JP4947673B2 - Planted cultivation soil and its manufacturing method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a planted cultivation soil that is produced using clean water sludge and sewage sludge and a method for producing the same.

  As of 2009, the annual generation amount of water sludge has reached about 360,000 DS-t (DS-t: tonnage of concentrated sludge solids). However, the effective utilization rate of drinking water sludge in the entire water supply is only 31.3% in 2000 and 36.1% in 2001, and the resource recovery rate is still low. Landfill disposal is the most common disposal method for generated water sludge. However, in the vicinity of large cities that have various problems in securing disposal sites and transportation, effective utilization of generated sludge is important. Many studies have been made.

  As one of them, the recycling of horticultural soil, ground construction materials, construction materials (roadbed materials, pipe laying materials, landfill materials, etc.), cement materials, etc. are being studied. In particular, in recent years it has become more difficult to secure a final disposal site for industrial waste, and the importance of environmental conservation has become increasingly important. Efforts for recycling are required.

  Currently, the most widely used water treatment system in Japan is the rapid filtration system. It consists of five processes: sand settling, agglomeration, settling, filtration and disinfection, with the main functions being removal of components larger than colloidal particles and recent detoxification. In recent years, the introduction of advanced water treatment that combines biological treatment, activated carbon treatment, ozone treatment, and the like for the purpose of removing off-flavor-causing components has been spreading. In these processes, a flocculant is added to agglomerate and precipitate fine particles contained in the raw water. The most widely used flocculant is the sulfate band (aluminum sulfate). Further, polymagnesium chloride and polyferric chloride are also used as the inorganic polymer system. Therefore, the main components of the water sludge are organic matter, aluminum oxide, silica, iron oxide, microorganisms and the like. That is, the water sludge is rich in aluminum oxide, silica, iron oxide, and the like, which are basic components of soil clay minerals. In particular, the silica content required for the synthesis of plant tissues is high. In recent years, silica has been found to play an important function in plant physiology, and is an element added to essential plant elements.

  When composting such sewage sludge, it is effective to mix it with a raw material containing a large amount of organic matter such as sewage sludge and wood waste and to complete the fermentation. However, this ripening treatment requires a considerable amount of time. Therefore, search for beneficial microorganisms that ferment compost raw materials in a short period of time has been attempted.

  For example, those described in Patent Documents 1 to 6 are known as microorganisms that efficiently decompose organic waste, in particular, organic sludge.

  Patent Document 1 discloses a microorganism belonging to the genus Bacillus and having the ability to decompose sludge under alkaline conditions. Patent Document 2 discloses a microorganism belonging to Bacillus subtilis that decomposes proteins contained in organic sludge and biological sludge. Patent Document 3 discloses a microorganism belonging to the genus Pseudomonas that has the ability to decompose and extinguish organic matter in organic waste and sewage sludge. Patent Document 4 discloses a microorganism belonging to the genus Rhodobacter that is useful for environmental purification such as wastewater treatment. Patent Document 5 discloses a microorganism belonging to the genus Bacillus useful for the treatment of organic solids. Patent Document 6 discloses a gram-positive microorganism belonging to the genus Brevibacillus, which produces a proteolytic enzyme and has an ability to decompose organic sludge. Non-Patent Document 1 proposes a technique for reducing excess sludge using a thermophilic bacterium of the genus Bacillus.

JP 2000-139449 A JP 2002-125657 A JP 2003-235547 A JP 2003-245066 A JP 2004-267127 A JP 2006-230332 A

Susumu Hasegawa: Sludge reduction and prevention technology, 248-270, NTS, 2000. E. Pikuta, A. Lysenko, N. Chuvilskaya, U. Mendrock, H. Hippe, N. Suzina, D. Nikitin, G. Osipov, K. Laurinavichius: Anoxybacillus pushchinensis gen. Nov., Sp. Nov., A novel anaerobic alkaliphilic, moderately thermophilic bacterium from manure, and description and Anoxybacillus flavithermus comb.nov., International Journal of Systematic and Evolutionary Microbiology, 50, 2109-2117, 2000. A. Derekova, C. Sjoholm, R. Mandreva, M. Kambourova: Anoxybacillus rupiensis sp. Nov., A novel thermophilic bacterium isolated form Rupi basin (Bulgaria), Extremophiles, 11, 577-583, 2007. L. Feng, W. Wang, J. Cheng, Y. Ren, G. Zhao, C. Gao, Y. Tang, X. Liu, W. Han, X. Peng, R. Liu, L. Wang: Genome and proteome of long-chain alkane degrading Geobacillus thermodenitrians NG80-2 Isolates from a deep-subsurface oil reservoir, Proceedings of the National Academy of Science USA, 104, 5602-5607, 2007. M. Mesbah, U. Premachandran, W. B. Whitman: Precise measurement of the G + C content of deoxyribonucleic acid by high-performance liquid chromatography, International Journal of Systematic Bacteriology, 39, 159-167, 1989. Y. Okamura, N. Inoue, T. Nikai: Isolation and characterization of a novel acid proteinase, tropiase from Candida tropicalis IFO 0589, Japanese Journal of Medical Mycology, 48, 19-25, 2007. K. J. Raser, A. Posner, K. K. W. Wang: Casein zymography: A method to study μ-calpain, M-calpain, and their inhibitory agents, Archives of Biochemistry and Biophysics, 319, 211-216, 1995. Shinjiro Kanazawa: Soil Enzyme Measurement Method, Global Environment Survey and Measurement Dictionary-Volume 1, Land Area, pp.1111-1114, Fuji Techno System, Tokyo, 2002. J. N. Ladd: Properties of proteolytic enzymes extracted from soil, Soil Biology and. Biochemistry, 4, 337-237, 1971.

