JP2015071144A - Original-position pollution countermeasure system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct pollution countermeasure system which is significantly different from conventional pollution countermeasures characterized by simple purification of polluted soil and underground water, and has a new concept that pollution purification is attempted based on regeneration of resource values including polluted underground water or the like, and reduction of environmental loads.SOLUTION: An original-position pollution countermeasure system has a water creation mechanism which comprises: forming a heat region at a soil and ground water polluted site; promoting growth of thermophilic bacteria so as to reduce pollution of soil and underground water by specified bacteria and/or chemicals while keeping the environmental load at a low level; storing pumped underground water in a storage hot-water unit so as to further reduce specified bacteria in the pumped water; and promoting reuse of the pumped water as general service water.

Description

  The present invention relates to a pollution control system whose main purpose is to provide a purification measure for groundwater whose resource value has been lost due to soil groundwater contamination, and a recycling method as miscellaneous water for purification.

  Since the 1990s, social interest in soil and groundwater contamination has increased, and various technical proposals have been made from practical use of contamination investigations to purification measures (see, for example, Patent Documents 1 to 11). Generally, if contamination is detected in groundwater, drinking and use restrictions are imposed on groundwater first, then a detailed contamination survey is conducted, and further purification is performed. There are very few cases that are canceled. In other words, the completion of the pollution cleanup currently implemented means that the cleanliness of the legally polluted chemical substances has generally been achieved to meet the standard level, and that there is no problem in drinking and using the groundwater. It was not a thing.

  In this way, the conventional pollution purification technology has not necessarily been carried out until the value of water resources is restored to the contaminated groundwater. In addition, depending on the purification technology, a large amount of purification material is put into the ground to purify pollution against legally polluted chemical substances, which imposes an additional environmental burden on the groundwater, which makes it more difficult to drink and use groundwater. There were also technologies that would be a concern if we gave up on the situation.

JP-T-2002-513676 JP 2008-194590 A JP 2006-150278 A JP 09-276841 A Japanese Patent Application Laid-Open No. 07-308660 Japanese Patent Laid-Open No. 08-112586 JP 2007-296527 A JP 2002-11456 A JP 2007-253057 A JP 2004-305898 A Japanese Patent Application Laid-Open No. 07-265845

  These various cleanup countermeasure technologies have excellent pollution cleanup effects depending on the types of legal pollutants and environmental conditions, but on the other hand, they are not legislated and are almost omitted in many pollution cleanup measures. There were the following problems with respect to the environmental aspects and the effect on the groundwater resource value in the cleanup construction.

  First, the in-situ purification method using an oxidizing agent such as permanganate disclosed in Patent Document 1 uses groundwater as a water resource in that it uses manganese that exists as a regulated substance in water quality standards and the like. There was a problem that detracted from the resource value.

In addition, in the purification countermeasure method using other oxidizing agents shown in Patent Document 2, most of the aquifer maintained in the reduced state and its vicinity are completely oxidized by injecting the oxidizing agent. In some cases, dissolved metal salts present in reductive groundwater and infused chemicals are oxidized to form insoluble precipitates, which promote clogging of the aquifer by these precipitates, There were concerns about changes in the direction of groundwater flow.
The impact on the groundwater flow direction due to the clogging of the aquifer gap has the problem of inducing artificial secondary pollution damage such as inadvertently causing new contamination by causing the remaining contamination to flow in a direction that does not occur. It was.

  In addition, the biological purification method using the anaerobic dechlorination method shown in Patent Document 3 injects and rotifies water-soluble organic matter into the basement, promotes the growth of anaerobic microorganisms, forms a reducing environment, This is a technique for promoting the action of some bacteria that exhibit a dechlorination action on pollutants in the reducing environment to detoxify organochlorine pollutants.

Since this technique has a process operation that promotes the growth of miscellaneous spoilage bacteria at medium temperature, there remains a problem that pathogenic bacteria may proliferate and increase with respect to humans who prefer a medium temperature range. In addition, as a by-product of the metabolism of anaerobic microorganisms, it is accompanied by the generation of various organic acids, volatile fatty acids that are regulated and recognized as malodorous substances, and the generation of harmful substances such as hydrogen sulfide and methane. It was.
Overall, this technology requires careful attention to the effects of odors / hazardous gases generated in the purification area on the living environment and the natural world, as well as sacrificing the value of groundwater as a water resource from a sanitary point of view. Met.

  In addition, the biological purification method using aerobic microorganisms in the middle temperature range by supplying oxygen underground shown in Patent Document 4 is not accompanied by an increase in pathogenic bacteria for humans and the like. This is a purification technology having an aspect that impairs the value of groundwater as a water resource from a sanitary point of view.

  Thus, some of the conventional in-situ pollution purification countermeasure technologies have some technical problems with respect to the environmental impact. In particular, chemical and biological methods that carry out purification in a shorter time and more effectively tend to shift the underground aquifer environmental conditions to force them to conform to the optimum conditions for purification. There are concerns about the occurrence of secondary damage due to clogging of the aquifer due to oxidation deposits and groundwater flow direction fluctuations. In addition, there are many issues regarding the impact on the environmental aspects including our living sphere, such as concerns about the increase of pathogenic bacteria, environmental impact due to the generation of malodorous substances and harmful gases, and the impairment of the value of groundwater as water resources. It was.

On the other hand, the pumped water method shown in Patent Document 5 is a physical purification method that seems to have less environmental load because it exclusively pumps contaminated groundwater and discharges sewage after decontamination.
However, this technology has the aspect of pumping a large amount of uncontaminated groundwater having a value as a water resource from around 360 degrees together with a slight amount of contaminated water, and as a result, producing a large amount of diluted contaminated water that impairs the value as a water resource. It is a technology, and there are almost no cases of reuse of treated water after purification treatment, and there is a fact that the value of groundwater as water resources and much of valuable water resources are lost.
Although this technology has been pointed out in the past as to the purification period and cost-effectiveness of purification, it also has a problem of losing the resource value of unused non-polluted water, and leaves much room for improvement. It was.

