GB2113254A - Process for cleaning the jacket of a glass-lined reactor - Google Patents
Process for cleaning the jacket of a glass-lined reactor Download PDFInfo
- Publication number
- GB2113254A GB2113254A GB08301192A GB8301192A GB2113254A GB 2113254 A GB2113254 A GB 2113254A GB 08301192 A GB08301192 A GB 08301192A GB 8301192 A GB8301192 A GB 8301192A GB 2113254 A GB2113254 A GB 2113254A
- Authority
- GB
- United Kingdom
- Prior art keywords
- weight
- jacket
- chelant
- dispersant
- aqueous composition
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 18
- 238000004140 cleaning Methods 0.000 title claims description 14
- 239000000203 mixture Substances 0.000 claims abstract description 15
- 239000013522 chelant Substances 0.000 claims abstract description 12
- 239000002270 dispersing agent Substances 0.000 claims abstract description 12
- 229910052751 metal Inorganic materials 0.000 claims abstract description 10
- 239000002184 metal Substances 0.000 claims abstract description 10
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 claims abstract description 8
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000002518 antifoaming agent Substances 0.000 claims description 10
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 3
- 229920000151 polyglycol Polymers 0.000 claims description 3
- 239000010695 polyglycol Substances 0.000 claims description 3
- 229920005552 sodium lignosulfonate Polymers 0.000 claims description 2
- SONHXMAHPHADTF-UHFFFAOYSA-M sodium;2-methylprop-2-enoate Chemical compound [Na+].CC(=C)C([O-])=O SONHXMAHPHADTF-UHFFFAOYSA-M 0.000 claims 1
- 239000011521 glass Substances 0.000 abstract description 5
- 238000002161 passivation Methods 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 229910052742 iron Inorganic materials 0.000 description 5
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 4
- 239000011575 calcium Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- 229910052791 calcium Inorganic materials 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 2
- 235000010216 calcium carbonate Nutrition 0.000 description 2
- 229960001484 edetic acid Drugs 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 229920000193 polymethacrylate Polymers 0.000 description 2
- BAERPNBPLZWCES-UHFFFAOYSA-N (2-hydroxy-1-phosphonoethyl)phosphonic acid Chemical compound OCC(P(O)(O)=O)P(O)(O)=O BAERPNBPLZWCES-UHFFFAOYSA-N 0.000 description 1
- 229920001174 Diethylhydroxylamine Polymers 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- FVCOIAYSJZGECG-UHFFFAOYSA-N diethylhydroxylamine Chemical compound CCN(O)CC FVCOIAYSJZGECG-UHFFFAOYSA-N 0.000 description 1
- GRWZHXKQBITJKP-UHFFFAOYSA-L dithionite(2-) Chemical compound [O-]S(=O)S([O-])=O GRWZHXKQBITJKP-UHFFFAOYSA-L 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000002895 organic esters Chemical class 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- HERBOKBJKVUALN-UHFFFAOYSA-K trisodium;2-[bis(carboxylatomethyl)amino]acetate;hydrate Chemical compound O.[Na+].[Na+].[Na+].[O-]C(=O)CN(CC([O-])=O)CC([O-])=O HERBOKBJKVUALN-UHFFFAOYSA-K 0.000 description 1
- 238000004457 water analysis Methods 0.000 description 1
- -1 which is preferred Chemical compound 0.000 description 1
Classifications
-
- 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
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
-
- 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
- C23G1/14—Cleaning or pickling metallic material with solutions or molten salts with alkaline solutions
- C23G1/19—Iron or steel
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Environmental & Geological Engineering (AREA)
- Hydrology & Water Resources (AREA)
- Water Supply & Treatment (AREA)
- Life Sciences & Earth Sciences (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Detergent Compositions (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
The metal jacket of a glass-filled reactor is cleaned with an aqueous mix of chelant, e.g. ethylenediamine tetraacetic acid, dispersant, and metal passivator e.g. hydrazine in defined amounts. Enables scale removal and passivation of the metal parts without damaging the glass lining.
Description
SPECIFICATION
Process for cleaning the jacket of a glass-lined reactor
This invention is directed to cleaning the interior of the jacket of a glass-lined reactor, using a
cleaner especially formulated to remove scale and rust without, however, forming hydrogen, which tends to diffuse through the reactor wall and attack the glass lining inside the reactor.
