EP0690944B1 - Procede pour le nettoyage et l'entretien de systemes de conduites de distribution d'eau potable - Google Patents
Procede pour le nettoyage et l'entretien de systemes de conduites de distribution d'eau potable Download PDFInfo
- Publication number
- EP0690944B1 EP0690944B1 EP94912283A EP94912283A EP0690944B1 EP 0690944 B1 EP0690944 B1 EP 0690944B1 EP 94912283 A EP94912283 A EP 94912283A EP 94912283 A EP94912283 A EP 94912283A EP 0690944 B1 EP0690944 B1 EP 0690944B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- scale
- acid
- pipe
- cleaning solution
- 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 - Lifetime
Links
- 238000004140 cleaning Methods 0.000 title claims abstract description 43
- 238000009826 distribution Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 29
- 239000003651 drinking water Substances 0.000 title claims abstract description 15
- 235000012206 bottled water Nutrition 0.000 title claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 53
- 239000013049 sediment Substances 0.000 claims abstract description 26
- 230000002378 acidificating effect Effects 0.000 claims abstract description 14
- 238000011010 flushing procedure Methods 0.000 claims abstract description 6
- 239000002253 acid Substances 0.000 claims description 25
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 claims description 18
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 16
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 13
- 239000000344 soap Substances 0.000 claims description 10
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 9
- 239000011707 mineral Substances 0.000 claims description 9
- 150000007524 organic acids Chemical class 0.000 claims description 9
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 8
- 229910021529 ammonia Inorganic materials 0.000 claims description 8
- 235000005985 organic acids Nutrition 0.000 claims description 7
- 239000002028 Biomass Substances 0.000 claims description 6
- 241000295146 Gallionellaceae Species 0.000 claims description 5
- 239000003112 inhibitor Substances 0.000 claims description 5
- 150000001412 amines Chemical class 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims description 4
- 239000002738 chelating agent Substances 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 150000007522 mineralic acids Chemical class 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 239000004094 surface-active agent Substances 0.000 claims description 3
- 239000000654 additive Substances 0.000 claims description 2
- 239000008235 industrial water Substances 0.000 claims description 2
- 238000007789 sealing Methods 0.000 claims description 2
- 235000020188 drinking water Nutrition 0.000 claims 1
- 238000005086 pumping Methods 0.000 claims 1
- 239000000243 solution Substances 0.000 description 46
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 12
- 229960004275 glycolic acid Drugs 0.000 description 8
- 150000007513 acids Chemical class 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 7
- 230000007797 corrosion Effects 0.000 description 7
- 239000007787 solid Substances 0.000 description 7
- -1 hydrochloric Chemical class 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 239000004615 ingredient Substances 0.000 description 3
- 238000009533 lab test Methods 0.000 description 3
- 238000004062 sedimentation Methods 0.000 description 3
- 229940048842 sodium xylenesulfonate Drugs 0.000 description 3
- QUCDWLYKDRVKMI-UHFFFAOYSA-M sodium;3,4-dimethylbenzenesulfonate Chemical compound [Na+].CC1=CC=C(S([O-])(=O)=O)C=C1C QUCDWLYKDRVKMI-UHFFFAOYSA-M 0.000 description 3
- 239000005711 Benzoic acid Substances 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 2
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 235000010233 benzoic acid Nutrition 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- JOXIMZWYDAKGHI-UHFFFAOYSA-N toluene-4-sulfonic acid Chemical compound CC1=CC=C(S(O)(=O)=O)C=C1 JOXIMZWYDAKGHI-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- ULUAUXLGCMPNKK-UHFFFAOYSA-N Sulfobutanedioic acid Chemical class OC(=O)CC(C(O)=O)S(O)(=O)=O ULUAUXLGCMPNKK-UHFFFAOYSA-N 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- VTYYLEPIZMXCLO-UHFFFAOYSA-L calcium carbonate Substances [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 150000001735 carboxylic acids Chemical group 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003995 emulsifying agent Substances 0.000 description 1
- 150000002191 fatty alcohols Chemical class 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000013505 freshwater Substances 0.000 description 1
- 231100000206 health hazard Toxicity 0.000 description 1
- 239000003752 hydrotrope Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000003973 irrigation Methods 0.000 description 1
