 10.5) flows into the multi-media filter 13 (and/or other polishing filter).
  • the backwash or overflow from the multi-media filter 13 may be recirculated back into the system 25, specifically back into one or more of the reaction chambers 5, as overflow stream 43.
  • the overflow stream 43 is recycled back to the front of the soda-lime softener 25.
  • the remainder of the product from the multi-media filter 13 (probably a high-pH solution) flows as stream 44 to a cartridge filter 14 for further filtering of the solution 44.
  • the cartridge filter 14 may be supplemented or eliminated, as desired, and other filters having similar functions known to those skilled in the art may be utilized instead of the cartridge filter 14.
  • the cartridge-filtered stream 45 then flows into an ion exchange column 15, which may be a cation exchange softener.
  • the ion exchange column 15 removes the remaining divalent and trivalent cations from the stream 45.
  • the ion exchange column 15 may be a standard ion exchange column as known to those skilled in the art, and it may be regenerated with sodium chloride (salt) brine and/or with a concentrated ammonium chloride solution (and/or with sodium hydroxide, sodium chloride, brine, or a combination thereof).
  • the ammonium chloride solution is obtainable from the acid scrubber 8, and hydrochloric acid (HCl) may be utilized as the acid.
  • HCl hydrochloric acid
  • the rationale for the use of the chloride is that calcium chloride, which is being removed from the column, is highly soluble. When simplicity is desirable, salt brine may be utilized for this purpose.
  • the stream 32 Upon its exit from the ion exchange column 15, the stream 32 (may be a high-pH stream) enters the vacuum stripper 19 described above. In this embodiment as well as the embodiments where the equipment/processes of boxes 30 and 31 are eliminated, the vacuum stripper unit 19 removes ammonia gas 33 from the stream 32. After the vacuum stripping step, the concentration of residual ammonia in the liquid stream 34 may be approximately 100 ppm to approximately 250 ppm.
  • the ammonia gas 33 is at least substantially void of other metal cations upon its leaving of the water stream.
  • the ammonia gas 33 may include one or more volatile organics and/or some sulfides, in which case it may be treated as mentioned previously in paragraph [0030] above.
  • the centrate stream 34 may optionally be sent to the equipment shown in box 31, specifically one or more ammonia polishing columns/ion exchange systems 22 to remove any remaining ammonia and/or potassium.
  • a variety of possible columns and resins may be utilized in this ammonia polishing step, including one or more weak acid resins which remove ammonia as ammonia and/or one or more strong acid cation resins which convert ammonia to ammonium ion and remove it as an ion.
  • a strong acid cation resin in the hydrogen form would recover both the potassium and ammonium.
  • the centrate stream 34 may be regenerated with sulfuric acid, preferably approximately 8% sulfuric acid, and the spent regeneration solution may then be sent to the venturi feed tank where it would be used in the vacuum stripping section.
  • the resulting main process flow stream of treated water T is closer to neutral pH and contains low or minimal amounts of ammonia, calcium, suspended solids, phosphorous, potassium, and/or other nutrients, thereby allowing re-use of the treated stream T in a variety of applications or disposal or storage thereof.
  • the above-described devices and methods are especially useful when treating animal wastes where the concentration of ammonia can easily be as high as 8,000 ppm.
  • Table 3 shows the equilibrium of the ammonium ion and ammonia as a function of pH for a solution that contains approximately 1,000 ppm of ammonia as nitrogen (values are for 90°F and are approximate):
  • lime addition is capable of achieving a stream pH of approximately 10.5 and this pH is capable of converting the bulk of both the bicarbonate anions in solution to carbonate and the ammonium cations to ammonia
  • significant cost savings are available with the use of lime in place of soda ash or caustic soda.
  • the lime was used to raise the pH to 10.5 and then caustic was used to raise the pH from 10.4 to 10.6.
  • the concentration of bicarbonate was the same as ammonium ion and that all of the bicarbonate was converted to carbonate by lime at pH 10.4. It may be desirable to raise the pH to 10.6 to precipitate the residual magnesium hydroxide as well as further convert ammonium ion to ammonia.
  • the lime would be supplying -2,200 ppm of hydroxyl ion versus 161 ppm for the caustic at the titration end point.
  • the high concentration of ammonia and bicarbonate makes the use of lime even more vitally important because lime is much less costly than caustic and much easier to handle and store.
  • wetted surfaces Before being placed into service in the system, wetted surfaces may be cleaned and/or coated with a film of water repellent and/or one or more chemical-resistant materials such as silicone, Teflon®, and/or hydrocarbon-based grease.
  • chemical-resistant materials minimize the ability of precipitate scale to form on equipment surfaces and facilitate cleaning of the equipment if precipitation did occur.
  • some or all of the gas bubbles may be introduced into the lime softener reactor and settler apparatus 25 as one or more high- velocity jet streams to induce a higher shear rate of ammonia-laden gas from the waste stream W.
  • This higher shear rate may increase system efficiency in the removal of ammonia as well as other nutrients from the waste water W.
  • the product ammonium sulfate may be utilized as a commercial grade fertilizer.
  • the nitrogen in the form of ammonia found in the waste stream is thereby efficiently and cost-effectively converted to a usable product by use of the above-described methods and apparatus.
  • the recovery of ammonia in the form of ammonium sulfate or in any other form using the above-described methods and apparatus advantageously limits nitrogen discharge into bodies of water, as often required by environmental regulations, along with providing a usable end-product (e.g., ammonium sulfate).
  • the above-described nutrient recovery method advantageously involves introducing gas bubbles while mixing the lime or lime-based solution into the waste stream feed, thereby stripping ammonia from the waste stream feed.
  • the above- described process enhances precipitation of phosphorous from the waste stream feed. Accordingly, both ammonia recovery and phosphorous recovery are accomplished efficiently and cost-effectively upon the introduction of gas bubbles into the system 25.
  • the above-described nutrient recovery method combines front-end treatment of the waste stream with vacuum stripping, also enhancing nutrient recovery from the waste stream.
  • the brine may be substituted with sodium hydroxide, sodium chloride, brine, or a combination or solution thereof.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Removal Of Specific Substances (AREA)
  • Physical Water Treatments (AREA)

