EP0000230B1 - Process for the biological purification of waste water - Google Patents
Process for the biological purification of waste water Download PDFInfo
- Publication number
- EP0000230B1 EP0000230B1 EP78200057A EP78200057A EP0000230B1 EP 0000230 B1 EP0000230 B1 EP 0000230B1 EP 78200057 A EP78200057 A EP 78200057A EP 78200057 A EP78200057 A EP 78200057A EP 0000230 B1 EP0000230 B1 EP 0000230B1
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- EP
- European Patent Office
- Prior art keywords
- process according
- hydrolysate
- hydrolysis
- sludge
- waste water
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired
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- 238000000034 method Methods 0.000 title claims description 30
- 238000000746 purification Methods 0.000 title claims description 22
- 239000002351 wastewater Substances 0.000 title claims description 20
- 239000010802 sludge Substances 0.000 claims description 38
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 31
- 239000000725 suspension Substances 0.000 claims description 28
- 239000000413 hydrolysate Substances 0.000 claims description 25
- 230000007062 hydrolysis Effects 0.000 claims description 23
- 238000006460 hydrolysis reaction Methods 0.000 claims description 23
- 229910000069 nitrogen hydride Inorganic materials 0.000 claims description 16
- 239000007787 solid Substances 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 8
- 229910021529 ammonia Inorganic materials 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 4
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 3
- 241000283690 Bos taurus Species 0.000 claims description 3
- 239000001099 ammonium carbonate Substances 0.000 claims description 3
- 235000012501 ammonium carbonate Nutrition 0.000 claims description 3
- 230000009615 deamination Effects 0.000 claims description 3
- 238000006481 deamination reaction Methods 0.000 claims description 3
- 239000007789 gas Substances 0.000 claims description 2
- 239000011261 inert gas Substances 0.000 claims description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 15
- 150000001413 amino acids Chemical class 0.000 description 11
- 239000011368 organic material Substances 0.000 description 8
- 239000000126 substance Substances 0.000 description 8
- 238000003795 desorption Methods 0.000 description 7
- 108010009736 Protein Hydrolysates Proteins 0.000 description 6
- 244000005700 microbiome Species 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 150000001720 carbohydrates Chemical class 0.000 description 3
- 235000014633 carbohydrates Nutrition 0.000 description 3
- 239000003925 fat Substances 0.000 description 3
- 229910001415 sodium ion Inorganic materials 0.000 description 3
- 239000002352 surface water Substances 0.000 description 3
- 150000008574 D-amino acids Chemical class 0.000 description 2
- 150000008575 L-amino acids Chemical class 0.000 description 2
- 102000015636 Oligopeptides Human genes 0.000 description 2
- 108010038807 Oligopeptides Proteins 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 2
- 239000000292 calcium oxide Substances 0.000 description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 229910001385 heavy metal Inorganic materials 0.000 description 2
- 229910010272 inorganic material Inorganic materials 0.000 description 2
- 239000011147 inorganic material Substances 0.000 description 2
- 238000005342 ion exchange Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229910017464 nitrogen compound Inorganic materials 0.000 description 2
- 150000002830 nitrogen compounds Chemical class 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000008213 purified water Substances 0.000 description 2
- 230000006340 racemization Effects 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 238000005904 alkaline hydrolysis reaction Methods 0.000 description 1
- 238000005576 amination reaction Methods 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- 210000002421 cell wall Anatomy 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 102000004196 processed proteins & peptides Human genes 0.000 description 1
- 108090000765 processed proteins & peptides Proteins 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 150000003212 purines Chemical class 0.000 description 1
- 150000003230 pyrimidines Chemical class 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/18—Treatment of sludge; Devices therefor by thermal conditioning
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23J—PROTEIN COMPOSITIONS FOR FOODSTUFFS; WORKING-UP PROTEINS FOR FOODSTUFFS; PHOSPHATIDE COMPOSITIONS FOR FOODSTUFFS
- A23J1/00—Obtaining protein compositions for foodstuffs; Bulk opening of eggs and separation of yolks from whites
- A23J1/001—Obtaining protein compositions for foodstuffs; Bulk opening of eggs and separation of yolks from whites from waste materials, e.g. kitchen waste
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S426/00—Food or edible material: processes, compositions, and products
- Y10S426/807—Poultry or ruminant feed
Definitions
- the invention relates to a process for biological purification of waste water, in which an aqueous suspension of the surplus sludge formed during the purification is hydrolyzed in a basic medium and at an elevated temperature.
