Source: https://patents.google.com/patent/US4663931A/en
Timestamp: 2018-03-23 23:02:36
Document Index: 432473156

Matched Legal Cases: ['art 2', 'art 3', 'art 30', 'art 31', 'art 31', 'art 3', 'art 43', 'art 42']

US4663931A - Power generating station with an integrated coal gasification plant - Google Patents
Power generating station with an integrated coal gasification plant Download PDF
US4663931A
US4663931A US06855751 US85575186A US4663931A US 4663931 A US4663931 A US 4663931A US 06855751 US06855751 US 06855751 US 85575186 A US85575186 A US 85575186A US 4663931 A US4663931 A US 4663931A
US06855751
Power generating plant with an integrated coal gasification plant, with a heat exchanger and gas purification plant connected to the coal gasifier, with a gas turbine and steam power generating plant part connected to the heat exchanger and gas purification plant, and with a methanol synthesis plant. The methanol generated in the methanol synthesis plant as well as the synthesis exhaust gas of the methanol synthesis can be fed, at least partially, to a further subplant for a second chemical manufacturing process and the excess synthesis exhaust gas from the methanol synthesis and the exhaust from this further subplant, to the combustion chamber of the gas turbine power generating plant part.
This is a division of application Ser. No. 614,325, filed May 25, 1984 (allowed).
British Patent 20 75 124 discloses a power generating plant in which a gas turbine is supplied with synthesis gas from a coal gasification plant. The gas turbine drives an electric generator. The waste heat of the gas turbine is utilized in this power generating plant for generating steam. A steam turbine and a further electric generator are driven with the steam. Part of the synthesis gas produced is fed to a methanol sythesis plant. The methanol produced is stored in this power generating plant and is burned in the gas turbine in addition to the synthesis gas for equalizing load peaks. This power generating plant at times of low load, generates methanol to an increased extent and the so-produced methanol can be sold as raw material unless it is needed for equalizing peak loads. Apart from the fact that only a small part of the produced methanol is available as a product of the plant due to frequent levelling out of peak loads, the production costs for the methanol are not substantially lower than those of corresponding production processes which are independent of a power generating station.
An object of the invention is to improve the efficiency of such a power generating station and to produce in the process chemical raw materials inexpensively.
In a power station of the type mentioned at the outset, the methanol of the methanol synthesis plant as well as the synthesus waste gas of the methanol synthesis are fed, according to the invention, at least partially to a further subplant for treatment in a second chemical production process. The excess synthesis waste gas from the methanol synthesis and the exhaust gas from this second partial plant are directed to the combustion chamber of the gas turbine power generating part. These two mutually coupled subplants, each for a chemical production process, are integrated into the power generating plant through the use of the synthesis gas produced for the production of methanol and by feeding a part of the methanol and the exhaust gas from the methanol synthesis to another chemical production process. This integration enables these chemical raw materials to be produced at least cost. Due to the combustion of the excess synthesis waste gases in the combustion chamber of the gas turbine, the expense for establishing stoichiometric conditions of the starting gases can be reduced, without thereby losing the energy content of the incompletely reacted synthesis waste gases.
An even closer approximation of the desired stoichiometric ratio of H2 to CO in the composition of th synthesis gas to the methanol synthesis reactor can be achieved by associating the methanol the methanol reactor with a water electrolyzing plant which converts water into oxygen and hydrogen. Oxygen from the water electrolizing plant is connected to the coal gasifier and a hydrogen line is connected to the gas line leading to the methanol synthesis reactor. Thereby, the material yield of methanol can be improved considerably and at the same time, the air separation plant preceding the coal gasifier is relieved of part of its load of separating air into oxygen and nitrogen.
The gas turbine 23 of the gas turbine power generating plant part 2 drives an air compressor 24 for the combustion air as well as a generator 25. The waste heat boiler 27 is connected to the exhaust gas line 26 of the gas turbine. The steam turbine 29 of the steam power generating station part 3 is connected to the steam line 28 of the waste heat boiler 28. In the embodiment example, the steam turbine 29 consists of a high-pressure part 30 and a low pressure part 31. The steam turbine 29 is coupled to a generator 32. The low pressure part 31 of the steam turbine 29 is followed by a condensor 33, a condensate pump 34, a feedwater tank 35 and various feedwater pumps 36, 37.