Substantially any heating or cooling medium circulated through the jacket of a jacketed glass
lined reactor will gradually cause formation of rust and/or result in scale. These deposits interfere with heat transfer and require periodic removal. For such a purpose, acidic cleaners are probably the worst, for the reason above given. Alkaline cleaners have been used, but fail to remove hardness-type scale.
Hydrosulfite cleaners remove iron, but not hardness scale.
In the past, these reactors have been dismantled, sandblasted to remove the scale, and relined.
Such a relining requires from 14 to 1 6 weeks at a cost of approximately 70% of the original price of this reactor.
Therefore, a cleaning product that would effectively remove scale and passivate the metal parts while at the same time not damage the glass lining is needed.
We have now found, according to the present invention, that the disadvantages of prior art jacket cleaning processes can be avoided to a large extent by the use of a special aqueous cleaner comprising a chelant, a dispersant, a metal passivator, and (optionally) an antifoaming agent.
According to the present invention there is provided a method of cleaning the jacket of a giasslined reactor which comprises passing therethrough an aqueous composition which comprises, by weight, at least 0.05% of a chelant, at least 0.01% of a dispersant and at least 0.01% of a ferrous metal passivator. Optionally, an antifoaming agent is included in the composition.
The preferred chelant is ethylene diamine tetra acetic acid, but other chelants can be used, for example, trisodium nitrilotriacetate monohydrate.
Suitable antifoaming agents include polyglycols as well as antifoams based on organic esters.
Besides sodium lignosuifate and/or sodium polymethacrylate which are the preferred dispersants, others which are suitable include the organophosphates and hydroxy-ethylidene diphosphonic acid.
Suitable ferrous metal passivators include hydrazine, which is preferred, and diethylhydroxylamine.
Preferably, the chelant is present in an amount from 0.05 to 4, especially 0.5 to 4% by weight, the dispersant is present in an amount from 0.01 to 1.5, especially 0.01 to 0.55, % by weight, and the passivator is present in an amount from 0.01 to 4, especially 0.015 to 1.0, % by weight. Typically, if present, the antifoaming agent is present in an amount of at least 0.0001% by weight, for example from 0.0001 to 1.5% by weight, especially up to 0.0005% by weight.
In general, the composition is passed through the jacket at 120 to 1500 F for 4 to 8 hours.
Desirably the composition is passed through until its conductivity has increased by at least 50%.
It is generally convenient to provide the composition in the form of a concentrate which is diluted, for example about 1:10, with water at the time of use.
The following Example further illustrates the present invention.
Example 1
The jacket of a 1000 gallon glass-lined reactor had become filled with scale which had reduced the water flow and caused a reduction in heat transfer.
The cleaner (concentrate) comprises: Wt. % 38% aqueous solution of ethylene diamine tetra acetic acid (chelant and
cleaner) 98.625
Polyglycol (antifoaming agent) .005
Sodium lignosulfonate (dispersant) .16
Sodium polymethacrylate, 4500 mol wt (dispersant) .55
Hydrazine, 35% aqueous solution (metal passivator) .66
100.00
The cleaning procedure was as follows:
(1) Feed 1.1 parts of cleaner with 10 parts of city water (Rochester, New York) to the reactor
jacket.
(2) Circulate this solution at 120-1 500F (49-650C) for 4-8 hours.
(3) Drain the reactor jacket and measure the specific conductance of effluent against a standard
of 305 micromhos for the city water in this example. (305 micromhos was the conductivity
of the water before the addition of the chemical).
(4) Based on the conductivity reading, determine whether sufficient cleaning has taken place or
whether an additional charge of chemical is required. If the conductivity of the cleaning
solution has increased by at least 50% after recirculation, then sufficient cleaning will have
taken place.
The following Table shows the results of the chemical cleaning. The first column shows the analysis of the cleaning solution after chemical addition but before recirculation. The second analysis is that of the cleaning solution after 4 hours of recirculation. The changes in the total dissolved solids, the hardness of CaCO3, the calcium content, and the iron content should be noted. The total dissolved solids nearly doubled. The amount of hardness increased by more than six times. The iron increased eight-fold. All these measurements show that the scale that consisted largely of calcium and iron was being dissolved by the cleanser.
