JP6528188B2 - Method of producing functional compost - Google Patents

Description

  The present invention relates to a method for producing functional compost using sewage sludge residue pellets. In particular, the present invention relates to a method for producing functional compost from depolymerized sewage sludge residue produced in a plant or facility having a process of depolymerizing sewage sludge residue.

  The amount of sewage sludge produced in Japan is gradually increasing with the spread of sewerage, and according to the data of fiscal 2008 of the Ministry of the Environment, the amount is 2.21 million tons / year on a dry weight basis. The generation amount of sewage sludge is said to account for about 20% of the total industrial waste, and many of them are disposed of in landfills after burning, so it is important for business owners to secure disposal destinations and sludge treatment costs, etc. There is a need to reduce running costs. However, the amount of sewage sludge generated is increasing year by year, so it is difficult to secure landfills and waste disposal sites.

In recent years, recycling of sewage sludge residue has been promoted, and sewage sludge residue that has been dewatered is used as a biomass resource such as fertilizer conversion and fuel conversion.
As an example, the Ministry of Land, Infrastructure, Transport and Tourism is implementing the B-DASH project (Sewer Innovative Technology Demonstration Project), and is focusing on solving these problems.

  The characteristics of biomass resources of sewage sludge residue are (1) that a certain amount always occurs with human living environment, (2) that components and conditions are constant, (3) fuel, fertilizer, cement raw material It is known that it is possible to use it. Practical application research for practical use of the sewage sludge treatment system developed by Mitsubishi Nagasaki Kiko Co., Ltd., which is one of the B-DASH project of the Ministry of Land, Infrastructure, Transport and Tourism 2012, making use of this feature is the eastern sewage treatment plant in Nagasaki City. Was implemented. This system is a new sludge reduction technology combining hydrothermal reaction technology and high-speed methane fermentation technology, and this system is called metasaurus (see Patent Documents 1 and 2). In this system, the amount of sludge discharged was successfully reduced by a factor of 5 compared to the existing system, and it was possible to reduce the disposal cost significantly when disposing of it. However, although the amount of dewatered sludge generated has been significantly reduced, disposal is mainly performed.

  Then, the effective utilization method of the sewage sludge residue treated with low molecular weight was examined from the viewpoint of the zero emission of the area including the sewage treatment plant. The low molecular weight treated sewage sludge residue generated by this system contains nitrogen, phosphorus and potassium components as elements necessary for the growth of plants, so this sewage sludge residue is used as a fertilizer or soil conditioner Attempts have been made, and this sewage sludge residue is currently registered with the Ministry of Agriculture, Forestry and Fisheries Registered Fertilizer as "East Nagasaki Demonstration No. 1".

  However, this fertilizer has a high moisture content and the presence of bacteria, and has a problem that the ammonia odor is also strong. In addition, since the compost is not completely matured, there is a concern that if it is used as it is for soil, it may cause problems such as growth problems in crops.

JP, 2012-200691, A JP 2012-200692 A

  The object of the present invention is to produce useful mature compost containing a large amount of fulvic acid and humic acid without the above problems in a short period of time.

  In order to solve these various problems, the inventor of the present invention researches the improvement of the above-mentioned fertilizer, the bacteria having two different temperature active areas, such as Bacillus bacteria and lactic acid bacteria, in the inner and surface portions of sewage sludge residue pellets respectively. By carrying out the fermentation and fermenting the microbe-supporting sewage sludge residue pellet, it is found that useful functional compost having no problems as described above can be efficiently produced in a short period of time, and the present invention is completed. It came to Moreover, it discovered that it could ferment at high speed by natural fermentation, without using a special apparatus and a heating apparatus which are used by the conventional high-speed-fermentation processing technique.

That is, the present invention is as follows.
[1] A method for producing a compost comprising: carrying Bacillus bacteria on the inside of a sewage sludge residue pellet and fermenting the bacteria-carrying sewage sludge residue pellet having a lactic acid bacterium on the surface layer.
[2] The compost-carrying compost according to the above-mentioned [1], wherein the bacteria-supporting sewage sludge residue pellet is prepared by adding Bacillus bacteria to the sewage sludge residue pellet, drying the surface layer portion of the pellet, and then adding lactic acid bacteria. Manufacturing method.
[3] A method for producing a compost according to the above [1] or [2], characterized in that the bacteria-supporting sewage sludge residue pellets are piled up and fermented.
[4] A planarizing step of planarizing the sewage sludge residue pellet, a bacillus addition step of adding Bacillus bacteria to the sewage sludge residue pellet that has undergone the planarization step, and a sewage sludge residue pellet that has undergone the Bacillus bacteria addition step The pellet surface layer drying step of drying the surface layer portion, the lactic acid bacteria addition step of adding lactic acid bacteria to the sewage sludge residue pellet that has undergone the pellet surface portion drying step, and piled up the bacteria-supporting sewage sludge residue pellet that has passed the lactic acid bacteria addition step The method for producing a compost according to any one of the above [1] to [3], which comprises a pile-up step and a fermentation step of fermenting the bacteria-supporting sewage sludge residue pellet subjected to the pile-up step.
[5] The process according to the above [4], wherein the fermentation process comprises a turning-back step of turning back the bacteria-supporting sewage sludge residue pellet, and a water adjusting step of adjusting the water content of the bacteria-supporting sewage sludge residue pellet. How to make compost.
[6] The method for producing compost according to any one of the above [1] to [5], which is fermented for 14 to 20 days.
[7] The method for producing compost according to any one of the above [1] to [6], wherein the sewage sludge residue pellet is obtained by pelletizing a low molecular weight treated sewage sludge residue.
[8] The method for producing a compost according to any one of the above [3] to [7], wherein the center part excluding the top and the lower part of piled bacteria-supporting sewage sludge residue pellets is covered with a covering material for fermentation. .
[9] A method for fermenting pellets comprising: carrying Bacillus bacteria in the inside of the pellet and carrying on a pile the bacteria-carrying pellets on which the lactic acid bacteria are carried in the surface layer.