  However, the above-mentioned microorganisms that decompose organic sludge are not practically used industrially.

  Accordingly, an object of the present invention is to provide a highly functional planting soil that can be fully matured in a short period of time by using the water sludge in order to recycle the water sludge and a method for producing the same. It is in.

  As a result of searching for microorganisms that efficiently decompose organic sludge, the present inventor has developed a new bacterial species (high protease activity) of Anoxybacillus genus bacteria (see Non-Patent Documents 2 and 3) that dissolves excess sewage sludge. Was isolated and identified from excess sewage sludge and named Anoxybacillus sp. MS8 strain. Moreover, it discovered that an organic waste can be decomposed | disassembled in a short time by using the thermophilic cellulose degrading bacterium Geobacillus thermodenitrificans NG80-2 strain (refer nonpatent literature 4) isolated and identified from the bark compost. This fungus, which has a high ability to dissolve excess sludge that is remarkably rich in readily decomposable organics at high temperatures, is most suitable for compost production. This is because the purpose of composting is to quickly decompose these easily decomposable organic substances into stable organic substances.

  Therefore, compost using excess sewage sludge and pruned branch chips (woody waste) using these thermophilic sludge-dissolving bacteria Anoxybacillus sp. MS8 (high protease activity) and thermophilic cellulose-degrading bacteria Geobacillus thermodenitrificans NG80-2 as inoculums. I tried to build a new technology. The concept is to build a low-cost composting facility that can produce profit quickly and reduce the fermentation period.

  The present inventor is a microorganism that dissolves sludge from surplus sludge conditioned at 60 ° C for the purpose of developing high-value-added planting fertilizer (compost) using sewage surplus sludge and pruned branch chips (wood waste). Were screened. Using conditioned sewage sludge as a sample, it was applied to a medium in which sterilized sludge was suspended, and those in which halo was observed around colonies of the grown bacteria were separated. The isolated bacterium is a Gram-positive gonococcus and is a bacterium belonging to the genus Anoxybacillus (see Non-patent Documents 2 and 3) as a result of biochemical / physiological tests on the strain and DNA homology analysis of the 16S ribosomal RNA gene. It has been found. There is no report that bacteria belonging to the genus Anoxybacillus solubilize sewage sludge, but the existence of a thermophilic bacterial strain of the genus Bacillus that can dissolve sludge is known (see Non-Patent Document 4).

  The bacterial strain isolated and identified by the inventors this time dissolves sewage sludge at a temperature of 50 to 60 ° C. Biochemical / physiological testing for this strain identified 100% of Geoibacillus stearothermophilus and 98.0% of Bacillus lentus. Furthermore, in the DNA homology analysis of 16S ribosomal RNA gene, it was determined to be Anoxybacillus beppuensis with a probability of 96.8% and Anoxybacillus rupiensis with a probability of 96.6%. From these results, since this strain was judged to be a new strain of bacteria belonging to the genus Anoxybacillus, this bacterial strain was named Anoxybacillus sp. MS8 strain.

  The present invention is based on these findings.

That is, the planting culture soil according to the present invention is a mixture of sewage sludge compost composed of a raw material mixture obtained by mixing sewage sludge and wood waste, and water sewage sludge obtained as a sediment in a settling pond of a water purification plant , The mixture is fermented with Anoxybacillus sp. (Anoxybacillus) MS8 strain (Accession No. FERM P-21818) .

In addition, in the method for producing plant culture nourishment according to the present invention, a raw material mixture obtained by mixing sewage sludge and wood waste is fermented by Anoxybacillus sp. MS8 strain (accession number FERM P-21818). A first step of producing sludge compost;
A second step of producing an intermediate mixture by mixing the sewage sludge compost and the water sewage sludge obtained as a sediment of a settling basin of a water purification plant ;
And a third step of fermenting the intermediate mixture again with the Anoxybacillus sp. (Anoxybacillus) MS8 strain to produce plant culture soil.

  This makes it possible to effectively use sewage sludge and clean water sludge as compost resources, and in particular, fermenting using Anoxybacillus sp. it can. Moreover, by using both sewage sludge and clean water sludge as raw materials, it is possible to compensate for the lack of fertilizer components in each of them, and to obtain plant culture nourishment with high functionality as a fertilizer.

  Furthermore, a lightweight material can also be mixed in the above-mentioned planting culture soil.

  Thereby, the planting culture soil is reduced in weight and can be used for rooftop greening. Moreover, lightness and water retention are improved, and the functionality as culture soil can be enhanced.

  Here, the “lightweight material” refers to a granular porous lightening material that has been reduced in weight by providing a large number of microscopic voids therein. Specifically, as the lightweight material, for example, crushed foamed glass or Perlite etc. can be used. In particular, foamed glass is manufactured by recycling waste such as bottles, so by using foamed glass as a lightweight material, waste can be used effectively, and planting and cultivation soil should be provided in consideration of the global environment. Can do.