- 230000002262 irrigation Effects 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- MGFYIUFZLHCRTH-UHFFFAOYSA-N nitrilotriacetic acid Chemical compound OC(=O)CN(CC(O)=O)CC(O)=O MGFYIUFZLHCRTH-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 150000003014 phosphoric acid esters Chemical class 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000003352 sequestering agent Substances 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 230000007928 solubilization Effects 0.000 description 1
- 238000005063 solubilization Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 235000000346 sugar Nutrition 0.000 description 1
- 150000008163 sugars Chemical class 0.000 description 1
- 150000003871 sulfonates Chemical class 0.000 description 1
- 239000012085 test solution Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
- B08B9/02—Cleaning pipes or tubes or systems of pipes or tubes
- B08B9/027—Cleaning the internal surfaces; Removal of blockages
- B08B9/032—Cleaning the internal surfaces; Removal of blockages by the mechanical action of a moving fluid, e.g. by flushing
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/02—Inorganic compounds
- C11D7/04—Water-soluble compounds
- C11D7/08—Acids
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/22—Organic compounds
- C11D7/26—Organic compounds containing oxygen
- C11D7/265—Carboxylic acids or salts thereof
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/22—Organic compounds
- C11D7/32—Organic compounds containing nitrogen
- C11D7/3218—Alkanolamines or alkanolimines
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
-
- E—FIXED CONSTRUCTIONS
- E03—WATER SUPPLY; SEWERAGE
- E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
- E03B7/00—Water main or service pipe systems
- E03B7/006—Arrangements or methods for cleaning or refurbishing water conduits
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D2111/00—Cleaning compositions characterised by the objects to be cleaned; Cleaning compositions characterised by non-standard cleaning or washing processes
- C11D2111/10—Objects to be cleaned
- C11D2111/14—Hard surfaces
- C11D2111/20—Industrial or commercial equipment, e.g. reactors, tubes or engines
Definitions
- scale and sedimentation will increase the possibility of corrosion in the water distribution pipe along with promoting the growth of organisms.
- the organisms also can be a health hazard, promoting corrosion and biomass which binds scale and sediment together and to the surfaces of the system. Corrosion will eventually lead to the leakage of the system and the necessity to replace the leaking section.
- a proper cleaning and maintenance program for water distribution systems will prevent decreased water flow capacity, corrosion and the necessity to replace the system or portions thereof.
- a simple and effective method for cleaning and maintaining these systems is needed.
- ES-A-533818 discloses a method for eliminating lime incrustations from domestic water supply installations which represents the prior art as referred to in the preamble to Claim 1.
- US-A-4025359 discloses an inhibited acid composition for cleaning water systems which has a reduced tendency to attack galvanized pipe or steel pipe.
- WO-A-92/20629 discloses soap compositions of carboxylic acids and amines useful in removal and prevention of scale containing calcium or magnesium carbonate, oxide or hydroxide.
- FR-A-2602571 discloses a method and apparatus for cleaning a conduit of a potable water distribution network in which pulses of fluid under pressure, such as water, are passed through the conduit.
- a method of cleaning a potable water distribution pipe system of scale comprises providing a reservoir for containing an aqueous cleaning solution for the removal of the scale, circulating the cleaning solution from the reservoir through a section of pipe in the system and returning the solution to the reservoir for the removal of the scale, characterised in that the aqueous cleaning solution is suitable for removal of scale associated with sulfate-reducing and iron bacteria consisting primarily of iron oxide, biomass and sediment from inside surfaces of the water distribution system, in that the section of pipe is an underground section of a distribution pipe system and in that the method includes sealing off the underground section for circulation for cleaning solution therethrough.
- This invention is directed to a method of cleaning and maintaining water distribution systems.
- Water systems having interior scale and sediment deposits are cleaned by introducing and circulating an effective amount of an aqueous treatment solution for a sufficient period of time which results in the solution, loosening and suspension of the undesired scale and sediment. Thereafter, the spent treating solution containing the dissolved or suspended scale and sediment is flushed from the water distribution system to provide a clean system with improved water flow and operation. Additionally, further flushing with high pressure water will also remove additional scale that had been loosened by the treating solution.