- a process of this kind is known from the Netherlands Patent Application 6, 911,163.
- the sludge formed is hydrolyzed with the aid of sodium hydroxide or, possibly, calcium oxide.
- the resulting solid matter mainly consisting of inorganic salts and waterinsoluble organic substances, like cell walls which are not, or only partly, hydrolyzed, is filtered off and subjected to further processing.
- the hydrolysate which consists of an aqueous solution of mainly organic material and sodium salts, is returned to the purification plant.
- Sodium hydroxide is here used for hydrolysis of sludge, as a result of which the hydrolysate contains rather large quantities of sodium ions.
- the hydrolysate which mainly consists of an aqueous solution of amino acids, oligopeptides and hydrolysis products of carbohydrates and fats, these sodium ions present problems.
- the basic amino acids are commercially important components of the hydrolysate. If one wants to recover these from the hydrolysate by means of selective ion exchange, all sodium ions present should be removed first, owing to which this process becomes unattractive economically.
- the purpose of the invention is to provide a process in which these disadvantages do not occur.
- the process according to the invention is characterized in that the suspension of the sludge is given a pH value of between 8 and 11 and that hydrolysis is carried out in the presence of a volatile base at a temperature of between 90 and 300 °C, which base is expelled from the hydrolysate formed after the hydrolysis has been terminated.
- a volatile base at a temperature of between 90 and 300 °C, which base is expelled from the hydrolysate formed after the hydrolysis has been terminated.
- ammonia or a bound form thereof e.g. ammonium carbonate
- the ammonia that has been removed from the hydrolysate is returned to the hydrolysis stage.
- the hydrolysis is, preferably, carried out at a temperature of between 90 and 200 °C.
- a process of this kind brings great advantages over known processes. Since, at the pH value applied, practically no racemization of amino acids occurs, a hydrolysate is obtained which mainly contains the amino acids and oligopeptides occuring in nature.
- the process according to the invention has the great advantage that it entails practically no extra costs for chemicals.
- the volatile base used like ammonia, is recovered by stripping the liquid, e.g. with an inert gas or gasmixture like air or steam, and can be refused. Without much trouble the residual content of ammonia can be reduced to 10 ppm after the stripping. If sodium hydroxide or calcium oxide is used, new chemicals must continually be supplied, which places a heavy financial burden on the waste water purification. Moreover, it may be necessary first to neutralize the hydrolysate before it can be used further. It is preferred that, after the solid matter and the volatile base have been separated off, the hydrolysate be further processed to economically attractive products.
- hydrolysate may be the processing into cattle feed, while, in certain cases, it may be the best solution to use the hydrolysate as carbon source in the denitrification step of an industrial waste water purification plant, possibly after one or more nitrogen compounds have been separated off.
- the hydrolysate may also be mixed with the raw waste water and be passed through the entire plant, during which, contrary to the known process, no disturbance of the pH equilibrium in the plant occurs. Returning of the hydrolysate to the waste water purification plant, however, is only possible if one has a waste water purification in which also nitrogen compounds are removed, because otherwise an unacceptable amount of nitrate will be discharged into the surface water.
- the process according to the invention can be realized at the usual pressures for handling aqueous NH 3 solutions.
- the pressure lies between 0.1 - 5 MPa.
- the concentration of ammonia and/or ammonium carbonate amounts preferably to 2 to 14 N. It is possible to carry out the hydrolysis under such conditions that complete or partial de-amination of the amino acids present occurs. In the case of a return of the hydrolysate to the waste water purification plant this brings the advantage that a substantially smaller nitrogen load occurs.
- For deamination to be achieved it is necessary to work at higher temperatures and NH 3 concentrations, for instance a temperature above 150 °C and a concentration of between 4 and 14 N NH 3 . If it should not be the intention to deaminate, it is to be preferred to work at temperatures of between 90 and 180 °C and at an NH 3 concentration of between 2 and 6 N NH 3 .
- the sludge suspension to be hydrolyzed contains, depending on the type of plant of origin, varying contents of sludge (dry matter). This may vary between less than 1 % by weight and more than 35 % by weight.
- Figure 1 of the drawing shows a possible embodiment of the process according to the invention
- Figure 2 shows another embodiment thereof.