  By the way, in recent years, the Ministry of Land, Infrastructure, Transport and Tourism and Ministry of Health, Labor and Welfare have led the promotion of effective use of rainwater, sewage treated water, groundwater, etc. as miscellaneous water. The Law Enforcement Regulations on Securing of Waste "and the" Manual on Recycling Water Quality Standards, etc. " The standard for the reuse of miscellaneous water includes coliforms and the like as designated items. Specific bacteria such as coliforms and pathogenic bacteria that are indicators of fecal contamination (hereinafter referred to as specific bacteria. Are any bacteria that have harmful effects on humans, such as coliform bacteria, pathogenic bacteria, bacteria producing odors and harmful substances, etc.) It is recognized as an important indicator for judging the pros and cons of.

  In general, the objective of the present invention from such a background is a resource such as contaminated groundwater, which is different from conventional pollution control measures such as simply purifying soil groundwater contamination or discarding groundwater after purification as wastewater. We decided to build a pollution control system with a new concept of purifying pollution premised on the regeneration of value.

In addition, in order to purify pollution assuming the production of miscellaneous water as a regeneration of the resource value of contaminated groundwater etc., it is important to decontaminate specific bacteria in addition to contamination with specific chemical substances. .
In order to efficiently purify these two groups of pollutants efficiently in the present invention, in addition to the function of purifying specific chemical substances, underground (underwater) that contributes to the growth of specific bacteria and the maintenance of populations. We focused on the removal of organic matter.

  For example, underground (underwater) using a group of microorganisms that have a higher growth ability than this specific bacterium and can expect a decrease in the number of specific bacteria due to growth competition for the utilization of organic matter in the underground (underwater). It is assumed that there is a technical requirement that satisfies the conditions such as removal of organic substances, the microorganism group having a metabolic function for various organic substances, and contributing to purification of specific chemical substances.

  In order to meet such technical requirements, we focused on thermophilic bacteria that grow in a high temperature environment exceeding 55 degrees Celsius and are characterized by high metabolism and rapid growth. An object of the present invention is to construct a system having a purification function against both contaminations by substances or bacteria.

By the way, the conventional techniques have proposed a method for purifying the contamination by heating the soil groundwater contaminated part as shown in Patent Documents 6 to 11 to form a high temperature region. It was a technology that was included in the category of conventional pollution control concepts such as simply purifying or discarding groundwater after purification as wastewater.
The technologies described in these patent documents are not purification technologies based on the premise of reducing contamination of both specific bacteria or chemical substances using at least thermophilic bacteria, and the invention aimed by the present invention is based on the basic concept. There was no matching technology until the choice of technology method.

  The gist of the present invention for achieving the above-described object is that, in the underground soil water contamination site, the hot water storage unit having a hot water temperature exceeding 55 degrees Celsius as described in claim 1 is used. Supply path of hot water supplied, underground warm tropics where hot water is embedded in the formation gap and its periphery, return path to hot water storage unit by pumping from underground warm tropics, and route from hot water storage unit to secondary supply A series of thermal regions including water is formed, and at least the growth of thermophilic bacteria is promoted to reduce soil groundwater contamination by specific bacteria or chemicals. In addition, the pumped groundwater is retained in the hot water storage unit. This is an in-situ pollution control system that promotes the reuse of such pumped water as miscellaneous water by further reducing specific bacteria therein.

  Further, the gist of the present invention is that a part of the hot water storage unit portion described in claim 2 is a power generation unit using hydrocarbons and a hot water storage unit using heat generated during power generation as a heat source. The in-situ contamination countermeasure system according to claim 1, wherein the in-situ contamination countermeasure system is configured as a part of a composite unit comprising:

  In addition, the gist of the present invention is that, as described in claim 3, the soil groundwater contamination is a soil groundwater contamination, and the series of soil groundwater contamination is assumed to occur in the site. The occurrence of soil groundwater contamination can be detected by forming a thermal region in advance, carrying out fresh water derived from pumped water, and periodically performing pollution monitoring in the pumped water. The in-situ pollution control system described in 1.

  According to the in-situ pollution control system for contaminated groundwater according to claim 1 of the present invention, a series of thermal regions are formed to promote the growth of at least thermophilic bacteria and prevent soil groundwater contamination by specific chemical substances or bacteria. Reduction can be achieved. In addition, by purifying contamination methods by thermophilic bacteria in such a thermal region, and purifying the purification methods utilizing the various features unique to the high temperature environment shown below, It is possible to efficiently carry out fresh water that encourages reuse of such pumped water as miscellaneous water.

  For example, by constructing a route for injecting and collecting hot water into the contaminated formation, it is possible to minimize the residual of the injected material in the underground and the load on the underground environment. In addition, by forming a certain thermal area in the in-situ purification area, the water permeability of the area will be improved, allowing efficient collection of contaminated water and easy supply and recovery of purification materials to the in-situ area. Can be aimed at. By facilitating the supply and recovery, it is possible to minimize the residue of the purification material in the underground environment, which has been a problem in the prior art, and achieve pollution purification with a low environmental load.

  In addition, by making the amount of hot water injected and pumped appropriately, even in an aquifer where a groundwater flow exists, it is possible to form a constant thermal region that minimizes the impact on the external groundwater flow. By setting the in-situ purification countermeasure area in this category, it is possible to implement a purification countermeasure that minimizes the load on the underground environment partially or temporarily.

  In addition, for organic chemical contamination with heavy oil, cutting oil, etc., the viscosity of heavy oil and cutting oil is reduced by forming a constant thermal area in the in-situ purification area. The effect of desorption from oil components such as oil film / oil odor component, BTEX component and mixed volatile organochlorine compound component and metabolism by thermophilic bacteria using it is promoted by changes in properties and plasticity, and efficient purification is achieved. You can plan.

