AU623871B2 - Method and equipment for decomposition of nitroglycerine in the residual nitration acids - Google Patents
Method and equipment for decomposition of nitroglycerine in the residual nitration acids Download PDFInfo
- Publication number
- AU623871B2 AU623871B2 AU27403/88A AU2740388A AU623871B2 AU 623871 B2 AU623871 B2 AU 623871B2 AU 27403/88 A AU27403/88 A AU 27403/88A AU 2740388 A AU2740388 A AU 2740388A AU 623871 B2 AU623871 B2 AU 623871B2
- Authority
- AU
- Australia
- Prior art keywords
- residual acids
- nitroglycerine
- acids
- residual
- decomposition
- 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.)
- Ceased
Links
- 239000002253 acid Substances 0.000 title claims description 50
- 150000007513 acids Chemical class 0.000 title claims description 45
- SNIOPGDIGTZGOP-UHFFFAOYSA-N Nitroglycerin Chemical group [O-][N+](=O)OCC(O[N+]([O-])=O)CO[N+]([O-])=O SNIOPGDIGTZGOP-UHFFFAOYSA-N 0.000 title claims description 23
- 229960003711 glyceryl trinitrate Drugs 0.000 title claims description 23
- 238000000034 method Methods 0.000 title claims description 22
- 238000006396 nitration reaction Methods 0.000 title claims description 13
- 238000000354 decomposition reaction Methods 0.000 title claims description 12
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 17
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 14
- 235000011149 sulphuric acid Nutrition 0.000 claims description 14
- 239000001117 sulphuric acid Substances 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 238000010790 dilution Methods 0.000 claims description 9
- 239000012895 dilution Substances 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 9
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 7
- 235000011187 glycerol Nutrition 0.000 claims description 4
- 238000011437 continuous method Methods 0.000 claims 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 14
- 229910017604 nitric acid Inorganic materials 0.000 description 14
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000004821 distillation Methods 0.000 description 4
- 239000012429 reaction media Substances 0.000 description 4
- 238000007872 degassing Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000002360 explosive Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000013022 venting Methods 0.000 description 2
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 229910001369 Brass Inorganic materials 0.000 description 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical class [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000008246 gaseous mixture Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000005297 pyrex Substances 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000005185 salting out Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/12—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electromagnetic waves
- B01J19/122—Incoherent waves
- B01J19/126—Microwaves
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/90—Separation; Purification
- C01B17/94—Recovery from nitration acids
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/02—Preparation of esters of nitric acid
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
[7
AUSTRALIA
Forma PATENTS ACT 1952Le t-7 COMPLETE SPEC Z401q
(ORIGINAL)
FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: Complete Specification Lodged: Accepted: Lapsed: Published: Priority: Related Art: TIO BE COMPLETED BY APPLICANT *Name of Applicant: Address of Applicant: Actual Inventors: Address for Servrice: Complete Specification SOCIETE NATIONAL DES POUDRES ET EXPLOSIFS 12 Qual Henri IV, 75181 Paris Cedex 04, France MARC STEPHAN and JEAN-PIERRE CARTIER CALLINANS, Patent Attorneys, of 48-50 Bridge Road, Richmond 3121, Victoria, Australia.
for the invention entitled: "VMTOD AND EQIPPEN FOR DEY2CXVION OF NTROGLYCERINE IN THE RESIDUAL NITRATION~ ACTDS".
The following statement is a full description of this invention, including the best method of performing it known to us:nave tne patent assigned to it.
D let. for No-Convention 4. The basic application referred to in paragraph 2 of this Declaration was the first application made in a CGQ p 7 qr ntry in respect of the invention the subject of the Sa nliction.
2 The present invention relates to the method and equipment for decomposition of nitroglycerine in the residual nitration acids.
The manufacture of nitroglycerine which is effected in a .)ath for the nitration of glycerine necessitates the use of large volumes of nitric acid.
Only a small fraction of this acid is combined with the glycerine, with the greater part of the acid being eliminated in the form of effluent.
In addition to nitric acid, these effluents hereinafter referred to as "residual acids" also contain other compounds such as sulphuric acid and water, as well as a small quantity of nitroglycerine. The presence of too large an amount of water and of an explosive substance, namely nitroglycerine, in proportions varying generally between 2% and has the effect of rendering the effluent dangerous and not directly re-utilizable.
