FR2493308A1 - INTEGRATED INSTALLATION FOR THE SYNTHESIS OF METHANOL FROM GAZEIFIED HOLES - Google Patents

Abstract

INTEGRATED PLANT FOR THE SYNTHESIS OF METHANOL FROM CARBONATED COAL. THIS INSTALLATION, WHICH ALSO PRESENTS AN APPARATUS 1 FOR HYDROGENING COAL GASIFICATION AS A METHANE DISSOCIATION OVEN 6 POSSIBLY HEATED BY A NUCLEAR REACTOR 25 AT HIGH TEMPERATURE, IS CHARACTERIZED BY THE FACT THAT THE TWO GAS CURRENTS CARBONIC AND MIXED SENT TO A METHANOL SYNTHESIS STATION 11. THE METHANOL OBTAINED IS SEPARATED FROM THE GAS IN A SEPARATOR 13 AND THIS GAS IS SCINTED INTO ITS CONSTITUENTS IN A LOW TEMPERATURE SEPARATION DEVICE 14. THE HYDROGEN RETURNS TO THE HYDROGENING CARBONATION UNIT 1 AND THE METHANE TO THE DISSOCIATION OVEN 6, WHILE THE NITROGEN IS SEPARATED AND THE CARBON OXIDE RETURNS TO THE METHANOL SYNTHESIS STATION 11. THANKS TO THIS INTEGRATION, THE QUANTITY OF THE HYDROGEN CURRENT RECYCLED IN THE INSTALLATION IS SIGNIFICANTLY REDUCED, WHICH RESULTS IN SAVINGS IN PIPING, PUMPS, ETC. THE HOT FLUID COMING OUT OF THE DISSOCIATION OVEN 6 CAN HEAT A STEAM BOILER 19 IN A LOWER TEMPERATURE ZONE, STEAM WITH WHICH A TURBO-GENERATOR 20, 21. THE STEAM SUPPLIED FROM THE IMPELLER IS SENT TO THE DISSOCIATION OVEN.

Description

"Integrated plant for the synthesis of methanol from

carbonated coal. "

  The present invention relates to an integrated plant for the synthesis of methanol from carbonated coal,

  especially using nuclear energy.

  Methanol is gaining a lot of importance both directly as a motor fuel, and as a fuel.

  intermediate product for the manufacture of gasoline

  shot of coal. Gasification processes for coal

  creating what is called a "synthesis gas" offer a pos-

  sibility of preparing methanol. Such a synthesis gas

  consists largely of hydrogen and oxy-

  of carbon and also contains small amounts of carbon dioxide. The synthesis gas can be prepared by reacting the methane, obtained in a hydrogenation gasification apparatus of the coal, with the steam in an oven

  dissociation of methane by heating at very high temperatures

ture.

  In the German patent application to the public inspection

  that NO 28 37 988.6 is described an installation for the manufacture

  cation of the synthesis gas from coal, in particular

  to bind using nuclear energy.

  In the German magazine "Kerntechnik" (1975) NI 4, pages 181 to 187 deal with the gasification of coal using heat from high temperature nuclear reactors etc. In the book "Chemierohstoffe aus Kohle" by JUrgen Falbe, 1977, Editions Georg-Thieme, Stuttgart,

  pages 300 to 322 mention is made of the current methods of preparing

  methanol from the synthesis gas. According to the

  157 on page 306, we can see that a large part of

  the hydrogen leaving the methanol separator must be

  recycled to the methanol synthesis station at

  means of a device for recycling gases and a compres-

  recycling. Also, in hydrogenation gasification

  coal already referred to above requires an ex-

  hydrogen so that a strong current of hydro-

  gene is practically recycled. Both recycling of the

  need considerable expenditure of pipelines

and compressors.

  The object of the present invention is an installation

  for the preparation of methanol from coal gas

  in which the expenditure mentioned above for

  the recycling of hydrogen is considerably reduced.