- the cleaning solution may be acidic, neutral or basic.
- mineral acids or organic acids, and mixtures thereof are employed as acidic treatment solutions.
- the acidic treatment solution may contain further additives such as inhibitors, chelating agents, penetrating and/or dispersing agents to assist in the removal of scale and sediment and to minimize any adverse effects on the pipes, valves, or other system surfaces due to the acids employed.
- This invention provides a simple, low cost and effective method of removing water scale and sediment from water distribution systems in order to maintain proper water flow, operation and to prevent corrosion of the system which would require the high cost and inconvenience of replacement.
- acidic treatment solutions found to be useful in practicing the method of this invention are aqueous solutions of mineral acids such as hydrochloric, nitric, phosphoric, polyphosphoric, hydrofluoric, boric, sulfuric, sulfurous, and the like.
- Aqueous solutions of mono-, di- and polybasic organic acids have also been found to be useful and include formic, acetic, propionic, citric, glycolic, lactic, tartaric, polyacrylic, succinic, p-toluenesulfonic, and the like.
- the useful treatment solutions may also be aqueous mixtures of the above mineral and organic acids.
- Alkaline, acid, or neutral cleaning solutions may also be employed, as indicated above, depending upon the type of scale that needs to be removed.
- Sequestering or chelating agents such as EDTA (ethylenediamine tetraacetic acid), NTA (nitrilotriacetic acid), and derivatives, i.e., basic alkali salts, and the like have also been found to be useful in the treatment solution in certain cases.
- the acidic treatment solution may also contain acid inhibitors which substantially reduce the acidic action on metal surfaces of the water distribution system, particularly valves, fire hydrants, etc., and these various inhibitors for acids have been well documented in the patent art. Typical, but not necessarily all inclusive, examples of acid inhibitors are disclosed in the following U.S.
- Patents 2,758,970; 2,807,585; 2,941,949; 3,077,454; 3,607,781; 3,668,137; 3,885,913; 4,089,795; 4,199,469; 4,310,435; 4,541,945; 4,554,090; 4,587,030; 4,614,600; 4,637,899; 4,670,186; 4,780,150 and 4,851,149 which are incorporated herein by reference.
- the treatment solution may also contain dispersing, penetrating or emulsifying agents to assist in the removal of the scale and sediment.
- These surface active agents may be anionic, cationic, nonionic or amphoteric as defined in the art.
- Compounds such as alkyl ether sulfates, alkyl or aryl sulfates, alkanolamines, ethoxylated alkanolamides, amine oxides, ammonium and alkali soaps, betaines, hydrotropes such as sodium aryl sulfonates; ethoxylated and propoxylated fatty alcohols and sugars, ethoxylated and propoxylated alkylphenols, sulfonates, phosphate esters, quarternaries, sulfosuccinates, and mixtures thereof, have been found to be useful in admixture with the acid treating solution.
- Fig. 1 is a schematic of a laboratory test system illustrating the method of this invention.
- Fig. 2 is a diagram of a field system for cleaning a potable water distribution system.
- a laboratory test system is shown to evaluate the removal of scale and sediment by acidic treating solutions from a test pipe sample taken from a water distribution system.
- This system includes a 56.8 L (15 gallon) acidic treating solution reservoir 5, submersible acidic treating solution circulation pump 6 rated at 4543 L/h (1200 gallons per hour) 2.54 cm (1") inlet transfer line 7, drain valve 8, heavy rubber diaphragm seals 9 for the ends of the test pipe specimen 10, 2.54 cm (1") outlet transfer line 11 and the treating solution 12.
- the test pipe specimen 10 is mounted at about a 30 degree angle so that the test solution will contact essentially the entire inner pipe surface to be treated.
- the scale on the inside of the pipe consisted of nodules of up to 2.5 to 3.8 cm (1 to 11 ⁇ 2 inches) in height covering 100% of the inside pipe surface which had substantially reduced the opening inside the pipe for water to flow.
