GB2198049A - Process for the decrease in or complete removal of the water content of heat-sensitive liquid materials - Google Patents
Process for the decrease in or complete removal of the water content of heat-sensitive liquid materials Download PDFInfo
- Publication number
- GB2198049A GB2198049A GB08728076A GB8728076A GB2198049A GB 2198049 A GB2198049 A GB 2198049A GB 08728076 A GB08728076 A GB 08728076A GB 8728076 A GB8728076 A GB 8728076A GB 2198049 A GB2198049 A GB 2198049A
- Authority
- GB
- United Kingdom
- Prior art keywords
- mass
- water content
- temperature
- heat
- tray
- 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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D1/00—Evaporating
- B01D1/14—Evaporating with heated gases or vapours or liquids in contact with the liquid
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/18—Nitrates of ammonium
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Water Treatment By Sorption (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Gas Separation By Absorption (AREA)
Description
2198Inj A 9 1 j PROCESS FOR THE DECREASE IN OR COMPLETE REMOVAL OF THE
WATER CONTENT OF HEAT-SENSITIVE, LIQUID MATERIALS The invention relates to a novel process for the decrease in or a complete removal of the water content of heat-sensitive liquid materials such as melts or solutions containing at most 10 % by mass of water, by evaporating them at a temperature of at most 30 OC higher than that of the melting point of the melt or the temperature of crystal precipitation from the solution.
In case of the known processes serving for lo sLmil2r purposes, the residual water ccntent of melts and sclutions was removed ty evaporation under vacuum or by film evaporation (A.G. Kasatkin: Basic Operations, Machines and EquIpments of the Chemical Industry (in Hungarian), 3rd Edition, MUszaki Kiad6, Budapest, 1976, Chapter IX).
The use of vacuum evaporation is limited by the fact that the heat amount required to evaporate the w3ter content has to be transferred to the liquid system at a temperature as high as to cause a harmful, eventually irreersible decomposition of the material to be evaporated or even to eventually lead to an explosion. Furthermore, this method has a very high power demand since. in addition to the heat amount required to evaporate 2 - the water content, power (electric current, steam, cooling water) is also necessitated for establishing vacuum.
In case of film evaporation, a better utilization of the heat transferred to the liquid material is thereby achieved that in the film evaporator the hot melt or solution is contacted on a large surface (on the total surface of the pipes of the evaporator) with Lhe medium. taking up the Water content, i.e. with a relatively large amount of preheated ai.r. In this method tne principle of countercurrent direct contact is utilized to rer-,Dve the water content but, in adLition to tne evaporation heat Of the water ccntent to be removed, a surplus powc-7 is re--,..ired tO r_1.3Ve and p:eheat a la:, ge amount of air.
The aim of the present invention is to develop a process proiding the decrease in or the complete removal of the water content of heatsensitive, liquid materials at a low temperature and with a low power der-,,,and, by eliminating the drawl-jacks of the known processes.
The invention is based on the recognition that the above aim can completely be achieved by introducing the liquid material to a stripper tray column and leading a countercurrent gas through the column at a rate between 25 cr. sec -1 and 110 cm sec- 1 as calculated for the tctal cross section. In this case, the actual flow rate through the opening of the trays will be 6 to 25 m sec -1 - 3 as a consequence of the much lower free cross section.
Namely, it has been stated in the course of our experiments that by using the given rate of gas flow, the trays of the stripper column operate as a foam column and thus, owing to the fact that the contact surface between liquid and gas is maximum in a foam column, the desired effect of evaporation can be achieved by using an extraordinarily low amount of stripping gas, the latter amount being at least by an order of magnitude lower than that used in film evaporators, whereby the power udemand becomes much lower.
Thus, the present invention relates to a new process for the decrease in or a complete removal of the water c--ntent of he;-nt-sensiti..,,.e liquid materials such as melts or solutions containing at most 10 % by mass of w"er, by evaporating them at a temperature of at most a IL, 30 OC higher than that of the melting point of the melt or the temperature of crystal precipitation from the solution. The process of the invention comprises carrying out the evaporation in a stripper tray column, through which a countercurrent gas is led at a rate between 25 cm sec- 1 and 110 cm sec-'. It is suitable to use air as gas.
The column used in the process of the invention is known as equipment of the chemical industry since a long time (see e.g. A. G. Kasatkin, as cited above, p. 477) and is used as an adsDrber in several sectors of the chemical industry. It is frequently used as a - 4 desorber or distilling column; however, its use as an evaporat3r is fully novel.