- FIG. 1 shows a diagram for a process for purification of waste water according to the invention.
- Waste water here enters via line 1 biological purification plant 2, here indicated as a block.
- the purified waste water which contains suspended biologically activated sludge, is led through line 3 to section 4, where the sludge settles and thickens.
- Via line 5 purified water is discharged into surface water or for further treatment, for instance with chlorine.
- Via line 6 a sludge suspension from section 4 is recycled to the biological purification plant.
- Via line 7 a concentrated sludge suspension is passed to heat exchanger 8.
- Via line 9 the heated suspension is led into hydrolysis column 10.
- Via line 11 a gas mixture of NH 3 and steam originating in heater 12 is supplied.
- hydrolysis column 10 In heater 12 the mixture of NH 3 and steam is heated with the aid of steam coil 13.
- the hydrolyzed sludge suspension leaves hydrolysis column 10 via line 14.
- filtration equipment 15 which may, for instance, consist of filters, sieve bends or centrifuges, this suspension is split up into a hydrolysate and solid matter.
- the solid matter is discharged via line 16.
- the hydrolysate proceeds to desorption column 18.
- FIG 2 in which the various reference numbers have the same meaning as in Figure 1, shows another embodiment of the process according to the invention.
- Waste water here enters biological purification plant 2 via line 1.
- the purified waste water which contains suspended activated sludge, is led through line 3 to section 4, where the sludge settles and thickens.
- Via line 5 purified water is discharged.
- Via line 6 part of the sludge suspension from section 4 is recycled to the purification plant.
- a concentrated sludge suspension is led to static mixer 23, in which this suspension is mixed with hydrolyzed sludge that is supplied through line 24.
- the mixture is passed to heat exchanger 8 via line 25.
- the heated suspension is led into hydrolysis column 10 via line 9.
- Via line 26 a steam/NH 3 mixture is led into hydrolysis column 10.
- Via line 14 the treated sludge suspension is discharged. Part of this suspension is mixed with the sludge suspension from section 4, another part is supplied to desorption column 18 via line 27. Via line 19 the steam required for the desorption and the hydrolysis is supplied.
- the chemical oxygen demand (COD) is given in the last column. This is a measure of the hydrolysis of the biologically active sludge.
- Waste water from a chemical complex is supplied to a plant as described in Figure 1.
- 32.0 tons/h of sludge suspension is produced, which is discharged from section 4 via line 6.
- the sludge suspension contains 20 % of sludge (dry matter), approximately 75 % of which is inorganic material and approximately 25 % organic material.
- the organic material mainly consists of microorganisms and these principally contain amino acids, carbohydrates and fats in a ratio of 5 : 4 : 1.
- This suspension is hydrolyzed in hydrolysis column 10 with the aid of 2 tons/h of NH 3 and steam at a temperature of 130°C and a pressure of 0.7 MPa.
- the hydrolyzed sludge is separated, in 15, into 2.4 tons/h of solid matter and 35.6 tons/h of hydrolysate, which contains 0.8 ton/h of organic material and 32.8 tons/h of water.
- the solid matter contains 90 % of the heavy metals which were present in the sludge suspension.
- the hydrolysate is treated in desorption column 18 with steam of 1.6 MPa, all NH 3 escaping and being recycled via line 20.
- Waste water from a chemical complex is supplied to a plant as described in Figure 2.
- the sludge suspension contains 20 % of sludge (dry matter), approximately 75 % of which is inorganic material and approximately 25 % organic material.
- the organic material mainly consists of microorganisms and these principally contain amino acids, carbohydrates and fats in a ratio of 5 : 4 : 1.
- This suspension is hydrolyzed in hydrolysis column 10 with the aid of 56.8 tons/day of NH 3 /steam mixture at a temperature of 130°C and a pressure of 10 ats abs.
- the hydrolysate is treated in desorption column 18 with steam of 1 MPa, all NH 3 and part of the steam escaping and being recycled via line 20.
- the hydrolyzed sludge is separated in 15 into 37.5 tons/h of solids matter and 296.7 tons/day of hydrolysate, which contains 17.5 tons/day of organic material and 279.2 tons/day of water.
- the solid mater contains 90 % of the heavy metals that were present in the sludge.suspension.