Further, in the case of contamination with heavy metals or organochlorine compounds, the extraction of these contaminations can be promoted by forming such a thermal region and promoting the growth of thermophilic bacteria. In other words, the presence of heavy metals and organochlorine compounds in the subsurface is in a state where most of them are adsorbed by refractory organic substances such as humic substances contained in the formation, excluding the distribution in NAPL and groundwater.
By promoting the decomposition of this hardly-degradable organic substance by the high metabolic ability of thermophilic bacteria, the adsorption of heavy metals and organochlorine compounds is suppressed, and the extraction of these contaminants is promoted and the phase is shifted to the groundwater flow. By effectively collecting the contaminated groundwater that has undergone this phase shift, it is possible to implement effective pollution countermeasures.

  Furthermore, it is known that the bio / chemical reaction generally doubles when the temperature increases by 10 degrees (Celsius), and the temperature exceeding 55 degrees Celsius in the present invention is increased in this thermal region. By achieving this, the reaction speed is improved by several to 10 times compared with the biological purification method and the chemical purification method performed at the groundwater temperature (approximately 10 to 20 degrees Celsius) in the conventional technology. Compared with technology, purification can be performed very quickly.

  Further, according to the in-situ contamination pollution control system according to claim 2 of the present invention, the generated heat generated from the power generation unit using hydrocarbons as a heat source for hot water storage is used, but the generated heat is generated from this power generation unit. Electricity can be positively used for purification processing.

  For example, heavy metals and the like cause a passive / passive mode change depending on the Eh / pH condition, but the Eh / pH condition of the hot water to be injected is subject to purification by electrochemical operation using electricity. If the conditions of the movable region, such as heavy metals, are used, it is possible to carry out a positive extraction operation from the contaminated formation. Subsequently, the Eh / pH condition of the pumped water containing the extracted heavy metal is transferred again to the passive condition of the metal by electrochemical operation using electricity, and the recovery is performed together with the coagulation sedimentation treatment. By doing so, a series of heavy metal treatments can be achieved.

  In particular, for ionic heavy metals that can be easily extracted without setting Eh / pH conditions, the electricity and ion exchange membranes, bipolar membranes, etc., derived from such power generation units are provided on the ground after pumping. By means of the ion selection process, it is possible to efficiently purify ionic heavy metals and the like.

  Similarly, the Eh / pH condition of the hot water to be injected is set to a condition that is favored by a thermophilic bacterium having a contamination resolution, and further, a nutrient salt and, if necessary, an electron donor / acceptor are dissolved in the injected water. Thus, efficient biological decontamination can be carried out using a thermophilic degrading microorganism that can use the electron donor / acceptor as a dominant species.

  At this time, if it is possible to set up a groundwater circulation system in which a part of the pumped water is injected again in the thermal region, the reduced electron acceptor in the pumped water is oxidized with electricity derived from such a power generation unit. By performing injection after forming an oxidized electron acceptor, it is possible to effectively use the electron acceptor through repeated regeneration through electricity regeneration.

  In addition, by supplying hydrogen generated by electrolysis of water as an electron donor to the in-situ purification area via injection, a large amount of organic matter is injected underground to obtain the same effect. It is possible to promote the growth of thermophilic degrading bacteria without increasing the environmental load as in the prior art.

For example, in the purification of organochlorine compounds, it is possible to promote the growth of microorganisms specialized in dechlorinating bacteria that can use this organochlorine compound as an electron acceptor and hydrogen as an electron donor. Acetic acid or the like may be added as a source, and vitamin B12 or the like may be added to promote purification.
The conventional anaerobic dechlorination method was a purification method with a high risk of pathogenicity that proliferates a wide variety of miscellaneous bacteria that are concerned about the presence of pathogenic bacteria because mainly miscellaneous organic substances were used instead of hydrogen. By using hydrogen, dechlorination bacteria that are not pathogenic bacteria are dominant species, and environmental pollution can be effectively purified with less environmental impact.

  Similarly, by supplying the generated oxygen as an electron acceptor of a specific thermolytic microorganism, it is possible to promote the growth of the specific aerobic thermolytic bacteria.

  Furthermore, when pumping up groundwater that remains contaminated, using electricity from such power generation units, etc., purification by photocatalyst and ultraviolet irradiation, purification by ozone, purification by oxidation / reduction reaction on the surface of the electrolytic electrode, origin of electrolysis Decontamination of organic compounds remaining in pumped groundwater is carried out particularly efficiently by purifying water with hydrogen peroxide and ultraviolet radiation, purifying with ozone derived from electrolysis and OH radicals generated from hydrogen peroxide, etc. be able to.

On the other hand, by forming a certain thermal area in the in-situ purification area, organic substances present in the thermal area are mainly used by thermophilic bacteria that grow quickly, so the growth of specific bacteria is suppressed by competition of these organic substances. can do.
In addition, an environment maintained at a temperature of more than 55 degrees Celsius strictly becomes a killing temperature for specific bacteria such as coliform bacteria and pathogenic bacteria that can grow in an intermediate temperature range. It is possible to reduce the risk of pathogen treatment and the pathogenic risk of treated water used for secondary use. As a result, the safety and hygiene of workers during the purification construction, the purification measures without impairing the resource value of groundwater, and the use expansion in the secondary use of treated water can be achieved.

  In addition, in the conventional purification method with pumping, the pumped contaminated water is generally treated through a bubbling treatment, etc., but the coliforms and pathogenic bacteria etc. Specific bacteria migrated and subsequently diffused into the surrounding atmosphere and environment, which could increase the risk of pathogenicity over a wide area around the site. For example, in the present invention, the temperature is maintained at 55 ° C or higher. After the specific bacteria are sterilized through the stagnation environment, the pumping water is carried out to minimize the diffusion of the specific bacteria into the surrounding atmosphere and environment.