  To achieve this object the author of the present invention

  proposes an installation comprising a gasification apparatus

  hydrogenation of coal, a dissociation furnace

  methane, as well as heat exchangers and compressors.

  It is characterized in that (a) the methanol synthesis station is fed with a stream of synthesis gas leaving the methane dissociation furnace, and

  with a gas stream containing methane coming out of the

  hydrogenation gasification of the boiling, (b) the

  The mixture of the various gases leaving the methanol synthesis station is, after condensation and separation of the methanol, separated in a low-temperature gas separation device; (c) the methane stream leaving the separation device

  Low temperature gas is sent to the dissociation furnace.

  methane (d) the hydrogen stream coming out of the

  low-temperature gas separation system is sent to the hydrogenation gasification apparatus of the coal,

  (e) the carbon monoxide stream exiting the separation device

  paration of the gases at low temperature, is sent to the methanol synthesis station. Thanks to this integration of the methanol synthesis station in the coal gasification plant, the total recycled hydrogen stream is particularly small so that the associated pipelines and compressors can be mounted with an expense. significantly lower. The coal used is gasified and hydrogenated with hydrogen and the raw gas

  outgoing, after cooling and / separation of the carbon dioxide

  and hydrogen sulfide, is mixed with the synthesis gas leaving the methane dissociation furnace. This mixture is sent to the methanol synthesis station and is converted to methanol up to more than 90% in a single pass. The gaseous mixture remaining, after condensation and separation of the methanol, with a large part of the hydrogen, part of the methane and a small portion of unreacted carbon monoxide, is split in these three fractions into the

  device for separating gases at low temperature. The neck-

  methane is sent to the dissociation furnace with the water vapor, the hydrogen stream is sent to the hydrogenation gasification device of the coal and the

  carbon monoxide stream is sent to the synthesis station.

  se methanol. The heat needed to dissociate the

  methane can be obtained either from a nuclear reactor or

  re is from the residual coke leaving the hydrogenating gasification device. With the proposed installation, at the entrance to the methanol synthesis station, we obtain a

  very high ratio of hydrogen to carbon monoxide,

  a very large amount of methanol is formed after a single pass. While in the above-mentioned book of Falbe, page 305 is given an H2 / CO ratio of about 3.5, the present plant can be run at a ratio of 5 or higher. Also, the low-temperature gas separation device required for a hydrogenation gasification plant of the coal is particularly small because of the proposed integration of the methanol synthesis station. In the summary position of the

  conventional methanol there is no provision for separating

  gas at low temperature, so that the nitrogen that accumulates in the circuit must be removed after separation of methanol. This leads to an inevitable loss of hydrogen and carbon monoxide which, because of the amount of nitrogen, can no longer be used in the installation but only

burned.

  The single figure shows a schematic assembly of a realization of the installation. In addition, the various parts of the installation are designated as usual by

  figures, while the letters refer to Table 1 below.

  joint in which are indicated the compositions and the state of the gases towards the various points. Table 2 contains the data concerning the coal that is the basis of the calculations and the data relating to the residual coke formed from this coal. Table 3 contains the essential data of the installation. In the hydrogenation gasification apparatus 1 of the coal, the coal according to Table 2 is gasified, and the residual coke is removed. The gas that comes out heats the gas that enters, is then cooled in 3, freed of dust with water in 4 and freed of carbon dioxide

  and hydrogen sulfide at 5. In dissociation furnace 6

  a mixture of methane, water vapor and carbon dioxide.

  is dissociated in synthesis gas, cooled in 7 and 8,

  rid of carbon dioxide in 9 and compressed with

  10. The gas streams leaving at 5 and 10 are

  mixed and sent to the station 11 of methanol synthesis.

