JPH0410516B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for processing carbonaceous materials with hydrogen to produce hydrocarbon liquids and gases suitable for chemical feedstocks and fuels. More specifically, by reacting a solid powdery carbonaceous material such as coal with heated hydrogen and then further reacting it in the coexistence of water vapor, hydrocarbon liquids and gases can be produced in high yields as chemical raw materials and fuels. The present invention relates to a method for treating carbonaceous raw materials produced by.

Various methods are generally known for producing hydrocarbon liquids and gases suitable as chemical feedstocks and fuels from carbonaceous materials such as coal. One such method, US Pat. No. 3,030,297, describes a process that involves heating dry coal particles in a stream of hydrogen to a temperature in the range of 600-1000° C. at a total pressure of about 500-6000 psig. In this method, hydrogen and coal particles are mixed and the mixture is heated from the outside to substantially 450 to 600°C, but this requires a relatively long reaction time of several seconds to one minute.
Some of the decomposition products are further accompanied by hydrogenolysis, which has the disadvantage that, in particular, the production of methane increases significantly, thereby increasing the hydrogen consumption rate.

In addition, Wilburn C. Schroeder, the applicant of the above-mentioned patent, in Japanese Unexamined Patent Application Publication No. 75202/1987, made water vapor coexist in a stream of hydrogen and carbon monoxide, introduced coal particles into the gas, and
It states that by heating the coal to a pressure of 5,000 psi and above 750 psi, hydrogen generation through a reforming reaction is simultaneously performed at the same time as the hydrogen cracking of coal. However, this method has the disadvantage that the hydrogen partial pressure, which is important in the initial decomposition of coal, is reduced by the addition of steam, and the carbonization reaction by condensation polymerization that proceeds simultaneously with thermal decomposition is not suppressed, resulting in a decrease in the yield of useful liquefied products. be.

On the other hand, in JP-A-54-132605, 1000
Granular coal was introduced into a hydrogen stream heated to ~1650°C, and at a reaction temperature of substantially 800-1050°C,
A short reaction process of 0.02 to 1 second is described. Since this method is a short-time coal hydrocracking method that involves rapid heating to high temperatures, the products are mainly relatively heavy hydrocarbon liquids, which are chemical feedstocks or high value-added products. Further secondary treatment processes are required to obtain light fuels.

The present inventors have made extensive studies in order to overcome the above-mentioned drawbacks when hydrocracking carbonaceous materials such as coal to produce hydrocarbon liquids and gases suitable for useful chemical raw materials and fuels. As a result of the addition, (a) a powdered carbonaceous material such as finely divided coal is added and dispersed into a hydrogen stream that has been heated to a predetermined temperature (b) at a temperature range of 500 to 1000°C for 0.01 to 10 seconds. After hydrogenolyzing the powdery carbonaceous material, (c) water vapor is introduced into the reaction gas at a volume ratio of 10 to 70%, and the reaction is continued for an additional 2 to 60 seconds at a temperature range of 500 to 1000°C. By continuing to do so, we have discovered an economical method for producing high yields of hydrocarbon liquids and gases suitable for useful chemical feedstocks and fuels, while at the same time reducing hydrogen consumption rates.

That is, according to the present invention, there is provided a first reaction zone in which pre-pressurized hydrogen is heated, pulverized coal particles are introduced and dispersed into the air stream, and the coal particles are rapidly thermally decomposed; Water vapor is introduced into the gas mixture so that the volume ratio becomes 10 to 70%, preferably 20 to 50%, and further 2 to 50% is added to the mixed gas.
Providing a second reaction zone to carry out the hydrogenolysis reaction for 60 seconds, preferably 5 to 20 seconds, increases the yield of useful chemical raw materials, especially benzene, toluene, xylene and ethane, while at the same time reducing the yield of methane. and hydrogenation (formula) of carbon dioxide produced by coal decomposition and methanation (formula) of carbon monoxide CO ₂ + H ₂ → CO + H ₂ O CO + 3H ₂ → CH ₂ + H ₂ O Furthermore, by performing hydrogen generation according to the following formula: C+H ₂ O→CO+H ₂ CO+H ₂ O→CO ₂ +H ₂ , the apparent hydrogen consumption rate can be reduced and economical efficiency can be improved.

In the thermal decomposition of solid carbonaceous materials such as coal, it is necessary to maintain a high hydrogen partial pressure in order to increase the decomposition yield, and the present invention decomposes the primary products to produce useful products. They found that it is effective to coexist with water vapor in order to obtain it economically, and have made it possible to carry out this simultaneously in the same reaction system.

In the present invention, a hydrocracking zone by rapid heating of coal and a secondary cracking zone by introducing steam are successively provided, and in order to limit the reaction time in each zone, the reactor type is a parallel flow type. For example, preheated hydrogen and coal particles are supplied from one end of the reaction tube, and when a set residence time has elapsed, superheated steam is introduced at a predetermined rate from the side tube. However, it can be designed so that it reaches the outlet of the reaction tube after a predetermined reaction time has elapsed. Notwithstanding the foregoing, it goes without saying that all reactors that can satisfy the method and conditions of the present invention are included in the present invention.