In addition, “sewage sludge” refers to sludge obtained as a sediment that separates from sewage in a sewage treatment plant, and “sewage sludge” refers to sludge obtained as a sediment in a sedimentation basin of a water purification plant. . “Wood waste” refers to woody waste such as pruned branches, bark, and sawdust. The “sewage sludge compost” may be a raw material mixture itself obtained by mixing sewage sludge and wood waste, or may be obtained by fermenting and dissolving this raw material mixture.

  Moreover, in the said 2nd process, the said sewage sludge compost 2 volume part or more and 5 volume part or less and the said sewage sludge 8 volume part or less 5 volume part or more may be mixed in the ratio used as a total of 10 volume parts. it can.

  As a result, while ensuring the amount of nitrogen, phosphoric acid, and potassium contained in the planted cultivation soil to be produced as a fertilizer, mineral components such as aluminum oxide, silica, and iron oxide contained in the water sludge are also included. It can be secured sufficiently.

  In the third step, the intermediate mixture can be fermented in an aerobic state.

  Moreover, in the said 1st process, fermentation of the said raw material mixture can also be performed in an aerobic state.

  Here, the “aerobic state” refers to a state in which free oxygen molecules that can be used by living organisms exist.

  As described above, according to the present invention, by using Anoxybacillus sp. MS8 strain, a raw material mixture in which wood waste is mixed with sewage sludge and water sewage sludge is matured in a short period of time. Therefore, sewage sludge and clean water sludge can be effectively used as compost resources. In particular, since the period until the raw material mixture is fully matured can be shortened, the equipment for fermentation and storage can be reduced, and the cost of the planted cultivation soil to be produced can be reduced.

DNA base sequence of 16S ribosomal RNA gene of Anoxybacillus sp. MS8 strain (primer: 1094f-r1L-r2L-r3L) It is a figure showing the manufacturing plant of the planting cultivation soil which concerns on Example 1 of this invention. It is a figure showing the manufacturing process and fermentation temperature of the planting cultivation soil which concern on Example 1 of this invention. It is a figure showing the time-dependent change accompanying fermentation of total bacteria and the number of living bacteria. It is a figure explaining the structure and usage of the KS type seedling cultivation container (kit) for germination index.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(1) Novel microorganisms to be used First, the Anoxybacillus sp. (Anoxybacillus) MS8 strain (accession number FERM P-21818), which is a bacterium used for fermentation of raw materials for planting culture soil in the present invention, will be described in detail.

[Separation and identification of bacteria]
Take 240 g of excess sewage sludge in a 500 ml flask, shake and culture it at 60 ° C and 60 rpm for 1 week, mix the culture solution with the newly collected excess sludge so that the weight ratio is 1: 2. Cultured continuously. This operation was repeated once a week (4 consecutive cultures). The culture broth was diluted, applied to a flat agar medium in which sterilized surplus sludge was suspended, and cultured at 60 ° C. Then, what can be confirmed halo was isolated around the colony.

  Isolated bacterial strains were examined for morphological and biochemical / physiological properties. This fungus can grow at temperatures between 50 ° C and 65 ° C, pH 6.0 to 8.0, and biochemical / physiological such as Gram and spore staining, catalase test, oxidase test, OF test and API50CHB (Biomerieux, France) As a result of a physical test (see Table 1), it was found that the aerobic spore-forming bacterium has a high homology (100%) with the Gram-positive gonococcus Geoibacillus stearothermophilus.

  Next, we analyzed the DNA homology of the 16S ribosomal RNA gene, which is used as the most effective molecular marker for the study of microbial evolutionary strains. The 16S ribosomal RNA gene of this strain was amplified by PCR under the following conditions (f1L forward primer: 5'-gagtttgatcctggctcag-3, r4L reverse primer: 5'-acgggc ggtgtgtgtacaag-3, reaction conditions: (1) 5 ° C at 5 ° C (2) 95 ° C for 30 seconds, (3) 52 ° C for 30 seconds, (4) 68 ° C for 1 minute 30 seconds, (2) to (4) 30 cycles, (5) 68 ° C The PCR product was excised from the PCR product by agarose gel electrophoresis and purified with QIAquick Gel Extraction Kit (QIAGEN Sciences, USA). Then, the purified DNA fragment and sequencing primer (63f forward primer: 5'-caggcctaacacatgcaagtc-3 ', 1094f primer: 5'-gtcccgcaacgagcgcaac-3', r1L reverse primer: 5'-gtatta ccgcggctgctgg-3 ', r2L primer: 5'-catcgtttacggcgtggac-3 ', r3L primer: 5'-ttgcgctcgttgcgggact-3' or 1387r primer: 5'-gggcggtgtgtacaaggc-3 ') (1) 96 ° C for 20 seconds, (2) 50 ° C For 20 seconds, (3) 60 ° C for 4 minutes, (1) to (3) 30 times), and DNA sequencer CEQ8000 (Beckman Coulter, USA). The DNA base sequence of the RNA gene was obtained (FIG. 1, attachment). Based on the obtained base sequence of 1,291 bases, sequence matching was performed with BLAST and FASTA (http://www.ddbj.nig.ac.jp/) which are typical DNA homology search engines. As shown in Table 2, the homology with Anoxybacillus beppuensis and Anoxybacillus rupiensis was the highest. Furthermore, when the DNA base composition of Anoxybacillus sp. MS8 strain was quantified by HPLC method (Non-patent Document 5) (YMC pack AQ-312 column (YMC Co., Ltd.)), the G + C content was 53.2%.