  In addition, the bubbling treatment using hot water promotes the phase shift of the volatile pollutants to be treated to the bubbling air due to its high temperature, so compared to the bubbling treatment at the medium temperature in the prior art. Remarkable purification efficiency can be obtained.

  In this way, in addition to the effect of promoting the growth of thermophilic bacteria and reducing pollution by forming a certain thermal area including the hot water storage unit on the ground in the in-situ purification measures area using hot water, , Improvement of water injection / pumping efficiency by increasing the permeability of hot water, pumping mechanism capable of recovering injections, temperature sterilization of specific bacteria in area and hot water, gas-liquid distribution change of pollutant chemicals, etc. As a result, it is possible to recycle the contaminated groundwater into an extremely efficient water resource while reducing the environmental burden.

  By the way, in the composite unit that combines the hot water storage unit and the power generation unit, there is a small general-purpose unit for home use (trade name: ENE-FARM, ECO-WILL, etc.). In the case of small-scale pollution, it is possible to construct a small-scale pollution countermeasure system using this small general-purpose unit, and various applications are possible in view of the pollution status and scale.

  For example, wide-area groundwater contamination by organochlorine compounds in the Minami Suita area of Suita City will reach a wide area of several hundred meters or more in October 2009, and most of the pollution is in urban areas where houses are densely packed. However, in the case of wide-area pollution existing in such urban areas, public acceptance is obtained on the premise of intensive groundwater pollution countermeasures using conventional technology due to problems such as land rights / noise / environmental impact / health risks It was very difficult to do.

  In such a case, the environmental impact and health of the present invention can be reduced by implementing a distributed groundwater pollution countermeasure in which a very small pollution control system using such a small general-purpose unit for home use is placed in each house. Since there are few risks and the land rights / noise problem is a distributed process, it does not become a big problem, and it is possible to set up an excellent environment that makes it easy to obtain such public acceptance. Particularly effective pollution countermeasures can be developed for wide-area pollution in such urban areas.

  In addition, according to the in-situ contamination countermeasure system for contaminated groundwater according to claim 3 of the present invention, by installing and operating such a system before the detection of contamination, it is possible to prevent soil groundwater contamination. Preventive measures can be taken to prevent expansion.

  Soil groundwater contamination is generally caused by leakage of specific chemicals used on the ground from the surface to the ground. The specific chemical substances present on the ground are designated for storage and discharge by various laws and regulations, and are generally under quantity control. In addition, it is common on the ground that preventive measures are taken to prevent diffusion such as waterproof floors and oil breakwaters in case of leakage or careless handling.

  Claim 3 has the same concept as the above-mentioned preventive measures for preventing the diffusion of pollution using a waterproof floor or an oil breakwater on the ground, and the groundwater by pumping and injection forming the thermal region according to the present invention. It is positioned as a preventive measure that prevents the spread of pollution to the underground environment through efficient operation of the system.

  In addition, by decomposing and removing persistent organic substances contained in underground soil in areas where contamination is expected by the high metabolic action of thermophilic bacteria, it is possible to absorb contamination to the soil as much as possible. By suppressing, contamination can be easily recovered by such pumping water.

  By operating the preventive measures for pollution diffusion to the underground environment according to the present invention, it is possible to prevent human health damage, environmental impact, loss of land assets and groundwater resource value caused by pollution diffusion. In addition, the pumped water generated by this precaution can be reused as miscellaneous water for effective utilization of water resources.

  In addition, as in the case of Suita City's urban wide-area pollution described above, if it is anticipated that the pollution will be widespread due to groundwater flow, the pollution control system of the present invention will be installed in the existing contaminated area, However, it is possible to take comprehensive pollution countermeasures against wide-area pollution by operating the pollution countermeasure system from the preventive viewpoint according to claim 3 for areas where contamination is expected in the future. .

It is a conceptual diagram of the in-situ pollution countermeasure system which is this invention.

  Hereinafter, embodiments representative of the present invention will be described. FIG. 1 is a conceptual diagram of an in-situ contamination countermeasure system according to the present invention.

  The in-situ contamination countermeasure system for contaminated groundwater according to the present embodiment includes an injection 2 of hot water stored in the hot water storage unit 1 and a pumping water via the hot water storage unit 1 that maintains a hot water temperature exceeding 55 degrees Celsius. 3 to form a series of thermal regions 5 including a purification countermeasure area 4 that is a soil groundwater contamination site through return to the hot water storage unit unit 1, and at least promotes the growth of thermophilic bacteria, In addition to reducing pollution caused by chemical substances, the pumped water stays in the hot water storage unit 1 and the specific bacteria in the pumped water are further sterilized by temperature sterilization. Thus, the pumped water is encouraged to be reused as miscellaneous water. Moreover, it becomes possible to make the miscellaneous water 6 by making the amount of water of this injection | pouring 2 and the pumping water 3 into the injection | pouring 2 <pumping water 3 and surplus collection | recovery of the groundwater 7 by the pumping water 3.

  Here, the hot water storage unit 1 has a system configuration in which the injected water and the pumped water are heated in the container by direct and indirect heating. As a direct heating method, use hot water generation by city gas, propane gas, electricity, solar heat, etc. As an indirect method, use a hot water generation function by heat exchange such as waste heat generated by steam, cogeneration, etc. it can.

  The hot water storage unit 1 may use the hot water storage unit in only one tank (hereinafter referred to as a primary hot water storage unit), but in addition, a plurality of subunits (hereinafter referred to as hot water storage subunits) may be used as necessary. In combination, the main function of the hot water storage unit 1 is achieved by purifying specific bacteria or chemical substances efficiently, or by heating non-contaminated water not derived from contaminated groundwater.

In the latter example, it is assumed that re-penetration of treated water derived from contaminated groundwater, such as a specific facility defined by the Water Pollution Law, is regulated. In such cases, contaminated groundwater such as rainwater is used. The non-originating water 8 is used as the hot water through the primary hot water storage unit and then used for the injection 2, and the pumped water 3 produces the miscellaneous water 6 through the hot water storage subunit.
In this way, by incorporating the hot water storage unit 1 composed of a plurality of primary hot water storage units and hot water storage subunits into the system, the present invention in which the thermal region 5 is maintained without re-permeation of water derived from contaminated groundwater. Can be implemented.

