JP4875473B2 - Gasification gas purification method - Google Patents

Description

The present invention, such as organic waste or coal, such as waste plastics, biomass solid organics relates purification of how the resultant gasified gas by thermal decomposition, particularly of the gasification gas using an activated carbon adsorption device Kiyoshi of how on.

  In recent years, effective use of energy has been attracting attention as part of global environmental conservation, especially prevention of global warming. Organic waste is a method for effectively using energy of organic waste such as waste plastic and biomass. So-called gasification, which obtains a combustible gas by pyrolyzing the gas, is attracting attention.

  However, combustible gas obtained by gasification, that is, gasification gas contains dioxins caused by chlorine contained in organic waste, so when using gasification gas, dioxins are removed. is required. In addition to dioxins, organic waste gasification gases include high-boiling hydrocarbon compounds that are liquid or solid at room temperature and normal pressure, such as tar and light oil (in the present specification, simply referred to as “high-boiling hydrocarbon compounds”). Here, the boiling point of the “high-boiling hydrocarbon compound” is approximately 60 ° C. or higher.). These high boiling hydrocarbon compounds have a high vapor pressure even at temperatures below the boiling point and are difficult to remove by cooling, etc., and the high boiling hydrocarbon compounds remaining in the gas condense when the temperature of the gasification gas decreases. In addition, it may cause equipment trouble by adhering to the gas piping and its ancillary equipment. Therefore, it is necessary to remove from gasification gas with dioxins.

  Conventionally, as a technique for removing dioxins in a gas, for example, as disclosed in Patent Document 1, a technique in which dioxins are decomposed by a catalyst layer and the remaining dioxins are adsorbed by an activated carbon adsorption layer. Is established. However, the technique of this patent document 1 is mainly intended for treating the combustion exhaust gas after burning a combustible substance, and when the technique of patent document 1 is applied to the treatment of gasification gas of organic waste. In the catalyst layer, hydrocarbon gases other than dioxins are also decomposed and soot is generated. Moreover, in the activated carbon adsorption layer, the above-mentioned high boiling point hydrocarbon compounds are adsorbed in addition to dioxins, and the activity of the activated carbon cannot be maintained. In order to sustain it, it is necessary to always use new activated carbon, which increases operating costs.

  Further, Patent Document 2 is provided with a dust collector such as a bag filter, in which powdered activated carbon is blown before the activated carbon layer is formed on the filter cloth surface of the bag filter, and the dioxins are adsorbed on the activated carbon. This technique is disclosed. However, even in the technique of this Patent Document 2, when this is applied to the treatment of gasification gas of organic waste, troubles such as clogging occur due to the above-mentioned high boiling point hydrocarbon compound contained in the gasification gas, Stable operation cannot be continued.

  On the other hand, Patent Document 3 and Patent Document 4 disclose a purification technique using activated carbon to remove hydrocarbons such as solvents and light oil in exhaust gas. However, when the light oil contained in the gasification gas of organic waste is removed by activated carbon, it is difficult to control gas purification because the raw material of the gas is waste and the properties of the raw material are not stable. Since the gasified gas contains not only light oil but also tar, if the gas containing tar is purified by activated carbon, the tar is not easily separated from the activated carbon, and the life of the activated carbon is shortened.

  Patent Documents 5 and 6 disclose a technique for purifying biomass gas (gasification gas) obtained by pyrolyzing biomass using activated carbon. However, with this technology, it is possible to adsorb and remove tar components having a high gas treatment temperature and a high molecular weight and a high boiling point, but they have a low molecular weight, a relatively low boiling point, a high volatility, and a normal temperature. It is impossible to adsorb and remove liquid hydrocarbon compounds, so-called light oil components, under pressure. Light oil is cooled in the piping and drained when using gas. Since this drain is a highly volatile flammable oil, it is difficult to handle. In addition, in the case of gasification gas using raw materials other than biomass with uniform properties, the generation amount and properties of tar may change, the activated carbon adsorption layer may be clogged, and light oil may flow to the gas utilization facility, causing problems. There is sex. In particular, when fossil fuels such as waste plastics and coal, or solid organic substances made from fossil fuels are gasified, the amount of tar and light oil is large, and the above-mentioned technique cannot perform sufficient purification. .

  As described above, various techniques for purifying gas using activated carbon have been proposed in the past. However, when purifying gasification gas containing a high boiling point hydrocarbon compound, particularly tar and light oil, the above-mentioned problems are required. However, gasification gas purification technology using activated carbon has not been established.