The effluent should therefore be treated to eliminate the explosive compound and possibly also to allow for separation of a0 0 the sulphuric acid and the nitric acid before recycling in the nitration procedure.
a i 9 t The object of the present invention is a method for the decomposition of the nitroglycerine contained in the residual acids derived from the nitration procedure, said method consisting of heat treatment of the residual acids by microwaves which allows for the separate recovery of the concentrated acids.
The decomposition of the nitroglycerine should be very rapid. The classical methods of treatment of the residual acids are based upon rapid heating of the reaction mixture by the direct injection of live steam into said mixture.
The French Patent No. 2 265 675 describes a method for eliminating nitrous oxides from a mixture containing, for example, nitric acid. Thi3 method consists of passing the residual acids through a de-nitrator, that is to say, through a device in which S 'I
A
3 they are subjected to entrainment in steam, preferably under vacuum. The main disadvantage of this de-ritrator is the dilution of the acid because, during the course of the operation of the entrainment in steam, the greater part of the water is condensed in the acid. It is therefore necessary to carry out dehydration in order to arrive at a concentration of acid which is re-usable.
It is known to persons skilled in the art that steam can be used to eliminate nitroglycerine from the residual acids from the nitration procedure. More precisely, the procedure is carried out in several stages. The first stage consists of adding water to the mixture at the point of discharge from the nitration plant in order to improve the solubility of the nitroglycerine and thus avoid the phenomenon of salting out. This stage which is called *444 "dilution" is very sensitive because it must be adapted to a number of parameters including the temperature.
9 4 e o a a a o oo 44f 2 0 0o e S6 ft D 44 4 i4 a a 4 11 4 t r I a *4 4 44 The mixture should then be stored in ballast tank(s) for safety reasons.
The residual acids are subsequently treated, for example, by counter-current in a distillation column which is supplied at the base with steam at a pressure between 5 and 7 bar in order to heat the residual acids to 140 150 °C and to bring about complete decomposition of the nitroglycerine by reaction with the nitric acid present in these residual acids. The overall formulation of this decomposition is generally considered to be as follows
CH
2 -O-NO2 CH -O-NO 2 5HNO 3 6N0 2 2NO 5H 2 0 2C0 2
CO
CH
2 -0-NO 2 This reaction, which is highly exothermic, evolves approximately 1600 Kcal/kg of nitroglycerine dissolved in the residual acids.
In addition to the distillation column, the equipment includes a condenser for the vaporized nitric acid and also a column for the absorption of the nitrogen oxides (NO and NO 2 produced in decomposition reaction which cannot be condensed.
ii 4 By starting out with residual acids having the following average composition: sulphuric acid 71% nitric acid 11% nitroglycerine water nitrogen oxides there is obtained from the base of the column, relatively dilute sulphuric acid (60 70% pure sulphuric acid), from the condenser, 80 85% pure nitric acid, *ano from the base of the absorption column, 50 55% pure nitric acid.
0 o The conventional procedure thus comprises a distillation of the residual acids which results in the separation of the sulphuric and nitric acids and the decomposition of the nitroglycerine.
This procedure is efficacious because the nitroglycerine is decomposed, but the injection of water into the reaction medium, on the one hand during the "dilution" stage and principally, as :steam, during the passage through the distillation column, causes rtt, a dilution of the sulphuric acid and this is a major disadvantage for its re-cycling. Actually, in order for the sulphuric acid to be re-utilizable in a sulphuric-nitric acid bath for nitration of glycerine, the concentration of the sulphuric acid needs to be raised from 60 70% up to a concentration equal to, or greater than, 95%. The stage of re-cycling of the sulphuric acid thus consumes large amounts of energy and is therefore very expensive.
The object of the present invention is to provide a method of treatment of the residual acids derived from the nitration bath which allows for recovery of concentrated acids which may be re-utilized directly or almost entirely.
1 1.._11 i The method in accordance with the present invention is defined by the following stages The first stage comprises the conventional step of dilution, that is to say, an addition of water or dilute sulphuric acid in variable proportions depending upon the operating conditions and particularly upon the external temperature. This step is intended to bring all the nitroglycerine into a homogenous phase in the residual acids and thus avoid the accumulation of nitroglycerine in a free form, saturated with acids which make it unstable.
The second stage comprises circulating the residual acids after U:oO dilution in equipment consisting of a circuit made up, in the U, direction of circulation of said acids, successively of an inlet for the residual acids after dilution, Uo, an external heating system using microwaves, EISo an exit for the mixture treated in this way, an exit for the nitrogen oxides.