  According to the method of producing functional compost of the present invention, useful mature compost containing a large amount of fulvic acid and humic acid can be produced in a short period of time.

FIG. 5 is a flow diagram of an embodiment of a method of producing a functional compost of the present invention. It is a photograph which shows a mode that the plant root has approached into the functional compost (fermented pellet) manufactured by the manufacturing method of this invention. It is a photograph which shows a mode that the plant root has approached into the functional compost (fermented pellet) manufactured by the manufacturing method of this invention. It is a figure which shows the temperature change of the sewage sludge residue pellet at the time of the fermentation process in Example 1. FIG. It is a figure which shows the nitrate nitrogen concentration of soil at the time of using the functional compost of this invention. In manufacture of the functional compost of Example 7, it is the schematic explaining the state which covers and ferments the center part of the piled microbe-supporting sewage sludge residue pellet with a vinyl sheet (coating material). It is a figure which shows the temperature change of the sewage sludge residue pellet at the time of the fermentation process in Example 1 (without a coating | coated) and Example 7 (with a coating | coated).

  The method for producing functional compost according to the present invention is not particularly limited as long as it is a method of carrying Bacillus bacteria on the inside of sewage sludge residue pellets and fermenting bacteria-carrying sewage sludge residue pellets on which lactic acid bacteria are carried on the surface part. The functional compost produced by the production method of the present invention is not a mature compost, and can be used in solid, semi-solid, or liquid state, and can be used as a soil conditioner .

  Sewage sludge residue pellets (prior to carrying Bacillus bacteria and lactic acid bacteria) used in the functional compost production of the present invention may be those obtained by pelletizing sewage sludge residue, for example, one side or 5 diameters. The pellet of a rectangular solid or a cylinder of about 15 to 40 mm and a length of about 20 to 40 mm can be mentioned, and in consideration of transportation to the fermentation site, storage up to the fermentation treatment, etc., those having a water content of 20% or less are preferable. Such a pellet may be a pelletized sewage sludge residue to which general sewage treatment has been applied, but it is subjected to a molecular weight reduction treatment to reduce the molecular weight of difficultly degradable polymers such as lignin and cellulose. Preferably, the sewage sludge residue is pelletized. At the time of molecular weight reduction treatment, various organic resources such as food residue may be added. Examples of such molecular weight reduction treatment include hydrothermal treatment, ozone treatment, biological activated carbon treatment, ultrasonic treatment (for example, JP-A No. 2003-144097), and various treatments may be combined. As a specific example of the molecular weight reduction treatment by hydrothermal treatment, there can be mentioned a method using the hydrothermal reaction described in Japanese Patent Application Laid-Open Nos. 2012-200691 and 2012-200692.

  The preparation of the bacteria-supporting sewage sludge residue pellet is not particularly limited as long as Bacillus bacteria can be supported inside and the lactic acid bacteria can be supported on the surface layer portion, and the method is not limited. After adding Bacillus bacteria to the sewage sludge residue pellet and drying the surface layer of the pellet, it is preferable to prepare by adding lactic acid bacteria, specifically, the planarization step (S1) described later, and the raw material water adjustment step The preparation method which has (S2), a Bacillus bacteria addition process (S3), a pellet surface layer part drying process (S4), and a lactic acid bacteria addition process (S5) can be illustrated.

  Moreover, as a fermentation method of the bacteria-supporting sewage sludge residue pellet in the method for producing functional compost of the present invention, it is not particularly limited as long as the method can ferment the bacteria-supporting sewage sludge residue pellet. From the viewpoint of efficiency, it is preferable to use a method in which the bacteria-supporting sewage sludge residue pellets are piled up and fermented. As a method of making it piled up and fermenting it, any method may be used as long as it piles up and ferments bacteria-supporting sewage sludge residue pellets, and as a form of piles, it may be conical, pyramidal, truncated conical, or truncated pyramidal. Or, a mountain-like shape in which these shapes are extended in a predetermined direction can be mentioned. Specifically, methods in a pile process (S6) and a fermentation process (S7) described later can be exemplified.

  As shown in FIG. 1, in the method for producing functional compost according to the present invention, for example, a flattening step (S1) for spreading sewage sludge residue pellets in a planar manner, and a raw material water adjusting step for adjusting moisture of sewage sludge residue pellets (S2), a Bacillus bacteria addition step (S3) of adding Bacillus bacteria to sewage sludge residue pellets that has undergone the planarization step (S1) and the raw material water adjustment step (S2), and sewage sludge that has passed the Bacillus bacteria addition step A pellet surface layer drying step (S4) for drying the surface layer portion of the residue pellet, and a lactic acid bacteria addition step (S5) for adding lactic acid bacteria to the sewage sludge residue pellet subjected to the pellet surface portion drying step (S4) The piled process (S6) which piles up the sewage sludge residue pellet which passed through (S5), and the fermentation process (S6) which ferments the sewage sludge residue pellet which went through the piled process (S6) ) Has a may have other steps. In addition, the fermentation step (S7) preferably includes a turning back step (S71) and a moisture adjustment step during fermentation (S72).