  Since this strain is identified by biochemical / physiological tests, the DNA homology of the 16S ribosomal RNA gene is 97% or less, and dissolves sewage sludge as shown in Example 2, the genus Anoxybacillus Since it is judged to be a new bacterial species of bacteria (related to Anoxybacillus beppuensis), this bacterium was named Anoxybacillus sp. MS8 strain (Accession No. FERM P-21818).

(2) Composting facility Next, the facility used for producing the planted cultivation soil according to Example 1 of the present invention will be briefly described. FIG. 2 is a diagram illustrating a planting cultivation soil production plant according to Example 1 of the present invention. The planting cultivation soil production plant includes a fermenter 1, a deodorizing device 2, a sludge hopper 3a, an auxiliary material hopper 4, an inoculum hopper 5, a mixer 6, conveyors 7 and 8, a fermenter blower 9, and an automatic bagging machine. 10 is provided.

  The sewage sludge and the sewage sludge, which are the raw materials of the planting culture soil of the present invention, are respectively charged into the sewage sludge hopper 3a and the sewage sludge hopper 3b. Further, the wood waste as the secondary material is put into the secondary material hopper 4. In addition, Anoxybacillus sp. (Anoxybacillus) MS8 strain (accession number FERM P-21818), which is a bacterium used for fermentation of the raw material mixture, is introduced into the inoculum hopper 5 together with medium materials (mud, bark compost, etc.).

  The raw materials charged into the sewage sludge hopper 3a, the clean water sludge hopper 3b, the auxiliary material hopper 4 and the inoculum hopper 5 are conveyed and charged into the mixer 6 by the conveyor 7, and the mixer 6 mixes these raw materials. The mixer 6 is a cylindrical continuous rotary mixer.

  The mixed raw material is conveyed to the fermenter 1 by the conveyor 8. The fermenter 1 is an open-type fermenter and is partitioned into a plurality of partial tanks by a partition wall, and can be managed separately for each stage of fermentation of the raw material. The gas generated by fermentation of the raw material in the fermenter 1 is recovered by the deodorizer 2 and deodorized. Furthermore, the raw material in the fermenter 1 is supplied with air by a fermenter blower 9.

  When the raw material is finally ripe, it is transported to the automatic bagging machine 10 by a shovel car, packed in a bag and shipped.

(3) Manufacturing process of planting culture soil FIG. 3 is a diagram showing the manufacturing process and fermentation temperature of planting culture soil according to Example 1 of the present invention. Fig.3 (a) shows the result of having measured fermentation temperature in each process in manufacture of planting culture soil, FIG.3 (b) has shown the content and period of each process in manufacture of plantation culture soil.

(Process 1)
First, with the mixer 6, it mixes with sewage sludge and Anoxybacillus sp. (Anoxybacillus) MS8 stock | strain which is an inoculum. Furthermore, the raw water sludge which is a raw material is added to the mixer 6 and mixed to produce a raw material mixture. The manufactured raw material mixture is conveyed to the fermenter 1 by the conveyor 8.

  In the production of the raw material mixture, “sewage sludge compost” can be used as a raw material instead of “sewage sludge”. Sewage sludge compost is compost produced by mixing sewage sludge and wood waste (pruned branches, bark, etc.) with a mixer 6 and fermenting them in the fermenter 1.

  The mixing ratio of the sewage sludge (or sewage sludge compost) and the sewage sludge is 8 parts by volume or less and 5 parts by volume or more of the sewage sludge compost with respect to 2 parts by volume or more and 5 parts by volume or less. Mix in the ratio When the ratio of sewage sludge compost is less than 2 parts by volume, the activity of Anoxybacillus sp. MS8 strain becomes dull and the fermentation time tends to be longer. In addition, the amount of nitrogen, phosphoric acid, and potassium, which are plant tri-nutrients, is remarkably small compared with sewage sludge. This is because the amount of nitrogen, phosphoric acid and potassium contained in the originally taken water is small because the water used for clean water is taken from as clean a water source as possible. Therefore, when it becomes less than 2 volume parts of sewage sludge compost, the quantity of these three nutrients will run short and the quality as compost will fall. Moreover, when the ratio of sewage sludge compost is more than 5 parts by volume, the amount of water sludge that can be treated decreases, and mineral components such as aluminum oxide, silica, and iron oxide contained in the water sludge decrease. In the manufactured compost, the content ratio of these components decreases.

(Process 2)
In the fermenter 1, primary fermentation of the raw material mixture is performed. The primary fermentation is performed for a period of about 17 days. During this time, as shown in FIG. 3, the temperature of the raw material mixture rises from the initial normal temperature state to about 80 to 90 ° C. (in the actual measurement, the maximum temperature is 85.2 ° C.). In addition, the fermentation temperature shown in FIG. 3 measured the temperature of the site | part of about 70 cm depth in five points of the upper part of a fermentation deposit, and took the average.