The advantage of using a stripper column operating as a foam column is substantially provided by the 5great contact surface between the two phases since the equilibrium conditions belonging to the given pressure, temperature and concentration can be achieved at a much higher ef f iciency than by using a smaller conitaclting srj"ace. supposing '.'e same residence times. It can clearly be 2ppreE.Jate,- that a much greater contact eLrf ace is formed in the lloar, layer filled with fine bubbles tMan is cr-, the pipe surfaces of f i!.m ev,apor@to7s t -r USEd Li 11.r, the separatz.- of vacuL;, evaprat j:,s 07-, USinC a f -J-1r- E @PC-IBtOr Wit". 2_ Gl'P-2 Of 1 -13 Nr-. 3 h_l Gperating a Ica cf air are required. Fcr cc!-ur7-, with the saime output, 500 Nm 3 h-' of air are satisfying, i.e. in the process of the invention, the air derriand is cne- l,ventieth of the air a.Tcu-,it required for a fili- evapc7ator. Thus', the work of trans-fe:- anc the power derriand for heating the air amount are substantially reduced.
The adan'LageS Of the process of the invention can be sur,,,ma-.ized as follows:
a) The removal of the water content can be achj=-,ed in an equipment with smaller dimensions, i.e. b using less constrUCtiOn materials in plart roo, -s with less volume.
b) The cas can 'e reLIL;c:e:: at least ban e) order of magnitude in comparison to film evaporation.
C) The power demand of achieving the sarnne efficiency of evaporation and of preheating the gas are diminished.
d) The evaporation can be carried out with a higher safety. By the reduction of the gas amount used, less contaminated gas arises from the evaporation. Thus, lower expenses are required for purification than in case of film evaporaticn. The amount of materials getting into and contaminating the envircnment during ev2poration is reduced.
The process of the inventlon is illustrated in detail by the following non-limiting Examples.
Example_ 1
In a stripper evaporator column of 1.2 m in length and 0.5 m in diameter constructed from 304 L steel, the water content of an ammonium nitrate melt containing 98.5 % by mass of ammonium nitrate has to be reduced by approximately 1 % by mass. Two perforated bubbling trays and one heating tray are built into the column. The height of the weir is 10 cm. In 6 series on the heating tray, a pipe coil prepared from a pipe of 1 cm in diameter 2 is placed with a total heating surface of 2.8 rr.
10,000 kg of a r-,.elt containing 150 kg (1.5 % by mass) of water with a temperature of 170 0 C and with a solidification point of 151 0 C are hourly introduced into the colurrn.
500 Nrr, 3 of air with a temperature of 170 OC and with a pressure of 2.5 kP@ are blown into the column to achieve a linear flow rate of 65 cm sec1 as calculated for the total cross section.
The air bubIbling through the tray containing ammonium nitrate melt forms foam, whereby the water content of the melt leaving the tray is reduced to 0.78 by mass in such a way, that the heat amount required to the evaporation of the water content is covered by the sensible heat content of the melt. As a result, the relt cools to 16C 0 C, suppcsing that the 170 C C temperature f the iF,,tl-cd j 2jj. d-,e.s c,2-)ce d-.-.irg the operation.
-ceL L L 1 r-, crcjel- to f urthier concentrate the rrater i al the relt 1e2ing the lewer. tray with a tcr-,.;e-.ature c:r 160 0 C andwith a water content of 0.76%by rrass is lec through the heating tray and reheated to 170 0 C, then led tc the lower bubl--linl--4 tray where an air with the a,c),e paraT,,eters is blown through. Thus, the arFi,,,poniur, nitrate content of the melt increases to 99.48 % by mass while the temperature reaches 163 to 165 0 C. In most cases, e.g. for the production of fertilizers, this concentration satisfies the demands.
Example 2
An ammoniurr, nitrate solution with a concentration of 93 % by mass has to be concentrated to a water content -v 1 not higher than 0.5 % by mass. The diameter, construction material of the column used as well as the dimensions and construction of the trays are the same as described in Example 1 but the total length of Lhe column amounts to 2.5 m, the number of the built-in bubbling trays is 5 and that of the heating trays is 4. The ammonium nitrate solution is fed at a temperature of 160 OC to the upper perforated tray. The water content is removed by. using '150 Nm3 h-1 of air i 0 naing a te,-.iperature of 170 CC, an apparent flow rate of 100 cm sec-1 and a pressu-re of 10 kPa. The main characteristics of-the ma+.,-.!.-ial. flows cn the trays are as follows:
Tray 1, concentration: temperature:
Tray 2, concentration: temperature: concentration: temperature:
Tray 4, concentration: temperature:
Tray 5, concentration:. temperature:
Tray 3, A t inlet 93.0 by mass 160.0 c 95.2 by mass 170.0 c 97.1 by mass 170.0 C 98.4 by mass 170.0 0 c At outlet 95.2 % by mass 125.0 0 c 97.1 % by mass 140.0 CC 98.4 by mass 150.0 c 99.1 by mass 160.0 c 99.1 % by mass 99.5 by mass 170.0 0 c 164.0 0 c Thus, the final product of the evaporation is a melt with a water content of 0.5 % by mass andwith a temperature of 164 oc.
