JP2008501368A - Treatment method for persistent organic pollutants - Google Patents

Abstract

  A low-cost, safe and reliable treatment that can reduce the burden of exhaust gas treatment by improving the decomposition efficiency of pollutants in the method of treating residual organic pollutants such as waste agricultural chemicals by indirect heat treatment method Provide a way to do. One aspect of the present invention relates to a method of treating persistent organic pollutants, the method comprising mixing organic pollutants, a solid medium, an alkaline agent, and a high boiling polar solvent. . Another aspect of the present invention is a method for treating persistent organic pollutants contained in a solid medium, comprising: an organic pollutant in a solid medium; an alkali agent; and a high-boiling polar solvent. The present invention relates to a method characterized by mixing.

Description

  The present invention relates to a method for treating harmful persistent organic pollutants. INDUSTRIAL APPLICABILITY The present invention is useful for the treatment of agricultural chemicals, particularly residual waste agricultural chemicals, and can be preferably applied to the decomposition treatment of organic chlorine-based or drin-based waste agricultural chemicals. It can also be applied to the decomposition process.

  It is known that some agricultural chemicals that have been banned in the past in Japan are buried underground in containers and remain toxic. These include BHC, chlordane, DDT, etc., designated by international conventions as persistent organic pollutants to be treated. As a method for treating these waste pesticides, incineration treatment can be considered as the simplest method. However, the incineration process generates a large amount of combustion exhaust gas and may generate a high concentration of harmful by-products. Therefore, there is a concern about the influence on the surrounding environment, and it is difficult to implement in practice. In addition, chemical treatment by liquid reaction has the advantage that it hardly emits exhaust gas and can be easily reprocessed even if the treatment is insufficient, but a dedicated treatment facility is required. .

  For these treatment methods, there has been proposed a method of treating organic pollutants by indirect heating by using a heating medium and mixing and heating the residual organic pollutants to be treated with the heating medium. This method has the advantage that the amount of exhaust gas can be reduced and an existing heating facility such as a rotary kiln heating furnace can be diverted. However, with this indirect heat treatment method, it is not possible to decompose all of the organic pollutants introduced into the heating furnace together with the heating medium, and some of them are transferred to exhaust gas without being decomposed. For this reason, it is necessary to further perform gas treatment for removing residual organic pollutants from the exhaust gas.

  In addition, a method for decomposing organic pollutants by reacting them with a reaction product of an alkali metal hydroxide and polyglycol and a reagent composed of oxygen has been proposed (US Pat. No. 4,400,352). ). However, this method is disadvantageous in that it requires an excessive amount of reagent relative to the object to be processed and the reactivity of the reagent is poor.

  Furthermore, a method for reductively dehalogenating a treatment object by heating it in the presence of an alkali and a catalyst has been proposed (Japanese Patent No. 3025701). However, this method also has a problem that the reactivity of the reagent is poor and a long processing time is required.

  Furthermore, there has been proposed a method in which hydrocarbons, IPA and metallic sodium are added to the pesticides to be treated to perform a dechlorination reaction (Proceedings of the 14th Annual Meeting of the Waste Society, 2003, 1295). Pages to 1297). However, this method has a problem that a toxic substance such as benzene is generated as a reaction product in addition to the time required for separating the agricultural chemical from the matrix.

  In addition, a method has been proposed in which the processing object is finely dispersed and powdered to change its properties and enhance chemical reactivity. For example, in the case of treating an organic chlorine compound, a method has been proposed in which after the DCR treatment is performed, an alkali and a catalyst are added to the produced dry powder and kneaded for decomposition. However, this method has problems that the chemicals to be used are expensive and that a large-scale waste gas treatment facility for removing moisture by reaction / evaporation is necessary.

  The present invention solves the above-mentioned problems of the prior art, and in a method of treating residual organic pollutants such as waste pesticides by an indirect heat treatment method, improves the decomposition efficiency of the pollutants and reduces the burden of exhaust gas treatment. It is an object to provide a method for performing a safe and reliable process at a low cost, which can greatly reduce the above-mentioned.

  As means for solving the above-mentioned problems, the present inventors mixed organic pollutants, solid media, alkaline agents, and high-boiling polar solvents, and heated the mixture to make residual organic. A method for treating pollutants was invented and a patent application was filed (Japanese Patent Application No. 2004-166248).

  In this method, a large excess amount of a heating medium (for example, sand particles) of 10 to 1000 times is present with respect to the organic pollutant to be treated, and an alkali agent and a high-boiling polar solvent are added and heated (indirectly). By heating, the organic pollutant is reacted with an alkaline agent to be decomposed.