(Process 3)
The raw material mixture subjected to primary fermentation in the step 2 is turned back (first turn back). Then, secondary fermentation is performed over a period of about 19 days. During this time, the temperature of the raw material mixture is maintained at about 80 ° C. (as measured, the maximum temperature is 82.7 ° C.) as shown in FIG. 3 by fermentation.

(Process 4)
The raw material mixture subjected to secondary fermentation in step 3 is turned back (second turn). Then, the tertiary fermentation is performed over a period of about 14 days. During this time, the temperature of the raw material mixture is maintained at about 65 ° C. (as measured, the maximum temperature is 66.4 ° C.) as shown in FIG. 3 by fermentation.

(Process 5)
The raw material mixture subjected to the tertiary fermentation in the step 4 is turned back (third turn). Then, quaternary fermentation is performed over a period of about 16 days. During this time, the temperature of the raw material mixture is maintained at about 55 ° C. (maximum temperature 52.9 ° C. in actual measurement) as shown in FIG. 3 by fermentation.

(Step 6)
The raw material mixture subjected to quaternary fermentation in step 5 is turned back (fourth turn). Then, quintic fermentation is performed over a period of about 5 days. During this time, the temperature of the raw material mixture is maintained at about 45 ° C. (as measured, the maximum temperature is 46.5 ° C.) as shown in FIG. 3 by fermentation.

(Step 7)
Since the mixture fertilized in the fifth step in step 6 is a fully cultivated planting soil, it is packed into a compost bag by the automatic bagging machine 10. As described above, the planted cultivation soil according to Example 1 is manufactured. The production days were about 80 days. This number of days is shorter than the number of days for manufacturing conventional waste water sludge compost. Looking at the temperature course of the fermentation temperature, the temperature rises in a short period due to the mixed deposition, and reaches a high temperature of 85.2 ° C. already in the primary fermentation. Thereafter, the temperature gradually decreased as the ripening progressed, but in actual measurement, a high temperature of about 80 ° C. or higher was maintained until the secondary fermentation was completed. Moreover, it was 46.0 degreeC also in the stage of the final quintic fermentation. Therefore, the planting cultivation soil of this example was extremely excellent in that the product temperature rose to 80 ° C. or more over about one month.

  In the above-described embodiment, the reversal is performed five times. However, since the maturation is almost completed by the third reversal as described later, the fourth and fifth reversal may be omitted.

  In addition, after the said (process 7), you may mix a lightweight material as an additional material in the planting cultivation soil manufactured by the said each process. Thereby, it becomes possible to utilize the planting cultivation soil manufactured as rooftop greening material.

  Rooftop greening has various effects such as improving urban environment such as heat island countermeasures, economic effects due to energy savings, and creating a space of comfort, such as physiological and psychological effects on people. Is expected. Because of the problem of the load applied to the building due to the rooftop greening, and the rooftop is in a dry environment, the soil used for rooftop greening is required to be lightweight, water permeable, breathable, water retentive, and the like.

In order to satisfy these demands, lightweight materials, that is, porous lightweight materials such as baked waste glass (foamed glass) are mixed into the planted cultivation soil produced by the above-mentioned processes, thereby reducing the weight.・ It has become clear that water retention and the like are further improved. If the waste glass fired product (foamed glass) is used, the raw materials for planting and cultivation soil produced are all industrial waste. That is, the lightened planting and cultivation soil becomes a base soil excellent in environmental conservation, and in addition, becomes a carbon neutral product that does not generate global warming gas CO ₂ .

(4) Physicochemical characteristics of planted soil for cultivation Next, the results of investigation on the physicochemical properties of the planted soil for cultivation of the present invention will be described in detail.
As the raw water sludge, the water sludge generated as a mechanical dewatered cake at the Anasei water purification plant in Kitakyushu City was used. The chemical components are as shown in (Table 3). Therefore, the present water sludge is a material mainly composed of aluminum oxide and silicic acid and then rich in iron oxide components.

  (Table 4) is the result of investigating the physicochemical properties of the raw materials and seed compost for the mixed planting soil cultivation of water and sludge used as raw materials. Here, “sewage sludge compost” in this example is compost obtained by fermenting a mixture of sewage sludge and wood waste such as bark compost. In this embodiment, bark is used as “wood waste”.

  (Table 5) is the result of investigating the time-dependent change of the water content and chemical composition in the fusion planting soil culture household of the sewage sludge and the sewage sludge used as raw materials.

  The water content of the raw material was 73.3 wt%, but the mixture was 68.0 wt%, the first turnover was 65.5 wt%, the second turnover was 64.3 wt%, the third turnover 62.5 wt%, 61.3 wt% at the fourth turnover, and 60.1 wt% at the fifth turnover (final product).

The change in pH value is as shown in (Table 5). As shown in (Table 4), the water sludge has a pH (H ₂ O) of 6.94 and is almost neutral, but the pH of the sewage sludge compost is 6.41, which is weakly acidic. In the second turn-over, the pH (H ₂ O) is 6.68, which is slightly acidic. The pH value hardly changed during the fermentation process, indicating a slight acidity.

  The total carbon content of the water sludge and sewage sludge compost was 13.7 wt% and 34.8 wt%, respectively. In addition, the total carbon content of the raw material mixture obtained by mixing them was 22.8 wt%, and 22.0 wt% at the first turnover. The total carbon content clearly decreased with the progress of fermentation, and decreased to 19.4 wt% at the fifth round-back (final product) of the final fermentation.