  The gaseous mixture and the methanol leaving there are cooled to 12 and separated into 13. The gaseous mixture largely free of methanol is split in a device 14 for separating the gases at low temperature. The carbon monoxide is compressed with the compressor 15 and sent to the methanol synthesis station 11. The hydrogen is compressed with the compressor 16 and sent to the hydrogenation gasification apparatus 1 of the coal passing through the heat exchanger 2, while the methane is compressed with the compressor 17 and is sent to the furnace 6 of dissociation. The nitrogen that is formed in addition to 14 is no longer used in the installation. The gas

  carbon dioxide that forms in 9 may be at least partly

  awarded with the compressor 18 and sent to the dissociation furnace 6. The dissociation furnace 6 can be heated by

  the helium cooling circuit of a nuclear reactor

  25 key at high temperature. In the case where helium

  both of the dissociation furnace 6 are used for the production of steam at 19, from where this steam is first expanded in a steam turbine 20 and is used to make current and is then partly relaxed in the same

  turbine and sent partly to the dissociation furnace 6.

  The steam circuit further comprises a refrigerant 22 and

  a feed pump 23, while the circuit of the

  lium still has a cannon 24.

TABLE 1

  Composition and state of aaz Composition of gases in H2 Location

CO CO2 CH4 C2H6 H2S

mN3 / s Pressure

N2 H20

A 173.3

B 173.3

C 261.5

D 261.5

E -

F 278.3

G -

H, 173.3

I 434.7

K 278.3

L -

M -

NOT -

O -

P -

  Q 8.2 8.2 67.8 67.8, 7 13.9 81.7, 7 0.7 96, 9 96, 9 82.2 14, 6 0.7, 7, 7 58.1 58, 1,133.8, 7,133.8 133.8 2,3 2,3 2, 3 2,3 2,3 2,3 0,8 w 1,1 1, 1 1, 1 1, 1 1,1 1 , 1 Ili 1, 1, He

- - 0.8

- - 82.2 133.8 2.3

  , 2 0.9 371.8 1.3 0.9 2.1 0, 1 3.3 2.8 0, 5

- 0,1

272, 2

261.5

856, 0

388, 6

7

278, 3

136, 1

267.2 655.8

421, 3

  1.1, 2, 0, 1 1.5 1.5 73.5 1.7 1.5 1.7 1.7 1.7

- 468.0 686.3 45

  Total bar Temp. oC in Mx a-% O w c, Co aU

TABLE 2

Flaming gas charcoal

C H

, 3 4.6 o 6.5 N 1.5

S H20

1.1

6.7 4.3%

Coke waste

0.97 0.51

0.76 0.41

- 10.96%

TABLE 3

  Main data of the installation Nuclear reactor Thermal power Output temperature of helium (core) Release temperature of helium (dissociation furnace) Temperature of helium input (nucleus) Production of raw current Requirement in current of the whole installation Sale of current outside

3000 MW

900C 7000C 2500C

602.8 MW

530.8 MW

  72 MW Coal gasification Amount of coal (H * = 29977 KJ / kg) 415.7 t / ho Coke waste production (He = 26052 KJ / kg) 163.1 t / h Synthesis gas (H2 / CO = 2 , 06) 837. 10 mn / h (reacted in methaol synthesis) (reacted in methahol synthesis) Methanol production Gross calorific value 391.0 t / h Ash 86.39

Claims (1)

CLAIM   Installation for the preparation of methanol   carbonated coal with a gasification device   hydrogenation of coal, a methane dissociation furnace, a methanol synthesis station and   heat exchangers and conventional compressors, characteris-   in that: a) the methanol synthesis station (11) is fed with a stream of synthesis gas leaving the methane dissociation furnace (6) and with a gas stream containing   methane coming out of the hydro-gasification apparatus (1)   the genitals of coal; b) the mixture of the various gases leaving the station (11) of   Methanol synthesis is separated after condensation and separation.   methanol in a low temperature gas separation device (14); c) the methane stream leaving the low temperature gas separation device (14) is sent to the methane dissociation furnace (6); d) the hydrogen flow leaving the device (14) of   separation of low temperature gases is sent to the   the same (1) hydrogenation gasification of coal; e) the carbon oxide stream exiting the low temperature gas separation device (14) is sent   to the methanol station (11).