Water analysis
Cleaner plus city water
Before After
circulation circulation
Total dissolved solids, ppm 18,698 35,610
pH 11.9 12
Hardness as CaCO3 223 1,406
Specific conductance micromhos/cm 9,410 14,700
Calcium as Ca, ppm 76 546
Magnesium as Mg, ppm 80 10
Iron as Fe, ppm 8.6 8.0
Silica as 502 1 1.1
The cleaner used in this example is available commerically as Polymate 661 (a concentrate) from
Dearborn Chemical Co. In a more general sense, the following is suitable:
chelant 17.95-98.625 wt %
antifoaming agent 0-0.005 dispersant 0.1-5.5 metal passivator 0.5-3.0 water, to make 100%
Within the range given, more chelant can be used, depending on the severity of the scale.
Claims (14)
1. A method of cleaning the jacket of a glass-lined reactor which comprises passing therethrough an aqueous composition which comprises, by weight, at least 0.05% of a chelant, at least 0.01% of a dispersant and at least 0.01% of a ferrous metal passivator.
2. A method according to claim 1 in which the aqueous composition comprises at least 0.0001% by weight of an antifoaming agent.
3. A method according to claim 1 or 2 in which the aqueous composition comprises 0.05 to 4% by weight of chelant, 0.01 to 1.5% by weight of dispersant, 0.01 to 4% by weight of passivator and, optionally, 0.0001 to 1.5% by weight of antifoaming agent.
4. A method according to any one of claims 1 to 3 in which the aqueous composition contains 0.5 to 4% by weight of chelant.
5. A method according to any one of claims 1 to 4 in which the aqueous composition contains 0.015 to 0.1% by weight of passivator.
6. A method according to any one of claims 1 to 5 in which the aqueous composition contains 0.01 to 0.55% by weight of dispersant.
7. A method according to any one of claims 2 to 6 in which the aqueous composition contains up to 0.0005% by weight of antifoaming agent.
8. A method according to any one of claims 1 to 7 in which the chelant is ethylenediamine tetraacetic acid.
9. A method according to any one of claims 1 to 8 in which the dispersant is sodium lignosulphonate and/or sodium methacrylate.
10. A method according to any one of claims 1 to 9 in which the passivator is hydrazine.
11. A method according to any one of claims 2 to 10 in which the antifoaming agent is a polyglycol.
12. A method according to any one of the preceding claims in which the composition is passed through the jacket at 120 to 1 500 F for 4 to 8 hours.
13. A method according to any one of the preceding claims in which the composition is passed through the jacket until its conductivity has increased by at least 50%.
14. A method according to claim 1 substantially as hereinbefore described.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US34023182A | 1982-01-18 | 1982-01-18 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8301192D0 GB8301192D0 (en) | 1983-02-16 |
| GB2113254A true GB2113254A (en) | 1983-08-03 |
| GB2113254B GB2113254B (en) | 1985-09-11 |
Family
ID=23332438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08301192A Expired GB2113254B (en) | 1982-01-18 | 1983-01-17 | Process for cleaning the jacket of a glass-lined reactor |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS58123000A (en) |
| CA (1) | CA1199550A (en) |
| DE (1) | DE3232263A1 (en) |
| ES (1) | ES519043A0 (en) |
| FR (1) | FR2521159B1 (en) |
| GB (1) | GB2113254B (en) |
| IT (1) | IT1157343B (en) |
| SE (1) | SE8204843L (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0121631A3 (en) * | 1983-04-12 | 1986-05-14 | Chemed Corporation | Method of removing scale |
| US4708805A (en) * | 1986-11-24 | 1987-11-24 | Muhala Thomas F D | Barium sulfate removal and anti-deposition compositions and process of use therefor |
