JP2007028907A - Greening soil and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide greening soil excellent in fertilizer balance and obtained by sufficiently insolubilizing or washing alkaline components falling within coal ash, and also inexpensively insolubilizing or washing heavy metal falling within the coal ash, and to provide a method for producing the greening soil. <P>SOLUTION: The greening soil is obtained by fermenting a mixture of coal ash, undecomposed plant-derived material, fermentation auxiliary material promoting fermentation of the undecomposed plant-derived material and a neutralizing agent under an aerobic condition. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a greening soil and a method for producing a greening soil.

Coal ash contains an alkaline component that inhibits plant growth. Therefore, in order to use coal ash for soil for greening, it is necessary to insolubilize or wash the alkaline component. In addition, coal ash may contain heavy metals that cause environmental pollution. And in order to utilize this coal ash for the soil for tree planting, it is also necessary to insolubilize or wash heavy metals. Therefore, for example, techniques shown in Patent Documents 1 to 3 have been developed as techniques for utilizing such coal ash for soil for greening.
JP 2002-212554 A JP 2001-220271 A JP 2000-8037 A

  However, the conventional techniques have the following problems. That is, it is difficult to sufficiently insolubilize or wash the alkaline components contained in the coal ash with the conventional technology, and a large amount of coal ash is used for the greening soil, such as using the coal ash as a base material for the greening soil. There is a problem that it cannot be used. In addition, in the conventional technique, in order to insolubilize or wash heavy metals contained in coal ash, it is necessary to add an insolubilizing material or to perform chemical treatment, which increases the cost and lengthens. Furthermore, the conventional land transfer for greening lacks the fertilizer balance, and there is a problem that it is not necessarily suitable for land transfer for greening.

  The present invention has been made in view of the above problems, and its purpose is to sufficiently insolubilize or wash alkali components contained in coal ash and to insolubilize heavy metals contained in coal ash at low cost and in a short period of time. Or it is providing the manufacturing method of the soil for greening which can be wash | cleaned, and was excellent in the fertilizer balance, and the soil for greening again.

  In order to solve the above problems, the present invention aerobic a mixture of coal ash, undecomposed plant generating material, fermentation auxiliary material that promotes fermentation of the undegraded plant generating material, and a neutralizing agent. Let it be fermented under conditions.

  According to such a configuration, since the alkali component contained in the coal ash can be sufficiently insolubilized or washed, a large amount of the coal ash can be used for the greening soil. Moreover, when heavy metal is contained in coal ash, the heavy metal can be insolubilized or washed at a low cost and in a short period of time. Moreover, the land transfer for greening of this invention is excellent in the fertilizer balance, and is suitable for the land transfer for greening.

The coal ash includes heavy metals.
The heavy metal includes at least one of boron, lead, zinc, cadmium, mercury, and hexavalent chromium.
Moreover, the said neutralizing agent shall contain phosphate fertilizers, such as a superphosphate lime and a heavy superphosphate lime.

  In addition, the present invention performs aeration on a mixture of coal ash, undecomposed plant generating material, fermentation auxiliary material that promotes fermentation of the undegraded plant generating material, and a neutralizing agent. We will ferment the plant-generated material of decomposition.

  According to the present invention, the alkali component contained in the coal ash is sufficiently insolubilized or washed, the heavy metal contained in the coal ash can be insolubilized or washed at a low cost and in a short period of time, and the fertilizer balance is excellent. The soil for greening and the manufacturing method of the soil for greening can be provided.

  Hereinafter, the method for producing the soil for greening and the soil for greening according to the present invention will be described.

=== Soil for greening ===
The soil for greening of this embodiment ferments a mixture of coal ash, undecomposed plant generating material, fermentation auxiliary material, and neutralizing agent (hereinafter also referred to as “fermented material”) under aerobic conditions. It is a thing. And the coal ash of this embodiment contains the alkaline component which inhibits the growth of a plant, and also contains the heavy metal which causes environmental pollution. Examples of such heavy metals include boron, lead, zinc, cadmium, mercury, hexavalent chromium, and arsenic.

  Further, the undegraded plant generating material is an undegraded plant generating material, and the plant generating material contains organic matter such as grass wood chips and garbage, and indigenous bacteria necessary for fermentation are attached. Examples of such plant generating materials are materials derived from plants such as plant trunks, branches, twigs, roots, etc., and in the case of grass-wood chips, they are generated due to dam construction and road construction in mountainous areas. For example, pruned branches and leaves of deforested trees, felled roots, green spaces, roadside trees, parks, planted trees, dead trees, waste wood generated from construction sites, sawdust, fallen leaves, cut grass, and cut grass. In addition, it is also possible to use litter mixed with raw garbage, food raw material waste generated from food factories and business establishments, or livestock manure such as cattle and horses generated from livestock production establishments. In addition, litter is laid on the floor of a barn to protect livestock and absorb manure, and generally uses rice straw called litter, but sawdust, pulverization park, crushed rice husk. Also used.