  On the other hand, a gasification gas purification technique that does not use activated carbon has also been proposed. For example, Patent Document 7 discloses a technology for reducing tar content and light oil content in gasified gas by gasification of organic waste, reaction with oxygen and water vapor, and reforming reaction at a high temperature of about 1100 ° C. Proposed. However, gas purification technology using such a reforming reaction requires partial combustion of the gasified gas in order to obtain a heat source required for the reforming reaction. There is a problem of lowering. In addition, the production of oxygen used for the reforming reaction requires a lot of energy, and the total energy required for waste treatment becomes too large.

  As another gas cleaning technique, there is a technique of cleaning a gas with oil at a low temperature to remove a tar content and a light oil content in the gas, as seen in a course furnace gas purification technique. However, with this technique, energy is required to obtain a cold heat source for cleaning at low temperatures. Moreover, advanced treatment is required for the waste water after washing, and further, a step of regenerating oil and the like is required, and facilities such as treatment of gas generated at the time of regeneration tend to be complicated. Further, dioxins cannot be removed by gas cleaning.

  Thus, in order to purify the gas by simultaneously removing high boiling point hydrocarbon compounds such as dioxins and tar content, light oil content, etc. in the gas, it is also useful and simple to dry-process using activated carbon, Establishment of gasification gas purification technology using activated carbon is desired.

On the other hand, when an organic substance is thermally decomposed to obtain a combustible gasification gas, it is desirable to keep hydrocarbon gas such as methane and keep gas calorie high when using the gasification gas. In this case, however, tar and light oil are by-produced and hinder gas utilization. Therefore, establishment of the purification technology which removes the tar content and light oil content in gasification gas also from this point is desired.
Japanese Patent Laid-Open No. 2003-112012 JP-A-11-230529 JP-A-9-215908 JP 2005-66503 A JP 2006-16469 A JP 2006-16470 A JP 2004-238535 A

  The problem to be solved by the present invention is to establish a purification technology for gasification gas using activated carbon and obtain a usable high calorie gas.

Specifically, to provide a purification of how the gasification gas that can dioxins in the gasification gas and high-boiling hydrocarbon compounds efficiently removed, and thereby long-lasting the gas purification capability It is in.

One aspect of the present invention is to adsorb and remove dioxins in gasification gas obtained by pyrolyzing organic waste or solid organic matter such as coal and high-boiling hydrocarbon compounds that are liquid or solid at normal temperature and pressure. For the activated carbon adsorption layer that has two or more activated carbon adsorption layers in parallel to operate and switches between the two or more activated carbon adsorption layers and is not used for adsorption removal, A gasification gas purification device that maintains adsorption performance by removing adsorbed substances by passing a gas of 100 ° C. or higher that does not contain oxygen, such as in the gasification gas flow direction before the gasification gas flow direction. mist moisture, tar of the high-boiling hydrocarbon compounds, dioxins and solid dust provided capable of adsorbing the adsorption device, gasification gas provided the activated carbon adsorption apparatus downstream of the suction device In the purification method of the gasification gas by purifying apparatus, at the front stage of the adsorption device, mainly adsorbed mist moisture in the gasification gas, tar of the high-boiling hydrocarbon compounds, the dust of dioxins and solid In the latter-stage activated carbon-type adsorption device, mainly the light oil components other than tar and dioxin residues in the high-boiling hydrocarbon compounds are adsorbed and removed to regenerate the adsorption layer of the former adsorption device. It is characterized by using a light oil adsorbed by a subsequent activated carbon adsorption device . In another aspect of the present invention, an inorganic material such as a ceramic ball is used as an adsorbent for the adsorbing layer in the adsorbing device in the previous stage. Heat treatment is performed in a gasification furnace that thermally decomposes and gasifies solid organic matter such as waste or coal, or a combustion furnace that supplies heat to the gasification furnace.

  In the present invention, waste plastic is typically gasified as organic waste, or coal is gasified as solid organic matter.