  The hot water storage sub-units may be heated by a single heat source in each sub-unit, or the hot water of the primary hot water storage unit is used as a heat source to concentrate hot water through a heat exchanger or the like. As long as it is an effective heating technique capable of maintaining the hot water temperature in the hot water storage unit 1 at a temperature of 55 degrees Celsius or higher, the means is not questioned.

Moreover, when using the system which has the electric power generation unit using the hydrocarbon of Claim 2, this system is equipped with the hot water generation system using the waste heat generated at the time of electric power generation with the hot water storage tank, This hot water storage tank It may be effectively used as a primary hot water storage unit.
However, depending on the hot water storage tank included in the system having the power generation unit, there is a model in which the passage of groundwater is not preferable. In such a case, the hot water storage subunit described above is used.

  In addition, when using equipment which requires power supplies, such as a pumping pump, a blower blower, or the warming of the hot water storage unit 1, over a long period of time, there is a concern that an electric charge increases and a running cost increases. In addition, when it is difficult to use the existing commercial power source, such as when the contaminated area has been cleared, the basic charge and installation of the utility poles will increase the initial cost of the purification work. It leads to.

In such a case, the introduction of a cogeneration system having a hydrocarbon-based power generation unit according to claim 2 is actively promoted to improve energy efficiency, thereby reducing the running cost and the initial cost. Like.
The in-situ pollution control system according to the present invention is a system with a high thermoelectric ratio that makes heavy use of hot water, and a cogeneration system that can use waste heat generated by power generation for hot water without waste in order to obtain the amount of power required for purification measures. It is desirable to make effective use of

  In addition, since the power generation unit using hydrocarbons uses a fuel source with established supply channels or sales channels for city gas, LP gas, etc., it should be used stably regardless of time regardless of location. Has the advantage that On the other hand, in cogeneration systems such as the use of waste heat from industrial gas turbines and other waste heat or solar heat, there are many cases where the location and time are limited. Operation is limited to very limited use.

  As described above, power generation units using hydrocarbons have characteristics that are excellent in the stability of supply of electric power and heat, but are roughly classified into two types, fuel cell type and engine generator type, depending on the power generation method. In comparison with the current model, the same type of machine shows a tendency that the output of the engine generator type is high for both power and heat, but the model selection by these methods depends only on the pollution control system at each pollution site, and it takes It is necessary to select appropriately according to the operation status of the system, the thermoelectric ratio, and the like.

  By the way, this in-situ contamination countermeasure system is characterized in that a hot region 5 is formed in the in-situ purification countermeasure area via injection 2 and pumped water 3 of hot water stored in the hot water storage unit 1. And the pumped water 3 implements efficient purification by making each deployment position appropriate according to the pollution distribution situation in the purification countermeasure area 4.

  In addition, as the water injection facility for performing injection 2, specifically, for example, an injection well and its piping (supply path) are applicable. For the pumping facility for performing pumping 3, specifically, for example, a pumping well and its piping (return path) These are connected to the hot water storage unit 1 respectively.

  For example, if the contamination is a hot spot that is mainly present in the aquifer, the injection well is connected to the pumping well so that a high recovery rate can be achieved with respect to the injection hot water while considering the direction of the groundwater flow. The thermal region 5 is formed so as to surround the purification countermeasure area 4 where contamination is present, and setting is made so that purification concentrated on the contaminated site can be achieved.

  It is assumed that contamination is a hot spot that mainly exists in the aquifer, and there are cases where there is no purification option other than degrading bacteria that prefer medium purification, but in such cases, injection is performed as described above. A pair of injection / pumping wells installed upstream of the pumping well in the direction of the groundwater flow form a thermal region 5 surrounding the purification area 4 where contamination is present, and this pair of injection / pumping / Inside the straight line connecting the pumping wells, another pair of injection / pumping wells is installed to form respective circulation areas formed by the inner shell and the outer shell.

This inner shell area is a medium-temperature water-flowing area that encloses the purification countermeasure area 4, and achieves higher-efficiency purification with degrading bacteria or the like that prefer the inner temperature inside. On the other hand, specific bacteria or chemical substances partially leak into the outer shell through the diffusion and flow down from this medium temperature water-flowing area. By reducing chemical substances, we will attempt to purify pollution with minimal environmental impact.
Moreover, after purifying a specific chemical substance, by stopping the inner shell injection 2 / pumped water 3, the thermal region 5 formed by the outer shell injection 2 / pumped water 3 is expanded to the area of the inner shell. Therefore, groundwater soil contamination by specific bacteria remaining in the inner shell area can be efficiently reduced.

  On the other hand, when the contamination is mainly present in the aquifer and in the downstream area away from the hot spot, the pumping well is installed in the groundwater flow improvement flow, and the injection well is installed downstream of the pumping well along the direction of the groundwater flow. After collecting the contaminated stream in the pumping well, after processing, it is discharged from the downstream injection well, part of the discharged treated water flows down along the surrounding groundwater stream, and the other is recovered again in the pumped well. Such a thermal region 5 is formed, and recovery having directivity with respect to the contaminated flow is sought, and setting is made so as not to cause excessive pumping involving a large amount of clean groundwater.

  In addition, when the contamination reaches a saturated aquifer through the unsaturated zone, for example, as described in Japanese Patent No. 3728510, around the boundary between the underground saturated zone and the unsaturated zone A wide-area fluid path layer including a large number of gaps communicating with each other is installed along with the present invention, and various injections 2 and pumping 3 are carried out in conjunction with the present invention. By carrying out various forms, efficient purification specialized in contaminated parts is carried out.