- FIG. 2 a field equipment and system diagram is shown which may be employed in the cleaning of a potable water pipe distribution system.
- Two 1.89 kl (500 gallon) treating solution reservoir tanks 20 and 21 along with a 6.3 L/s (100 gallon per minute) circulation pump 22 and sight glass 23 are mounted on a flat bed truck (not shown).
- a 6.4 cm (21 ⁇ 2) inlet pipe 24 is secured to a 198 m (650 foot) section of 15.2 cm (6") water distribution pipe 25 after the main shut off valve 26.
- the fire hydrant 27 and fire hose 28 were employed for the acidic treating solution return to tanks 20 and 21.
- the section of pipe 25 to be treated was isolated by closing off the two water main shut-off valves 26 and 29 along with all service line valves, typically 30 and 31. With valves 32 and 33 closed, 3785 L (1000 gallons) of acidic treating solution was prepared in tanks 20 and 21. With the coupling 34 open, the treating solution was allowed to enter the system by opening valves 33 and 35 and turning on the circulation pump 22. The pH of the water coming from the open coupling was then monitored until a decrease was noted which indicated the acid treating solution had displaced the water in the section to be treated. The circulation pump 22 was turned off and the coupling 34 connected. Valves 36 and 37 were then closed and valve 32 opened for circulation. The circulation pump 22 was then started again for the treatment period. Valve 37 was closed to allow for scale solids to accumulate in tank 20 while the treating solution could overflow at 38 to tank 21 which reduces the chances of plugging during treatment.
- the treating solution was then circulated in the system of Fig. 2 for a period of 5 hours. Observation of the treating solution through the sight glass 23 showed an increasingly darker discoloration with time.
- the circulation pump 22 was turned off, and valves 33 and 35 were closed.
- the main shut-off valve 26 was slowly opened and fresh water allowed to enter the system until the treating solution was displaced as noted when the tanks 20 and 21 were full. Valve 32 was then closed.
- the fire hose 28 was then disconnected from the fire hydrant 27 and the main shut-off valve 26 opened full to allow high pressure flushing of the treated water main 25. As the flush water emerged from the fire hydrant 27 it was dark in color with considerable scale and sediment solids. Flushing continued until the flush water was clean of solids for a period of time prior to putting the treated section of the water distribution system back into service.
- the flow rate through the fire hydrant 27 prior to treatment had been determined by a Pitot Gauge to be 588 gallons per minute. After treatment, the flow rate was determined to be 790 gallons per minute. This was an increase of 34.5%.
- cleaning solutions may be employed as follows: Preblend Ingredients % by wt 31% Hydrochloric acid in water 87.14 +/- 2% 70% Glycolic acid in water 5.27 +/- 0.3% 40% Sodium xylene sulfonate in water 2.06 +/- 0.2% Triethanolamine and diethanolamine mixture (85%/15%) 2.96 +/- 0.2% Water 2.57 +/- 0.2%
- the above preblended cleaning solution is used in an amount of about 12.5% by weight with water in the field for cleaning an underground potable water distribution pipe system.
- the solution may be employed in amounts of from about 5 to about 50% by weight with water in the field, depending upon such variables as the amount of scale, pipe volume to be cleaned, circulation time and other factors.
- the amounts of anhydrous chemicals in a broader range of ingredients are about 1% to 27% HCl, 0.1% to 4% glycolic acid, 0.04% to 1% sodium xylene sulfonate and about 0.1% to 2.5 % of the triethanolamine/diethanolomine mixture (hereinafter referred to as "TEA").
- hydrochloric acid may be added to a concentrate of the glycolic acid, sodium xylene sulfonate and TEA.
- an underground section of the pipe to be cleaned is sealed off from the rest of the system.
- the cleaning solution is then introduced from a tank into the pipe section and, if water is in that section of pipe, it is removed upon the introduction of the cleaning solution.
- circulation of the cleaning solution through the underground pipe is initiated for a sufficient period of time for solubilization, loosening and/or suspension of the scale and sediments.