  The total nitrogen contents of the water sludge and sewage sludge compost were 1.96 wt% and 3.13 wt%, respectively. Since the total amount of nitrogen in the sewage sludge compost was large, the total amount of nitrogen in the mixture was 2.27 wt%. The total amount of nitrogen gradually increased as the fermentation progressed, and increased to 2.63 wt% at the fifth turnover (final product) of the final fermentation.

  The C / N ratios of clean water sludge and sewage sludge compost were 7.0 and 11.1, respectively. Moreover, in these mixtures, it was 10.04. Since the total nitrogen amount increased and the total carbon amount decreased with the progress of fermentation, the C / N ratio gradually decreased with the progress of fermentation reflecting this. It decreased to 7.3 at the 5th turnover (final product) at the end of fermentation.

  The amounts of potassium in the sewage sludge and sewage sludge compost were 0.133 wt% and 1.10 wt%, respectively. It was shown that the amount of potassium in the sewage sludge was significantly lower than the amount of potassium in the sewage sludge compost. The amount of potassium clearly increased as the fermentation progressed, and increased to 0.775 wt% at the fifth round-off (final product) of the final fermentation.

  Magnesium content of the sewage sludge compost and the sewage sludge compost was 0.308 wt% and 0.660 wt%, respectively. As for the amount of magnesium, the amount of sewage sludge compost was about twice as large as that of clean water sludge, and no extreme difference was observed between the two. The magnesium content of these mixtures was 0.517 wt%. The amount of magnesium clearly increased with the progress of fermentation, and increased to 0.670 wt% at the fifth round-back (final product) of the final fermentation.

  The amounts of calcium in the sewage sludge compost and sewage sludge compost were 0.981 wt% and 3.600 wt%, respectively. It was shown that the amount of calcium in the sewage sludge was significantly lower than the amount of calcium in the sewage sludge compost. The calcium content of these mixtures was 2.181 wt%. The amount of calcium clearly increased as the fermentation progressed, and increased to 2.998 wt% at the fifth round-back (final product) of the final fermentation.

  The amounts of phosphoric acid in the water sludge and sewage sludge compost were 1.102 wt% and 2.370 wt%, respectively. It was shown that the amount of phosphoric acid in the sewage sludge was significantly lower than the amount of phosphoric acid in the sewage sludge compost. The phosphoric acid content of these mixtures was 1.702 wt%. The amount of phosphoric acid clearly increased with the progress of fermentation, and increased to 2.299 wt% at the fifth round-back (final product) of the final fermentation.

  The EC (electrical conductivity) of the water sludge and sewage sludge compost was 1.29 ms / cm and 3.95 ms / cm, respectively. The EC of clean water sludge was shown to be significantly lower than that of sewage sludge compost. The EC of these mixtures was 3.22 ms / cm. The EC increased clearly with the progress of the fermentation and increased to 7.29 ms / cm at the fifth round-off (final product) of the final fermentation.

  As mentioned above, the water sludge used in this survey showed neutrality. However, since the sewage sludge compost, which is a secondary material, is slightly acidic, the pH value of these mixed materials showed slightly acidic. The pH value decreased to some extent during the fermentation process, and no significant fluctuation was observed until the final product.

  Moreover, as can be seen from Table 4, the amount of nitrogen and phosphoric acid in the three nutrients (fertilizer components) of the plant is significantly less than that of the sewage sludge. Therefore, by using sewage sludge compost having a large amount of nitrogen as an auxiliary material, the amount of nitrogen in the planted cultivation soil after the fifth turnover after fermentation was completed could be increased to 2.63 wt%. In addition, the C / N ratio was a very low value of 7.38. Therefore, it can be said that the planting culture soil of this example was finished into a high quality planting culture soil with a large amount of nitrogen and a low C / N ratio.

  Moreover, by using sewage sludge compost having a large amount of potassium as an auxiliary material for clean water sludge having a small amount of potassium, the amount of potassium in the compost could be remarkably increased from 0.133 wt% to 0.775 wt%. Similarly, it was also shown that the amount of calcium was improved from 0.981 wt% to 2.998 wt% by mixing sewage sludge compost with a large amount of calcium with water sludge with a small amount of calcium.

  The amount of water sludge with a small amount of phosphoric acid increased from 0.102 wt% to 2.299 wt% by mixing with sewage sludge compost with a large amount of phosphoric acid. As a result, a satisfactory amount of phosphoric acid could be secured as planting soil. In addition, the amount of magnesium, which is an essential element for chlorophyll synthesis, was found to be abundant at 0.67 wt% in the final product.

  In addition, this time, the sewage sludge was an organic material whose EC was significantly smaller than the sewage sludge. By mixing sewage sludge compost with high EC as a secondary material, EC increased to 3.22. And by progress of fermentation, it increased to 7.29 in the 5th turnover (final product).

(5) Bacteria and Escherichia coli counts in plantation and cultivation soil Next, the results of investigation of bacteria and coliform counts in plantation and cultivation soil obtained as a final product are shown. In compost, the number of bacteria obtained by the culture method (agar medium) can be measured only 1% or less of the total number of living bacteria. Therefore, the number of bacteria in the fermentation process was measured by direct microscopy. (Table 6) shows the number of bacteria and the number of E. coli by the culture method of the final product.