  The flattening step (S1) is a step of spreading the sewage sludge residue pellets in a planar manner, as long as the pellets are spread uniformly, and may be partially overlapped. This planarizing step makes it possible to attach the Bacillus bacteria to be added to the whole, and to suppress a rapid temperature rise due to the metabolism of Bacillus bacteria.

  The raw material water adjustment step (S2) is a step of adjusting the water content of the sewage sludge residue pellets, and it is not always necessary if the raw material pellets have an originally appropriate water content. In this step, the carrier to which Bacillus bacteria is applied is adjusted to a predetermined water content (water content) by applying water and drying if necessary. In this step, all or a part of the treatment may be performed simultaneously with the step of adding Bacillus bacteria, for example, a predetermined amount of water is added to sewage sludge residue pellets, and then Bacillus subtilis water is added to finalize the treatment. The amount of water may be adjusted, or the final amount of water may be adjusted by adding Bacillus dissolved water to the sewage sludge residue pellet without adding water to the sewage sludge residue pellet in advance. The moisture content of the sewage sludge residue pellets adjusted here is preferably 25 to 70% by mass, more preferably 30 to 60% by mass, and still more preferably 40 to 60% by mass. The water content referred to herein means the water content including the water when water is simultaneously added at the time of addition of Bacillus bacteria, and means the water content at the time of (immediately after) addition of Bacillus bacteria. By this step, the pellet can be swelled to allow the cells to penetrate to the inside of the pellet, and the activity of the cells can be enhanced.

  Moreover, this raw material water | moisture-content adjustment process may perform part or all of the process before the planarization process. That is, it is possible to adjust the water content before spreading it into a flat shape, and spread the water adjusted pellets into a flat shape.

  The bacillus addition step (S3) is a step of adding bacilli to the sewage sludge residue pellet that has undergone the planarization step (and the raw material water adjustment step), in a state in which bacillus is dissolved in a predetermined amount of water, It is preferable to add uniformly to the whole pellet. As described above, when the sewage sludge residue pellets are spread in a planar manner, it becomes easy to attach the Bacillus bacteria to the whole.

  Bacillus bacteria to be added in the method of the present invention include, for example, Bacillus subtilis, Bacillus tequilansis, Bacillus vallismortis, Bacillus mojavensis, Bacillus amyloliquefaciens, Bacillus subtilis subsp. Subtilis, Bacillus subtilis subsp. Among these, Bacillus subtilis var. natto (natto bacteria) is preferable. These Bacillus bacteria can be used individually by 1 type or in combination of 2 or more types. The method for obtaining Bacillus bacteria is not particularly limited, and commercially available products can be used. Also, for example, food itself containing Bacillus bacteria such as natto, or Bacillus bacteria isolated therefrom may be used.

  The pellet surface layer portion drying step (S4) is a step of drying the surface layer portion of the sewage sludge residue pellet, and is a step of supporting the Bacillus bacteria inside the pellet by drying the surface layer portion of the pellet. In this pellet surface layer portion drying step, for example, natural drying is performed for 12 to 48 hours after the addition of Bacillus bacteria, but the pellet group may be dried while being stirred if necessary. In the case of planar drying as it is, the upper and lower portions of the pellet group do not have a uniform dried state, but at least the upper portion of the pellet group is in a state where part of the surface layer of the pellet alone is dried. To dry.

  The lactic acid bacteria addition step (S5) is a step of adding the lactic acid bacteria to the sewage sludge residue pellet whose surface layer is dried, and adding the lactic acid bacteria from above to the pellet spread in a planar shape, the lactic acid bacteria in the pellet surface layer. It is a process to carry. As the lactic acid bacteria to be added, for example, Lactobacillus (Lactobacillus), Bifidobacterium (Bifidobacterium), Lactococcus (Lactococcus), Enterococcus (Enterococcus), Streptococcus (Streptococcus), Pediococcus (Pediococcus), Lactic acid bacteria of the genus Leuconostoc can be mentioned. These lactic acid bacteria can be used singly or in combination of two or more. The method for obtaining the lactic acid bacteria is not particularly limited, and commercially available products can be used. Also, for example, food itself containing lactic acid bacteria such as yogurt, or lactic acid bacteria isolated therefrom may be used.

  In addition, although addition of lactic acid bacteria is performed on sewage sludge residue pellets in a state of being spread at least in a planar manner, by performing again on sewage sludge residue pellets which are piled up in the next step, more whole pellets It is possible to give lactic acid bacteria to

  Bacillus bacillus is added to the sewage sludge residue pellet, which is a raw material, and after the surface layer of the pellet is dried, the lactic acid bacteria are added to support the Bacillus bacillus inside the pellet and to carry the lactic acid bacterium in the surface layer. It is possible to form a two-layer structure of two types of bacteria in the pellet. By using cells of two different temperature active regions, each cell is mutually activated, so that a physical heating device is not required, and a fermentation temperature of 60 ° C. to 70 ° C. can be obtained only by natural fermentation. It can be sustained.

  The pile-up step (S6) is a step of piling up sewage sludge residue pellets, for example, preferably performed within one hour after the completion of the addition of the lactic acid bacteria, and more preferably within 30 minutes. In this step, for example, it is preferable to form a mountain so as to wrap the planar pellet group from the outside, to form a mountain as high as possible, and to pile up at a repose angle is particularly preferable. Moreover, it is preferable to stack the pellet group in a mountain-like shape (in a state of being extended in a predetermined direction) to perform fermentation, since large amounts of fungus-supporting sewage sludge residue pellets can be efficiently fermented.

  The fermentation step (S7) is a step of fermenting the piled sewage sludge residue pellets, and if necessary, switching back (switching back: S71) and moisture adjustment (water adjustment during fermentation: S72) once or 2 Do more than once. That is, when the fermentation temperature of the pellet group is lowered, the feed back is performed and the water content is adjusted to achieve the supply of oxygen and the distribution of the cells to be averaged, thereby maintaining the uniform fermentation and the growth of useful microorganisms. Make it possible. In addition, the surface layer portion of the pellet becomes powdery and is separated from the pellet body by this turning back, and becomes a mixture of massive pellet and powder.

  In the present invention, since the fermentation is carried out in a piled state, a high temperature area is formed for a long time by the microorganism from the central part to the apex of the piled pellet group, and therefore useful microorganisms including Bacillus bacteria and lactic acid bacteria inside. Activity rises. In addition, regions having different temperature differences are formed in the outer surface layer portion and the deep layer portion, and active regions of cells having different temperature regions can be formed. For example, filamentous fungi grow in a layer 5 to 10 cm deep from the surface, and lactic acid bacteria and oxidizing bacteria grow inside the layer, and Bacillus fungi grow in the deep layer. The temperature in the vicinity of the surface layer is kept in a temperature range of about 30 to 45 ° C., and the temperature of the deep layer part is kept in a temperature range of about 60 to 70 ° C.

In the fermentation process, it is considered that the following action is caused in the pile-like pellet group, and it is considered that high-speed useful functional compost can be produced only by natural fermentation.
First, when we look at the activity of Bacillus bacteria and lactic acid bacteria carried on sewage sludge residue pellets, the activity temperature range of lactic acid bacteria is lower than that of Bacillus bacteria, so it becomes an accelerator for pellet fermentation, up to the activity temperature range of Bacillus bacteria. Raise the temperature. That is, first, the lactic acid bacteria having an active temperature range of 15 to 42 ° C. decompose the monosaccharide which is a water-soluble component in the surface layer portion of the pellet alone, and the temperature of the pellet alone is raised by the metabolic heat generated in the decomposition process. Furthermore, because lactic acid bacteria produce large amounts of lactic acid and antibiotics by metabolism, the environment around the surface of the pellet alone is acidified, so that other microorganisms that are not resistant to acid are not attracted, and antibiotics eliminate microorganisms such as bacteria. . The activity of the lactic acid bacteria in the surface layer of the pellet alone causes the temperature of the pellet alone to rise gradually, and the Bacillus bacteria (activity temperature range 20 to 65 ° C) that perform the activity in the high temperature range existing inside the pellet gradually start.

  The Bacillus bacteria decompose the organic matter inside the pellet alone and convert it to a monosaccharide, and the monosaccharide is used again by metabolism of lactic acid bacteria in the surface layer. The heat of metabolism generated by the decomposition of the organic matter of the pellet itself at the same time by a large number of these microorganisms raises the temperature of the deep part of the pile-like pellet group to 60 to 70 ° C. within a narrow range. By raising the temperature of the pile-like pellet group deep part to 60 to 70 ° C., it becomes possible to kill pathogens, bacteria, etc. having poor heat resistance. Furthermore, when the temperature of the pile-like pellet group deep part reaches the lactic acid bacteria death temperature, the lactic acid bacteria are killed, but since the killed lactic acid bacteria are used for metabolism of Bacillus bacteria, the Bacillus bacteria can be stably grown. It becomes possible to add metabolic byproducts such as lactic acid of lactic acid bacteria to pellet alone. However, since the outer surface portion of the pile-like pellet group does not reach the lactic acid bacteria death temperature, a large number of microorganisms including lactic acid bacteria and oxidizing bacteria are present compared to the deep layer portion. Thus, by using lactic acid bacteria and Bacillus bacteria in the fermentation process of the present invention, natural fermentation can be efficiently performed without the need for a heating device.

  On the other hand, when viewed as a whole in a pile of pellets, a large amount of filamentous fungi propagates in the early stage of piling up, and a thick layer of filamentous fungi with a thickness of 5 to 10 cm on the outer surface of the pile of pellets. After being produced, the filamentous fungi begin to proliferate throughout, while the growth of bacillus bacteria and the activity of metabolism of other oxidizing bacteria increase with the rise of internal temperature, and in the deep part, in the high temperature range of 60 to 70 ° C, A temperature difference of 30 to 45 ° C. in a low temperature range is generated in the side surface layer portion of the piled pellet group. Due to this difference in temperature difference, the activity of filamentous fungi active in the low temperature region becomes active in the surface layer part of the pile-like pellet group, and on the inside, the mixed activity area of lactic acid bacteria, oxidizing bacteria and bacillus bacteria becomes deep area In this case, Bacillus bacteria that are active in high temperature range are active.

  Also, in the deep part of the piled pellet group, aerobic fermentation is performed by useful microorganisms, and sugars, proteins, hemicelluloses and celluloses are decomposed and mineralized into water, carbon dioxide and ammonia, but some of them are microorganisms. Remains as a metabolite of Some of the generated water vapor etc. is released from the top, but it is not released from the side but a part from the top due to the high density layer of filamentous fungi on the top of the pile of pellets Water vapor containing metabolites that have not been collected is naturally convected inside the piled pellets. In the process of natural convection, the metabolite polymerizes to form a persistent compound, and the residue of the persistent substance such as lignin and tannin contained in the pellet reacts with the polymer of the metabolite to produce humic substances (fulvic acid and fulvic acid It produces humic acid). In addition, a part of the water vapor of the complexed metabolite is released from the top of the pile-like pellet group, so that the inside of the pile is depressurized, and by being depressurized, air is taken in from the gap of the side surface layer part Functions to promote aerobic fermentation of useful microorganisms inside the piled pellet group, and further causes a polymerization reaction.

  In the method of producing a compost according to the present invention, it is preferable to cover the center of the piled pellets except the top and the bottom with a covering material for fermentation. As the covering material, a sheet, a frusto-conical mold or the like can be mentioned, and it is preferable that the covering material is made of a material that blocks ultraviolet light.

  By covering and fermenting with a covering material, the pile-like pellet group is kept warm, the temperature inside rises, fermentation is promoted, and the fermentation of the pile-like pellet group proceeds more uniformly. That is, due to the heat retaining effect of the covering material, the temperature of the central lower portion (deep layer) of the pile-like pellet group in which the fermentation is difficult to proceed is elevated to promote the fermentation, whereby the water vapor etc. The air is released from the top of the mountain, and along with it, the outside air is introduced from the bottom side of the mountain. Furthermore, the introduction of ambient air activates the activity of oxidizing bacteria and the like to create a virtuous cycle in which internal fermentation is further promoted. In addition, the covering material prevents the diffusion of water vapor and the like generated by fermentation to the outside, thereby increasing the content of water vapor and the like contained in the compost to be produced, and the activated bacteria can be used to The ability to digest efficiently and increase the content of nitrate nitrogen inside the compost can enhance the fertilizing effect of functional compost. Moreover, ultraviolet rays can be prevented by the covering material, and it can prevent that a useful microbe (filamentous fungus etc. which inhabits the surface) at the time of fermentation is killed.

  In addition, in the method of producing a compost according to the present invention, air may be introduced upward from the lower center of the piled pellet group. Thereby, fermentation of the central lower part (deep layer part) of pile-like pellet groups which fermentation does not advance easily can be promoted. Alternatively, the amount of air introduced from the lower center of the piled pellet group may be increased, and the amount of air introduced around the pile group may be decreased, and air may be introduced from the entire lower part of the piled pellet group.

  In the method for producing a functional compost of the present invention, it can be used as compost equivalent to mature compost 14 to 20 days after the start of fermentation. It can be seen that the fermentation according to the method of the present invention proceeds at a high speed, as compared with the fact that the fermentation period in the production of conventional compost and Bokashi fertilizer is required for 1 to 2 months in the 60 to 65 ° C temperature range.

  The functional compost produced by the production method of the present invention contains 2-3 times more fulvic acid and humic acid than the raw material sewage sludge residue pellets. Fulvic acid and humic acid are valuable resources that are produced only in very small amounts in nature, and are substances that are said to take about 100 years to form a 1 cm deposit in nature. The production method of the present invention is characterized in that fulvic acid and humic acid which require time for such formation can be produced in an extremely short period of time.

  Further, the functional compost produced by the production method of the present invention has an effect of attracting small animals effective for soil improvement such as effective nematode and white mites, and further has an effect of propagating actinomycetes in the soil. In addition, when plants are grown using the functional compost (fermented pellets) produced according to the production method of the present invention, a phenomenon is observed that roots of the plants enter into the fermented pellets (FIG. 2 and FIG. 2). 3). The attraction of such nematodes and the introduction of roots is that animals and plants are recognized as high-quality natural soil, and it is proof that they are very close to very high-quality natural soil. is there.

  Such improvement of biota by the functional compost produced by the production method of the present invention greatly improves the physicochemical properties in the soil. Since the improvement of the soil environment affects the promotion of plant growth, quality improvement, disease resistance, etc., the quality improvement and yield of crops can be achieved by effectively using the functional compost produced by the production method of the present invention. It is possible to achieve business stability by improving the stability of the plant, improving convenience by integrating a single fertilizer, and establishing a low-cost production system. Furthermore, it will lead to the establishment of recycling agriculture, enabling sustainable agriculture.

  Also, the functional compost produced is composed of two types of powdered compost, which is degraded by the metabolism of useful microorganisms, and pellet-shaped compost, which contains a large amount of undegraded parts, which are mixed depending on the application. May be used separately or may be used separately.

  The functional compost which is a mixture of powdery and pellet-like produced by the production method of the present invention is easily decomposed by soil microorganisms when used as a fertilizer for cultivated plants in agriculture and forestry, and the expression of available nitrogen is Powdery substances of the early stage have a large effect on the initial growth of plants, and then they are stabilized because soil-like microorganisms decompose pellet-like substances containing a large amount of unproved nitrogen and the long-term availability of nitrogen is expressed. Exert an effect on plant growth.

  Further, another invention of the present invention is a fermentation method in which Bacillus bacteria are supported on the inside of the pellet and the bacteria-supporting pellet on which the lactic acid bacteria are supported on the surface portion is piled up and fermented. That's right. As the pellets used in the present invention, the above-mentioned sewage sludge residue pellets and other organic material pellets (animal excrement pellets, wood pellets) can be mentioned. According to the fermentation method of the present invention, fermentation can be performed in a shorter period than natural fermentation.

  Hereinafter, the present invention will be specifically described by way of examples, but the scope of the present invention is not limited thereto.

  As a raw material for sewage sludge residue pellets, "East Nagasaki Demonstration No. 1" (fertilizer registered by the Minister of Agriculture, Forestry and Fisheries) consisting of sewage sludge residues treated to be low in molecular weight was pelletized into a shape of about 10 mm in diameter and about 25 mm in length The thing was used.

First, about 1000 kg of sewage sludge residue pellets as a raw material was taken out from the flexible container, spread in a planar shape, and left for 1 week.
Under the present circumstances, the moisture content was measured in three places of the sewage sludge residue pellet after 1 week leaving-to-stand, and the average was computed. The moisture content is measured by using an infrared moisture meter FD-610 (Ket Scientific Research Co., Ltd.) of a heating / drying / mass measuring method at three points appropriately selected, and heating / drying for 30 minutes for 5 g of one sample. The water content was measured.

Water was added to the whole from the top of the sewage sludge residue pellets spread flatly after being left for 1 week, and water was added. Thereafter, Bacillus bacteria isolated from commercially available natto was dissolved in water, and the solution adjusted to 30 L was introduced into the entire sewage sludge residue pellet. Initially, only the upper part was wet, but after about 3 hours, it was wet to the lower part.
The water content was measured by the same method as described above immediately after introducing the Bacillus bacteria.

After drying the sewage sludge residue pellet to which Bacillus bacteria has been added for 12 hours, 10 L of water in which 200 mL of lactic acid bacteria (lactic acid bacteria cultured from rice bran) is dissolved is added from above the sewage sludge residue pellet to make it piled again. 10 L of water in which 200 mL of lactic acid bacteria were dissolved was sprayed over the whole, and 10 L of water was further sprayed.
At this time, measure the height and width of the pile, and install a thermometer (Don-Dori Co., Ltd. made by T & D Co., Ltd.) at a depth of 30 cm from the top of the piled sewage sludge residue pellets, temperature every 5 minutes Was continuously measured until the end of the fermentation treatment.

After fermentation for one week, the first round of turning back was performed, and after piling up, 100 L of water was added.
At this time, the height and width of the pile of sewage sludge residue pellets before and after switching were measured. In addition, the water content before turning back and the water content after turning back and addition of water were measured. About 5 g of water is collected from three 20 cm deep areas of half height of piles of pile-like pellets, and the moisture content is measured, and the infrared moisture meter FD-610 (Kett Science Co., Ltd.) Using a laboratory, 5 g of one sample was heated and dried for 30 minutes to measure the moisture content.

  After fermenting for another 5 days, a second turn was made, and after piling up, 100 L of water was added, and further fermented for 8 days to complete the compost treatment in the pellet.

  The compost was manufactured by the method similar to Example 1 except the point which does not perform leaving for 1 week in the state which extended the sewage sludge residue pellet taken out from the flexible container in planar shape.

  The moisture content of the pellets at the time of each measurement of Example 1 and 2 and the height and width of the pile when piled up are shown in Tables 1 and 2, respectively.

  Moreover, the temperature change of the sewage sludge residue pellet at the time of the fermentation process in Example 1 is shown in FIG.

  From FIG. 4, after several hours from the start of fermentation, the temperature rises and exceeds 70 ° C., and then the tendency to decrease until completion of functional compost is shown. Characteristically, the temperature is maintained at 60 ° C. or more for 5 days from the start of the fermentation period until the first turn back. When the fermentation temperature reaches 50 ° C. or less on the 8th day, turn back is performed, and when the temperature falls below 50 ° C. on the 14th day, turn back is performed. Since the fermentation temperature after the 14th day turning-back process has not risen so much, it becomes an indication of the completion of the fermentation process. In addition, it can be seen that the temperature inside the pellet group is rising after the initial stage and after the water adjustment. Generally, if the fermentation temperature continues at 60 ° C. to 70 ° C. for 2 days, it is considered that the bacteria, pathogens, etc. inside are killed. In the present technology, the state of primary fermentation (60 ° C. or more) is maintained for 5 days or more, so it is clear that it is a safe fertilizer. That is, in the treatment method of the present invention, it has become clear that natural fermentation can be efficiently performed without the need for a heating device or the like.

[Evaluation of functional compost manufactured in Example 1]
The functional analysis of the functional compost produced in Example 1 and the sewage sludge residue pellet (Comparative Example 1) used as a raw material were subjected to component analysis in a third party. In addition, for the analysis of fulvic acid and humic acid, the method of the International Society of Humic Substances was used. For analysis of cation exchange capacity, fertilizer analysis method 5.31.2 was used. For analysis of nitrate nitrogen and nitrite nitrogen, fertilizer analysis method 7.6 was used. Fertilizer analysis was used for carbon-nitrogen ratio analysis.
The results are shown in Table 3 below.

  As shown in Table 3, in the functional compost of Example 1, fulvic acid was about 3 times that of Comparative Example 1 and humic acid was about 2 times that of Comparative Example 1. That is, it has become clear that, by using the treatment method of the present invention, the raw material sewage sludge residue pellets are humified in a very short period of time.