  As a result of further investigations related to this technique, the present inventors have found that, particularly when the amount of the solid medium (heating medium) is about 5 times or less of the organic pollutant to be treated, It has been found that the reaction system temperature is raised by the reaction heat itself due to the reaction between the pollutant and the alkaline agent, and that the decomposition reaction of the organic pollutant proceeds rapidly without substantially applying heat from the outside. It came to be completed. That is, one embodiment of the present invention is a method for treating persistent organic pollutants, which is characterized by mixing an organic pollutant, a solid medium, an alkaline agent, and a high-boiling polar solvent. Regarding the method.

  Organic pollutants that can be treated according to the present invention include persistent waste pesticides, particularly organochlorine or drin-based waste pesticides. Examples of organochlorine pesticides that can be treated according to the present invention include BHC, hexachlorobenzene, DDT, chlordane, heptachlor, toxaphene, and the like. Can be mentioned. Furthermore, the method of the present invention can treat organophosphorus pesticides such as pyracrophos and propaphos, and carbamate pesticides such as carbaryl and ashram. Furthermore, according to the present invention, it is possible to treat various insecticides, herbicides, insecticides, fungicides, fungicides, and the like, and further residual organic halides such as chlorinated dioxins and PCBs. Organic pollutants can also be treated according to the present invention. In addition, according to the present invention, it is possible to purify contaminated soil, contaminated sediment, sludge, sediment, waste, incinerated ash, etc. contaminated by the various organic compounds as organic pollutants to be treated. .

  In the method of the present invention, an organic contaminant to be treated is added to and mixed with a solid medium. The solid medium acts as a heating medium when thermally decomposing organic pollutants. The solid medium used for this purpose is preferably in the form of powder or granule, and also has a certain level of organic pollutant retention ability, heat resistance that can withstand heat treatment, wear resistance, alkali resistance, and ease. Specific gravity that does not scatter is required. Specific examples of the granular or powdered solid medium that can be used in the present invention include natural minerals such as sand, gravel and gravel, artificial minerals such as ceramics and beads, or metallic powders such as iron. Powder, Mn powder, Zn powder (granule), etc. can be used. The size of the granular or powdered solid medium is preferably 0.1 mm or more in order to suppress dust.

  In the present invention, the solid medium further includes at least one of alkali metal carbonate, bicarbonate or hydroxide, or at least one of alkaline earth metal oxide or hydroxide (hereinafter referred to as “alkaline agent”). ) And a high-boiling polar solvent are added and mixed to treat organic contaminants. Alkali agents that can be used include alkali metals or alkaline earth metals, such as metal sodium, metal potassium; alkali metal or alkaline earth metal hydroxides, such as sodium hydroxide, potassium hydroxide, calcium hydroxide. Magnesium hydroxide; alkali metal carbonates or bicarbonates such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate; alkaline earth metal oxides such as calcium oxide, magnesium oxide, etc. be able to. These alkaline agents can be supplied as a solid or liquid (aqueous solution). The high-boiling polar solvent means a solvent having a boiling point of 150 ° C. or higher, preferably 190 ° C. or higher. Specifically, glycols such as ethylene glycol, polyethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol. Alternatively, glycol alkyl ethers such as ethylene glycol / diethyl ether, diethylene glycol / diethyl ether, tetraethylene glycol / dimethyl ether, dipropylene glycol / monopropyl ether, and the like can be used. In the method of the present invention, by adding a high-boiling polar solvent such as glycol to the alkali agent, the alkali is efficiently dissociated, and the reactivity with the object to be treated at room temperature or in the vicinity thereof is dramatically improved. .

  In the method of the present invention, the organic pollutant is mixed with the solid medium, the alkali agent and the high boiling polar solvent described above. The mixing rate of organic pollutants varies depending on the difficulty of decomposition of the pollutants to be treated, the amount of heat generated by the reaction between the pollutants to be treated and the alkaline agent, the heat capacity of the objects to be treated, the heat capacity of the solid medium, etc. In general, the organic contaminant is preferably 3 to 50% by weight, more preferably 3 to 35% by weight or less, and still more preferably 3.3 to 30% by weight based on the solid medium. In addition, this value is a state in which the organic pollutant to be treated is diluted as in the case where the organic pollutant is in the form of a preparation or the contaminated medium contaminated with persistent organic pollutant is treated. In this case, it means the weight ratio of the component to be decomposed (organic compound to be decomposed). If the amount of solid medium originally present is sufficiently large, it may not be necessary to add new solid medium. As will be described later, when organic contaminants are gradually added to and mixed with a solid medium to which an alkaline agent and a high-boiling polar solvent are added, the amount of organic contaminants with respect to the solid medium is determined by the reaction system. Means the amount of organic pollutant present. That is, when an organic contaminant is added to and mixed with a solid medium to which an alkaline agent and a high boiling polar solvent are added, the organic contaminant is decomposed by reaction with the alkaline agent. When organic pollutants are further added thereto, the amount of the organic pollutants in the above quantitative ratio means an amount excluding the decomposed portion.