  In addition, the arrangement | positioning of the installation of the injection | pouring 2 mentioned above and the installation of the pumping water 3 is only a very limited example, and it is soil groundwater contamination with the hot water injection | pouring 2 and the pumping water 3 of this invention. Needless to say, the present invention is within the scope of the present invention as long as it is a method for performing a fluid operation for forming a series of thermal regions 5 including the purification countermeasure area 4 as a part. The hot water is not limited to heated water but also includes liquids containing some solute or insoluble matter in the water. Of course, the thing which supplied gas, such as air and oxygen by warm air or aeration, is also contained.

  By the way, this in-situ pollution control system can cope with the purification of many specific harmful substances stipulated by the Soil Contamination Countermeasures Law, but in particular, the purification of the first type volatile organic compounds and the second type heavy metals. Suitable for It is also suitable for purification of oil films, oily odors, mineral oils, etc. derived from mineral oil as stipulated in the Guidelines for Countermeasures against Oil Pollution.

  The first type of volatile organic compounds and related compounds to be purified here are carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, 1,3-dichloro Propene, dichloromethane, tetrachloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, benzene, vinyl chloride monomer, toluene, xylene, ethylbenzene, 1,4-dioxane, chloroform, trans-1,2- Examples include dichloroethylene, 1,2-dichloropropane, p-dichlorobenzene and the like.

  Purification of these volatile organic compounds and related compounds can be achieved by the decomposition and acceleration of extraction by thermophilic bacteria in the in-situ pollution control system of the present invention, as well as hot water extraction, a pumped-bath method under high temperature conditions, a chemical purification method, etc. Is used in combination as necessary. An appropriate construction method is selected in view of the contamination status, underground environmental conditions, and the like, and highly efficient purification is performed. At the same time, the in-situ contamination countermeasure system of the present invention can be used to produce secondary water that can be treated.

  Examples of the second type heavy metals and related compounds include cadmium, chromium, cyan, mercury, selenium, lead, arsenic, fluorine, boron, manganese, nickel, molybdenum, antimony, uranium and their compounds. It is done.

  Purification of these heavy metals of the second kind and related compounds can be achieved by the decomposition and the acceleration of extraction by thermophilic bacteria in the in-situ pollution control system of the present invention, as well as the electrochemical extraction and coagulation precipitation treatment for setting the Eh / pH conditions, A purification method using a combination of ion exchange membranes or the like can be used in combination as necessary. An appropriate construction method is selected in view of the contamination status, underground environmental conditions, and the like, and highly efficient purification is performed. At the same time, the in-situ contamination countermeasure system of the present invention can be used to produce secondary water that can be treated.

  In addition, hydrocarbon components such as petroleum-based fuels, polycyclic aromatic hydrocarbon compounds and the like can be mentioned. Examples of oil contamination to be purified here include crude oil, heavy oil, light oil, kerosene, oil having a composition equivalent to gasoline, waste cutting oil, waste lubricant oil and grease used for metal processing and equipment maintenance. And the like. Examples of the polycyclic aromatic hydrocarbon compound include naphthalene, anthracene, phenanthrene, pyrene, fluoranthene, chrysene, benzofluoranthene, and benzopyrene. Moreover, the soil pollution countermeasure system of this invention has the effect of reducing the oil content not only from the oil film and oily odor resulting from the low molecular oil content in these various pollutants.

  The purification of hydrocarbon components such as petroleum-based fuels and related compounds can be carried out by decomposing and promoting extraction by thermophilic bacteria in the in-situ pollution control system of the present invention as well as hot water extraction, pumping of water under high temperature conditions, etc. Combined as necessary. An appropriate construction method is selected in view of the contamination status, underground environmental conditions, and the like, and highly efficient purification is performed. At the same time, the in-situ contamination countermeasure system of the present invention can be used to produce secondary water that can be treated.

  In addition to the above-mentioned specific pollutant chemical substances, for example, the Industrial Safety and Health Act and the PRTR Law (Act on Understanding the Release of Specific Chemical Substances to the Environment and Promotion of Improvements in Management) and Related Laws In-situ pollution countermeasures of the present invention in which various other purification methods can be used based on the use of thermophiles Needless to say, the application of the system is effective.

  Note that the present invention is positioned as a versatile in-situ pollution control system that is effective not only when the above-described contaminants exist alone, but also for contamination in which multiple contaminants are mixed. .

  Further, the present invention is characterized by forming such a thermal region and promoting at least the growth of thermophilic bacteria to reduce soil groundwater contamination by specific bacteria or chemical substances. However, there are no thermophilic bacteria that degrade specific chemical contamination, and it may be difficult to implement the present invention. In such a case, thermophilic bacteria with good permeability in the aquifer are cultured on the ground beforehand, suspended in the injection water and inoculated into the underground contaminated area, the same as when indigenous bacteria existed An effect can be obtained.

  Here, thermophilic bacteria capable of degrading specific chemical contamination to be injected include G. stearothermophilus, G. thermomodenitrificans, and Geobacillus thermogluco. Examples include thermophilic bacterium species belonging to the genus Geobacillus, such as Sidan (G. thermoglucosidans), Geobacillus thermoleovorans (G. thermomoleovorans), and the like.

  In addition, the present invention is a process whose purpose is water production that can be secondarily used as miscellaneous water for contaminated groundwater, and the conditions for the miscellaneous water include the number of coliforms, pH, odor, turbidity, and appearance. Needless to say, it is possible to produce fresh water that meets the prescribed standards.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

[Example 1]
In this experiment, hot water of 55 degrees Celsius is supplied from a water bath simulating a hot water storage unit to a contaminated soil column simulating an aquifer in the purification countermeasure area to form a simulated temperate region, and flows out from this column. Set up a test zone in which a series of hot water circulation system is constructed to return this treated water to the water bath after purification of contaminated water, and a control zone where only the temperature is 15 degrees Celsius under the conditions of this test zone Thus, the difference in purification performance between the two and the difference in the number of coliform bacteria in the treated water were compared. The setting of 15 degrees Celsius simulates a general groundwater temperature. From this comparison, a study was conducted on the effectiveness and inventive step of the purification method of the present invention, which is an experimental group, with respect to the purification method at a medium temperature, which is the mainstream in the prior art as a control group.