  Fermentation auxiliary materials are materials that promote the fermentation of undegraded plant-generated materials, such as fermented nutrients such as wheat bran and powder, fermenting microorganisms that ferment crushed vegetation, pH buffering agents, humus Those containing minerals such as acids, calcium compounds and magnesium compounds can be employed. As fermentation auxiliary materials, those containing saccharides capable of producing natural polymers such as arabinose and galactose are particularly preferable. More specifically, “Shuttle Component (trade name)” or “Accel” manufactured by Nisshin Flour Milling Co., Ltd. There are “component (product name)”, “assist component (product name)”, “calorie component (product name)”, and the like. Such a fermentation auxiliary material, when mixed with coal ash, promotes fermentation under aerobic conditions because it forms moderate continuous voids and promotes the activity of fermenting bacteria. In addition, said natural polymer has the effect | action similar to a chelating agent, and has the effect | action which insolubilizes the heavy metal contained in coal ash.

  Further, the neutralizing agent is for neutralizing the alkaline component contained in the coal ash, and is preferably a chemical fertilizer containing a large amount of soluble phosphoric acid or phosphate. Those containing a phosphate fertilizer such as acid lime are preferred. The neutralizing agent containing phosphate fertilizer contributes to the improvement of fertilizer balance and also has an effect of insolubilizing heavy metals contained in coal ash.

  Since the above-mentioned soil for greening can fully insolubilize or wash the alkaline component contained in coal ash, a large amount of coal ash can be used for the soil for greening. Furthermore, since heavy metals contained in coal ash can be insolubilized or washed at low cost and in a short period of time, it does not cause environmental pollution. In addition, it is excellent in the balance of fertilizers such as phosphoric acid and potassium, and is suitable for soil transfer for greening. In order to maximize the above effect, the blending ratio of the fermentation material is adjusted as appropriate. For example, 90% by weight of coal ash is mixed with 10% by weight of undecomposed plant generating material, and the mixture 5% by weight of fermentation auxiliary material and 3% by weight of neutralizing agent are added.

=== Manufacturing method of soil for greening ===
Next, a method for producing a greening soil according to the present embodiment will be described with reference to FIGS. 1, 2A and 2B. FIG. 1 is a basic flow diagram for explaining a method for producing greening soil, and FIGS. 2A and 2B are explanatory diagrams when the method for producing greening soil is carried out at a construction site.

  As shown in FIG. 1, the manufacturing method of the soil for greening of this embodiment is comprised by each process of S101-S107. First, the coal ash 10 is transported to the fermentation yard X and filled (S101). Further, after transporting the vegetation (cutting tree) to another place in the fermentation yard X and performing primary crushing with a self-propelled wood crusher or the like (S102), the vegetation quality A crushed material (hereinafter also referred to as “cutting material chip”) is manufactured (S103). Then, after the vegetation crushed material (corresponding to “undegraded plant generating material”), fermentation auxiliary material, and neutralizing agent are added to the embankment (S104), they are mixed and stirred by a mixer or the like. (S105) The soil is turned over and sprinkled, and after the fermentation process (S106), the greening soil 1 is produced (S107). In the fermentation process (S106), the above-mentioned fermentation material is adjusted to an appropriate moisture condition and aeration is performed to ferment the undegraded plant-generating material under aerobic conditions (curing period: 1 month). More than 3 months). However, when aeration is performed, the temperature of the fermentation material should not be excessively lowered. Moreover, in order to adjust fermentation conditions appropriately, it is preferable to homogenize the whole amount by stirring and mixing at least once during the curing period.

  As a form which implements such a greening soil manufacturing method at a construction site, there are a case where it is carried out in a small scale form (see FIG. 2A) and a case where it is carried out in a large scale form (see FIG. 2B). Each will be described below.

<When implementing in a small form>
As shown in FIG. 2A, when the method for producing greening soil is carried out in a small-scale form, for example, when the construction site has a width of about 4 to 5 m, a height of about 2 m, etc., first, the dumped coal The ash 10 is crushed with the backhoe 31, and the fermentation auxiliary material 30 and the neutralizing agent 40 are sprinkled on it. Next, the attachment of the backhoe 31 is exchanged from the bucket 33a to a special bucket 33b (for example, a galvanizer) having a stirring and crushing function such as a hydraulic jaw crusher, and the special bucket 33b is used. The coal ash 10, the fermentation auxiliary material 30, and the neutralizing agent 40 are primarily mixed. Further, the felled wood chips 20 which are undecomposed plant generating materials are crushed into the primary mixture 32, and the primary mixture 32 and the felled wood chips 20 are secondarily mixed in the same manner. The secondary mixture 35 is accumulated in a predetermined place. In addition, since the specific gravity of the coal ash 10, the felling material chip 20 and the fermentation auxiliary material 30 is significantly different, it is usually difficult to uniformly mix them. However, it becomes easy to mix these uniformly by stirring using the special bucket 33b.