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Food Science & Technology (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Thermal Sciences (AREA)
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Hydrology & Water Resources (AREA)
- Polymers & Plastics (AREA)
- Treatment Of Sludge (AREA)
- Removal Of Specific Substances (AREA)
- Feed For Specific Animals (AREA)
- Fodder In General (AREA)
- Fertilizers (AREA)
Description
- The invention relates to a process for biological purification of waste water, in which an aqueous suspension of the surplus sludge formed during the purification is hydrolyzed in a basic medium and at an elevated temperature.
- A process of this kind is known from the Netherlands
Patent Application 6, 911,163. According to this Application the sludge formed is hydrolyzed with the aid of sodium hydroxide or, possibly, calcium oxide. The resulting solid matter, mainly consisting of inorganic salts and waterinsoluble organic substances, like cell walls which are not, or only partly, hydrolyzed, is filtered off and subjected to further processing. The hydrolysate, which consists of an aqueous solution of mainly organic material and sodium salts, is returned to the purification plant. Although this process produces a great improvement in the disposal of sludge from a waste water purification plant, a few disadvantages are still attached to it. - Sodium hydroxide is here used for hydrolysis of sludge, as a result of which the hydrolysate contains rather large quantities of sodium ions. During a possible subsequent processing of the hydrolysate, which mainly consists of an aqueous solution of amino acids, oligopeptides and hydrolysis products of carbohydrates and fats, these sodium ions present problems. The basic amino acids are commercially important components of the hydrolysate. If one wants to recover these from the hydrolysate by means of selective ion exchange, all sodium ions present should be removed first, owing to which this process becomes unattractive economically.
- Moreover, at the temperature and pH applied for the hydrolysis, racemization of the amino acids and peptides may occur. This causes a mixture of D- and L-amino acids to form which, economically, for instance as cattle feed, is less attractive. There is not much point in adding such a mixture of D- and L-amino acids to human food, since D-amino acids have no value as building material, while addition of a considerable amount of D-amino acids will not be permitted by law. The only possibility in this case is the return to the waste water purification plant, which results in increased investment and variable costs.
- However, from an environmental point of view a process of this kind is not attractive anyway, because all sodium hydroxide used is discharged into the surface water in the form of sodium salts. This brings moreover an extra consumption of chemicals because the hydrolysate, prior to being returned to the plant, must first be neutralized. The pH value and the quantity of liquid are such that interference with the action of the biologically active microorganisms may be the result.
- The purpose of the invention is to provide a process in which these disadvantages do not occur.
- The process according to the invention is characterized in that the suspension of the sludge is given a pH value of between 8 and 11 and that hydrolysis is carried out in the presence of a volatile base at a temperature of between 90 and 300 °C, which base is expelled from the hydrolysate formed after the hydrolysis has been terminated. By preference, ammonia or a bound form thereof (e.g. ammonium carbonate) is applied for volatile base. The ammonia that has been removed from the hydrolysate is returned to the hydrolysis stage. The hydrolysis is, preferably, carried out at a temperature of between 90 and 200 °C.
- A process of this kind brings great advantages over known processes. Since, at the pH value applied, practically no racemization of amino acids occurs, a hydrolysate is obtained which mainly contains the amino acids and oligopeptides occuring in nature.
- It is surprising that it is possible to hydrolyze microorganisms with the aid of a weak base like ammonia. Normally, such hydrolysis is carried out with sodium hydroxide, for the very reason that the high pH values (13 and higher) necessary for hydrolysis of the organic substances present can be reached therewith. According to the invention, however, alkaline hydrolysis of biologically activated sludge is possible already at a pH value of 8.
- The process according to the invention has the great advantage that it entails practically no extra costs for chemicals. The volatile base used, like ammonia, is recovered by stripping the liquid, e.g. with an inert gas or gasmixture like air or steam, and can be refused. Without much trouble the residual content of ammonia can be reduced to 10 ppm after the stripping. If sodium hydroxide or calcium oxide is used, new chemicals must continually be supplied, which places a heavy financial burden on the waste water purification. Moreover, it may be necessary first to neutralize the hydrolysate before it can be used further. It is preferred that, after the solid matter and the volatile base have been separated off, the hydrolysate be further processed to economically attractive products. Here, one may think of recovery of one or more of the amino acids present, for instance with the aid of selective ion exchange or crystallization. In addition, it is possible to recover aromatic nitrogen bases. Particularly those bases are important that are based on pyrimidines and/or purines. These originate in, among others, the genetic material of the microorganisms in the sludge. Another application of the hydrolysate may be the processing into cattle feed, while, in certain cases, it may be the best solution to use the hydrolysate as carbon source in the denitrification step of an industrial waste water purification plant, possibly after one or more nitrogen compounds have been separated off. In addition, the hydrolysate may also be mixed with the raw waste water and be passed through the entire plant, during which, contrary to the known process, no disturbance of the pH equilibrium in the plant occurs. Returning of the hydrolysate to the waste water purification plant, however, is only possible if one has a waste water purification in which also nitrogen compounds are removed, because otherwise an unacceptable amount of nitrate will be discharged into the surface water.