- a soap having a 1:1 stoichiometric equivalent of the acid (HCl and glycolic acid) and TEA base is formed with an excess of the acid.
- This composition has been found to work effectively in the field for the removal of scale associated with sulfate-reducing and iron bacteria consisting primarily of iron oxide, biomass and sediment.
- These 1:1 soaps have also been described in the above referred to co-pending Application WO92/20629 and the disclosure thereof is incorporated herein in its entirety by reference.
- These soaps may be more generally categorized as soaps of mineral and/or organic acids and a base such as an amine and ammonia.
- soaps include 1:1 soaps of TEA and glycolic acid (also known as hydroxyacetic acid); TEA and acetic acid; TEA and citric acid; TEA and benzoic acid; hydrochloric acid and ammonia; sulfuric acid and ammonia; nitric acid and ammonia; TEA and hydrochloric acid; TEA and sulfuric acid; TEA and nitric acid; ammonia and glycolic acid; ammonia and benzoic acid; and ammonia and p-toluenesulfonic acid.
- TEA and glycolic acid also known as hydroxyacetic acid
- TEA and acetic acid also known as hydroxyacetic acid
- TEA and citric acid TEA and benzoic acid
- hydrochloric acid and ammonia sulfuric acid and ammonia; nitric acid and ammonia
- TEA and hydrochloric acid TEA and sulfuric acid
- TEA and nitric acid ammonia
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Wood Science & Technology (AREA)
- Health & Medical Sciences (AREA)
- Mechanical Engineering (AREA)
- Emergency Medicine (AREA)
- Inorganic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Hydrology & Water Resources (AREA)
- Public Health (AREA)
- Water Supply & Treatment (AREA)
- Cleaning In General (AREA)
- Cleaning By Liquid Or Steam (AREA)
- Detergent Compositions (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Processing Of Solid Wastes (AREA)
Claims (14)
- Procédé pour débarrasser du tartre un circuit de distribution d'eau potable comprenant les étapes consistant à :mettre en place un réservoir (20, 21) destiné à contenir une solution aqueuse de nettoyage pour éliminer le tartre,faire passer cette solution du réservoir (20, 21) au circuit par un tronçon de tuyau (25) etfaire revenir la solution au réservoir (20, 21) pour éliminer le tartre,
- Procédé selon la revendication 1, dans lequel le tronçon de tuyau (25) est scellé entre deux bouches à incendie (27) et la solution de nettoyage est mise en circulation en reliant une de ces bouches (27) au réservoir (20, 21) pour pomper la solution de nettoyage par cette bouche.
- Procédé selon la revendication 1 ou la revendication 2, comprenant le rinçage du circuit à l'eau pure après élimination de la solution de nettoyage usée.
- Procédé selon l'une quelconque des revendications précédentes, comprenant le rinçage du circuit avec une eau sous haute pression pour éliminer toute solution de nettoyage usée, tout tartre et/ou sédiment.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel la solution aqueuse de traitement est acide.
- Procédé selon la revendication 5, dans lequel la solution acide contient en outre des additifs choisis dans le groupe composé d'inhibiteurs de l'acide, d'agents de chélation, d'agents de pénétration et d'agents de dispersion et de leurs mélanges pour faciliter l'élimination du tarte et des sédiments.
- Procédé selon la revendication 5 ou la revendication 6, dans lequel l'acide est choisi dans le groupe composé des acides minéraux et organiques et de leurs mélanges.
- Procédé selon la revendication 7, dans lequel l'acide minéral et choisi dans le groupe composé des acides chlorhydrique, nitrique, phosphorique, polyphosphorique, hydrofluorique, borique, sulfurique et sulfureux et de leurs mélanges.
- Procédé selon la revendication 7 ou la revendication 8, dans lequel l'acide organique est choisi dans le groupe composé des acides formique, acétique, propionique, citrique, glycolique, lactique, tartrique, polyacrylique, succinique, p-toluène-sulfonique et leurs mélanges.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel la solution de nettoyage est un mélange d'acide chlorhydrique, d'acide glycolique, d'une alcanolamine et d'un surfactant.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel la solution de nettoyage comprend un savon ayant un acide et une base dans des proportions stoechiométriques équivalentes de 1:1, l'acide est choisi dans le groupe composé d'un acide minéral et d'un acide organique et la base choisie dans un groupe composé d'une amine et d'ammoniaque, une quantité suffisante d'acide libre se trouve en solution pour réagir avec le tartre.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel le réservoir est placé sur un camion pour constituer, stocker et éliminer la solution de nettoyage.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel le circuit de distribution est un système domestique ou industriel d'alimentation en eau.