  The organic waste or solid organic gasification gas contains dioxins and a high-boiling hydrocarbon compound. High boiling point hydrocarbon compounds include tar components such as naphthalene and anthracene (polymer hydrocarbon compounds having 10 or more carbon atoms) and light oil components such as benzene, toluene and xylene (low carbon number of less than 10). Molecular hydrocarbon compounds). These dioxins and high-boiling hydrocarbon compounds need to be removed for effective utilization of the gasification gas. However, if such a gasification gas is suddenly passed through an activated carbon adsorption device, tar and solid dust in the gasification gas are adsorbed on the activated carbon adsorption layer, and this reduces the light oil adsorption capacity and also helps in regeneration. The required energy increases. Therefore, in the present invention, another adsorption device is provided in the previous stage of the activated carbon type adsorption device, and in the previous adsorption device, the mist-like water in the gasification gas, the tar content of the high-boiling hydrocarbon compound, dioxin Then, adsorbing and removing the soot and solid soot are carried out, and thereafter, the activated carbon-type adsorbing device in the subsequent stage is used to adsorb and remove light oil components other than tar and residual dioxins from the high boiling point hydrocarbon compound. In other words, in the present invention, two stages of adsorption devices are provided in series and the functions are divided so that the efficiency of gasification gas purification is improved and the gas purification capacity is maintained for a long period of time.

  In order to make the purification of gasification gas by such a two-stage adsorption device more efficient, a cooling device for cooling the gasification gas is provided in the front stage of the front stage adsorption apparatus, and the front stage adsorption apparatus and the rear stage adsorption device are provided. A heating device that heats the gasification gas is installed between the activated carbon type adsorption device, and in the previous adsorption device, the mist-like water in the gasification gas, the tar content of the high-boiling hydrocarbon compound, dioxin It is preferable that the gasification gas is heated after passing the adsorbed and solid soot and removed, and passed through an activated carbon-type adsorbing device at a later stage. That is, when the gasification gas is passed through the preceding adsorption device, the temperature is set low (about 10 to 40 ° C.), and the condensation of the mist-like moisture and tar is promoted to adsorb the adsorption device in the previous stage. Increasing efficiency, and then heating to about 30 to 70 ° C. to lower the relative humidity of the gasification gas and suppressing draining of the gasification gas, thereby increasing the adsorption efficiency of the latter activated carbon type adsorption device, The activity of activated carbon can be maintained for a long time.

  In the present invention, a dust collector such as an electric dust collector may be provided in the front stage of the preceding stage adsorption device, and the gasification gas may be passed through the dust collector such as an electric dust collector before passing through the preceding stage adsorption device. By adopting such a configuration, particles having a large molecular weight such as naphthalene, anthracene, phenanthrene, and pyrene can be removed at the front stage of the front stage adsorption apparatus, and a decrease in the adsorption capacity of the front stage adsorption apparatus can be suppressed. it can.

  As the adsorbent for the adsorbing layer in the preceding adsorption device, an inorganic material such as activated carbon or ceramic balls can be used. When using activated carbon, it is preferable to select the activated carbon having pores larger than the pores of the activated carbon used in the activated carbon-type adsorption device in the subsequent stage. As a result, the tar content in the high-boiling hydrocarbon compound can be removed preferentially, and the performance deterioration due to the light oil content can be suppressed. On the other hand, when an inorganic material such as a ceramic ball is used as the adsorbent for the adsorption layer in the adsorption apparatus in the previous stage, cleaning for regeneration and the like are facilitated, and energy required for regeneration can be reduced.

  Moreover, iron oxide can be included in the adsorbent of the adsorption layer in the adsorption apparatus in the previous stage. Hydrogen chloride gas generated when organic waste is gasified has high solubility in water and can be easily removed by washing treatment, but sulfur such as hydrogen sulfide is difficult to remove by washing. Moreover, although adsorption | suction to activated carbon is possible, it is difficult to make it detach | leave and causes deterioration of activated carbon. Therefore, the sulfur content contained in gasification gas can be efficiently adsorbed and removed by including iron oxide in the adsorbent.

  In the present invention, the adsorption layer of the preceding adsorption device and the activated carbon adsorption layer of the latter activated carbon type adsorption device need to be regenerated at the time of breakthrough or periodically, and normally steam is used for the regeneration. For the regeneration of the adsorption layer of the preceding adsorption device, light oil adsorbed by the latter activated carbon adsorption device can be used. The adsorption apparatus in the previous stage is intended to adsorb organic compounds having a relatively large molecular weight such as tar. Since organic compounds such as tar are highly soluble in light oils (organic solvents) such as benzene, the light oil adsorbed by the activated carbon adsorber at the latter stage is collected and passed to the adsorption layer of the former adsorber. Thus, the tar content adsorbed on the adsorption layer of the preceding adsorption device can be dissolved in the light oil component and easily separated from the adsorption layer. Further, since the amount of steam used can be reduced, energy loss can be reduced.