  In the measurement of the number of bacteria by direct microscopic method, the total number of bacteria was fluorescent dye ethidium bromide (EB), and the number of living bacteria was fluorescent dye 6-carboxy fliorescein diacetate (CFDA). FIG. 4 shows changes with time in the fermentation of the total bacteria and viable bacteria counts stained with these fluorescent dyes.

The total number of bacteria in the raw water sludge (EB staining) by the direct microscopic method is 1.1 × 10 ¹⁰ per 1 g of dry matter, and there are about 11 billion bacteria. The total number of live bacteria (CFDA staining) was 3.1 × 10 ⁹ , and about 3.1 billion live bacteria were present. On the other hand, the total number of bacteria in the sewage sludge compost is 6.35 × 10 ₁₀ , there are about 63.5 billion bacteria, the total number of live bacteria is 5.21 × 10 ⁹ , and about 5.2 billion live bacteria Existed. Thus, it was revealed that the sewage sludge compost contains 6 times as many bacteria as the total number of bacteria and 2 times as many bacteria as the sewage sludge.

  Therefore, it was shown that the sewage sludge compost has significantly more bacteria than the clean water sludge. Reflecting this, the mixture of both resulted in about 2.5 cultures of total bacteria and about 1.7 times more total live bacteria.

  In the number of bacteria in the fermentation process, the total number of bacteria showed an increase due to the initial fermentation at the first turnover, and there were 35 billion bacteria, and at the second turnover, there were 32 billion bacteria. However, the number of bacteria decreased at the 3rd reversal and did not show any significant fluctuations after that. However, the total number of live bacteria tended to increase, and the 3rd reversal was the most, about 9.1 billion. Viable bacteria were observed.

Moreover, as shown in (Table 6), the total number of bacteria in the final product by the culture method was 23.5 × 10 ⁷ per 1 g of dry matter, and about 240 million were present.

  The number of E. coli in the final product was below the detection limit and could not be detected.

  As described above, the planting culture soil in this example showed a surprising number of bacteria, with the total number of bacteria reaching about 26 billion during the fermentation process. The microbial cell has a function as a pool of plant nutrients. Therefore, the planting culture soil in this example is determined to be a high quality bio plantation culture soil rich in microbial biomass. The total number of bacteria includes dead bacteria that have no activity. When only live bacteria were examined by CFDA staining, there were about 8.6 billion live bacteria, and the total live bacteria accounted for 32.3%.

  When the total number of bacteria counted by the direct microscopic method and the culture method was compared, the total number of bacteria counted by the direct microscopic method was 366 times higher. Therefore, it is shown that the culture method using an agar medium can count only 0.27% of the total bacteria present in the plant culture soil of the final product. That is, 99.8% of the bacteria present in the planted cultivation soil of the final product cannot be cultured on the agar medium and cannot be counted using the agar medium.

(6) Evaluation of the degree of maturity of planted cultivation soil by the germination index method Whether or not the produced planted cultivation soil of the present invention is a so-called good ripe organic fertilizer (compost) that does not inhibit plant growth is extremely high. is important. Therefore, the degree of maturity was determined by the newly improved germination index method for the planted cultivation soil of the present invention shown in this example.

  FIG. 5 shows an outline of a newly developed germination index kit (see Japanese Patent Application Laid-Open No. 2004-151586). The growth measuring instrument A includes a cultivation tank 10, a landing member 20, a growth holder 25, a support substrate 30, and a lid body 40.

  The cultivation tank 10 is opened upward and is made of a transparent or translucent member such as an acrylic resin. A partition wall body 12 is erected on the inner bottom portion 11 of the cultivation tank 10 in the longitudinal direction, and the cultivation tank is divided into two in the longitudinal direction by the partition wall body 12. Moreover, the scale parts 13a and 14a which measure the growth degree of a plant are provided in the outer surface parts 13 and 14 on the front side and the back side of the cultivation tank 10 with a lower end part of the growth holder 21 as a reference point 15 at an interval of 1 cm. It has been.

  The landing member 20 is a member for planting, germinating, and growing plant seeds, and is accommodated in the cultivation tank 10. The landing member 20 is made of a material that can absorb moisture, an extract from a composted product, a fertilizer-containing aqueous solution, and the like, and can be used for plant seeding, germination, and growth. It is composed of absorbent cotton, sponge, filter paper, rock wool, glass wool, ceramic porous body, coconut shell mat and the like.

  The growth holder 25 is accommodated in the cultivation tank 10 in a state in which a plurality of growth holders 25 are arranged in parallel to the support substrate 30. The growth holder 25 is made of a transparent or translucent vertically long cylindrical body having visibility, and a plant sprouted from the landing member 20 can be visually recognized. The support substrate 30 is composed of a dark member, which is a black resin plate in this embodiment, so that the degree of growth of plants growing in the growth holder 25 having visibility can be easily seen. In FIG. 5, 15 growth holders 25 are connected in parallel to the support substrate 30, and are surrounded by the support substrate 30, the side substrates 32 and 32, and the front substrate 33 to form a unit. In addition, at the lower part of each growth holder 25, the lower end portion of each growth holder 25 and the lower end portion of the side substrate 32 are set to have the same length so that the landing member 20 can be accommodated. The lower end portions of 30 and the front substrate 33 are set shorter than the lower end portions of the growth holders 25 and the lower end portions of the side substrate 32.