Example 3
An ammonium nitrate melt with a concentration of 98.7 % by mass is evaporated by using 300 Nm 3 h- 1 of air with a temperature of 170 0 C and a pressure of 1.2 kPa in the equipment described in Example 1. The apparent linear flow rate of the air in the column amounts to 40 cr-,, sec- 1.
The main characteristics of the material f lows cn trie trays are as follows:
At inlet At outlet Tray 1, ccncentration: tem.per a ture: Tray 2, concentration: temperature:
96.7 by mass 99.25 % by mass 170.0 C 162.0 0 C 99.25 % by mass 99.46 % by mass l-10.0 0 C 165.0 0 C Thus, the final product of the evaporation is a melt wi th a water content of 0.54 % by mass and with a temperature of 165 0 C.
Example A
The water content of a melt having a temperature of 150 0 C and containing 99.0 % by mass of urea has to be decreased to 0.1 % by mass in the column described 1 II in Example 1. For this purpose, 500 Nm 3 h-' of air with a temperature of 150 0 C and a pressure of 5 kPa are led through the column. The material cooling to 140 0 C on tray 1 is heated to 145 0 C on the middle heating tray and then carried to the evaporating tray 2. The main characteristics of the material flows on the trays are as follows:
At inlet At outlet Tray 1, concentration: 99.0 % by mass 99.7 % by mass temperature: 150.0 oc 140.0 0 C Tray 2, concentration: 99.7 % by mass 99.9 % by mass teimperature: 145.0 0 C 142.0 oc Thus, the final product of the evaporation is a urea melt with a water content of 0.1 % by mass and with a temperature of 142 0 C.
Example 5
The water content of a melt containing 99.5 k by mass of caprolactam and having a temperature of DC is removed in a column similar to that described, in Example 1, that is having the same length, construc tion material and arrangement of trays, but a diameter of only 0.4 m. 300 Nm 3 h- 1 of nitrogen having a temperature of 130 to 135 0 C and a pressure of 2 kPa are led through the column at a linear flow rate of 60 cm sec 1. The product leaving the Column has a temperature of 130 0 c and is practically water-free.
1
Claims (1)
- C 1 a i m S1. A process for the decrease in or a complete removal of the water content of heat-sensitive liquid materials such as melts or solutions containing at most 10 % by mass of water, by evaporating them at a 'ure of at most 30 0 C higher than that of the tem, p era 41. melting point of the melt or the temperature of crystal precipitation from the solution, which c o m p r i s e s carrying out the evaporation in a stripper tray column, through which a countercurrent gas is led at a rate 10 between 25 cm sec1 and 110 cm seC - 1.1. - A process as claimed in claim 1, whi ch c o m p r i S e S using air as gas.3. A process substantially as hereinbefore described in connection with any one of Examples 1 to 5.Published 1988 at The Patent Office, State House, 6671 High Holborn, London WCIR 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Crav. Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent. Con. 1/87.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| HU864972A HU199082B (en) | 1986-12-01 | 1986-12-01 | Method for decreasing or removing the moisture content of heat-sensitive melts |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8728076D0 GB8728076D0 (en) | 1988-01-06 |
| GB2198049A true GB2198049A (en) | 1988-06-08 |
| GB2198049B GB2198049B (en) | 1991-04-17 |
Family
ID=10969399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8728076A Expired - Fee Related GB2198049B (en) | 1986-12-01 | 1987-12-01 | Process for the decrease in or complete removal of the water content of heat-sensitive liquid materials |
Country Status (14)
| Country | Link |
|---|---|
| AT (1) | AT389056B (en) |
| BE (1) | BE1001727A3 (en) |
| CS (1) | CS270578B2 (en) |
| DD (1) | DD264617A5 (en) |
| DE (1) | DE3740717A1 (en) |
| FI (1) | FI875287L (en) |
| FR (1) | FR2607402B1 (en) |
| GB (1) | GB2198049B (en) |
| HU (1) | HU199082B (en) |
| IT (1) | IT1223396B (en) |