  Also, when using inorganic materials such as ceramic balls as the adsorbent for the adsorbing layer in the pre-stage adsorbing device, the adsorbent is taken out from the adsorbing layer and pyrolyzed for organic waste or solid organic matter such as coal. Then, it can be regenerated by heat treatment in a gasification furnace for gasification or a combustion furnace for supplying heat to the gasification furnace. Thus, by performing the regeneration process by the heat treatment in the gasification furnace or the combustion furnace associated with the equipment, the amount of steam used for the regeneration can be reduced or zero, and the energy loss is reduced. Further, organic components such as tar and dust adhering to the adsorbent can be effectively used as fuel for the gasification furnace or combustion furnace. In addition, since the adsorbent is usually heat-treated in the gasification furnace or combustion furnace and then discharged together with the incineration ash etc. of the gasification furnace or combustion furnace, the adsorbent is separated and recovered by the ash discharge mechanism. It is preferable to provide a recovery mechanism. As this recovery mechanism, a vibrating sieve or a wind power sorter can be used.

  According to the present invention, in the former stage adsorption device, the mist-like moisture in the gasification gas, the high-boiling hydrocarbon compound, the tar content, dioxins and solid soot are adsorbed and removed, and then the latter stage The activated carbon adsorber absorbs and removes light oil components other than tar and dioxin residues from high-boiling hydrocarbon compounds, enabling efficient purification of gasification gas and long-term gas purification capacity. Can be made.

  In addition, high boiling point hydrocarbon compounds (tar content and light oil content) in gasification gas can be removed stably, enabling operation with lower gasification and reforming temperatures, and stable high calorie gasification gas. Can be obtained. In addition, it is possible to reduce the energy, oxygen amount, and the like necessary for increasing the gas temperature, and it is possible to obtain a high calorie gasified gas at a lower cost.

Embodiments of the present invention will be described below based on examples shown in the drawings. In addition, what implements a part of this invention below is demonstrated as an Example.

  FIG. 1 is an apparatus configuration diagram showing a first embodiment of the present invention.

  In FIG. 1, in the purification process line of the gasification gas obtained in the gasification furnace 1 for gasifying organic waste, an adsorption device 2 is arranged in the upstream of the gasification gas flow direction, and the activated carbon is in the subsequent stage. A type adsorption device 3 is arranged. The former adsorption device 2 has two activated carbon adsorption layers 2a and 2b in parallel, and the latter activated carbon adsorption device 3 also has two activated carbon adsorption layers 3a and 3b in parallel. The activated carbon adsorption layers 2a and 2b of the adsorption device 2 may contain about 20 to 100% by mass of iron oxide in order to efficiently adsorb sulfur.

  As the gasification furnace 1, various furnaces such as a shaft furnace, a rotary kiln furnace, a fluidized bed furnace, a fixed bed furnace, and a jet flow furnace can be used. Further, the heating method of the gasification furnace 1 may be either a partial combustion method in which a part of the generated gasification gas is burned and used as a heat source, or an external heat method using an external heat source.

  The gasification gas obtained in the gasification furnace 1 passes through the gasification gas supply main pipe 4, and then passes through the gasification gas supply branch pipes 5a and 5b leading to the activated carbon adsorption layers 2a and 2b of the adsorption apparatus 2, and then the adsorption apparatus It introduce | transduces into the activated carbon adsorption layer 2a, 2b of 2 from the lower part.

  When the gasification gas is introduced into the activated carbon adsorption layers 2a, 2b of the adsorption device 2, the mist-like moisture in the gasification gas, a high-boiling hydrocarbon compound, particularly a high tar content with a boiling point of 150 ° C. or higher, Dioxins and solid dust are adsorbed and removed by the activated carbon in the activated carbon adsorption layers 2a and 2b. Thereafter, the gasified gas is discharged from the gasified gas discharge branch pipes 6a and 6b connected to the upper portions of the activated carbon adsorption layers 2a and 2b, and merged into the gasified gas transport main pipe 7 and further activated carbon adsorption of the activated carbon type adsorption device 3 The gas passes through the gasified gas transfer branch pipes 8a and 8b leading to the layers 3a and 3b, and is introduced into the activated carbon adsorption layers 3a and 3b of the activated carbon adsorption device 3 from below.