Abstract

Les modes de réalisation de la présente invention comprennent un procédé et un appareil pour la récupération efficace à peu de frais de nutriments dans un flux de déchets. Les nutriments récupérés peuvent comprendre de l'ammoniac, du phosphore et/ou du potassium. La récupération de l'ammoniac et du phosphore peut être simultanée. Dans certains modes de réalisation, l'ammoniac est récupéré avec d'autres nutriments au moyen de chaux ou de produits à base de chaux.
PCT/US2006/034683 2006-09-06 2006-09-06 Procédé de récupération de nutriments WO2008030234A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2006/034683 WO2008030234A1 (fr) 2006-09-06 2006-09-06 Procédé de récupération de nutriments

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2006/034683 WO2008030234A1 (fr) 2006-09-06 2006-09-06 Procédé de récupération de nutriments

Publications (1)

Publication Number Publication Date
WO2008030234A1 true WO2008030234A1 (fr) 2008-03-13

Family

ID=39157535

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2006/034683 WO2008030234A1 (fr) 2006-09-06 2006-09-06 Procédé de récupération de nutriments

Country Status (1)

Country Link
WO (1) WO2008030234A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010136046A1 (fr) * 2009-05-28 2010-12-02 N.E.S. Aps Procédé et système pour la séparation d'une boue animale
EP2415715A1 (fr) * 2010-08-03 2012-02-08 Enviro-Chemie GmbH Dispositif et procédé de séparation sélective de substances inorganiques dans un système pour le traitement anaérobie des eaux usées
EP2489641A1 (fr) * 2011-02-15 2012-08-22 Ostara Nutrient Recovery Technologies Inc. Procédés et appareil pour la récupération de struvite comprenant une injection de CO2 en amont
EP3138814A1 (fr) * 2015-09-04 2017-03-08 Rainer Fülling Procede de production de sels de potassium anorganiques provenant d'anaerobies et/ou traitement aerobie d'au moins en partie de substrats accessibles
CN106474812A (zh) * 2015-08-26 2017-03-08 中国石油化工股份有限公司 稀硫铵液浓缩预处理系统及方法
CN109942150A (zh) * 2019-03-22 2019-06-28 南京大学盐城环保技术与工程研究院 一种废植物油利用生产废水的处理方法
CN112368240A (zh) * 2018-07-26 2021-02-12 三菱重工工程株式会社 能量气体精制排水的处理装置及能量气体精制排水的处理方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4209395A (en) * 1975-01-14 1980-06-24 Passavant-Werke Michelbacher Huette Process for slow softening water
US6423228B2 (en) * 1998-08-10 2002-07-23 Sharp Kabushiki Kaisha Treating fluorine waste water containing organic matter, phosphor and hydrogen peroxide