Milled coal, oxygen from the preceding air separation plant 6 as well as process steam are fed to the coal gasifier 5. The hot raw gas generated in the coal gasifier 5 first gives off its heat in the heat exchanger plant 7. The raw gas from the gasifier is a mixture of constituents including CO2, CO, H2, H2 S and dust. The heat generates steam which is fed as live steam to the steam power generating plant part 3. Dust particles are separated from the raw gas in the dust separator 8 connected to the heat exchanger plant 7. Carbon dioxide and hydrogen sulfide are thereafter separated from the raw gas in the gas purifier 9. The purified gas containing CO and H2 leaving the gas purifier 9 is fed via the purified gas line 18 to the methanol synthesis plant 10 as well as to the gas separation plant 17. In the methanol synthesis reactor 11, the purified gas is in part converted into methanol by reaction of 2H2 +CO CH3 OH. The reaction is incomplete for the reason that the ratio of H2 to CO in the purified gas is in the range of 0.5 to 1 instead of at the stoichiometric ratio of 2. In order to bring the composition of the purified gas fed to the methanol synthesis reactor closer to the stoichiometric ratio desired for the methanol synthesis reaction, a gas separation plant 17 is connected to the purified gas line 18 leaving the gas purifier 9 to separate hydrogen or a fraction rich in hydrogen from the purified gas. The hydrogen separated in the gas separation plant 17 is admixed via a return line 38 to the purified gas 18, which flows into the methanol synthesis reactor 11. This increases the hydrogen content of the purified gas entering the methanol synthesis reactor. This, in turn, has the result that a larger percentage of the purified gas/hydrogen mixture directed to the methanol synthesis plant 10 can be converted into methanol. The exact composition of the gas mixture fed to the methanol synthesis reactor can be controlled via the control valve in the purified gas line 18 leading to the methanol synthesis reactor 11 and the control valve in the line leading from line 18 to gas separaton plant 17. At times of low load, if little electric energy is taken off the power generating station 1, additional hydrogen and oxygen can be produced by connecting-up water electrolysis cells 39. The oxygen can be fed to the coal gasifier 5, as shown by the line leading from water electrolysis cells 39 to coal gasifier 5. The hydrogen from electrolysis can be admixed to the purified gas in line 18 prior to entrance into reactor 11 to obtain an approximation of the stoichiometric ratio desired for the methanol synthesis.
The hot exhaust gases of the gas turbine 23 are conducted via the exhaust gas line 26 into the exhaust heat boiler 27. There, waste heat in the hot exhaust gases is used for generating steam. The steam generated in the waste heat boiler 27 as well as additional steam generated in the heat exchanger plant 7 are fed to the steam turbine 29. The process steam which is required as gasification steam and as heating steam for individual steps of the production process, is taken from the steam turbine at the appropriate pressure stages.
In FIG. 2, as is FIG. 1, raw gas is generated in the coal gasifier 45 through reaction of milled coal with oxygen and process steam. The heat of the latter is utilized in the heat exchanger plant 47 for generating steam which can be used, as desired, as process steam or as feed steam for the steam generating plant part 43. In the gas dust separator 48, the raw gas is freed to dust particles and, at the same time, enriched with steam. In the gas purification plant 49, hydrogen sulfide gas and carbon dioxide are removed. The remaining purified gas which contains substantially hydrogen and carbon monoxide, is fed here with unchanged composition to the continuous flow methanol synthesising plant 52. Because the ratio H2 to CO is in the range of 0.5 to 1, i.e. is still far removed from the stoichiometric ratio of 2, the conversion to methanol is substantially smaller than it would be if the purified gas had the desired stoichiometric composition. In the following methanol separator 51, the methanol is separated from the exhaust gas of the methanol synthesis. The exhaust line 54 and the methanol output line 55 of the methanol separator 51 are connected to the plant 53 for producing vinyl acetate.