According to the present invention, in order to heat the coal to a predetermined temperature and start the reaction, part or all of the introduced hydrogen is preheated in advance. The method may be conventional heater heating, partial combustion of introduced hydrogen, or a combination thereof. The reaction temperature of heated hydrogen and coal particles is 500-1000℃, preferably 600-900℃
It is ℃. At high temperatures, the decomposition of coal into methane progresses, and at low temperatures, the coal reaction does not proceed. The ratio of hydrogen to coal introduced is preferably in the range of 0.1:1 to 1:1 by weight. The hydrogen preheating temperature is determined in consideration of the coal feed amount, reaction temperature, etc.

The hydrogen used in this process may be from any industrial source, for example from the gasification of char and/or coal, the reforming of naphtha and/or methane, and may be partially contaminated with methane, carbon monoxide, etc. do not have. The carbonaceous materials used include, for example, coal, lignite, lignite, peat, oil shale, tar sand, tar pitch, and the like.

When these are supplied in solid form, they are dried in advance and ground to 500 microns or less, preferably 100 microns or less (150 meshes or less) before use.

It is also possible to use a catalyst effective for hydrogenolysis of these carbonaceous materials.

According to the present invention, after the decomposition reaction of coal particles is carried out in the aforementioned reaction gas consisting essentially of hydrogen, water vapor is introduced into the mixed gas, and the reaction is further continued. The reaction temperature is 500~1000℃ especially 600~
A range of 900°C is preferable, and steam may be superheated to maintain that temperature. Further, part or all of the water vapor to be added can also be introduced as water. Reaction pressure is 10-200Kg/cm ² ,
Preferably 30-100Kg/ ^cm2 , reaction time is 0.01-10Kg/cm2 in the first reaction zone under hydrogen atmosphere.
seconds, preferably 0.1 to 2 seconds, in the second reaction zone with added steam 2 to 60 seconds, preferably 5 to 20 seconds.
seconds, and these depend on the type of carbonaceous material used as the raw material;
Determined by the type of product required. For example, the optimum value can be selected depending on whether the target is a gaseous product such as ethane or a light liquid product such as benzene, toluene, or xylene.

The products of the reaction include gaseous and liquid conversion products of coal, as well as unreacted coal, coal, and hydrogen. The reaction product from the second reaction zone is heated below 600°C, preferably at 400°C to stop the reaction.
It is cooled below ℃. This method can use existing indirect heat exchangers, water sprays and coolants such as gases such as cryogenic hydrogen or various hydrocarbon liquids.

Examples and comparative examples are shown below to explain the features of the present invention. Note that this example shows one embodiment of the present invention, and the present invention is not limited thereto.

Example 1 Lignite having the composition shown below was ground to 100 mesh or less, dried, and used.

Composition (dry basis) C: 59.8% H: 4.5% N: 0.4% S: 3.5% O: 20.2% Ash content: 11.6% Compressed hydrogen heated to 800°C supplied per 1 kg of coal
It was continuously supplied at a rate of 0.5 kg from the top of a reaction tube with an electric heater, having an inner diameter of 22 mm and a reaction tube length of 3 meters. (See Figure 1) Reaction temperature 800℃, reaction pressure
After a reaction time of 1 second under the condition of 70Kg/ ^cm2 , superheated steam was added from the side tube of the reaction tube so that the steam partial pressure in the reaction gas was 20%, and the reaction was continued for another 6 seconds at the same temperature. continued. Product at 400℃
After rapid cooling to and separation of the solid char, the gaseous and liquid products were collected and analyzed with the following results.

Reaction yield (anhydrous and ashless basis) Methane 12% Ethane 10% CO 3% CO ₂ 12% Benzene 12% Toluene 1% Light oil (BP < 400℃) 15% Hydrogen consumption 2.8% (for 100% anhydrous and ashless coal) Comparative Example 1 The same lime as in the example was used, the same reactor was used, and no steam was introduced. The reaction conditions were 800° C., 70 Kg/cm ² and a reaction time of 7 seconds, and the other conditions were the same as in the examples.

The results are shown below.

Reaction yield (anhydrous and ashless basis) Methane 28% Ethane 5% CO 12% CO ₂ 0.5% Benzene 7% Toluene 0.1% Light oil (BP＜400℃) 8% Hydrogen consumption rate 5.6%

[Brief explanation of drawings]

FIG. 1 is a block flow diagram illustrating an example of an apparatus for carrying out the method of the present invention. 1...Coal feeder, 2...Hydrogen preheater, 3...Reactor, 4...Char separator, 5...Cooler, 6...Liquid product recovery device.

Claims (1)

[Scope of Claims] 1. A treatment method for producing a hydrocarbon liquid and gas by hydrogenating a powdery carbonaceous material, which includes (a) introducing a finely divided powdery carbonaceous material into a preheated hydrogen gas stream; After adding and dispersing (b) hydrogenolyzing the powdered carbonaceous material for 0.01 to 10 seconds at a temperature range of 500 to 1000°C, (c) adding water vapor to the reaction gas at a volume ratio of 10 to 70%. Method 2 for treating carbonaceous materials, characterized by introducing the powder into a carbonaceous substance and continuing the reaction for an additional 2 to 60 seconds at a temperature range of 500 to 1000°C.Characterized by the fact that the powdered carbonaceous substances are coal of about 500 microns or less. A method for treating a carbonaceous material according to claim 1. 3. The method for treating a carbonaceous material according to claim 1, wherein the reaction pressure is 10 to 200 Kg/cm ² .