  When the gasification gas is introduced into the activated carbon adsorption layers 3a and 3b of the activated carbon adsorption device 3, the light oil component and the residual dioxins mainly from the high boiling point hydrocarbon compound in the gasification gas are the activated carbon adsorption layer 3a, It is adsorbed and removed by the activated carbon in 3b. Thereafter, the gasification gas is discharged from the gasification gas discharge branch pipes 9a and 9b connected to the upper portions of the activated carbon adsorption layers 3a and 3b, merges into the gasification gas discharge main pipe 10, and is conveyed to the gas utilization facility 11.

  Specific uses of gasified gas include fuel for industrial furnaces such as heating furnaces and coke ovens, fuel for gas engines and gas turbines, boiler fuel, fuel for hot stove furnaces, and the like.

  As described above, in the present invention, the adsorption device is provided in two stages in series, and the mist-like moisture in the gasification gas, the tar content, the dioxins and the solid dust in the high-boiling hydrocarbon compound in the adsorption device 2 in the previous stage. By adsorbing and removing light oil components other than tar and residual dioxins from the high boiling point hydrocarbon compound by the activated carbon adsorption device 2 in the subsequent stage, the gasification gas purification efficiency is improved. At the same time, the gas purification capacity is maintained for a long time.

  In the present embodiment, the activated carbon used in the preceding-stage activated carbon adsorption layers 2a, 2b and the latter-stage activated carbon adsorption layers 3a, 3b can be changed to a high size suitable for adsorption of tar content by changing the size of the pores. For molecular adsorption, the latter one used for low molecular adsorption suitable for light oil adsorption.

  In this embodiment, the gasification gas supply branch pipes 5a and 5b and the gasification gas discharge branch pipes 6a and 6b associated with the adsorption device 2 in the preceding stage are provided with on-off valves 12a and 12b and on-off valves 13a and 13b, respectively. ing. In addition, each of the activated carbon adsorption layers 2a and 2b is connected to steam supply branch pipes 14a and 14b branched from the steam supply main pipe 14 at the upper part, and connected to waste steam discharge branch pipes 15a and 15b at the lower part. The steam supply branch pipes 14a and 14b and the waste steam discharge branch pipes 15a and 15b are provided with on-off valves 16a and 16b and on-off valves 17a and 17b, respectively.

  The latter-stage activated carbon adsorption device 3 has the same configuration, and the gasification gas transport branch pipes 8a and 8b and the gasification gas discharge branch pipes 9a and 9b associated with the activated carbon adsorption device 3 are provided with on-off valves 18a and 18b, respectively. And on-off valves 19a and 19b are provided. In addition, each of the activated carbon adsorption layers 3a and 3b is connected to steam supply branch pipes 20a and 20b branched from the steam supply main pipe 20 at the upper part and connected to waste steam discharge branch pipes 21a and 21b at the lower part. The steam supply branch pipes 20a and 20b and the waste steam discharge branch pipes 21a and 21b are provided with on-off valves 22a and 22b and on-off valves 23a and 23b, respectively.

  By adopting such a configuration, in this embodiment, when the adsorption capacity of any activated carbon adsorption layer in the preceding adsorption device 2 or the activated carbon adsorption device 3 in the latter stage is reduced, The adsorbing ability can be recovered by shutting off the gas flow of the chemical gas and removing the adsorbed substance by passing the vapor and discharging it to the vapor side as waste vapor.

  For example, when the adsorption capacity of the activated carbon adsorption layer 2a of the adsorption device 2 is lowered, the on / off valve 12a of the gasification gas supply branch 5a and the on / off valve 13a of the gasification gas discharge branch 6a are closed and the steam supply branch 14a is closed. The on-off valve 16a and the on-off valve 17a of the waste steam discharge branch 15a are opened. As a result, the gasification gas passing through the activated carbon adsorption layer 2a is blocked, and steam is passed instead. The tar and the like adsorbed on the activated carbon adsorption layer 2a are removed by this vapor and discharged as waste vapor to the vapor side, so that the adsorption capability of the activated carbon adsorption layer 2a is recovered. The waste steam is discharged from the lower part of the activated carbon adsorption layer 2a through the waste steam discharge branch 15a, joined to the exhaust steam discharge main pipe 15, and then transported to a predetermined place. At the same time, the gasification gas can be continuously processed by opening the on-off valve 12b of the gasification gas supply branch 5b and the on-off valve 13b of the gasification gas discharge branch 6b.