  In addition, since the alkali agent has a function of capturing a reaction substrate of an organic pollutant and preventing the generation of a new harmful substance, for this purpose, the mixing ratio of the alkali agent is the reaction substrate. For example, when the object to be treated is an organic halogen compound, it is sufficient that it is 1 mol or more with respect to 1 mol of halogen in the object to be treated, and more preferably 1.5 to 3.0 mol. Further, since the high boiling polar solvent has a function of providing a reaction field by dissolving the organic pollutant and the alkaline agent, for this purpose, the mixing ratio of the high boiling polar solvent is a solid medium. The content is preferably 1 to 30% by weight, more preferably 1 to 20% by weight. In order to form a uniform mixture, it may be preferable to add and mix the alkaline agent and the high boiling polar solvent after dissolving in water. Further, the mixing order of the solid medium, the alkaline agent, the high boiling polar solvent, and the organic contaminant is not particularly limited. For example, the organic pollutant to be treated is first added to and mixed with the solid medium, and then the alkali agent and the high-boiling polar solvent may be added to the mixture, or the alkali agent and the high-boiling polar solvent are added to the solid medium. What mixed may be used as a processing chemical | medical agent, and the organic pollutant to be processed may be added and mixed here. In addition, when mixing each component, it may be preferable to add and knead some water.

  In the method of the present invention, by mixing the solid medium, the alkaline agent, the high-boiling polar solvent and the organic pollutant, the temperature of the reaction system rises due to the reaction heat itself generated by the reaction between the organic pollutant and the alkaline agent. As the temperature rises, the reaction between the organic pollutant and the alkaline agent is further promoted, and the organic pollutant can be decomposed by almost 100% without substantially applying heat from the outside. . In the method of the present invention, the alkali is efficiently dissociated by adding a high-boiling polar solvent such as glycols or glycol alkyl ethers to the alkali agent, and the treatment object at room temperature and in the vicinity thereof The responsiveness of the drastically improved.

  The order of mixing the solid medium, the alkaline agent, the high boiling polar solvent and the organic contaminant is not particularly limited. However, in order to control the amount of heat generated by the reaction heat and maintain it within a predetermined temperature range, which will be described later, first, a high-boiling polar solvent is uniformly dispersed in the solid medium, and then an alkali agent is added to make it uniform Thoroughly knead to form a mixed medium. A method of adding and kneading the organic pollutant to be treated to the mixed medium while controlling the addition amount little by little so that the temperature does not increase excessively is most preferable. In addition, the mixing order of a solid medium, an alkali agent, and a high boiling point polar solvent is not limited to said method, A mixing order can be changed. However, it is preferable to add and mix organic contaminants last. The reason for this is that the reaction amount of organic pollutants is directly linked to the temperature rise, so if an alkali agent is added to the system where organic pollutants are mixed, the reaction proceeds explosively and a large amount of For example, it may be difficult to control the reaction such as generation of gas or risk of ignition. In addition, when an alkaline agent and glycols or glycol alkyl ethers (high boiling polar solvents) are directly added to agricultural chemicals, the composition and shape are often changed by an exothermic reaction. Organic contaminants and alkalis may adhere to the solid medium via diethylene glycol. Particularly in such a case, in order to easily knead the mixture and quickly increase the temperature, it is preferable to add a slight amount of water to the mixture and knead.

  Further, an alkali agent and glycols or glycol alkyl ethers (high-boiling polar solvents) can be added to an organic pollutant to be treated dispersed in a solid medium. In general, agricultural chemical preparations are designed to be easy to handle and improve the sustainability of the effect by adding bentonite or the like to the active ingredient to dilute and disperse. When the drug substance concentration in the agrochemical formulation is 10% or more, in order to increase the heat capacity of the reaction system, add a solid medium such as sand to the preparation and dilute the drug substance to a drug substance concentration of less than 10%. Therefore, it is possible to suppress an increase in temperature due to the addition of an alkali agent and glycols or glycol alkyl ethers (high boiling polar solvent). In this method, an alkaline agent is slowly added to an organic pollutant, a solid medium, a high-boiling polar solvent, and optionally water kneaded while monitoring the temperature, so that the temperature of the reaction system is 30 to 80 ° C. It is preferable to perform mixing while controlling the amount of the alkali agent added so as to be maintained.

  In addition, when the organic pollutant to be treated is an agrochemical formulation, the agrochemical component is often diluted with bentonite or the like, and in this case, a very small amount of solid medium may be added to the system or not at all. It may not be necessary.