- The process according to the invention can be realized at the usual pressures for handling aqueous NH3 solutions. By preference, the pressure lies between 0.1 - 5 MPa. The concentration of ammonia and/or ammonium carbonate amounts preferably to 2 to 14 N. It is possible to carry out the hydrolysis under such conditions that complete or partial de-amination of the amino acids present occurs. In the case of a return of the hydrolysate to the waste water purification plant this brings the advantage that a substantially smaller nitrogen load occurs. For deamination to be achieved it is necessary to work at higher temperatures and NH3 concentrations, for instance a temperature above 150 °C and a concentration of between 4 and 14 N NH3. If it should not be the intention to deaminate, it is to be preferred to work at temperatures of between 90 and 180 °C and at an NH3 concentration of between 2 and 6 N NH3.
- The sludge suspension to be hydrolyzed contains, depending on the type of plant of origin, varying contents of sludge (dry matter). This may vary between less than 1 % by weight and more than 35 % by weight.
- A possible embodiment of the process according to the invention is described with the aid of the drawing, but is not limited thereto.
- Figure 1 of the drawing shows a possible embodiment of the process according to the invention, and Figure 2 shows another embodiment thereof.
- Figure 1 shows a diagram for a process for purification of waste water according to the invention. Waste water here enters via line 1
biological purification plant 2, here indicated as a block. Depending on the kind of waste water, the design of this plant will be more, or less, complicated. The purified waste water, which contains suspended biologically activated sludge, is led through line 3 tosection 4, where the sludge settles and thickens. Via line 5 purified water is discharged into surface water or for further treatment, for instance with chlorine. Via line 6 a sludge suspension fromsection 4 is recycled to the biological purification plant. Via line 7 a concentrated sludge suspension is passed toheat exchanger 8. Via line 9 the heated suspension is led intohydrolysis column 10. Via line 11 a gas mixture of NH3 and steam originating inheater 12 is supplied. - In
heater 12 the mixture of NH3 and steam is heated with the aid ofsteam coil 13. The hydrolyzed sludge suspension leaveshydrolysis column 10 vialine 14. Infiltration equipment 15, which may, for instance, consist of filters, sieve bends or centrifuges, this suspension is split up into a hydrolysate and solid matter. The solid matter is discharged vialine 16. Throughline 17 the hydrolysate proceeds todesorption column 18. - In this column the NH3 is desorbed with the aid of steam which is introduced, via
line 19, intodesorption column 18 directly. The desorbed NH3, together with a quantity of steam, is recycled toheater 12 vialine 20. Vialine 21 the hydrolysate leavesdesorption column 18. After heat exchange with the suspension from settlingbasin 4 inheat exchanger 8 the hydrolysate is discharged vialine 22. - Figure 2, in which the various reference numbers have the same meaning as in Figure 1, shows another embodiment of the process according to the invention.
- Waste water here enters
biological purification plant 2 via line 1. The purified waste water, which contains suspended activated sludge, is led through line 3 tosection 4, where the sludge settles and thickens. Via line 5 purified water is discharged. Vialine 6 part of the sludge suspension fromsection 4 is recycled to the purification plant. - Via line 7 a concentrated sludge suspension is led to
static mixer 23, in which this suspension is mixed with hydrolyzed sludge that is supplied throughline 24. The mixture is passed toheat exchanger 8 vialine 25. The heated suspension is led intohydrolysis column 10 via line 9. Via line 26 a steam/NH3 mixture is led intohydrolysis column 10. Vialine 14 the treated sludge suspension is discharged. Part of this suspension is mixed with the sludge suspension fromsection 4, another part is supplied todesorption column 18 vialine 27. Vialine 19 the steam required for the desorption and the hydrolysis is supplied. - Via
line 21 the hydrolyzed sludge suspension is discharged. After heat exchange inheat exchanger 8 the suspension is led intofiltration equipment 15 vialine 28 and separated into solid matter, which is discharged via 16, and liquid, which is discharged via 29. - A number of tests have been carried out on a laboratory scale in which aqueous sludge suspensions from a biological purification plant have been hydrolyzed in a basic medium, 100 ml of a 10 % sludge suspension in water has been hydrolyzed in a basic medium for a certain time at a variable temperature. The results are rendered in the table.