  Further, when the adsorption capacity of the activated carbon adsorption layer 3a of the activated carbon adsorption device 3 is lowered, the on / off valve 18a of the gasification gas transfer branch 8a and the on / off valve 19a of the gasification gas discharge branch 9a are closed and steam is supplied. The on-off valve 22a of the branch pipe 20a and the on-off valve 23a of the waste steam discharge branch pipe 21a are opened. As a result, the gasification gas passing through the activated carbon adsorption layer 3a is blocked and steam is passed instead. The tar and the like adsorbed on the activated carbon adsorption layer 3a are removed by this vapor and discharged to the vapor side as waste vapor, so that the adsorption capability of the activated carbon adsorption layer 3a is recovered. The waste steam is discharged from the lower part of the activated carbon adsorption layer 3a through the waste steam discharge branch pipe 21a, joined to the exhaust steam discharge main pipe 21, and then transported to a predetermined place. At the same time, by opening the on-off valve 18b of the gasified gas transfer branch 8b and the on-off valve 19b of the gasified gas discharge branch 9b, the gasification gas can be processed continuously.

  As described above, in this embodiment, the activated carbon adsorption layer having a reduced adsorption capacity can be regenerated without stopping the operation of the apparatus, and the gasification gas purification process is continuously performed while maintaining a certain adsorption capacity. It can be performed.

  In addition, it is preferable to make the temperature of the vapor | steam used for reproduction | regeneration of an activated carbon adsorption layer into the range of 150-400 degreeC. When the temperature of the steam is as low as about 100 ° C., among the high-boiling hydrocarbon compounds adsorbed on the activated carbon in the activated carbon adsorption layer, for light oils such as benzene, toluene, xylene, etc. with a low molecular weight and a relatively low boiling point Although it is possible to desorb, tar components such as naphthalene and anthracene having a molecular weight of 100 or more and a high boiling point are difficult to desorb.

  In this embodiment, steam is used to regenerate the activated carbon adsorption layer. However, the present invention is not limited to steam, and any gas can be used as long as it does not contain oxygen and is 100 ° C. or higher. Also in this case, the temperature of the gas used is preferably in the range of 150 to 400 ° C.

  FIG. 2 is an apparatus configuration diagram showing a second embodiment of the present invention. In this embodiment, in the apparatus configuration of the first embodiment shown in FIG. 1, a gas cooler 24a is provided as a cooling device for cooling the gasification gas in the preceding stage of the preceding adsorption apparatus 2, and the preceding adsorption apparatus 2 and A gas heater 24b is provided as a heating device for heating the gasified gas between the latter activated carbon type adsorption device 3.

  In this embodiment, when the gasification gas is passed through the preceding adsorption device 2, the gasification gas is cooled by the gas cooler 24a before the gasification gas is set to a low temperature (about 10 to 40 ° C.). The adsorption efficiency of the adsorption device 3 in the previous stage is increased by promoting the condensation of the moisture and tar content, and then the gasified gas is heated to about 30 to 70 ° C. by the gas heater 24b and the relative humidity of the gasified gas is increased. By reducing the gasification gas and reducing the draining of the gasification gas, it is possible to increase the adsorption efficiency of the activated carbon type adsorption device 3 at the subsequent stage and to maintain the activity of the activated carbon for a long period of time.

  FIG. 3 is an apparatus configuration diagram showing a third embodiment of the present invention. In this embodiment, an electric dust collector 25 is provided as a dust collector in the front stage of the adsorption device 3. With this electrostatic precipitator 25, particles having a large molecular weight such as naphthalene can be removed in the previous stage of the adsorption device 3, and a decrease in adsorption capacity of the adsorption device 3 can be suppressed.

  The electric dust collector 25 may be either a dry type or a wet type, and the dust collector may be a cyclone, a filtration type or a scrubber type in addition to the electric dust collector 25. As shown in FIG. 3, gas treatment such as gas scrubbing with a water scrubber or an oil scrubber may be performed as a pretreatment before the electric dust collector 25.