  In the method of the present invention, as described above, the reaction system is generated by the reaction heat itself generated by the reaction between the alkali agent and the organic pollutant by mixing the high boiling polar solvent, the alkali agent, the high boiling polar solvent and the organic pollutant. Temperature rises. Therefore, these components can be kneaded at room temperature, and the reaction can be efficiently advanced by a natural temperature rise due to heat generation. However, when the temperature of the reaction system exceeds, for example, 100 ° C., problems such as evaporation of water and generation of a large amount of gas occur. Therefore, as described above, the organic pollutant is gradually added to the mixed medium in which the high-boiling polar solvent, the alkaline agent, and the high-boiling polar solvent are mixed while controlling the addition amount so that the temperature of the reaction system does not rise too much. In addition, it is preferable to knead. In practice, the mixing amount of organic pollutants is controlled so that the temperature of the reaction system is maintained within the range of 30 to 100 ° C, preferably 30 to 90 ° C, more preferably 40 to 80 ° C. Is preferred. In addition, a cooler may be installed in the reaction apparatus (mixing apparatus) to cool the reaction mixture as necessary. Furthermore, when the temperature rise of the reaction system due to the reaction heat between the organic pollutant and the alkaline agent is small, the temperature of the reaction system may be maintained within an appropriate range by heating from the outside.

  In the treatment of the mixture, it is preferable to create an inert atmosphere by means such as supplying nitrogen in order to prevent generation of harmful by-products. The mixing time varies depending on the nature and amount of the organic contaminant to be treated, the temperature of the reaction system, etc., but is generally 5 minutes to 120 minutes, preferably 15 to 100 minutes, more preferably 30 to 60 minutes. preferable.

  After the organic pollutant is decomposed, the solid medium can be taken out, allowed to cool to room temperature if necessary, and then treated again by adding the organic pollutant.

  According to the method of the present invention, the temperature of the reaction system rises due to the reaction heat itself generated by the reaction between the organic pollutant to be treated and the alkaline agent, thereby promoting the decomposition reaction of the organic pollutant, and substantially externally. Over 97% of organic pollutants can be decomposed without applying more heat. However, for example, when decomposing substances listed in the POPs Convention, the permissible concentration in the environment is small, and when performing detoxification treatment, the decomposition efficiency is 6 nines (99.9999%) or more. Required. Thus, when it is necessary to further completely decompose organic pollutants, the organic pollutants can be decomposed more completely by heating the reaction mixture treated by the method of the present invention in a heating reactor. can do.

  In the case of performing such a decomposition treatment, for example, in the method disclosed in Japanese Patent Application No. 2004-166248 filed by the present applicant, for example, 800 parts by weight of an alkaline agent and high boiling point with respect to 1,000 parts by weight of BHC. 200 parts of a polar solvent is added, and further 98,000 parts by weight of a solid medium (sand) is added to make a total of 100,000 parts by weight, and the mixture is processed in a heating reactor. On the other hand, in the method of the present invention, for example, 800 parts by weight of alkaline agent and 200 parts of high boiling polar solvent are added to 1,000 parts by weight of BHC, and 3,000 parts by weight of a solid medium (sand) is added to the whole. After the mixture of 5,000 parts by weight is kneaded to decompose the BHC, the BHC is completely decomposed by putting it in a heating reactor and processing it. Therefore, according to the method of the present invention, since the amount of BHC to be decomposed in the heating reactor is overwhelmingly small, the load on the heating reactor is greatly reduced, and the overall cost can be reduced. Furthermore, the former method can process a mixture having a capacity of 100,000 parts by weight of the heating reactor, whereas the method of the present invention can process a mixture of 5,000 parts by weight in the heating reactor. It is enough. Therefore, according to the method of the present invention, the size of the heating reactor can be reduced to 1/20, and both the apparatus cost and the operating cost can be significantly reduced.

  In addition, the present invention controls the amount of organic pollutant added to the mixed medium in which the high-boiling polar solvent, alkali agent, and high-boiling polar solvent described above are mixed so that the temperature of the reaction system does not rise excessively. The present invention also relates to an apparatus for decomposing organic pollutants by adding them little by little and kneading them. That is, another aspect of the present invention includes a mixing reactor having a stirring device; a storage tank for storing a solid medium, a high-boiling polar solvent, an alkaline agent, and an organic contaminant to be treated; Metering feeder for metering medium, high-boiling polar solvent, alkaline agent to mixing reactor; Metering feeder for metering organic contaminants to be treated from storage tank to mixing reactor; Temperature of the mixture in the mixing reactor An organic pollutant supply amount control means for controlling a supply amount of a quantitative supply device for metering organic pollutants from the storage tank to the mixing reactor according to a temperature measured by the temperature measuring device; The present invention relates to an organic pollutant treatment apparatus. Still another embodiment of the present invention includes a mixing reactor having a stirring device; a solid medium, a high boiling point polar solvent, an alkaline agent, and a storage tank for storing organic contaminants to be treated; a solid medium, a high boiling point polarity. Mixer for pre-mixing solvent and alkali agent; solid supply medium, high boiling point polar solvent, metering feeder for metering alkali agent from each storage tank; solid medium mixed in mixer, high boiling point polar solvent And means for supplying a mixture of alkaline agents to the mixing reactor; a metering supply for metering organic contaminants to be treated from the storage tank to the mixing reactor; a temperature measuring device for measuring the temperature of the mixture in the mixing reactor; Organic pollutant supply amount control means for controlling the supply amount of a quantitative supply device for metering and supplying organic pollutants from the storage tank to the mixing reactor according to the temperature measured by the temperature measuring device. That relates to the treatment apparatus of organic pollutants.