It is of benefit if in a plant for generating vinyl acetate connected to a methanol synthesis plant 52 fed with purified gas from a coal gasifier, the overall stoichiometric ratio of H2 to CO for the production of vinyl acetate via methanol from a starting gas containing H2 and CO is 0.5. Such a starting gas is similar to the composition of the purified gas. This makes unnecessry a gas separation plant for enriching the purified gas with hydrogen as in the acetic acid synthesis. The excess methanol is available as a salable chemical raw material. The residual gases and liquid residues of the plant 53 for the manufacture of vinyl acetate as well as the unused portions of the synthesis exhaust gas from the methanol separator 51 can be fed to the gas turbine power generating plant part 42 and can be burned there. Their chemically bound energy is therefore not lost. Because of the possibility of burning the synthesis exhaust gas, the cost for the gas purification can be reduced as compared to known manufacturing processes because there, also the raw gas stream branched off for the vinyl acetate production must be purified to completely remove carbon dioxide and hydrogen sulfide. The vinyl acetate can therefore also be produced more inexpensively and can be sold, like the methanol, as a chemical raw material.
1. Power generating station with an integrated coal gasification plant comprising
(c) a steam generating station which includes a steam generator connected to an exhaust gas line of the gas turbine, a high pressure and low pressure steam turbine, a feedwater tank to collect the condensate and a feedwater pump to feed water to the steam generator,
(e) a methanol synthesis plant having a methanol synthesis reactor for the partial conversion of the purified gas from the gasifier into methanol and a methanol separator connected to the synthesis reactor for the separation of the reaction products from the synthesis reactor into liquid methanol and methanol synthesis exhaust gas,
(f) an additional vinyl acetate synthesis plant for the utilization of at least part of the methanol and the methanol synthesis exhaust gas to produce vinyl acetate and a residual gas as a byproduct, and connecting means for supplying excess methanol synthesis exhaust gas and residual gas to the combustion chamber, including a water electrolysis plant wherein water is dissociated into oxygen and hydrogen, an oxygen line connected from the electrolysis plant to the coal gasifier and a hydrogen line to a gas feedline leading to the methanol synthesis reactor.
2. Power generating station with an integrated coal gasification plant comprising
(b) a gas turbine power plant which includes gas turbine, a combustion chamber of the gas turbine, an air compressor for introduction of air into the combustion chamber, and a generator coupled to the turbine,
(f) an additional vinyl acetate synthesis plant containing a vinyl acetate reactor for the utilization of at least part of the methanol and the methanol synthesis exhaust gas to produce vinyl acetate and a residual gas as a byproduct, and connecting means for supplying excess methanol synthesis exhaust gas and residual gas to the combustion chamber, and
(g) a gas separation plant is connected to a gas feedline to the methanol synthesis reactor said gas separation plant adapted to separate a fraction rich in hydrogen and a fraction rich in carbon monoxide from gas from the feedline, connecting means for admixing the hydrogen-enriched fraction to the gas stream flowing through the feedline into the methanol synthesis reactor, and connecting means for feeding the carbon monoxide-enriched fraction to the vinyl acetate reactor as well as to the combustion chamber of the gas turbine power generating plant.
3. Power generating station according to claim 1, wherein the methanol synthesis plant is without a recirculation line and loop compressor for recirculating methanol synthesis exhaust gas.
4. Power generating station according to claim 1, including connecting means to feed the exhaust gases from the plant for producing vinyl acetate together with the excess synthesis exhaust gas of the methanol synthesis plant to the combustion chamber of the gas turbine power generating plant.
5. Power generating station according to claim 1, wherein the methanol synthesis plant and the additional synthesis plant are adapted to utilize, at least partially, heat liberated in the methanol synthesis plant and in the additional synthesis plant for the generation of steam.
6. Power generating station according to claim 2, wherein the methanol synthesis plant is without a recirculation line and loop compressor for recirculating methanol synthesis exhaust gas.
7. Power generating station according to claim 2, including connecting means to feed the exhaust gases from the plant for producing vinyl acetate together with the excess synthesis exhaust gas of the methanol synthesis plant to the combustion chamber of the gas turbine power generating plant.