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4209395A (en) * 1975-01-14 1980-06-24 Passavant-Werke Michelbacher Huette Process for slow softening water
US6423228B2 (en) * 1998-08-10 2002-07-23 Sharp Kabushiki Kaisha Treating fluorine waste water containing organic matter, phosphor and hydrogen peroxide

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010136046A1 (fr) * 2009-05-28 2010-12-02 N.E.S. Aps Procédé et système pour la séparation d'une boue animale
EP2415715A1 (fr) * 2010-08-03 2012-02-08 Enviro-Chemie GmbH Dispositif et procédé de séparation sélective de substances inorganiques dans un système pour le traitement anaérobie des eaux usées
EP2489641A1 (fr) * 2011-02-15 2012-08-22 Ostara Nutrient Recovery Technologies Inc. Procédés et appareil pour la récupération de struvite comprenant une injection de CO2 en amont
CN106474812A (zh) * 2015-08-26 2017-03-08 中国石油化工股份有限公司 稀硫铵液浓缩预处理系统及方法
EP3138814A1 (fr) * 2015-09-04 2017-03-08 Rainer Fülling Procede de production de sels de potassium anorganiques provenant d'anaerobies et/ou traitement aerobie d'au moins en partie de substrats accessibles
CN112368240A (zh) * 2018-07-26 2021-02-12 三菱重工工程株式会社 能量气体精制排水的处理装置及能量气体精制排水的处理方法
EP3782959A4 (fr) * 2018-07-26 2021-06-16 Mitsubishi Heavy Industries Engineering, Ltd. Appareil et procédé de traitement d'eaux usées de purification de gaz d'énergie
CN109942150A (zh) * 2019-03-22 2019-06-28 南京大学盐城环保技术与工程研究院 一种废植物油利用生产废水的处理方法
CN109942150B (zh) * 2019-03-22 2021-11-19 南京大学盐城环保技术与工程研究院 一种废植物油利用生产废水的处理方法

Similar Documents

Publication Publication Date Title
US20080053913A1 (en) Nutrient recovery process
KR101329523B1 (ko) 스트림으로부터의 암모늄/암모니아 제거
KR100190220B1 (ko) 이온교환수지를 사용하여 폐수를 처리하는 수처리장치
AU2002220093B2 (en) Method and apparatus for treatment of water and wastewater
US10773986B2 (en) System and process for treating produced and frac flowback waters
US20150315054A1 (en) System for treating coal gasification wastewater, and method for treating coal gasification wastewater
CN103813987A (zh) 含磷酸盐的废水的处理以及氟硅酸盐和磷酸盐的回收
WO2008030234A1 (fr) Procédé de récupération de nutriments
US9169144B2 (en) High rate chemical softening process
US20210317016A1 (en) Methods and apparatus for nutrient and water recovery from waste streams
CN107915354A (zh) 一种脱硫废水零排放及资源化利用装置和方法
US4483772A (en) Process for treating aqueous effluents
KR20090069904A (ko) 철강산업의 산세액 처리방법
WO2008030235A2 (fr) Procédé de récupération d'ammoniac
KR20160003936A (ko) 질소와 인 제거, 회수 장치 및 그 방법
KR100722655B1 (ko) 알칼리도 첨가형 황메디아와 분리막이 침적된 고도처리장치
Huang et al. Complex treatment of the ammonium nitrogen wastewater from rare-earth separation plant
JP2001239273A (ja) ホウ素およびフッ素含有水の処理方法
JP4543478B2 (ja) ホウ素含有水の処理方法
US11834358B2 (en) Process for treating frac flowback and produced water including naturally occurring radioactive material
CN109626623A (zh) 一种含铜和氨氮废水的处理工艺
US9650266B2 (en) Method of treating suspended solids and heavy metal ions in sewage
CZ305399B6 (cs) Způsob neutralizace odpadních oplachových vod z moříren nerezových ocelí
KR101624257B1 (ko) 인 제거, 회수 장치 및 그 방법
JP3614251B2 (ja) 下水処理における硫化水素の抑制方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 06814218

Country of ref document: EP

Kind code of ref document: A1

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 06814218

Country of ref document: EP

Kind code of ref document: A1