  The concept of such an apparatus will be described with reference to the drawings. FIG. 1 relates to an organic contaminant processing apparatus according to one embodiment of the present invention. Sand storage tanks as solid media, DEG (diethylene glycol) storage tanks as high-boiling polar solvents, and alkaline agent storage tanks are connected to the mixing reactor via quantitative feeders. , DEG and an alkaline agent are supplied to the mixing reactor and mixed and stirred in advance by a stirring device to form a mixed medium. Here, the processing object in a storage tank is similarly supplied to a mixing reactor via a fixed quantity feeder. At this time, the temperature of the mixture is measured by a temperature measuring device installed in the reactor, and the supply amount of the processing object is controlled by the controller so that the temperature does not exceed a predetermined preferable range, for example, 80 ° C. If desired, a cooler can be attached to the mixing reactor. The treated product can be appropriately discharged from the mixing reactor. Further, the treatment can be continuously performed by continuously supplying each component and allowing the mixture to stay in the mixing reactor for a predetermined time and then discharging the mixture. Exhaust gas is discharged from the reactor, and a small amount of untreated organic pollutant remains in the exhaust gas. Accordingly, the exhaust gas is cooled as necessary, and then passed through a catalyst tank and an activated carbon tank (not shown), whereby residual organic pollutants in the exhaust gas can be further removed and discharged into the atmosphere. According to the present invention, it is possible to efficiently decompose and remove residual organic pollutants in the object to be processed in the mixing reactor, so that the burden on the catalyst tank and the activated carbon tank can be reduced. Examples of the organic pollutant decomposition catalyst that can be used in such a residual organic pollutant treatment system include noble metal catalysts, platinum oxide, vanadium oxide, and the like.

  In addition, as shown in FIG. 2, the apparatus can be configured such that sand, DEG, and an alkali agent are mixed and stirred in advance by a mixer to form a mixed medium and supplied to the mixing reactor.

  In addition, when processing organic pollutants with small reaction heat as an object to be processed according to the present invention, the raw material can be mixed with an alkali agent and a high-boiling polar solvent without adding a solid medium. There is a case. Such forms are also included within the scope of the present invention.

  Various aspects of the present invention are as follows.

  1. A method for treating residual organic pollutants, the method comprising mixing organic pollutants, an alkaline agent, and a high-boiling polar solvent.

  2. A method for treating persistent organic pollutants, comprising mixing organic pollutants, a solid medium, an alkaline agent, and a high boiling polar solvent.

  3. A method for treating residual organic pollutants contained in a solid medium, comprising mixing organic pollutants in a solid medium, an alkali agent, and a polar solvent having a high boiling point.

  4). The method according to any one of the above items 1 to 3, wherein the mixture is maintained under an inert atmosphere.

  5. Item 5. The method according to any one of Items 1 to 4, wherein the organic pollutant is a solid or liquid pesticide.

  6). 6. The method according to any one of items 1 to 5, wherein the organic pollutant is mixed with the solid medium in an amount of 3 to 50% by weight or less as the weight of the pollutant component to be treated.

  7. The method according to any one of Items 1 to 6, wherein the solid medium is a natural mineral, an artificial mineral, or a metallic powder.

  8). Any one of the above items 1 to 7, wherein the alkaline agent is at least one of an alkali metal or alkaline earth metal hydroxide, an alkali metal carbonate or bicarbonate, or an alkaline earth metal oxide. The method described in 1.

  9. 9. The method according to any one of items 1 to 8, wherein the high-boiling polar solvent is a glycol or a glycol alkyl ether.

  10. High boiling polar solvent is ethylene glycol, polyethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, tetraethylene glycol dimethyl ether or dipropylene glycol monopropyl 10. A process according to item 9 which is an ether.

  11. An alkaline agent and a high-boiling polar solvent are added and mixed in a solid medium to form a mixed medium, and the amount of organic contaminants is controlled while maintaining the reaction system temperature at a predetermined value or less. The method according to any one of Items 2 to 10, which is added to and mixed with a mixed medium.

  12 12. The method according to the above item 11, wherein the temperature of the reaction system is maintained at 100 ° C. or lower.

  13. A mixing reactor equipped with a stirring device; a storage tank for storing a solid medium, a high-boiling polar solvent, an alkaline agent, and an organic contaminant to be treated; a solid medium, a high-boiling polar solvent, and an alkaline agent from each storage tank A metering feeder for metering to the mixing reactor; a metering meter for metering the organic pollutant to be treated from the storage tank to the mixing reactor; a temperature measuring device for measuring the temperature of the mixture in the mixing reactor; a temperature measuring device An organic pollutant supply control means for controlling a supply amount of a quantitative feeder for metering organic pollutants from the storage tank to the mixing reactor according to the temperature measured by Processing equipment.

  14 A mixing reactor having a stirring device; a storage tank for storing a solid medium, a high-boiling polar solvent, an alkaline agent, and an organic pollutant to be treated; a mixer for previously mixing a solid medium, a high-boiling polar solvent, and an alkaline agent A metering feeder for metering a solid medium, a high-boiling polar solvent, and an alkaline agent from each storage tank to the mixer; a mixture of the solid medium, the high-boiling polar solvent, and the alkaline agent mixed in the mixer into a mixing reactor Means for feeding; metering feeder for metering the organic pollutant to be treated from the storage tank to the mixing reactor; temperature measuring device for measuring the temperature of the mixture in the mixing reactor; depending on the temperature measured by the temperature measuring device, Organic pollutant supply control means for controlling the supply amount of a quantitative feeder for metering and supplying organic pollutants from the storage tank to the mixing reactor; Location.

  15 Mixing reactor equipped with a stirring device; Reservoir for storing high-boiling polar solvent, alkaline agent, and organic pollutant to be treated; Metering supply of high-boiling polar solvent and alkaline agent from each reservoir to the mixing reactor A quantitative feeder for metering the organic pollutant to be treated from the storage tank to the mixing reactor; a temperature measuring device for measuring the temperature of the mixture in the mixing reactor; depending on the temperature measured by the temperature measuring device An organic pollutant supply amount control means for controlling a supply amount of a quantitative feeder for metering and supplying organic pollutants from the storage tank to the mixing reactor.

  16. A mixing reactor equipped with a stirrer; a storage tank for storing a high-boiling polar solvent, an alkaline agent, and an organic contaminant to be treated; a mixer for pre-mixing a high-boiling polar solvent and an alkaline agent; High-polarity polar solvent and metering agent for metering alkali agent into the mixer; Means for feeding the mixture of high-boiling polar solvent and alkali agent mixed in the mixer to the mixing reactor; Organic contamination to be treated from the storage tank Metering feeder for metering substances into the mixing reactor; Temperature measuring device for measuring the temperature of the mixture in the mixing reactor; Measuring organic pollutants from the reservoir to the mixing reactor by the temperature measured by the temperature measuring device An organic pollutant treatment apparatus characterized by comprising: an organic pollutant supply amount control means for controlling the supply amount of a quantitative feeder to be supplied.

  17. Item 17. The apparatus according to any one of Items 13 to 16, wherein a condenser is attached to the mixing reactor.

  The following examples illustrate the invention, but the invention is not limited by the following description.

Example 1
While mixing 0.5 kg of PCNB (pentachloronitrobenzene) and 1.2 kg of NaOH in a mixer (product name: PM-33S, manufactured by Maseller Co., Ltd.), then adding 1 kg of DEG (diethylene glycol) little by little, heat of reaction The mixture was kept at a temperature of 50 to 65 ° C. and kneaded sufficiently for about 2 hours.

  After allowing to cool, the mixture and the mixer were washed with a solvent (ethyl acetate) and analyzed for PCNB in the washing solution. The decomposition rate was 90%.

Example 2
In a mixer similar to that in Example 1, 1.2 kg of PCNB (pentachloronitrobenzene) powder and 0.3 kg of NaOH were added and mixed, and then 0.5 kg of DEG (diethylene glycol) was added. While fully kneading this mixture, 23 kg of air-dried sand having an effective diameter of 0.45 mm and a uniformity coefficient of 1.3 was gradually added and mixed. The temperature of the mixture increased due to the heat of reaction. The mixture was kept at a temperature of 60 to 90 ° C. for 1 hour, and then allowed to cool. The sand and the mixer were washed with a solvent (ethyl acetate), and PCNB in the washing solution was analyzed. It was. Therefore, the removal rate of PCNB was 99% or more.

Example 3
In a mixer similar to that in Example 1, 5 kg of PCNB (pentachloronitrobenzene) powder was added, and then a sufficiently mixed mixture of 2 kg of KOH and 1.2 kg of polyethylene glycol was added and kneaded. Next, 15 kg of sand as in Example 2 was gradually added and mixed. The temperature of the mixture increased due to the heat of reaction. After maintaining the temperature of the mixture at 75 to 95 ° C. for 1 hour, the mixture was allowed to cool, the sand and the mixer were washed with a solvent (ethyl acetate), and PCNB in the washing solution was analyzed. became. Therefore, the removal rate of PCNB was 99% or more.

Example 4
In a mixer similar to that in Example 1, 1.5 kg of BHC (benzene hexachloride) powder and 24 kg of sand as in Example 2 were added, and 1.8 kg of polyethylene glycol was added and sufficiently kneaded. Next, 1.6 kg of potassium hydroxide was gradually added. The temperature of the mixture increased due to the heat of reaction. The mixture was kept at a temperature of 60 to 80 ° C. for 2 hours, then allowed to cool, the sand and the mixer were washed with a solvent (ethyl acetate), and BHC in the washing solution was analyzed. The BHC removal rate was 99.3%. Met.