8. Power generating station according to claim 2, wherein the methanol synthesis plant and the additional synthesis plant are adapted to utilize, at least partially, heat liberated in the methanol synthesis plant and in the additional synthesis plant for the generation of steam.
9. Power generating station according to claim 4, including connecting means for distributing steam generated in the heat exchanger and gas purification plant together with the steam generated in the steam generator to the steam turbine of the steam power generating station part and as process steam for the chemical production of methanol and vinyl acetate.
US06855751 1983-06-03 1986-04-24 Power generating station with an integrated coal gasification plant Expired - Fee Related US4663931A (en)
DE19833320227 DE3320227A1 (en) 1983-06-03 1983-06-03 Power plant with an integrated coal gasification plant
DE3320227 1983-07-03
US06614325 Division US4665688A (en) 1983-06-03 1984-05-25 Power generating station with an integrated coal gasification plant
US4663931A true US4663931A (en) 1987-05-12
ID=6200650
US06614325 Expired - Fee Related US4665688A (en) 1983-06-03 1984-05-25 Power generating station with an integrated coal gasification plant
US06855751 Expired - Fee Related US4663931A (en) 1983-06-03 1986-04-24 Power generating station with an integrated coal gasification plant
US (2) US4665688A (en)
EP (1) EP0128404B1 (en)
JP (1) JPH0472044B2 (en)
CA (1) CA1233324A (en)
DE (1) DE3320227A1 (en)
DK (1) DK156967C (en)
ES (1) ES8503072A1 (en)
FI (1) FI75651C (en)
WO2007019643A1 (en) * 2005-08-19 2007-02-22 Varipower Technology Pty Ltd Method for generating power
DE19514403A1 (en) * 1995-04-19 1996-10-24 Linde Ag Prodn. of methanol as power source in power station
DE102006034712A1 (en) * 2006-07-27 2008-01-31 Izes Ggbmh Method of reducing the CO2 emissions of fossil-fueled power plants
EP2426236B1 (en) * 2010-09-03 2013-01-02 Carbon-Clean Technologies AG Method and fuel generation assembly for the carbon dioxide-neutral compensation of energy peaks and troughs in the generation of electrical energy and/or for producing a fuel containing hydrocarbons
DE102016003927A1 (en) 2016-03-31 2017-10-05 Christian Blank Combined power plant of a coal gasifier, a steam power plant and a hydrogen engine for power generation from coal or by upstream hydrothermal carbonization, from any biomass, with optional methanol production
GB1572071A (en) * 1977-06-28 1980-07-23 Texaco Development Corp Production of purified synthesis gas and carbon monoxide
Foster Pegy, R. W., The Integration of Gasification with Combined Cycle Power Plants , in Combustion; Dec. 1979. *
Foster-Pegy, R. W., "The Integration of Gasification with Combined Cycle Power Plants", in Combustion; Dec. 1979.
Hamilton & Lehman, "Novel Gas Turbine Cycles with Coal Gasification", ASME Paper 79-WA/Ener-6; Dec. 1979.
Hamilton & Lehman, Novel Gas Turbine Cycles with Coal Gasification , ASME Paper 79 WA/Ener 6; Dec. 1979. *
DK156967C (en) 1990-03-19 grant
EP0128404B1 (en) 1989-08-09 grant
DK265884D0 (en) 1984-05-30 grant
FI841857A0 (en) 1984-05-09 application
ES8503072A1 (en) 1985-05-01 application
FI75651C (en) 1988-07-11 grant
DE3320227A1 (en) 1984-12-06 application
JPH0472044B2 (en) 1992-11-17 grant
FI75651B (en) 1988-03-31 application
EP0128404A2 (en) 1984-12-19 application
ES533063D0 (en) grant
JPS603432A (en) 1985-01-09 application
DK156967B (en) 1989-10-23 grant
DK265884A (en) 1984-12-04 application
US4665688A (en) 1987-05-19 grant
CA1233324A1 (en) grant
FI841857D0 (en) grant
CA1233324A (en) 1988-03-01 grant
EP0128404A3 (en) 1987-03-25 application
ES533063A0 (en) 1985-02-01 application
FI841857A (en) 1984-12-04 application