The test procedure is shown below.
(A) This test apparatus has a water bath simulating a hot water storage unit, a glass column simulating a contaminated aquifer (effective length 25 cm), injection / injection in an incubator capable of constant temperature setting of 55 degrees Celsius and 15 degrees Celsius. In addition to a stainless steel piping system simulating a pumping well and its piping, it is equipped with a ventilation unit and an ion exchange membrane unit as main equipment as a decontamination function.
In addition, an AC 100V power supply device imitating a power generation unit and a syringe pump for column water flow were installed outside the incubator. In addition, the stainless steel pipe from the syringe pump to the column water is about 5m long, and it is put together in a coiled winding state in the incubator, and heat exchange is performed so that the water flow is equivalent to the temperature in the incubator when the column flows. Was set to be achieved. Furthermore, the water flow set in the syringe pump was subjected to the test after collecting raw water from a water bath in the incubator and adding a predetermined nutrient salt described later.
In general, the flow path of this system is syringe pump → glass column → air unit → ion exchange membrane unit → water bath, and the circulation of water flow is achieved by collecting raw water in the syringe pump from the water bath. It was.
By the way, if it is an original purification system, in addition to the addition of this nutrient salt, an operation of adding oxygen gas generated by electrolysis of water using electricity derived from a power generation unit or the like to the water solution is included. This time, the operation was omitted here for the convenience of the test system, and instead the oxygen gas was substituted for the water flow by replacing the air in the air unit with oxygen gas instead of air. The simulated groundwater used in the experiment was replaced with dechlorinated tap water.

  (B) For the preparation of simulated contaminated soil, a sandy soil boring sample forming an aquifer in which 0.73 mg / L was detected as the elution concentration of hexavalent chromium was used. Contaminated soil A is prepared by mixing 0.005 weight ratio of mixed oil obtained by mixing A heavy oil and C heavy oil at equal weight with respect to the weight ratio 1 of this sandy soil. As a harmful bacterial source represented by 1), a mixture of bran and dry whey in equal weight was mixed in a contaminated mixed soil A at a weight ratio of 0.01 to prepare a contaminated mixed soil B. In addition, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, 1,3-dichloropropene, dichloromethane, tetrachloroethylene, 1,1,1-trichloroethane, 1,1, Using a standard solution containing 2-trichloroethane, trichlorethylene, and benzene, the mixture was added to and mixed with the contaminated mixed soil B so that each would have a negative fifth power ratio of 1 × 10. Trial contaminated soil was created.

  (C) Subsequently, the sample-contaminated soil was filled in a glass column, and water was passed from a syringe pump in an upward flow from the bottom of the column. The water flow rate and the water flow frequency were adjusted so that the water flow rate was 50 cm / day as the average column passage speed. The water was supplied from raw water derived from a water bath in which nitric acid, phosphorus and potassium salts were dissolved. This addition of nutrients is performed by measuring the concentration of nitric acid, phosphoric acid, and potassium in the return liquid returned to the water bath through the column to determine the excess and deficiency, and determining the supply concentration, supply amount, and frequency. Adjustment was made in a timely manner, and the target was set to minimize the outflow of nutrients in the return liquid.

  (D) The baffle tank is equipped with a downflow oil separation tank as the first stage, the baffle using oxygen gas is implemented in the second, third, and fourth stages, and a water discharge pump is provided as the fifth stage. Then, storage of treated water flowing out from the fourth stage due to overflow and transfer of treated water to the ion exchange membrane unit were performed. In the ion exchange membrane unit, the ionic lysate was removed through the cation exchange membrane and the anion exchange membrane and returned to the water bath.

(E) After the test was started, the water bath and the sample water after passing through the column were collected over time, and the following analysis was performed. MPN method (Ministry of Health, Labor and Welfare) using the concentration of heavy metals and volatile organic pollutants in accordance with the method described in Notification No. 46 of the Environment Agency in 1991, and coliform group concentration using Corritage EL-10 (manufactured by Actec) In accordance with Notification No. 261, “Methods stipulated by the Minister of Health, Labor and Welfare based on the provisions of the Ministerial Ordinance on Water Quality Standards”, pH, odor, and turbidity are measured according to the same method, and the appearance is visually observed. Was judged.
On the other hand, the contamination concentration in the test-contaminated soil before and after the test is measured as the elution concentration according to the above analysis, and the oil content and oil film / oil odor in the soil are measured by the usual method indicated in the Ministry of the Environment Oil Pollution Control Guidelines. Furthermore, the number of coliforms was measured according to the above.

  (F) Two series of the above test systems were prepared, one system as an experimental section with a set temperature of 55 degrees Celsius, and the other system as a control section with 15 degrees Celsius imitating the groundwater temperature, A parallel experiment was conducted. The experimental results are shown in Tables 1 to 4.

  As a result, as is clear from Table 1, in the experimental group having a thermal region of 55 degrees Celsius according to the present invention, compared with the control group at 15 degrees Celsius, which is a conventional technique, against volatile compounds and heavy metal contamination, The effectiveness in terms of the purification rate was shown. In addition, the volatile organochlorine compound concentration and heavy metal concentration in the water bath were not detected throughout the period (data not shown).

  In addition, in the evaluation items for the treated water after passing through the column with respect to the standard items required as miscellaneous water as shown in Table 2, that is, the number of coliforms, pH, odor, turbidity and appearance, The water quality of the experimental plots on the 10th and 20th days after that, except for the detection of coliforms at an early stage, all met the criteria. On the other hand, in the control group, the coliform group was detected in all water samples during the test period.