-
- This table shows clearly that is is very well possible to practically completely hydrolyze the sludge with NH3 or (NH4)2C03.
- It can also be seen that at less mild reaction conditions the COD content becomes lower, which points to deamination.
-
- At a sludge production of 32.0 tons/h as in example 1, this results in an amino acid quantity of approximately 24 kg/h.
- The invention will now be elucidated with the aid of a few examples, but is not limited thereto.
- Waste water from a chemical complex is supplied to a plant as described in Figure 1. During the purification of the waste water 32.0 tons/h of sludge suspension is produced, which is discharged from
section 4 vialine 6. The sludge suspension contains 20 % of sludge (dry matter), approximately 75 % of which is inorganic material and approximately 25 % organic material. The organic material mainly consists of microorganisms and these principally contain amino acids, carbohydrates and fats in a ratio of 5 : 4 : 1. This suspension is hydrolyzed inhydrolysis column 10 with the aid of 2 tons/h of NH3 and steam at a temperature of 130°C and a pressure of 0.7 MPa. The hydrolyzed sludge is separated, in 15, into 2.4 tons/h of solid matter and 35.6 tons/h of hydrolysate, which contains 0.8 ton/h of organic material and 32.8 tons/h of water. The solid matter contains 90 % of the heavy metals which were present in the sludge suspension. The hydrolysate is treated indesorption column 18 with steam of 1.6 MPa, all NH3 escaping and being recycled vialine 20. Ultimately, 39.0 tons/h of hydrolysate, 0.8 ton of which is organic material, is discharged vialine 23. - Waste water from a chemical complex is supplied to a plant as described in Figure 2. During the purification of the waste water 275 tons/day of sludge suspension in produced, which is discharged from
section 4 vialine 6. The sludge suspension contains 20 % of sludge (dry matter), approximately 75 % of which is inorganic material and approximately 25 % organic material. The organic material mainly consists of microorganisms and these principally contain amino acids, carbohydrates and fats in a ratio of 5 : 4 : 1. This suspension is hydrolyzed inhydrolysis column 10 with the aid of 56.8 tons/day of NH3/steam mixture at a temperature of 130°C and a pressure of 10 ats abs. The hydrolysate is treated indesorption column 18 with steam of 1 MPa, all NH3 and part of the steam escaping and being recycled vialine 20. The hydrolyzed sludge is separated in 15 into 37.5 tons/h of solids matter and 296.7 tons/day of hydrolysate, which contains 17.5 tons/day of organic material and 279.2 tons/day of water. - The solid mater contains 90 % of the heavy metals that were present in the sludge.suspension.