| US4726907A (en) * | 1983-08-10 | 1988-02-23 | Nuclear Technology Corp | Hydrazides of amino-polyacetic acids as chelants |
| EP0273182A1 (en) * | 1986-12-01 | 1988-07-06 | Siemens Aktiengesellschaft | Method of cleaning a container |
| US4775491A (en) * | 1983-08-10 | 1988-10-04 | Nuclear Technology Corp. | Hydrazides of amino-polyacetic acids as chelants |
| EP0299166A1 (en) * | 1987-07-17 | 1989-01-18 | Mitsubishi Jukogyo Kabushiki Kaisha | Method for removing scale on inner surfaces of boiler tube members |
| US5264041A (en) * | 1986-12-01 | 1993-11-23 | Siemens Aktiengesellschaft | Method for cleaning a vessel |
| WO1995030032A1 (en) * | 1994-05-02 | 1995-11-09 | United Technologies Corporation | Effective cleaning method for turbine airfoils |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9000028D0 (en) * | 1990-01-02 | 1990-03-07 | Shell Int Research | Cleaning of equipment used in a liquid phase oxidation process |
| JP2007020402A (en) * | 2005-07-12 | 2007-02-01 | Nitto Shokuhin Kk | Method for producing fermented soybean |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1076979A (en) * | 1963-08-13 | 1967-07-26 | William Russell Tedeschi | Surface treating composition |
| AT281541B (en) * | 1966-08-02 | 1970-05-25 | Beratherm Ag | Process for pickling metallic inner surfaces of closed vessels |
| US3522093A (en) * | 1967-02-27 | 1970-07-28 | Chem Cleaning & Equipment Serv | Processes of cleaning and passivating reactor equipment |
-
1982
- 1982-08-24 SE SE8204843A patent/SE8204843L/en unknown
- 1982-08-31 DE DE19823232263 patent/DE3232263A1/en not_active Withdrawn
- 1982-10-15 CA CA000413558A patent/CA1199550A/en not_active Expired
- 1982-11-12 JP JP57197870A patent/JPS58123000A/en active Pending
- 1982-12-14 IT IT24722/82A patent/IT1157343B/en active
-
1983
- 1983-01-17 ES ES519043A patent/ES519043A0/en active Granted
- 1983-01-17 GB GB08301192A patent/GB2113254B/en not_active Expired
- 1983-01-17 FR FR8300626A patent/FR2521159B1/en not_active Expired
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0121631A3 (en) * | 1983-04-12 | 1986-05-14 | Chemed Corporation | Method of removing scale |
| US4726907A (en) * | 1983-08-10 | 1988-02-23 | Nuclear Technology Corp | Hydrazides of amino-polyacetic acids as chelants |
| US4775491A (en) * | 1983-08-10 | 1988-10-04 | Nuclear Technology Corp. | Hydrazides of amino-polyacetic acids as chelants |
| US4708805A (en) * | 1986-11-24 | 1987-11-24 | Muhala Thomas F D | Barium sulfate removal and anti-deposition compositions and process of use therefor |
| EP0273182A1 (en) * | 1986-12-01 | 1988-07-06 | Siemens Aktiengesellschaft | Method of cleaning a container |
| US5164015A (en) * | 1986-12-01 | 1992-11-17 | Siemens Aktiengesellschaft | Method for cleaning a vessel |
| US5264041A (en) * | 1986-12-01 | 1993-11-23 | Siemens Aktiengesellschaft | Method for cleaning a vessel |
| EP0299166A1 (en) * | 1987-07-17 | 1989-01-18 | Mitsubishi Jukogyo Kabushiki Kaisha | Method for removing scale on inner surfaces of boiler tube members |
| WO1995030032A1 (en) * | 1994-05-02 | 1995-11-09 | United Technologies Corporation | Effective cleaning method for turbine airfoils |
Also Published As
| Publication number | Publication date |
|---|---|
| ES8402884A1 (en) | 1984-03-01 |
| FR2521159B1 (en) | 1987-04-03 |
| GB8301192D0 (en) | 1983-02-16 |
| SE8204843D0 (en) | 1982-08-24 |
| FR2521159A1 (en) | 1983-08-12 |
| GB2113254B (en) | 1985-09-11 |
| CA1199550A (en) | 1986-01-21 |
| IT1157343B (en) | 1987-02-11 |
| ES519043A0 (en) | 1984-03-01 |
| JPS58123000A (en) | 1983-07-21 |
| SE8204843L (en) | 1983-07-19 |
| DE3232263A1 (en) | 1983-07-28 |
| IT8224722A0 (en) | 1982-12-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |