JPH0210194B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method and apparatus for treating oil shale. More specifically, there is a moving grid, and there are fixed wind boxes above and below the moving grid, and there is a water seal between the wind box and the moving grid, so that the gas inside the wind box does not leak out. After drying and carbonizing the oil shale in the moving lattice type apparatus, the oil shale is crushed in a crushing section to reduce the particle size. After adjustment, the heat amount held by the oil shale is efficiently recovered within a plurality of sections forming a fluidized bed state. An object of the present invention is to provide a method for recovering oil and heat from oil shale using a device combining a moving grid type device, a crushing device, and a fluidized bed device, which eliminates the drawbacks of the conventional methods. (2) To make the operation of the fluidized bed combustion tower easier by crushing the lumps of oil shale carbonized in the combustion apparatus and adjusting the particle size; (2) to reduce the solid particle size of the oil shale (3) To improve the thermal efficiency of the Oil Sier carbonization plant, 4) It is possible to produce carbonized gas with a high calorific value by using low-grade heat such as waste heat of combustion exhaust gas, and (5) High quality is achieved because gas containing oxygen such as combustion exhaust gas is not used in the carbonization section. (6) The above items (1), (2), (3), (4), and (5) can be produced even in an oil-siel carbonization plant of the minimum necessary size. What can be achieved. In other words, the purpose is to provide an economical oil siel carbonization plant. A method for carbonizing oil shale using a moving grid device has already been proposed in JP-A-57-207682, and a method and device for carbonizing oil-bearing minerals using a fluidized bed has already been proposed in JP-A-57-1781. However, the present invention proposes an improvement in the technique of carbonizing oil shale more efficiently by combining these methods. Thermal decomposition characteristics of oil sierre differ depending on where it is produced. Furthermore, the amount of attached moisture and crystallized water also varies considerably depending on the production area (see No. 1). Also,
Even in the case of the same production area, it varies from 3 to 3 depending on the location of the strata.
The amount of attached moisture changes by 10wt.% (see Table 2). Therefore, when carbonizing oil siere with a low content of attached moisture or crystallized water, it is necessary to
By combining the technology proposed in Publication No. 19385 into a drying section and a carbonization section into one section and causing drying and carbonization to occur within the same section, oil can be efficiently recovered from oil shale. The present invention relates to a technique that improves the invention proposed in JP-A-58-19385 and applies it to a method for recovering oil from oil shale that has a low content of attached water and crystallized water.

【table】

[Table] In the preheating and carbonization section, when the adhering water and crystallized water evaporate, cracks occur in the oil sheer lumps, resulting in lumps with different diameters. When oil siel is carbonized, approximately half of the hydrocarbon compounds initially contained in it are released as carbonized oil and gas, but after carbonization, the active ingredients, mainly carbonaceous, remain in the oil siel after carbonization. Approximately half of the content remains. Therefore, as a method of recovering this effective carbonaceous material, there is a method of recovering it as thermal energy by burning the carbonaceous material with oxygen-containing gas, as proposed in the aforementioned Japanese Patent Application Laid-Open No. 1781-1981. . In this case, in the carbonaceous combustion process in the oil siel solid particles, the reaction gradually progresses from around the solid particles toward the inside. This combustion reaction rate is fast on the surface of the solid particle, but as the reaction progresses inside, the rate at which oxygen diffuses into the solid particle becomes slower, so the combustion reaction rate also becomes slower. Therefore, the smaller the solid particle diameter, the faster the oxygen diffusion rate, the faster the combustion rate, and as a result, the carbonaceous thermal energy recovery efficiency increases. That is, literature (RGMallon etc.Quarterly of the
According to Colorado School of Mines, 71(4)309 (1976)), oil shale (produced in Colorado) with a particle size of 73 mm was burned at 538°C by supplying gas with an oxygen concentration of 0.114 kg/ ^m3. In this case, it takes 3 hours to burn 30wt% of carbon. On the other hand, if the particle size is reduced to about 10 mm, the combustion time will be reduced to about 1/5 under the above conditions. Therefore, the device shape can also be made smaller. Therefore, the invention disclosed in JP-A-57-1781 is more advantageous in terms of shortening the time required for the combustion process and increasing the thermal energy recovery efficiency. However, a lot of power is required to crush the raw oil shale into small particle sizes before supplying it to the preheating and carbonization steps. Therefore, if the lumps that have cracked during the preheating and carbonization processes are crushed into smaller particles,
The required power is reduced. For example, if we compare the amount of work when crushing 100mm of oil siere raw material into small particle size of 10mmφ and the case where the particles crushed to 50 or 30mmφ in the drying/carbonization process are further crushed to 10mmφ, the amount of work in the former case is On the other hand, the workload of the latter can be reduced to about 50 to 70% (Japanese Patent Laid-Open No. 19385-1985). Therefore, the method and apparatus according to the present invention can significantly reduce the amount of work compared to conventional methods. Moreover, the time required for the preheating/carbonization process and the thermal energy utilization efficiency are not much different from those in the case of using the invention of Japanese Patent Application Laid-open No. 1781/1981. Therefore, as proposed in the present invention, after passing through the carbonization process, the oil siere lumps are transferred to the pulverization process and pulverized to reduce the particle size and adjust the particle size to be almost uniform, and combustion using a fluidized bed. It has been found that, when combined with a cooling step, a preferable carbonization method that combines the advantages of both inventions can be obtained. That is, the present invention provides (1) a method for treating oil sierre, in which the oil sierre agglomerates are carbonized, the carbonized product is recovered, and the remaining granules are burned to recover heat;
A non-oxidizing high-temperature heated gas is passed through from the top to the bottom while oil sierre agglomerates with irregular particle sizes are moved in a horizontally moving bed, and the agglomerates are carbonized at 300 to 900°C to recover the product. Next, the residual agglomerates are crushed and classified to a particle size suitable for fluidized bed combustion, and then transferred to a fluidized bed where they are fluidized by an oxygen-containing gas flow to burn the combustibles in the residual agglomerates and release the heat. A method for processing oil sierre, comprising: (2) carbonizing oil sierre agglomerates and recovering a carbonized product;
In the oil siel processing method, which recovers heat by burning residual granules, non-oxidizing high-temperature heated gas is passed through from above to below while oil sier granules with irregular particle sizes are moved in a horizontally moving bed. The agglomerates are carbonized at 300 to 900°C to recover the product together with non-oxidizing gas, and the remaining agglomerates are crushed and classified to a particle size suitable for fluidized bed combustion, and then transferred to a fluidized bed. The residual agglomerates are fluidized by an oxygen-containing gas flow to burn the combustibles in the residual agglomerates, and the residual agglomerates after combustion are transferred to a fluidized bed for heat recovery and fluidized by a non-oxidizing gas, and the non-oxidizing gas is heating and exchanging the heated non-oxidizing gas with the combustion gas from the combustion fluidized bed to produce a high-temperature heated gas, and flowing the non-oxidizing high-temperature heated gas through the horizontally moving bed. (3) A method for treating oil shale, characterized by carbonizing the product; (2) In the oil sierre processing method described in (4) and the oil sierre processing apparatus comprising an oil sierre agglomerate carbonization device and an oil sierre treatment device having a combustion device for residual granules after carbonization, the carbonization device has a particle size A moving grid for horizontally moving irregular oil siere grain agglomerates, a wind box disposed opposite to each other so as to sandwich the moving layer of the grain agglomerates, and a non-oxidizing high-temperature heating device connected above the wind box. The pulverizer is equipped with a gas supply pipe, a carbonization product collection pipe connected to the lower part of the same, and a discharge pipe for residual oil siere agglomerates provided at the discharge end of the moving grid, and is also equipped with a classification function. The above-mentioned exhaust pipe is connected to the apparatus, and the above-mentioned combustion apparatus is a combustion tower of a fluidized bed type, and the residual granule agglomerates discharged from the above-mentioned crushing apparatus are introduced into the middle lower part of the fluidized bed. A lump inlet pipe, a discharge pipe connected to the middle upper part of the fluidized bed for discharging residual granules after combustion, a fluidizing gas introduction pipe for introducing oxygen-containing gas into the lower part of the fluidized bed, This is an oil siel processing apparatus characterized by having a combustion gas recovery pipe connected to the upper part of the bed. The pulverized particle size varies depending on the physical properties of the oil siere, but is preferably within the range of about 0.1 to 10 mm in order to form a fluidized bed state. Next, an example of an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 shows a movable grating device called a circular grate or straight grate,
FIG. 1 shows a system diagram of an embodiment of the present invention that combines a sieving device, a fluidized bed device, and a heating furnace. The oil siel layer 2 loaded on the moving grid 1 moves through the carbonization section A divided by the partition walls x and y, and is exposed to the gas flow supplied to each section to be preheated, dried, and carbonized. That is, in FIG. 1, on the left side of the preheating/carbonization section A, an oil siel supply device (not shown) is used to load crushed oil shale onto a moving grid 1 to form an oil siel layer 2. As the moving grid 1 moves, the layer 2 first enters the preheating/carbonization section A;
A part of the carbonized product gas obtained by cooling and separating the carbonized product generated in the manner described below is transferred to the heating furnace F.
and is carbonized by exposure to a heated gas stream supplied from line 19. The gas that has flown out of the preheating/carbonization section A via line 3 passes through an oil quencher J and a heat exchanger K to a gas-liquid separator L, in order to entrain the carbonization product.
The produced gas is separated into produced oil and water, and the produced oil and water are further separated from water by a gas-liquid separator G.
Separated water is discharged from the system through line 5. on the other hand,
A part of the produced oil passes through line 7 and is circulated and used as circulating oil in quencher J via circulation pump M, and the rest is extracted out of the system via line 8 as product oil. In addition, the produced gas separated by the gas-liquid separator L is sucked into the blower N, and part of it is supplied to the cooling tower E through line 9 as cooling gas, and part of it is supplied as fuel gas to heating furnace F through line 10. However, the remainder is extracted from the system through line 11 as product gas. Oil siere layer 2 carbonized in carbonization section A
is supplied to the pulverizer C, and after being pulverized to the particle size necessary to form a fluidized bed in the next combustion tower D, it is passed through the downcomer pipe C-1 to the middle lower part of the combustion tower D. Supplied. The solid particles of oil siel supplied to the combustion tower D are maintained in a fluidized bed state by the oxygen-containing gas fed from the lower part of the combustion tower D through the line 15, and the solid particles are kept in a fluidized bed state, with the carbonaceous material in the solid particles being the main component. The combustible content is combusted, and the combustion exhaust gas is sent to combustion tower D.
It is discharged from the upper part via line 16 and fed into the lower part of the heating furnace F. The oxygen-containing gas sent to the combustion tower D from line 15 is sucked from line 12 by blower P, preheated by heat exchanger K, passed through line 13, and indirectly heated by heating furnace F (line 14). is used. Further, a part of the air may be used as combustion air for the heating furnace F through the line 15'. The solid particles after burning the combustibles in the combustion tower D are:
The downcomer pipe D-1 installed in the middle upper part of the combustion tower D is transferred to the middle lower part of the cooling tower E mainly by its own weight. (Part of the gas produced by carbonization)
The solid particles form a fluidized bed state and are cooled to approximately 100 to 150 degrees Celsius by transferring the sensible heat held by the solid particles to the cooling gas, after which they are disposed of through the outlet in the middle upper part via line E-1. It is discharged from the system as a solid. In the heating furnace F, the amount of heat generated by combusting a part of the carbonized product gas supplied from the line 10 is transferred to the exhaust gas discharged from the upper part of the cooling tower E through the line 18, so that the gas is heated to a high temperature. Cooling tower D exhaust gas is supplied from line 19 as heating gas to the preheating/carbonization section A. Combustion gas from heating furnace F is transferred to line 1 at heat exchanger Q.
After the sensible heat possessed by the gas containing oxygen is used to preheat the oxygen-containing gas flowing through line 20, it is discharged to the outside of the system through line 20. As described above, it is desirable to recirculate and use a part of the carbonization product gas as the cooling gas for the cooling tower E (heating gas for the preheating/carbonization section A). As mentioned above, this method recycles the carbonized gas that does not contain oxygen as the heating gas in the carbonized distillation section A, so combustion of the gas and oil does not occur, so high quality product gas and oil can be recovered. be able to. The optimum temperature range in each section differs depending on the physical properties of the oil siere, but the carbonization section A shown in the method shown in Figure 1 is 300 to 900℃ (preferably about 350 to 750℃), and the combustion tower D is 500 to 1100℃ ( Preferably 700~
900°C), and cooling tower E preferably has a temperature range of about 100 to 200°C. The oxygen-containing gas fed into the combustion tower D may be pure oxygen gas, but air is generally used as described above. Further, combustion exhaust gas containing residual oxygen may also be used for circulation. In the embodiment shown in FIG. 1, the crushing device C is shown connected to the moving grid device and the combustion tower D.
It may be a separate device. When these devices are connected, solid particles can be processed at high temperatures, so no heat is released, resulting in a device with high thermal efficiency. On the other hand, in the case of a connected structure, the crushing device C must be able to withstand high temperatures, but if it is a separate device, low-temperature processing becomes possible. The pulverizer C not only pulverizes the chunks of oil siel into small particles, but also converts the pulverized solid particles into solid particles in the particle size range necessary to form a fluidized bed state in the next combustion tower D. Preferably, it also has the function of classifying. As explained above, the method of the present invention uses gas heated with an indirect heater, that is, high-grade heat, only for the carbonization of hydrocarbon compounds, which is the original purpose of oil siel carbonization, and a large amount of effective heat is used. It is easy to understand that the present invention is an excellent method for recovering oil from oil shale, since it is possible to recover more effective heat in a shorter time and more efficiently from waste solids containing carbonaceous components. . The first example used to explain the above example
The shape of the device, the joining position of the pipes, etc. shown in the figures are not restricted to the drawings, and may be any other shapes as long as they do not depart from the spirit of the present invention.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of an embodiment of the present invention.

Claims (1)

[Claims] 1. In a method for treating oil sierre, in which oil sierre granules are carbonized, the carbonized product is recovered, and the remaining granules are burned to recover heat, oil sierre granules with irregular particle sizes are collected. While moving in a horizontally moving bed, non-oxidizing high-temperature heated gas is passed through from above to below, and the agglomerates are carbonized at 300 to 900°C to recover the product, and then the remaining agglomerates are subjected to fluidized bed combustion. An oil siere characterized by pulverizing and classifying the particles to a suitable particle size, transferring them to a fluidized bed, fluidizing them with an oxygen-containing gas flow, burning the combustibles in the remaining granules, and recovering the heat. processing method. 2. In an oil sierre treatment method in which oil sierre agglomerates are carbonized, the carbonized product is recovered, and the remaining granules are burned to recover heat, oil sierre granules with irregular particle sizes are moved in a horizontally moving bed. In the meantime, non-oxidizing high-temperature heated gas is passed through from above to below, and the agglomerates are carbonized at 300 to 900°C to recover the product together with the non-oxidizing gas.Then, the remaining agglomerates are subjected to fluidized bed combustion. After pulverizing and classifying to a suitable particle size, it is transferred to a fluidized bed and fluidized by an oxygen-containing gas flow.
Burn the combustibles in the residual agglomerates, transfer the residual agglomerates after combustion to a fluidized bed for heat recovery, fluidize them with non-oxidizing gas, heat the non-oxidizing gas, and produce heated non-oxidizing gas. A high-temperature heated gas is produced by exchanging heat with combustion gas from the combustion fluidized bed, and the non-oxidizing high-temperature heated gas is carbonized by flowing through the horizontally moving bed. Processing method. 3. The method for treating oil shale according to claim 2, characterized in that a part of the carbonized gas recovered by gas-liquid separation of the product from the carbonized distillation step is used as the non-oxidizing gas. 4. In an oil sierre processing device having a carbonization device for oil sierre agglomerates and a combustion device for residual granules after the carbonization, the carbonization device is configured to horizontally move oil sierre agglomerates having irregular particle sizes. A moving grid, a wind box facing each other so as to sandwich the moving bed of the granules, a non-oxidizing high temperature heating gas supply pipe connected above the wind box, and a carbonization product supply pipe connected below the wind box. It has a recovery pipe and a discharge pipe for residual granules of oil siere provided at the discharge end of the moving grid, and the discharge pipe is connected to a crushing device equipped with a classification function, and the combustion device , a fluidized bed type combustion tower, which is connected to a residual agglomerate introduction pipe for introducing the residual agglomerates discharged from the pulverizer into the middle lower part of the fluidized bed, and to the middle upper part of the fluidized bed. The method includes a discharge pipe for discharging residual agglomerates after combustion, a fluidizing gas introduction pipe for introducing oxygen-containing gas into the lower part of the fluidized bed, and a combustion gas recovery pipe connected to the upper part of the fluidized bed. Characteristic oil siel processing equipment.