Claims (11)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL7707081A NL7707081A (en) | 1977-06-27 | 1977-06-27 | METHOD FOR THE BIOLOGICAL PURIFICATION OF WASTE WATER. |
NL7707081 | 1977-06-27 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0000230A1 EP0000230A1 (en) | 1979-01-10 |
EP0000230B1 true EP0000230B1 (en) | 1981-01-21 |
Family
ID=19828791
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP78200057A Expired EP0000230B1 (en) | 1977-06-27 | 1978-06-21 | Process for the biological purification of waste water |
Country Status (6)
Country | Link |
---|---|
US (2) | US4190528A (en) |
EP (1) | EP0000230B1 (en) |
JP (1) | JPS5413664A (en) |
DE (1) | DE2860355D1 (en) |
IT (1) | IT1105452B (en) |
NL (1) | NL7707081A (en) |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4289625A (en) * | 1980-01-18 | 1981-09-15 | Institute Of Gas Technology | Hybrid bio-thermal gasification |
US4915840A (en) * | 1988-06-07 | 1990-04-10 | Bioprocess Engineering, Inc. | Process for sludge reduction in an aerobic sludge generating waste treatment system |
US5190655A (en) * | 1989-01-11 | 1993-03-02 | Karlsson Johan L I | Water purification process 2 |
US5360546A (en) * | 1992-04-01 | 1994-11-01 | Ngk Insulators, Ltd. | Method for treating organic sludge |
US5525229A (en) * | 1994-09-14 | 1996-06-11 | North Carolina State University | Process and apparatus for anaerobic digestion |
JP3048889B2 (en) * | 1995-06-29 | 2000-06-05 | 神鋼パンテツク株式会社 | Activated sludge treatment method and activated sludge treatment apparatus therefor |
RU2079454C1 (en) * | 1995-07-18 | 1997-05-20 | Грудинин Владимир Павлович | Method of processing excessive activated sludge |
DE19627875A1 (en) * | 1996-07-11 | 1998-01-15 | Bsbg Bremer Sonderabfall Berat | Process for treating sludges with organic components, in particular sewage sludges |
US6013183A (en) * | 1998-08-05 | 2000-01-11 | Paradigm Environmental Technologies Inc. | Method of liquefying microorganisms derived from biological wastewater treatment processes |
WO2000007947A1 (en) * | 1998-08-07 | 2000-02-17 | Vladimir Pavlovich Grudinin | Method for producing a sulphur-free liquid organic fuel |
DE19940994B4 (en) | 1999-08-28 | 2004-02-26 | Clausthaler Umwelttechnikinstitut Gmbh, (Cutec-Institut) | Process for the removal of sewage sludge |
DE10014185A1 (en) * | 2000-03-23 | 2001-09-27 | Bsbg Bremer Sonderabfall Berat | Hot, high pressure ammonia treatment for excess sewage sludge, subsequently reduces pressure by expansion and recycles steam to heat feedstock |
DE10347476B4 (en) | 2003-10-01 | 2018-07-26 | Pondus Verfahrenstechnik Gmbh | Apparatus and method for cell disruption in sludges |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2012621A (en) * | 1932-02-09 | 1935-08-27 | Hercules Powder Co Ltd | Method of producing anhydrous ammonia |
US3522173A (en) * | 1968-11-12 | 1970-07-28 | Western Mechanical Inc | Water purification method |
NL6911263A (en) * | 1969-07-23 | 1971-01-26 | ||
DE2042785C3 (en) * | 1970-08-28 | 1980-10-23 | Nyby Bruks Ab, Nybybruk (Schweden) | Process for the treatment of used pickling baths containing HNO3 and HF |
CH583525A5 (en) * | 1974-01-16 | 1977-01-14 | Wacker Chemie Gmbh | Prodn of protein-contg feedstuffs - from activated sludge by shock drying |
US4038180A (en) * | 1974-11-22 | 1977-07-26 | Agway, Inc. | Process of dewatering sewage sludge |
GB1533462A (en) * | 1975-02-05 | 1978-11-22 | Sterling Drug Inc | Method and apparatus for ammonia removal from wastewaters |
DE2553840C3 (en) * | 1975-11-29 | 1981-01-29 | Bayer Ag, 5090 Leverkusen | Pressure hydrolytic treatment of waste water |
US4119495A (en) * | 1977-01-21 | 1978-10-10 | Vasily Dmitrievich Belyaev | Method for processing activated sludge into useful products |
-
1977
- 1977-06-27 NL NL7707081A patent/NL7707081A/en not_active Application Discontinuation
-
1978
- 1978-06-20 US US05/917,359 patent/US4190528A/en not_active Expired - Lifetime
- 1978-06-21 IT IT49964/78A patent/IT1105452B/en active
- 1978-06-21 EP EP78200057A patent/EP0000230B1/en not_active Expired
- 1978-06-21 DE DE7878200057T patent/DE2860355D1/en not_active Expired
- 1978-06-23 JP JP7636578A patent/JPS5413664A/en active Pending
-
1979
- 1979-07-03 US US06/054,434 patent/US4240904A/en not_active Expired - Lifetime
Also Published As
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EP0000230A1 (en) | 1979-01-10 |
US4190528A (en) | 1980-02-26 |
JPS5413664A (en) | 1979-02-01 |
IT7849964A0 (en) | 1978-06-21 |
NL7707081A (en) | 1978-12-29 |
DE2860355D1 (en) | 1981-03-12 |
US4240904A (en) | 1980-12-23 |
IT1105452B (en) | 1985-11-04 |
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