  The lid 40 is a lid that closes the upper opening of the cultivation tank 10 and is made of a transparent or translucent material such as acrylic resin. The lid 40 is covered and the inside of each growth holder 25 is clouded with water vapor during seed germination and growth. Therefore, in order to prevent fogging and the like, a ventilation hole having a diameter of 3 mm is provided at the center in the longitudinal direction. 41 are formed at three positions at equal intervals.

  When the planted cultivation soil of the manufactured final product is applied to the farmland, it must be determined whether the planted cultivation soil is sufficiently matured. Therefore, a simple and quick germination index method that incorporates the advantages of the seedling test method and pot cultivation test method was improved. In this method, Komatsuna is cultivated with the extract of planting soil with distilled water as a control, the germination rate and stem length are examined on the 7th day, and the germination index is obtained using the following formula.

  Specifically, first, 180 mL of boiled distilled water was added to 20 g of a dried fine powder sample, stirred well, and then allowed to stand for 1 hour. After standing, centrifugation was performed at 7000 rpm for 10 minutes. After centrifugation, the supernatant was added to the landing member 20 of the plant growth measuring instrument developed by the present inventors (see FIG. 5), and 30 Komatsuna seeds were sown. Cultivated in a constant temperature bath at 25 ° C for one week. The control was cultivated with distilled water after the same treatment. One week later, the number of germination and the length of the stem were measured, and the germination index (GI) was measured by the above formula (1).

  If the germination index is 100% or more, that is, if the stem length of the plant grown with the compost extract is longer than that grown with distilled water, the degree of maturity is sufficient because the plant growth is not hindered .

(result)
The results of the germination index are shown in (Table 7). The germination index of clean water sludge was 120%, with Komatsuna growing well. On the other hand, the germination index of sewage sludge compost as an auxiliary material was 146% and was a fully matured compost. The germination index of the mixture of both was 136%, but the germination index after the first reversal increased significantly to 167%. Thereafter, the germination index increased with the progress of fermentation, and showed 204% in the final product after the final fifth turnover.

  The results of the germination index as described above indicate that the plant culture soil of the present invention contains almost no substances that inhibit plant growth. On the other hand, the sewage sludge compost used as an auxiliary material indicates that the inhibitor is completely decomposed and is a fully-ripe bio-organic fertilizer that allows plants to grow well. When both were mixed and passed through the fermentation process (primary fermentation), the germination index increased markedly. Furthermore, since the germination index increases with the progress of fermentation, it shows that the plant growth inhibitory substance derived from the water sludge that inhibits the growth of the plant by the heat of fermentation is decomposed.

  Looking at the results of the germination index of the fermentation process, it has been shown that the second turnover has already become a very good fully ripe bioplant cultivation soil with a germination index of 190%. Then, considering that the increase in the numerical value during the fermentation process is slight, it suggests that most of the fermentation has already been completed in the second round of tertiary fermentation.

  Therefore, it was clarified that composting of sewage sludge is finished to a very good ripe bioplant cultivation soil by the second turnover (tertiary fermentation) by using sewage sludge compost as an auxiliary material. . In other words, it means that it is possible to produce a safe and high-quality ripe bioplant cultivation nourishment in a very short time of only 36 days (about one month) after charging.

DESCRIPTION OF SYMBOLS 1 Fermenter 2 Deodorizing device 3a Sewage sludge hopper 3b Water sewage sludge hopper 4 Secondary material hopper 5 Inoculum hopper 6 Mixer 7, 8 Conveyor 9 Fermenter blower 10 Automatic bagging machine

Claims (6)

Combining sewage sludge compost consisting of a raw material mixture of sewage sludge and wood waste and water sewage sludge obtained as a sedimentation basin sediment in a water treatment plant, this mixture is mixed with Anoxybacillus sp. MS8 strain Planted cultivation soil fermented by (Accession Number FERM P-21818) .
  The planted cultivation soil according to claim 1, further comprising a lightweight material mixed therein. A first step of producing a sewage sludge compost by fermenting a raw material mixture obtained by mixing sewage sludge and wood waste with Anoxybacillus sp. MS8 strain (accession number FERM P-21818) ;
A second step of producing an intermediate mixture by mixing the sewage sludge compost and the water sewage sludge obtained as a sediment of a settling basin of a water purification plant ;
A third step of fermenting the intermediate mixture again with the Anoxybacillus sp.
A method for producing planted soil for cultivation.
In the second step,
The said sewage sludge compost 2 volume part or more and 5 volume part or less and the said water-sewage sludge 8 volume part or less 5 volume part or more are mixed in the ratio used as a total of 10 volume parts, It is characterized by the above-mentioned. Manufacturing method for planting culture soil. In the third step,
The method for producing a plant culture land according to claim 3 or 4, wherein the fermentation of the intermediate mixture is performed in an aerobic state. In the first step,
The method for producing a planting culture soil according to any one of claims 3 to 5, wherein the fermentation of the raw material mixture is performed in an aerobic state.

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