- Procédé selon l'une quelconque des revendications précédentes, dans lequel la solution aqueuse de traitement répond aux normes imposées par le US National Sanitation Foundation Standard 60 pour les produits chimiques de traitement de l'eau potable utilisés dans les circuits de distribution de cette eau.
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US36188 | 1993-03-23 | ||
US08/036,188 US5360488A (en) | 1993-03-23 | 1993-03-23 | Method of cleaning and maintaining water distribution pipe systems |
US20995394A | 1994-03-17 | 1994-03-17 | |
US209953 | 1994-03-17 | ||
PCT/US1994/003065 WO1994021865A1 (fr) | 1993-03-23 | 1994-03-22 | Procede pour le nettoyage et l'entretien de systemes de conduites de distribution d'eau potable |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0690944A1 EP0690944A1 (fr) | 1996-01-10 |
EP0690944B1 true EP0690944B1 (fr) | 1998-09-02 |
Family
ID=26712917
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP94912283A Expired - Lifetime EP0690944B1 (fr) | 1993-03-23 | 1994-03-22 | Procede pour le nettoyage et l'entretien de systemes de conduites de distribution d'eau potable |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0690944B1 (fr) |
JP (1) | JP3597193B2 (fr) |
AT (1) | ATE170583T1 (fr) |
AU (1) | AU673426B2 (fr) |
BR (1) | BR9406139A (fr) |
CA (1) | CA2157916C (fr) |
DE (1) | DE69413017T2 (fr) |
WO (1) | WO1994021865A1 (fr) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0766765A1 (fr) * | 1994-06-20 | 1997-04-09 | H.E.R.C. Products Incorporated | Procede de nettoyage et d'entretien de systemes de conduites de distribution d'eau potable au moyen d'une solution de nettoyage chauffee |
US5755155A (en) * | 1997-02-28 | 1998-05-26 | Tetra Laval Holdings & Finance S.A. | Aseptic process interface group |
JPH11141713A (ja) * | 1997-09-05 | 1999-05-28 | Tetra Laval Holdings & Finance Sa | 無菌弁組立体 |
JP2002052322A (ja) * | 2000-08-10 | 2002-02-19 | Kurita Water Ind Ltd | 洗浄方法 |
JP4283098B2 (ja) * | 2003-12-04 | 2009-06-24 | 花王株式会社 | 金属成分の処理液 |
JP5200326B2 (ja) * | 2006-03-30 | 2013-06-05 | 栗田工業株式会社 | スケール洗浄剤及びスケール除去方法 |
WO2016068525A1 (fr) * | 2014-10-27 | 2016-05-06 | 이기원 | Procédé pour enlever des incrustations |
RU2594426C1 (ru) * | 2015-02-26 | 2016-08-20 | Акционерное общество "Научно-исследовательский и проектный институт по переработке газа" (АО "НИПИгазпереработка") | Способ очистки внутренней поверхности технологического оборудования и трубопроводов (варианты) |
CA2969174A1 (fr) | 2017-06-02 | 2018-12-02 | Fluid Energy Group Ltd. | Compositions d'acide modifie novatrices comme remplacements des acides conventionnels dans l'industrie du petrole et du gaz |
DE202019003089U1 (de) * | 2019-07-24 | 2020-10-27 | Josef Schallameier | Entkalkung von unter Druck stehenden Rohrleitungen beliebiger Länge |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3667487A (en) * | 1970-12-11 | 1972-06-06 | Richardson Chem Cleaning Servi | Integrated chemical cleaning apparatus |
US4025359A (en) * | 1974-04-01 | 1977-05-24 | Connelly Jr George F | Inhibited acid composition for cleaning water systems |