Example 5
In the same mixer as in Example 1, 90 kg of sand as in Example 2 was added, 4 kg of diethylene glycol was added, and then 8 kg of sodium hydroxide was added, and kneaded sufficiently to be uniform. 10 kg of BHC powder was slowly added and mixed so that the temperature of the mixture rising by reaction heat did not exceed 90 ° C., and the temperature of the mixture was maintained at 75 ° C. or higher for 0.5 hour. Thereafter, the mixture was allowed to cool, the sand and the mixer were washed with a solvent (ethyl acetate), and BHC in the washing solution was analyzed. The removal rate of BHC was 98.4%.

Example 6
In the same mixer as in Example 1, 0.5 kg of PCNB (pentachloronitrobenzene) and 1.2 kg of NaOH were added and mixed, and then 1 kg of dipropylene glycol monopropyl ether was added little by little, and the temperature of the mixture due to the heat of reaction. Was kept at 50 to 65 ° C. and sufficiently kneaded for 2 hours. After allowing to cool, the mixture and the mixer were washed with a solvent (ethyl acetate) and analyzed for PCNB in the washing solution. The decomposition rate was 93%.

Example 7
In the same mixer as in Example 1, 1.2 kg of PCNB (pentachloronitrobenzene) powder and 0.3 kg of NaOH were added and mixed, and then 0.5 kg of dipropylene glycol monopropyl ether was added. While fully kneading this mixture, 23 kg of air-dried sand having an effective diameter of 0.45 mm and a uniformity coefficient of 1.3 was gradually added and mixed. The temperature of the mixture increased due to the heat of reaction. The mixture was kept at a temperature of 75 to 95 ° C. for 1 hour, and then allowed to cool. The sand and the mixer were washed with a solvent (ethyl acetate) and analyzed for PCNB in the washing solution. It was. Therefore, the removal rate of PCNB was 99% or more.

Example 8
In a mixer similar to that in Example 1, 1.5 kg of BHC (benzene hexachloride) powder and 24 kg of sand as in Example 2 were added, and 1.8 kg of ethylene glycol diethyl ether was added and kneaded sufficiently. Next, 1.6 kg of potassium hydroxide was gradually added. The temperature of the mixture increased due to the heat of reaction. The mixture was kept at a temperature of 60 to 80 ° C. for 2 hours and then allowed to cool. The sand and the mixer were washed with a solvent (ethyl acetate), and BHC in the washing solution was analyzed. The BHC removal rate was 98.3%. Met.

Example 9
In the same mixer as in Example 1, 90 kg of sand similar to that in Example 2 was added, 4 kg of diethylene glycol / diethyl ether was added, and then 8 kg of sodium hydroxide was added, and kneaded sufficiently to be uniform. 10 kg of BHC powder was slowly added and mixed so that the temperature of the mixture rising by reaction heat did not exceed 90 ° C., and the temperature of the mixture was maintained at 75 ° C. or higher for 0.5 hour. Thereafter, the mixture was allowed to cool, the sand and the mixer were washed with a solvent (ethyl acetate), and BHC in the washing solution was analyzed. The removal rate of BHC was 99.6%.

Example 10
In the same mixer as in Example 1, 90 kg of sand and 8 kg of sodium hydroxide as in Example 2 were added, and kneaded sufficiently so as to be uniform. Next, 4 kg of tetraethylene glycol and dimethyl ether are added, and 10 kg of BHC powder is slowly added and mixed so that the temperature of the mixture rising by reaction heat does not exceed 90 ° C., and the temperature of the mixture is adjusted to 75 to 85 ° C. Hold for 0.5 hour. Thereafter, the mixture was allowed to cool, the sand and the mixer were washed with a solvent (ethyl acetate), and BHC in the washing solution was analyzed. As a result, the BHC removal rate was 99%.

  According to the present invention, residual organic pollutants such as waste agricultural chemicals can be decomposed at a high decomposition rate in a solid medium. In addition, since the amount of residual organic pollutants in the exhaust gas generated during the treatment is greatly reduced, the exhaust gas treatment load is reduced when the exhaust gas treatment is performed. Further, harmless substances generated by the treatment according to the present invention can be recovered and reused as resources. According to the method of the present invention, most harmful substances can be decomposed into harmless substances by a simple mixing process without external heating, and trace amounts of harmful substances can be obtained by further heat treatment if necessary. Since the substance is completely decomposed, it can be reliably processed. In addition, when the latter heat treatment is performed, the amount of solid medium used is small compared to the ordinary indirect heating method, so the heating device can be reduced in size, and both the device cost and the operating cost can be reduced. It is.