  In addition, Li (2009; structure and function of water-soluble humic substances contained in cow manure compost) is compost after initial pretreatment fermentation for 9 days by 2 types of deposition type and agitation type (early stage And the amount of fulvic acid in the compost (late stage) at the end of the treatment stage of the secondary fermentation for 60 days, the amount of fulvic acid increases with the increase of the fermentation period in the deposition method, It is reported to decrease in the stirring system. In the conventional high-speed fermentation technology by agitation, processing is performed in a short period, and therefore, it is also mentioned that humification does not progress and it can not be expected to increase humic substances because microbial decomposition does not proceed. Although the present invention is a deposition method, the amount of fulvic acid is three times higher than that of the raw material despite the short processing period. That is, it became clear that humification by microbial decomposition progressed rapidly by using the treatment method of the present invention.

  Further, as shown in Table 3, the cation exchange capacity (CEC) of Example 1 was 63 meq / 100 g. Usually, it is said that the cation exchange capacity (CEC) must be 60 meq / 100 g or more as the judgment of the complete ripeness of the compost, and it can be judged that the functional compost of Example 1 is in a state of full ripeness. On the other hand, since the positive ion exchange capacity (CEC) of the pellet (raw material) of Comparative Example 1 is 51.8 meq / 100 g, it is in an unfinished ripe state. That is, by the 20-day fermentation treatment of Example 1, the unripened pellets (raw material) could be completely ripened.

  Functional compost (treated pellets) produced by the same method as in Example 1 is applied to the soil, and treated pellets recovered from the soil after cultivating romanesco are treated with fulvic acid (international humus) at a third party. Material Society Method) and cation exchange capacity (CEC) (fertilizer analysis method 5.31.2) were analyzed.

  As a result of analysis, the fulvic acid content of the treated pellet recovered from the soil was 2.5 mg / g, and the cation exchange capacity (CEC) was 53.6 meq / 100 g. The amount of fulvic acid of the treated pellet recovered from the soil was lower than that of the treated pellet before soil application because the fulvic acid contained in the pellet was used due to the formation of soil aggregate structure, crop growth, etc. It is considered to be. That is, it is considered that the produced humic substances were combined with the clay mineral by crosslinking iron or aluminum contained in the pellet or the soil to form a humic clay complex.

  The role of humus is to change the physical properties of the soil, that is, the organic acid of humus is sticky and solidifies fine particles and coarse particles such as soil clay to form a aggregate structure to change the physical properties of the soil. By forming the aggregate structure, drainage, water retention and air permeability become better. In addition, humus has the effect of enhancing the soil retention ability and pH buffering action of the soil. When the humus content is high, the negative charge becomes strong, and the amount of adsorption of cations also increases, so that the cation exchange capacity (CEC) increases. Humus also affects the soil biota. For example, it has the effect of increasing various kinds of microorganisms, and also has the effect of attracting small animals such as earthworms. In fact, it was confirmed that earthworms increased in the treated pellet application field, and effective nematodes and white mites were attracted to the treated pellets. Furthermore, the generation of geosmin, which is an odor emitted by actinomycetes, was confirmed in the field. That is, since the functional compost manufactured by this invention contains the substance which comprises humus, it became clear that it is effective in improving a soil environment.

Functional compost produced by the same method as Example 1 was applied to the soil to grow Chinese cabbage and ginseng. The results of measuring the soil hardness after cultivation are shown in Table 4. As a comparison, soil hardness after cultivating Chinese cabbage and ginseng in the same manner as in Example 3 was measured using a chemical fertilizer and cow dung instead of the functional compost of the present invention (Comparative Example 2). The soil hardness was measured after harvesting each crop using a Yamanaka-type soil hardness tester, measuring the soil hardness at a total of six locations at three locations above and below from the cross section of each ridge.
The results are shown in Table 4.

  From the results of Table 4, in the soil of Example 4, the hardness is low and the soil is soft. It is considered that the soil into which the functional compost of the present invention has been introduced forms a aggregate structure by humus.

  In the results of Table 3, the functional compost (treated pellet) of Example 1 was hardly detected with nitrate nitrogen and nitrite nitrogen, and was equivalent to the raw material pellet of Comparative Example 1, but the inventor From the experience so far, the following tests were conducted, considering that the supply of nitrate nitrogen (nitrate nitrogen) was increasing at the time of soil application.

A 22 L planter was filled with 16 kg of yellow fine-grained soil, to which 625 g of functional compost produced in the same manner as in Example 1 (nitrogen amount: 20 g / m ² ) was added and mixed. After that, 1 L of water was added. Hydrolysis was performed at intervals of 3 days. After mixing the soil daily, 100 g of the soil was collected and nitrate nitrogen was analyzed using a compact nitrate ion meter (LAQUAtwin B-741, manufactured by Horiba, Ltd.). As a comparison, using sewage sludge residue pellets (nitrogen amount 20 g / m ² ) and chemical fertilizer 200 g (nitrogen amount 20 g / m ² ) used as raw materials for compost, analysis of nitrate nitrogen was carried out in the same manner as Example 5. It carried out (comparative examples 3 and 4). The results are shown in FIG.