  In this embodiment, the waste steam discharged during regeneration of the activated carbon adsorption layers 2a, 2b, 3a, 3b or the waste drain condensed with the waste steam is passed to the gasification furnace 1 through the waste steam discharge main 15. The heat is supplied to the combustion furnace 1a for supplying heat. As a result, the high-boiling point hydrocarbon compound contained in the waste steam or waste drain can be effectively used as a part of the fuel in the combustion furnace 1a, and the harmful substances such as the organic chlorine compound contained in the waste steam or waste drain are incinerated. It can be detoxified and released.

  FIG. 4 is an apparatus configuration diagram showing a fourth embodiment of the present invention. In this embodiment, the light oil adsorbed by the activated carbon adsorption device 3 is used for the regeneration of the activated carbon adsorption layers 2a and 2b of the adsorption device 2.

  Since the activated carbon adsorption device 3 mainly adsorbs light oil in the high boiling point hydrocarbon compound as described above, waste steam or waste steam discharged during regeneration of the activated carbon adsorption layers 3a and 3b of the activated carbon adsorption device 3 is reduced. Condensed waste drain contains a lot of light oil. In the present embodiment, waste steam or waste drain discharged during regeneration of the activated carbon adsorption layers 3a and 3b is collected and condensed in the recovery tank 26, and this is recovered from above when the activated carbon adsorption layers 2a and 2b of the adsorption device 2 are regenerated. I try to make it flow. The adsorber 2 mainly adsorbs the tar content of the high-boiling hydrocarbon compound, but since the tar content is highly soluble in the light oil, the tar is contained in the light oil by flowing waste drain containing the light oil. It is possible to easily regenerate the activated carbon adsorption layers 2a and 2b. As a result, it is not necessary to use steam to regenerate the activated carbon adsorption layers 2a and 2b, and energy loss can be reduced.

  In this embodiment, the waste drain discharged during the regeneration of the activated carbon adsorption layers 2a, 2b is recovered in the recovery tank 27, and this is recovered in the gasification furnace 1 or the combustion furnace 1a as in the third embodiment. I try to inject it as fuel.

  FIG. 5 is an apparatus configuration diagram showing a fifth embodiment of the present invention. In this embodiment, the adsorption layer of the adsorption device 2 is made of ceramic ball adsorption layers 2a 'and 2b' filled with ceramic balls as adsorbents.

  In this embodiment, when the ceramic ball adsorbing layers 2a ′ and 2b ′ are regenerated, the ceramic balls are extracted from the ceramic ball adsorbing layers 2a ′ and 2b ′ by the conveyer 28 and put into the gasification furnace 1 or the combustion furnace 1a. And regenerated by heat treatment. The ceramic balls are discharged together with the incinerated ash of the gasification furnace 1 or the combustion furnace 1a after being subjected to heat treatment. Thereafter, the ceramic balls discharged together with the incineration ash and the like are collected by the collection / separation device 29 and only the ceramic balls are separated. The ceramic balls are separated by the conveyor 30 by the ceramic ball adsorption layers 2a ′ and 2b ′. Returned to As the recovery / separation device 29, a vibration sieve or a wind power sorter can be used.

  Thus, in this embodiment, the regeneration of the ceramic ball adsorption layers 2a 'and 2b' is performed by heat treatment in the gasification furnace 1 or the combustion furnace 1a. Accordingly, it is not necessary to use steam to regenerate the ceramic ball adsorption layers 2a 'and 2b', and energy loss is reduced. Further, organic components such as tar and dust adhering to the ceramic ball can be effectively used as fuel for the gasification furnace 1 or the combustion furnace 1a.

  Further, in this embodiment, waste steam or waste drain discharged at the time of regeneration of the activated carbon adsorption layers 3a and 3b of the activated carbon adsorption device 3 is collected in the collection tank 26, and this is the same as in the previous third embodiment. The gasification furnace 1 or the combustion furnace 1a is blown as fuel.

  As mentioned above, in each Example, the purification method of gasification gas obtained by thermally decomposing organic waste was explained, but the purification method of gasification gas of the present invention is obtained by pyrolyzing organic waste. It can be applied not only to gasified gas produced, but also to gasified gas obtained by thermally decomposing solid organic matter such as coal, such as coke oven gas and coal gasified fuel gas.