A method in accordance with the present invention of implementing 0 o the procedure and putting into operation the equipment for decom- .UU. position of the nitroglycerine in the residual acids from the nitration, will now be described with reference to the functional S diagram shown in the single drawing.
The residual acids which have the composition shown on pageA, lines 3 7, are subjected to the dilution stage and are stored in one or more reservoir(s) 1 which are connected to a remote venting circuit to avoid the emission of nitrogen oxides in the proximity of the equipment and the operating personnel.
A metering pump 2 provides for supply of residual acids to the reactor 3 which consists of a feed pipe 4 and a degassing vessel made of Pyrex(RTM). The supply flow rate is 8.7 kg/hour. During the passage through the pipe 4, the residual acids are subjected to heating by microwaves. For this purpose, a microwave generator of 800 W capacity, furnished with a wave guide 7, is located at the level of said pipe. The wave guide, made of brass, has a rectangular cross-section 43 mm x 86 mm and is connected by means N 6 of a flange to the exit from the microwave generator and to the reaction medium by way of a variable piston. It is traversed by the feed pipe 4. The action of the microwaves allows for heating the residual acids to a temperature in the range from 110 °C to 130 preferably close to 120 'C at which temperature the reaction CH -O-NO 2 CH -0-NO 2 5HNO 3 6NO 2 2NO 5H20 2C02 CO CH -0-NO2 is initiated. This highly exothermic reaction raises the temperature of the medium to a value between 140 °C and 160 depending upon the delivery rate of the metering pump 2.
o 0 The decomposition of the nitroglycerine is apparent from the change in colour of the reaction medium. The untreated residual acids are green (at a temperature below 140 and they become yellow after treatment (at a temperature above 150 0
C).
The degassing vessel 5 which receives the residual acids immediately after they have been subjected to the action of the microo waves is furnished with the following equipment at the base an inlet for the residual acids in the course of the treatment, in the central region a discharge pipe to drain off the residual acids which contain practically nothing but sulphuric acid, said pipe being connected to a receptacle 10 by a pipeline, in the upper region a discharge pipe 11 for the nitrogen oxides evolved during the boiling of the reaction medium.
The sulphuric acid obtained has a concentration higher than so that it can be used directly in a nitration bath.
According to a conventional method, a portion of the gaseous mixture derived from the boiling of the residual acids is subsequently partially condensed by cooling to form nitric acid. For this purpose, a heat exchanger 13, for example a glass coil with water flowing through it, is attached to the discharge pipe 11 from the degassing vessel 5. A receptacle 12 is used to collect ii 7 the nitric acid. The vapours which are not condensed in the heat exchanger 13 that is to say the oxides of nitrogen (NO, NO 2 traces of nitric acid, as well as carbon monoxide and dioxide, produced by the decomposition of the nitroglycerine, are introduced into the base of an absorption column 14 where they flow counter-current to a stream of water. The nitric acid recovered Sat the base of the absorption column is collected in a reservoir i' 15, whereas the vapours which are not absorbed are eliminated by venting from the top of the column.
In accordance with a preferred embodiment of the invention, the residual acids may be preheated to an intermediate temperature 0i between the temperature of storage and the temperature of decomposition of the nitroglycerine. For safety reasons, this OC temperature must not be higher than 110 °C and should preferably 15 lower than or equal to 80 0 C. In the operational mode depicted in the drawing, this intermediate temperature is reached by the So e use of a heater 16 which is mounted between the metering pump 2 and the pipe 4 and which is supplied in co-current or countero current with the residual acids, which have been treated and heated, through pipeline 9 attached to the overflow outlet of the o o4 reactor vessel This allows for heat exchange to take place to raise the temp- 1 erature of the residual acids flowing in from the reservoir(s) ri 1 from 14 °C to 55-57 °C.
4*
Claims (5)
1. Continuous method for the decomposition of the nitroglycerine contained in the residual acids derived from the nitration of glycerine, comprising the addition of water or dilute sulphuric acid, to improve the solubility of the nitroglycerine, and circulation of said residual acids in equipment consisting of a circuit made up, in the direction of circulation of said acids, successively of an inlet for the residual acids after dilution by the addition of water or dilute sulphuric acid, an external system for heating the residual acids, an exit for the mixture treated in this way and an exit for the nitrogen oxides, wherein the external system of heating is a microwave system.
2. The method according to Claim 1, wherein the percentage of nitroglycerine in said residual acids is at the most equal to 3% by volume.