EP0027980B1 (fr) * | 1979-10-24 | 1984-01-25 | Georg Fischer Aktiengesellschaft | Procédé et installation pour rincer, nettoyer, désinfecter et pour le revêtement intérieur d'une conduite, en particulier une conduite d'eau dans une nouvelle construction |
DE3244443C2 (de) * | 1982-12-01 | 1986-11-06 | Späne, Rainer, 7888 Rheinfelden | Verfahren zur Entfernung von eisen-, calcium- und manganhaltigen Verockerungen und/oder Versinterungen aus zur Wasserversorgung betriebenen Einrichtungen |
DE3583586D1 (de) * | 1984-11-30 | 1991-08-29 | Feldmann Chemie Gmbh | Verwendung von mischung aus organischen und/oder anorganischen saeuren und/oder sauren salzen zur entfernung von eisen- und manganhaltigen ablagerungen und verockerungen. |
FR2602571B1 (fr) * | 1986-08-06 | 1989-02-03 | Assainissement Rationnel Pompa | Procede de nettoyage d'une conduite notamment d'un reseau de distribution d'eau potable et systeme pour la mise en oeuvre de ce procede |
DE3631459A1 (de) * | 1986-09-16 | 1988-03-24 | Wegener Paul | Verfahren zum innenreinigen von verzweigten rohrleitungen und/oder aggregaten sowie vorrichtung zur durchfuehrung dieses verfahrens |
DE3731441A1 (de) * | 1987-08-13 | 1989-02-23 | Imhof Elisabeth | Verfahren und vorrichtung zur reinigung, korrosionsbeseitigung, ggf. entkalkung und versiegelung von gebaeudewasserinstallationen |
DE3828229A1 (de) * | 1988-08-19 | 1990-02-22 | Feldmann Chemie Gmbh | Mittel zur reinigung, desinfektion und wartung von trinkwasseranlagen und anlagen der getraenkeindustrie |
DE4015201A1 (de) * | 1990-05-11 | 1991-11-14 | Heimo Wessollek | Reiniger fuer trinkwasseranlagen |
DE4015202A1 (de) * | 1990-05-11 | 1991-11-14 | Heimo Wessollek | Reiniger fuer trinkwasseranlagen |
US5322635A (en) * | 1991-05-16 | 1994-06-21 | H.E.R.C. Incorporated | Soap compositions of carboxylic acids and amines useful in removal and prevention of scale |
DE4125315C2 (de) * | 1991-07-31 | 1995-09-28 | Oertzen Arndt H Gmbh & Co | Vorrichtung zum Reinigen von Rohrleitungen |
-
1994
- 1994-03-22 CA CA002157916A patent/CA2157916C/fr not_active Expired - Fee Related
- 1994-03-22 AU AU64903/94A patent/AU673426B2/en not_active Ceased
- 1994-03-22 BR BR9406139A patent/BR9406139A/pt not_active IP Right Cessation
- 1994-03-22 WO PCT/US1994/003065 patent/WO1994021865A1/fr active IP Right Grant
- 1994-03-22 AT AT94912283T patent/ATE170583T1/de active
- 1994-03-22 EP EP94912283A patent/EP0690944B1/fr not_active Expired - Lifetime
- 1994-03-22 JP JP52131394A patent/JP3597193B2/ja not_active Expired - Fee Related
- 1994-03-22 DE DE69413017T patent/DE69413017T2/de not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
CA2157916A1 (fr) | 1994-09-29 |
BR9406139A (pt) | 1996-01-30 |
CA2157916C (fr) | 2000-01-25 |
DE69413017D1 (de) | 1998-10-08 |
AU6490394A (en) | 1994-10-11 |
AU673426B2 (en) | 1996-11-07 |
ATE170583T1 (de) | 1998-09-15 |
WO1994021865A1 (fr) | 1994-09-29 |
DE69413017T2 (de) | 1999-01-28 |
JP3597193B2 (ja) | 2004-12-02 |
JPH08509908A (ja) | 1996-10-22 |
EP0690944A1 (fr) | 1996-01-10 |
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