On the other hand, a compost yard 36 is prepared by installing a blower, an air pipe, a crushed stone, a wire net, and the like, and the secondary mixture 35 is deposited on the compost yard 36 and cured under aerobic conditions while performing aeration. Since the amount of air necessary for fermentation (for example, 0.9 m ³ / min) is ensured by aeration, the above-described curing can be performed even in the winter when the fermentation conditions are severe. In the deposited secondary mixture 35, a thermometer, a pH measuring device, and the like are embedded, and the curing conditions are appropriately maintained and managed while measuring the temperature, pH, and the like. When the secondary mixture 35 is cured in this manner, the greening soil of the present invention is produced. In addition, during the curing of the secondary mixture 35, the backhoe 31 is used to appropriately cut back. This switching makes it possible to maintain the aerobic condition. Through the above steps, the greening soil can be produced on a small scale.

<When implemented in a large-scale format>
In addition, as shown in FIG. 2B, when the method for producing a greening soil is implemented in a large-scale form, for example, when the greening soil is produced continuously and in large quantities, a self-propelled soil improvement machine 37 is used. (For example, Hitachi Construction Machinery SR-G2000, etc.), various machines such as backhoes 31a, 31b, and large dump 38 are used. First, coal ash 10 generated at a thermal power plant or the like is loaded on a large dump 38 by a backhoe 31a, transported to a predetermined temporary storage site, and accumulated. On the other hand, a felled material chip 20 is prepared by collecting felled material from thinning or dam driftwood to maintain the artificial forest, or by chipping the waste material into chips. Next, the accumulated coal ash 10 is introduced into the self-propelled soil improvement machine 37 by the backhoe 31b, and the felled wood chip 20, the fermentation auxiliary material 30 and the neutralizing agent 40 are put into the self-propelled soil improvement machine 37. In In the self-propelled soil improvement machine 37, the coal ash 10, the felling material chip 20, the fermentation auxiliary material 30 and the neutralizing agent 40 are uniformly stirred and mixed. In these mixtures 41, the soil blocks are finely divided (for example, a particle size of 20 mm or less), and are ejected and deposited outside the self-propelled soil improvement machine 37. In addition, by moving the self-propelled soil improvement machine 37, the deposition location can be changed as appropriate. And the soil for greening is manufactured by curing the deposited mixture 41 on aerobic conditions. However, for the sake of convenience of explanation, the same reference numeral 41 is given to the mixture before curing and the soil for greening. In the case of carrying out in a large-scale configuration, a large amount of greening soil 41 is sown with a backhoe 31 after curing, and aeration pipes, crushed stones and the like are placed below the ground in order to make it easier to load the soil into a large dump 38 or the like. It is preferable to install it. Through the above steps, the greening soil 41 can be manufactured on a large scale.

  The greening soil 41 produced in this way can be applied to a green space. For example, it can be leveled with a bulldozer 39 or the like at a construction site, and the flat ground can be greened by filling. Furthermore, an inclined surface can also be greened by using the soil 41 for greening as a spraying material. When greening an inclined surface, a machine, equipment, etc. used in a general spraying method may be used (for example, a spraying machine 90, a spraying hose 91, an extension hose 92, an air compressor 93, a generator 94, Belt conveyor 95, weighing mixer 96, material hopper 97, tire excavator 98, etc.).

  In addition, according to the present embodiment, by simultaneously fermenting coal ash that is inorganic waste and undecomposed plant generating material that is organic waste (for example, felled wood chips), It is possible to simultaneously achieve the reduction of waste and the production of greening soil, which is a useful material. Therefore, society will further advance to zero emissions and contribute to environmental improvement.

It is a basic flow figure for explaining the manufacturing method of the soil for tree planting. It is explanatory drawing in the case of implementing the manufacturing method of the soil for greening with a small scale form. It is explanatory drawing in the case of implementing the manufacturing method of the soil for greening with a large-scale form.

Explanation of symbols

10 Coal ash 20 Crushed vegetation (undecomposed plant material)
30 Fermentation auxiliary material 40 Neutralizing agent 41 Greening soil

Claims (8)

  Greening characterized by fermenting a mixture of coal ash, undegraded plant-generating material, a fermentation secondary material that promotes fermentation of this undegraded plant-generating material, and a neutralizer under aerobic conditions Soil.   The soil for greening according to claim 1, wherein the coal ash contains heavy metal.   The soil for greening according to claim 2, wherein the heavy metal contains at least one of boron, lead, zinc, cadmium, mercury, and hexavalent chromium.   The said neutralizing agent contains phosphate fertilizers, such as a superphosphate lime and a heavy superphosphate lime, The soil for tree planting in any one of Claim 1 to 3 characterized by the above-mentioned.   Aeration is performed on a mixture of coal ash, undecomposed plant generating material, a fermentation auxiliary material that promotes fermentation of the undegraded plant generating material, and a neutralizing agent, and the undecomposed plant generating material is A method for producing a soil for greening, which is fermented.   The said coal ash contains heavy metal, The manufacturing method of the soil for tree planting of Claim 5 characterized by the above-mentioned.   The method for producing a greening soil according to claim 6, wherein the heavy metal includes at least one of boron, lead, zinc, cadmium, mercury, and hexavalent chromium. The said neutralizing agent contains phosphate fertilizers, such as a superphosphate lime and a heavy superphosphate, The manufacturing method of the soil for greening in any one of Claim 5 to 7 characterized by the above-mentioned.