| NL (1) | NL8702878A (en) |
| NO (1) | NO168017C (en) |
| PL (1) | PL269163A1 (en) |
| SE (1) | SE8704794L (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107850395A (en) * | 2015-05-27 | 2018-03-27 | 新南创新私人有限公司 | The method for aiding in thermic change |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB380928A (en) * | 1930-09-08 | 1932-09-29 | Melle Usines Sa | Improvements relating to the continuous separation of a body from its solution in a liquid |
| GB435134A (en) * | 1934-03-19 | 1935-09-16 | Thermal Syndicate Ltd | Improvements in or relating to concentration or absorption towers |
| GB515025A (en) * | 1937-05-25 | 1939-11-23 | Melle Usines Sa | Improvements in or relating to dehydration by azeotropic distillation |
| GB2005146A (en) * | 1977-10-07 | 1979-04-19 | Goodyear Tire & Rubber | Separation apparatus and method |
| GB1547051A (en) * | 1976-04-03 | 1979-06-06 | Shinetsu Chemical Co | Removal of vinyl chloride from polymers |
| GB1601679A (en) * | 1977-12-30 | 1981-11-04 | Norsk Hydro As | Process for the reduction of the vinyl chloride content of aqueous dispersions of vinyl chloride polymers and copolymers |
| EP0055496A1 (en) * | 1980-12-31 | 1982-07-07 | Shell Internationale Researchmaatschappij B.V. | Method for removing vinyl chloride from an aqueous sluray of polyvinyl chloride particles |
| EP0070496A2 (en) * | 1981-07-20 | 1983-01-26 | Heinz Schumacher | Apparatus for the treatment of flaky or granulated material with gases or vapors in a continuous countercurrent process |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE332001A (en) * | 1925-02-07 | |||
| NL80636C (en) * | 1952-03-26 | |||
| GB805199A (en) * | 1956-01-31 | 1958-12-03 | Commercial Solvents Corp | Improvements in or relating to process of preparing dry ammonium nitrate |
| US4511431A (en) * | 1982-06-04 | 1985-04-16 | White Consolidated Industries, Inc. | Process for evaporative stripping |
-
1986
- 1986-12-01 HU HU864972A patent/HU199082B/en not_active IP Right Cessation
-
1987
- 1987-11-26 AT AT0310687A patent/AT389056B/en not_active IP Right Cessation
- 1987-12-01 GB GB8728076A patent/GB2198049B/en not_active Expired - Fee Related
- 1987-12-01 DD DD87309725A patent/DD264617A5/en not_active IP Right Cessation
- 1987-12-01 SE SE8704794A patent/SE8704794L/en not_active Application Discontinuation
- 1987-12-01 IT IT22826/87A patent/IT1223396B/en active
- 1987-12-01 NL NL8702878A patent/NL8702878A/en not_active Application Discontinuation
- 1987-12-01 NO NO875003A patent/NO168017C/en unknown
- 1987-12-01 DE DE19873740717 patent/DE3740717A1/en not_active Withdrawn
- 1987-12-01 FR FR878716621A patent/FR2607402B1/en not_active Expired - Fee Related
- 1987-12-01 CS CS878721A patent/CS270578B2/en unknown
- 1987-12-01 BE BE8701365A patent/BE1001727A3/en not_active IP Right Cessation
- 1987-12-01 PL PL26916387A patent/PL269163A1/en unknown
- 1987-12-01 FI FI875287A patent/FI875287L/en not_active Application Discontinuation
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB380928A (en) * | 1930-09-08 | 1932-09-29 | Melle Usines Sa | Improvements relating to the continuous separation of a body from its solution in a liquid |
| GB435134A (en) * | 1934-03-19 | 1935-09-16 | Thermal Syndicate Ltd | Improvements in or relating to concentration or absorption towers |
| GB515025A (en) * | 1937-05-25 | 1939-11-23 | Melle Usines Sa | Improvements in or relating to dehydration by azeotropic distillation |
| GB1547051A (en) * | 1976-04-03 | 1979-06-06 | Shinetsu Chemical Co | Removal of vinyl chloride from polymers |
| GB2005146A (en) * | 1977-10-07 | 1979-04-19 | Goodyear Tire & Rubber | Separation apparatus and method |
| GB1601679A (en) * | 1977-12-30 | 1981-11-04 | Norsk Hydro As | Process for the reduction of the vinyl chloride content of aqueous dispersions of vinyl chloride polymers and copolymers |