3. The method according to Claim 1 or 2, wherein said residual acids are raised to a temperature in the range from 110 °C to 130 preferable close i 15 to 120 by the action of microwaves.
4. The method according to Claims 1 to 3, wherein said residual acids are preheated to a temperature between 15 'C and 80 'C before being subjected II to the action of the microwaves. jI
5. The method according to Claim 4, wherein said residual acids are preheated by heat exchange with the treated residual acids. D A T E D this 11th day of March 1992. SOCIETE NATIONALE DES POUDRES ET EXPLOSIFS By its Patent Trade Mark Attorneys: CALLINAN LAWRIE I N1fV
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8718033 | 1987-12-23 | ||
| FR8718033A FR2625193B1 (en) | 1987-12-23 | 1987-12-23 | PROCESS AND PLANT FOR DEGRADATION OF NITROGLYCERIN IN NITRATION RESIDUAL ACIDS |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2740388A AU2740388A (en) | 1989-06-29 |
| AU623871B2 true AU623871B2 (en) | 1992-05-28 |
Family
ID=9358226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU27403/88A Ceased AU623871B2 (en) | 1987-12-23 | 1988-12-23 | Method and equipment for decomposition of nitroglycerine in the residual nitration acids |
Country Status (6)
| Country | Link |
|---|---|
| AU (1) | AU623871B2 (en) |
| CH (1) | CH675718A5 (en) |
| DE (1) | DE3843092C2 (en) |
| FR (1) | FR2625193B1 (en) |
| GB (1) | GB2212497B (en) |
| IT (1) | IT1224608B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2384735A (en) * | 1935-08-07 | 1936-03-26 | Imperial Chemical Industries Of Australia & New Zealand Limited | Improvements in or relating tothe production of liquid nitric esters |
| FR2265675A1 (en) * | 1974-03-29 | 1975-10-24 | Lilly Co Eli | Purifying spent nitration sulphuric acid - contg. nitrogen oxides, inorganic and organic fluorides, and organic cpds |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1546910A (en) * | 1922-05-29 | 1925-07-21 | Du Pont | Process of concentrating nitric acid |
| GB298894A (en) * | 1927-10-15 | 1929-05-23 | Arnold Schmid | Process of and apparatus for denitrating residuary acids |
| US3555693A (en) * | 1968-09-27 | 1971-01-19 | Bangor Punta Operations Inc | Method and apparatus for treating pieces of material by microwaves |
| IN141261B (en) * | 1973-06-29 | 1977-02-05 | Meissner J |
-
1987
- 1987-12-23 FR FR8718033A patent/FR2625193B1/en not_active Expired - Lifetime
-
1988
- 1988-12-13 CH CH4604/88A patent/CH675718A5/fr not_active IP Right Cessation
- 1988-12-21 DE DE3843092A patent/DE3843092C2/en not_active Expired - Lifetime
- 1988-12-22 IT IT8868140A patent/IT1224608B/en active
- 1988-12-22 GB GB8829980A patent/GB2212497B/en not_active Expired
- 1988-12-23 AU AU27403/88A patent/AU623871B2/en not_active Ceased
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2384735A (en) * | 1935-08-07 | 1936-03-26 | Imperial Chemical Industries Of Australia & New Zealand Limited | Improvements in or relating tothe production of liquid nitric esters |
| FR2265675A1 (en) * | 1974-03-29 | 1975-10-24 | Lilly Co Eli | Purifying spent nitration sulphuric acid - contg. nitrogen oxides, inorganic and organic fluorides, and organic cpds |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2625193A1 (en) | 1989-06-30 |
| DE3843092C2 (en) | 1997-02-20 |
| FR2625193B1 (en) | 1991-10-11 |
| DE3843092A1 (en) | 1989-07-13 |
| CH675718A5 (en) | 1990-10-31 |
| GB2212497A (en) | 1989-07-26 |
| GB2212497B (en) | 1991-07-10 |
| IT1224608B (en) | 1990-10-04 |
| AU2740388A (en) | 1989-06-29 |
| IT8868140A0 (en) | 1988-12-22 |
| GB8829980D0 (en) | 1989-02-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| HB | Alteration of name in register |
Owner name: SNPE Free format text: FORMER NAME WAS: SOCIETE NATIONALE DES POUDRES ET EXPLOSIFS |
|
| PC | Assignment registered |
Owner name: SNPE MATERIAUX ENERGETIQUES Free format text: FORMER OWNER WAS: SNPE |