BRIEF DESCRIPTION OF THE DRAWINGS It is an apparatus block diagram which shows 1st Example of this invention. It is an apparatus block diagram which shows 2nd Example of this invention. It is an apparatus block diagram which shows 3rd Example of this invention. It is an apparatus block diagram which shows 4th Example of this invention. It is an apparatus block diagram which shows 5th Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gasification furnace 1a Combustion furnace 2 Adsorber 2a, 2b Activated carbon adsorption layer 2a ', 2b' Ceramic ball adsorption layer 3 Activated carbon type adsorption device 3a, 3b Activated carbon adsorption layer 4 Gasification gas supply main 5a, 5b Gasification gas supply Branch pipes 6a, 6b Gasified gas discharge branch pipes 7 Gasified gas transfer main pipes 8a, 8b Gasified gas transfer branch pipes 9a, 9b Gasified gas discharge branch pipes 10 Gasified gas discharge main pipes 11 Gas utilization facilities 12a, 12b, 13a, 13b Open / close valve 14 Steam supply main 14a, 14b Steam supply branch 15 Waste steam discharge main 15a, 15b Waste steam discharge branch 16a, 16b, 17a, 17b, 18a, 18b, 19a, 19b Open / close valve 20 Steam supply main 20a, 20b Steam supply branch 21 Waste steam discharge main pipe 21a, 21b Waste steam discharge branch pipe 22a, 22b, 23a, 23b On-off valve 4a gas cooler 24b gas heater 25 extracts the electrostatic precipitator 26, 27 recovery tank 28 conveyor 29 collecting and separating device 30 conveyor

Claims (2)

Two or more dioxins in the gasification gas obtained by pyrolyzing organic waste or solid organic matter such as coal and two or more high-boiling hydrocarbon compounds that are liquid or solid at normal temperature and pressure are adsorbed and removed. An activated carbon adsorption device having an activated carbon adsorption layer provided in parallel, which is operated while switching between the two or more activated carbon adsorption layers, and which is not used for adsorption removal does not contain oxygen such as steam 100 A gasification gas purifying apparatus that removes substances adsorbed by passing a gas at a temperature higher than or equal to ℃ and maintains adsorption performance, wherein mist-like moisture in the gasification gas is disposed upstream of the gasification gas flow direction. tar out of boiling hydrocarbon compounds, capable of adsorbing the adsorption apparatus soot dioxins and solid provided, according to the purifying apparatus of gasification gas provided with the activated carbon adsorption apparatus downstream of the suction device In the purification method of the soot gas, the sorbed moisture in the gasification gas, mainly the mist-like moisture in the gasification gas, the tar content, the dioxins, and the solid soot in the high boiling hydrocarbon compound are adsorbed and removed. In the activated carbon type adsorption device of the above, mainly the light oil components other than tar content and residual dioxins of the high boiling point hydrocarbon compounds are adsorbed and removed, and the activated carbon type of the latter stage is used for the regeneration of the adsorption layer of the former stage adsorption device. A method for purifying gasification gas, comprising using light oil adsorbed by an adsorption device . Two or more dioxins in the gasification gas obtained by pyrolyzing organic waste or solid organic matter such as coal and two or more high-boiling hydrocarbon compounds that are liquid or solid at normal temperature and pressure are adsorbed and removed. An activated carbon adsorption device having an activated carbon adsorption layer provided in parallel, which is operated while switching between the two or more activated carbon adsorption layers, and which is not used for adsorption removal does not contain oxygen such as steam 100 A gasification gas purifying apparatus that removes substances adsorbed by passing a gas at a temperature higher than or equal to ℃ and maintains adsorption performance, wherein mist-like moisture in the gasification gas is disposed upstream of the gasification gas flow direction. By means of a gasification gas purifying device in which an adsorption device capable of adsorbing tar content, dioxins and solid soot among the boiling point hydrocarbon compounds is provided, and the activated carbon type adsorption device is provided at the subsequent stage of the adsorption device. In the purification method of the soot gas, the sorbed moisture in the gasification gas, mainly the mist-like moisture in the gasification gas, the tar content, the dioxins, and the solid soot in the high boiling hydrocarbon compound are adsorbed and removed. In the activated carbon type adsorber, the light oil components other than tar and dioxin residues are mainly adsorbed and removed from the high boiling point hydrocarbon compounds, and ceramic balls or the like are used as adsorbents in the adsorbing layer in the preceding adsorber. When regenerating this adsorption layer using an inorganic material, the adsorbent is taken out from the adsorption layer, and the organic waste or solid organic matter such as coal is pyrolyzed and gasified, or into a gasification furnace A method for purifying gasification gas, wherein the heat treatment is performed in a combustion furnace for supplying heat .

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