It is a figure which shows the structural example of the apparatus which decomposes | disassembles the organic pollutant concerning 1 aspect of this invention. It is a figure which shows the other structural example of the decomposition | disassembly apparatus of the organic pollutant concerning 1 aspect of this invention.

Claims (17)

A method for treating residual organic pollutants, the method comprising mixing organic pollutants, an alkaline agent, and a high-boiling polar solvent. A method for treating persistent organic pollutants, comprising mixing organic pollutants, a solid medium, an alkaline agent, and a high boiling polar solvent. A method for treating residual organic pollutants contained in a solid medium, comprising mixing organic pollutants in a solid medium, an alkaline agent, and a polar solvent having a high boiling point. The method according to any one of claims 1 to 3, wherein the mixture is maintained under an inert atmosphere. The method according to any one of claims 1 to 4, wherein the organic pollutant is a solid or liquid pesticide. The method according to claim 1, wherein the organic pollutant is mixed with the solid medium in an amount of 3 to 50% by weight or less as the weight of the pollutant component to be treated. The method according to claim 1, wherein the solid medium is a natural mineral, an artificial mineral, or a metallic powder. The alkaline agent is at least one of an alkali metal or alkaline earth metal hydroxide, an alkali metal carbonate or bicarbonate, or an alkaline earth metal oxide. Method. The method according to any one of claims 1 to 8, wherein the high-boiling polar solvent is a glycol or a glycol alkyl ether. High boiling polar solvent is ethylene glycol, polyethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, tetraethylene glycol dimethyl ether or dipropylene glycol monopropyl ether The method according to claim 9. An alkaline agent and a high-boiling polar solvent are added and mixed in a solid medium to form a mixed medium, and the amount of organic contaminants is controlled while maintaining the reaction system temperature at a predetermined value or less. The method according to any one of claims 2 to 10, which is added to and mixed with a mixed medium. The method according to claim 11, wherein the temperature of the reaction system is maintained at 100 ° C. or lower. A mixing reactor equipped with a stirring device; a storage tank for storing a solid medium, a high-boiling polar solvent, an alkaline agent, and an organic contaminant to be treated; a solid medium, a high-boiling polar solvent, and an alkaline agent from each storage tank A metering feeder for metering to the mixing reactor; a metering meter for metering the organic pollutant to be treated from the storage tank to the mixing reactor; a temperature measuring device for measuring the temperature of the mixture in the mixing reactor; a temperature measuring device An organic pollutant supply control means for controlling a supply amount of a quantitative feeder for metering organic pollutants from the storage tank to the mixing reactor according to the temperature measured by Processing equipment. A mixing reactor having a stirring device; a storage tank for storing a solid medium, a high-boiling polar solvent, an alkaline agent, and an organic pollutant to be treated; a mixer for previously mixing a solid medium, a high-boiling polar solvent, and an alkaline agent A metering feeder for metering a solid medium, a high-boiling polar solvent, and an alkaline agent from each storage tank to the mixer; a mixture of the solid medium, the high-boiling polar solvent, and the alkaline agent mixed in the mixer into a mixing reactor Means for feeding; metering feeder for metering the organic pollutant to be treated from the storage tank to the mixing reactor; temperature measuring device for measuring the temperature of the mixture in the mixing reactor; depending on the temperature measured by the temperature measuring device, Organic pollutant supply control means for controlling the supply amount of a quantitative feeder for metering and supplying organic pollutants from the storage tank to the mixing reactor; Location. Mixing reactor equipped with a stirrer; Reservoir for storing high-boiling polar solvent, alkaline agent, and organic pollutant to be treated; Metering supply of high-boiling polar solvent and alkaline agent from each reservoir to the mixing reactor A quantitative feeder for metering the organic pollutant to be treated from the storage tank to the mixing reactor; a temperature measuring device for measuring the temperature of the mixture in the mixing reactor; depending on the temperature measured by the temperature measuring device An organic pollutant supply amount control means for controlling a supply amount of a quantitative feeder for metering and supplying organic pollutants from the storage tank to the mixing reactor. A mixing reactor equipped with a stirrer; a storage tank for storing a high-boiling polar solvent, an alkaline agent, and an organic contaminant to be treated; a mixer for pre-mixing a high-boiling polar solvent and an alkaline agent; High-polarity polar solvent and metering agent for metering alkali agent into the mixer; Means for feeding the mixture of high-boiling polar solvent and alkali agent mixed in the mixer to the mixing reactor; Organic contamination to be treated from the storage tank Metering feeder for metering substances into the mixing reactor; Temperature measuring device for measuring the temperature of the mixture in the mixing reactor; Measuring organic pollutants from the reservoir to the mixing reactor by the temperature measured by the temperature measuring device An organic pollutant treatment apparatus characterized by comprising: an organic pollutant supply amount control means for controlling the supply amount of a quantitative feeder to be supplied. The apparatus according to claims 13 to 16, wherein a condenser is attached to the mixing reactor.

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