| EP0055496A1 (en) * | 1980-12-31 | 1982-07-07 | Shell Internationale Researchmaatschappij B.V. | Method for removing vinyl chloride from an aqueous sluray of polyvinyl chloride particles |
| EP0070496A2 (en) * | 1981-07-20 | 1983-01-26 | Heinz Schumacher | Apparatus for the treatment of flaky or granulated material with gases or vapors in a continuous countercurrent process |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107850395A (en) * | 2015-05-27 | 2018-03-27 | 新南创新私人有限公司 | The method for aiding in thermic change |
| EP3303963A4 (en) * | 2015-05-27 | 2018-12-19 | NewSouth Innovations Pty Limited | Method for assisting thermally-induced changes |
| CN107850395B (en) * | 2015-05-27 | 2020-06-23 | 新南创新私人有限公司 | Method for assisting thermally induced changes |
| US11198074B2 (en) | 2015-05-27 | 2021-12-14 | Newsouth Innovations Pty Limited | Method for assisting thermally-induced changes |
| AU2016267408B2 (en) * | 2015-05-27 | 2021-12-16 | Newsouth Innovations Pty Limited | Method for assisting thermally-induced changes |
Also Published As
| Publication number | Publication date |
|---|---|
| DD264617A5 (en) | 1989-02-08 |
| BE1001727A3 (en) | 1990-02-20 |
| GB8728076D0 (en) | 1988-01-06 |
| CS872187A2 (en) | 1989-11-14 |
| FR2607402A1 (en) | 1988-06-03 |
| NO168017B (en) | 1991-09-30 |
| HU199082B (en) | 1990-01-29 |
| NO875003L (en) | 1988-06-02 |
| NL8702878A (en) | 1988-07-01 |
| NO875003D0 (en) | 1987-12-01 |
| IT1223396B (en) | 1990-09-19 |
| SE8704794D0 (en) | 1987-12-01 |
| GB2198049B (en) | 1991-04-17 |
| AT389056B (en) | 1989-10-10 |
| PL269163A1 (en) | 1988-09-01 |
| FI875287A0 (en) | 1987-12-01 |
| ATA310687A (en) | 1989-03-15 |
| NO168017C (en) | 1992-01-08 |
| DE3740717A1 (en) | 1988-06-16 |
| FR2607402B1 (en) | 1991-08-30 |
| CS270578B2 (en) | 1990-07-12 |
| FI875287A7 (en) | 1988-06-02 |
| IT8722826A0 (en) | 1987-12-01 |
| HUT45606A (en) | 1988-07-28 |
| FI875287L (en) | 1988-06-02 |
| SE8704794L (en) | 1988-06-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| ES456038A1 (en) | Process and apparatus for removing vaporizable constituents from viscous solutions or melts of thermoplastics | |
| US5500189A (en) | Apparatus for crystallization of organic matter | |
| US4390398A (en) | Modified process for resin manufacturing using a continuous separate distillation column | |
| US3367847A (en) | Purification of ethylene glycol containing salts of terephthalic acid by plural distiallation | |
| US10138209B2 (en) | Process for purifying an ionic liquid | |
| US4014735A (en) | Concentration and separation of corrosive liquid mixtures | |
| US4197139A (en) | Process for the reclamation of acid from spent pickle liquor | |
| CA1152285A (en) | Process and apparatus for regenerating sulphuric acid | |
| US3933575A (en) | Separation of corrosive liquid mixtures | |
| US2764234A (en) | Method and apparatus for concentrating liquids | |
| WO1983001011A1 (en) | Liquid purification system | |
| US2124729A (en) | Concentrating acid solutions | |
| US4323431A (en) | Purification of compounds having high melting point | |
| US3713991A (en) | Recovery of dimethylformamide by crystallization and distillation | |
| US3411992A (en) | Distillation utilizing a vapor compressor and an immiscible liquidsolid medium | |
| US3109864A (en) | Oxidation of hydrocarbons | |
| GB2198049A (en) | Process for the decrease in or complete removal of the water content of heat-sensitive liquid materials | |
| US3865929A (en) | Hydrogen fluoride recovery process | |
| US4575403A (en) | Apparatus for distilling phosphorus | |
| US4072024A (en) | Recovery of ammonia from underground storage | |
| US4483746A (en) | Process for phosphorus purification | |
| US3893893A (en) | Apparatus for the recovery of trichlorethylene from oil waste | |
| GB2096124A (en) | Production of ammonium nitrate | |
| US3438420A (en) | Preparation of concentrated alkyllithium solutions | |
| US3254962A (en) | Apparatus for oxidizing hydrocarbons |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19921201 |