  As shown in FIG. 5, in the treated pellets of Example 5 and the raw material pellets of Comparative Example 3, the nitrate nitrogen concentration after 1 L of water is in a tendency to increase, but the water content decreases as time passes. At the same time, nitrate nitrogen concentration tended to decrease. On the other hand, the chemical conversion fertilizer of Comparative Example 4 showed an increasing tendency regardless of the moisture content. This difference is because the treated pellets of Example 5 and the raw material pellets of Comparative Example 3 are organic materials, and take longer to become nitrate nitrogen compared to chemical fertilizers. When the nitrate nitrogen concentration of the treated pellet of Example 5 and the raw material pellet of Comparative Example 3 were compared, it was revealed that the nitrate nitrogen concentration of the treated pellet was higher than that of the raw material. Further, in the treated pellets of Example 5 and the raw material pellets of Comparative Example 3, when the soil is dried, the activity of the microorganism is reduced, and therefore, it is considered that the nitrate nitrogen concentration is reduced. Therefore, in the treated pellet of Example 5, the organic components were decomposed by useful microorganisms (bacillus bacteria, lactic acid bacteria, oxidizing bacteria, etc.) in the process of producing functional compost, and the above-mentioned useful microorganisms were added in the production process. In order to attract small animals, which coexist with useful microorganisms (actinomycetes etc.) originally present in the soil after being put into the soil, and are able to grow smoothly and to roughly degrade the organic matter in the soil, It became clear that the expression of available nitrogen in the source was faster than that of the raw material.

  Spring cropped potatoes were grown using functional compost produced in the same manner as in Example 1. As a comparison, spring crop potatoes were grown under the same conditions using sewage sludge residue pellets, which are raw materials (Comparative Example 5). The number of potatoes per harvest, the number of potatoes and the total weight of the potatoes were calculated. The results are shown in Table 5.

  From the results of Table 5, when the functional compost of Example 6 is used, the growth of the crop is promoted even when compared with the sewage sludge residue pellet of the raw material which is the fertilizer registered fertilizer of the Ministry of Agriculture, Forestry and Fisheries, Functional compost proves to be a very useful fertilizer.

After piled up the pellets in the same manner as in Example 1, the central part excluding 30 cm from the top and 30 cm from the ground was covered with a vinyl sheet, and the pellets were fermented in the same manner as in Example 1 to produce functional compost (Figure 6).
The fermentation temperature and ammonia nitrogen content of the functional compost prepared in Example 7 and the functional compost prepared in Example 1 were compared. The results of fermentation temperature are shown in FIG. 7 and the results of ammonia nitrogen content are shown in Table 6.

  As shown in FIG. 7, it is considered that, by covering and fermenting with a coating material, piled-up pellet groups are kept warm and the internal temperature rises to promote fermentation.

  In addition, as shown in Table 6, the content of ammoniacal nitrogen in the compost produced in Example 7 is higher than that of the compost produced in Example 1. This is considered to be the result of covering a part of piled up pellets with blue sheet, thereby promoting the fermentation of the pellets and preventing the outflow of ammonia effective as a fertilizer effect.

The present invention has high industrial utility because it can produce a very useful functional compost.

Claims (10)

  A method for producing a fermented pellet characterized in that Bacillus subtilis is carried on the inside of a sewage sludge residue pellet and the bacteria-carrying sewage sludge residue pellet having a lactic acid bacterium carried on the surface portion is fermented.   The method for producing a fermented pellet according to claim 1, wherein the bacteria-supporting sewage sludge residue pellet is prepared by adding Bacillus bacteria to the sewage sludge residue pellet, drying the pellet surface portion, and then adding a lactic acid bacterium. .   The method for producing a fermented pellet according to claim 1 or 2, wherein the bacteria-supporting sewage sludge residue pellet is piled up and fermented. Planarizing the spread of sewage sludge residue pellets
A Bacillus bacteria addition step of adding Bacillus bacteria to sewage sludge residue pellets that have undergone the planarization step;
Pellet surface layer drying step of drying the surface portion of the sewage sludge residue pellet that has undergone the Bacillus bacteria addition step;
The lactic acid bacteria addition process which adds a lactic acid bacteria to the sewage sludge residue pellet which passed through the pellet surface layer part drying process,
A pile process that piles up bacteria-supporting sewage sludge residue pellets that have undergone the lactic acid bacteria addition process,
A fermentation process for fermenting the bacteria-supporting sewage sludge residue pellet that has been subjected to a pile process;
The method for producing a fermented pellet according to any one of claims 1 to 3, which comprises The fermentation process is
A turning back step of turning back the bacteria-supporting sewage sludge residue pellets,
A moisture adjustment step of adjusting moisture of the bacteria-supporting sewage sludge residue pellets,
The method for producing a fermented pellet according to claim 4, characterized in that   The method for producing a fermented pellet according to any one of claims 1 to 5, wherein the fermentation is carried out for 14 to 20 days.   The method for producing a fermented pellet according to any one of claims 1 to 6, wherein the sewage sludge residue pellet is obtained by pelletizing a low molecular weight treated sewage sludge residue.   The method for producing a fermented pellet according to any one of claims 3 to 7, wherein the center part excluding the top part and the lower part of the piled bacteria-supporting sewage sludge residue pellet is covered with a covering material and fermented.   The method for producing a fermented pellet according to any one of claims 1 to 8, wherein the produced fermented pellet is compost.   A pellet-fermenting method comprising: carrying Bacillus bacteria on the inside of the pellet and fermenting the bacteria-carrying pellets on which the lactic acid bacteria are carried on the surface layer in piles.

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