  From the results of the above test, it can be seen that the 55 ° C constant temperature experimental zone having a thermal region has a remarkable effect on the reduction of the number of coliforms as well as the effect of prompt purification against volatile compounds and heavy metal contamination. It was.

  In addition, Table 3 shows the results of water production in a water bath simulating a hot water storage unit portion set at a strictly high constant temperature at 55 degrees Celsius, and was observed on the first day of the experimental section in Table 2. Since the detection of coliforms was not detected in the water bath, it was found that there was an effect of reducing the number of coliforms by this strict high constant temperature setting.

  In addition, according to the analysis results of the soil in the column after the end of the test, as shown in Table 4, in the experimental zone, which is the effect of the thermal region, particularly purifying as compared with the control zone, which is a conventional technique, is achieved for reducing the oil content. I understood that. The consumption of added nutrients (data not shown) and the increase in thermophilic bacteria growing at 60 degrees Celsius were observed, suggesting the possibility of purifying oil by thermolytic bacteria. . It was also found that the coliform group has a similar bactericidal and reducing effect.

[Example 2]
This example shows the results of a simple preliminary test for determining the applicability of the purification method implemented at a site where complex contamination with trichlorethylene and cutting oil was detected. Although it is not a full-scale purification example, it is an example that was performed in parallel with a conventional method that could be used as a control.
In this test, we compared the purification performance of (1) the combination of microbial degradation by normal temperature oil-degrading bacteria and pumping treatment, and (2) the decomposition / pumping treatment under high temperature conditions, which is typical as a conventional construction method. Carried out.

The test procedure is shown below.
(A) First, in order to match the initial conditions of both experiments, the injection / pumping well set used in each test system is brought close to each other in the vicinity of the center of the contamination with a width of 3 m, and further, each is set along the groundwater flow. In the upstream, an injection well was separated by 5 m, and in the downstream, a pumping well was installed.

  (B) In addition, the pumping treatment is performed on the groundwater pumped to the ground by a submersible pump (AC100V drive) through an oil-water separator and an activated carbon tank, and then the treated water after the activated carbon treatment is underground through an injection well. The groundwater circulation system to be reinjected into the plant was constructed in both test systems. The circulation rate was basically 3 L / min. When the injection well was blocked, the well was backwashed and washed with dilute hydrogen peroxide. In addition, in both test sections, nutrient salt addition and management procedures were performed according to Example 1.

  (C) Moreover, Ecowill (ECG-155: manufactured by Nagafu Seisakusho) was used as an AC 100V power source and a hot water supply source. In the production of high-temperature groundwater, the periphery and bottom of a 150 L stainless steel container are kept warm, the groundwater in the stainless steel container is warmed through a heat exchanger using hot water derived from Eco Will, and the groundwater temperature is 65 degrees Celsius. It was carried out in a simple hot water storage unit with a constant temperature function that would be constant temperature. In addition, an overflow pipe was installed at the top of this simple hot water storage unit, and it was set so that a constant continuous injection was achieved by this overflow.

(D) Before the start of the test and 30 days after the start of the test, drilling is conducted near the midpoint connecting the pumping well and the injection well in each test system, and the contamination concentration and the number of general bacteria are measured. The purification performance of methods was compared.
Each injection water was collected every 15 days, and trichlorethylene concentration, coliform group, pH, odor, turbidity, appearance, etc. were measured according to a standard method. The experimental results are shown in Tables 5 and 6.

  As a result, as is apparent from Tables 5 and 6, it is clear that the test zone in which the thermal region according to the present invention is formed can purify the soil at a very high speed against soil groundwater contamination as compared with the test zone at room temperature. It was. In addition, the quality of the circulating water in the high-temperature test section has been changed to a state where it can be used as miscellaneous water for at least 15 days and later, and it can be reused as miscellaneous water very early. Has been demonstrated in a previous test.

  As mentioned above, although the Example of this invention was described, a concrete structure is not restricted to the Example mentioned above, Even if it is a change and addition in the range which does not deviate from the summary of this invention, it is contained in this invention. For example, in the embodiment described above, both a specific chemical substance and bacteria such as coliform bacteria are targeted for purification, but at least one of them may be targeted for purification.

  When pursuing pollution purification that considers environmental impacts, such as on the premise of the restoration of the resource value of contaminated groundwater, etc., and when pursuing efficient pollution purification using a high temperature region of 55 degrees Celsius or higher, The present invention is particularly applicable.

DESCRIPTION OF SYMBOLS 1 ... Hot water storage unit 2 ... Injection 3 ... Pumping water 4 ... Purification measures area 5 ... Thermal area 6 ... Miscellaneous water 7 ... Ground water 8 ... Water which does not originate in contaminated ground water

Claims (3)

Via a hot water storage unit that maintains a hot water temperature of more than 55 degrees Celsius, the supply path of hot water supplied to the underground soil groundwater contamination site, the subterranean tropics and its periphery, Forming a series of thermal zones including a return path from the hot tropics to the hot water storage unit and a route from the hot water storage unit to the secondary supply,
At least promote the growth of thermophilic bacteria to reduce soil groundwater contamination by specific bacteria or chemical substances, and in addition, the pumped groundwater is retained in the hot water storage unit to further reduce specific bacteria in the pumped water In-situ pollution control system characterized by prompting reuse of such pumped water as miscellaneous water.   Part of the hot water storage unit is configured as a part of a composite unit consisting of a power generation unit using hydrocarbons and a hot water storage unit that uses heat generated during power generation as a heat source, and purifies the power from the power generation unit. The in-situ contamination countermeasure system according to claim 1, wherein the in-situ contamination countermeasure system is used as an apparatus power source.   The soil groundwater contamination is soil soil groundwater contamination, and the series of thermal regions are formed in advance in a site where the occurrence of such soil groundwater contamination is assumed, and water production derived from pumping is performed, and The in-situ pollution control system according to claim 1 or 2, wherein the occurrence of soil / groundwater pollution can be detected by periodically performing pollution monitoring in pumped water.

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