JP4240492B2 - Method for producing organic fertilizer and organic fertilizer - Google Patents

Description

  The present invention relates to an organic fertilizer production method for producing an organic fertilizer by fermenting an object to be treated such as animal excrement under an aerobic condition, and an organic fertilizer produced by the production method.

Generally speaking, an example in which livestock excreta is used as an organic fertilizer as an object to be treated has led the livestock industry to be obliged to properly handle livestock excrement by the livestock excretion law, etc., which came into effect in 1999. As a result, processing of livestock excrement by fielding, unearthing, etc. has been prohibited, and construction of composting houses and composting have been promoted.
Livestock excretion progresses through the composting process and the maturation proceeds, a. Reduction in filth, b. Reduced moisture content, c. Removal of harmful substances, d. Killing weed seeds and harmful microorganisms, e. Effectiveness of fertilizer components is achieved. In order to make this composting efficient, it is desirable to adjust the ratio of carbon and nitrogen appropriately and to elevate the temperature under aerobic conditions with a pH of neutral to alkaline. However, under such conditions suitable for composting, ammonia nitrogen contained in livestock excreta is likely to volatilize in the air, so that compost that has been matured has a lower nitrogen content. And since the compost | cure with low nitrogen content has low fertilization efficiency, it is the reality that it is difficult to use as a chemical fertilizer alternative fertilizer and the utilization scene is limited.
According to the Fertilizer Control Law, the minimum amount of nitrogen component in processed poultry manure is 2.5%, and if it is not secured more than this, it cannot be distributed as ordinary fertilizer. In addition, ammonia nitrogen that volatilizes during the fermentation process is a specified substance of the Air Pollution Control Law, and is a substance that requires appropriate management.

Conventionally, for example, the following methods (1) to (4) are known as techniques for preventing the volatilization of nitrogen in the composting process and not reducing the nitrogen content.
(1) Method of proceeding fermentation under anaerobic conditions In this method, organic substances such as lactic acid are decomposed by decomposing organic substances under conditions where the oxygen concentration in the object to be treated is low by treatment such as hydration, deaeration, or compression. It prevents acid volatilization by generating an acid and maintaining a low pH.

(2) Method of mixing acid such as sulfuric acid in order to lower pH This method is disclosed in, for example, JP-A-9-110570, and by adding acid such as sulfuric acid and acetic acid, ammonia sulfate and ammonia acetate Etc. to capture ammonia.
Specifically, an object supply device that supplies an object to be processed, an acid solution supply device that supplies an acidic solution, an object to be processed from the object supply device, and an upper solution from the acid solution supply device A mixing apparatus using a manufacturing apparatus that includes a mixing device that generates a mixture by mixing the components of the mixture and the pH value of the mixture to 7 or less and a drying device that dries the mixture from the mixing device by heating. Thus, the object to be processed from the object supply device and the acidic solution from the acidic solution supply device are mixed to form a mixture, and the pH value of the mixture is set to 7 or less. And the mixture from a mixing apparatus is heated with a drying apparatus, the water contained in a to-be-processed object is evaporated, and it dries. At this time, since the pH value of the mixture is 7 or less, the dissociation constant increases and ammonium ions increase, while ammonia decreases and ammonia is hardly released into the gas phase in the drying process. It is possible to prevent a decrease in ammonia nitrogen in the product and retain the ammonia nitrogen in the object to be treated after drying.

(3) Mixing treatment method of lime superphosphate This is a method in which lime perphosphate having an acidic pH is mixed with an organic substance to trap ammonia in the lime superphosphate.
(4) The method of composting the feces of the egg-laying hens raised in the undress poultry house for a short time with a vertical closed fermenter has been used.

JP-A-9-110570

  By the way, in the prior art mentioned above, the anaerobic fermentation of (1) has a slow decomposition rate of organic substances, removal of harmful substances and the like is insufficient, and the application method of the product has many problems. Further, the method (2) of mixing sulfuric acid is dangerous because sulfuric acid is used, and the apparatus is also increased in size. The method (3) of mixing phosphoperphosphate has problems such as high cost and low effect of preventing reduction in nitrogen content. The method (4) has a narrow application range and is not general and requires specific facility equipment. As described above, all of the conventional techniques have problems and are not widely used.

The present invention has been made in view of the above problems, and without providing a dedicated device, sulfuric acid is easily and safely generated in the organic matter treatment process, and the pH of the object to be treated is lowered by the sulfuric acid to produce ammonium sulfate. It aims at providing the manufacturing method and organic fertilizer of the organic fertilizer which prevented volatilization of ammonia nitrogen by capturing, and aimed at prevention of the nitrogen content fall of a to-be-processed object.

The method for producing an organic fertilizer according to the present invention for achieving such an object is the method for producing an organic fertilizer in which an organic fertilizer is produced by fermenting an object to be treated in which sulfur-oxidizing bacteria are present under aerobic conditions. An object to be processed is deposited, and sulfur is added to the deposited object to be processed . The sulfur-oxidizing bacteria are generally attached to the object to be treated mainly by the present invention, but if the object to be treated is sterilized, the sulfur-oxidizing bacteria are inoculated. Good. In addition, it is a matter of course that a sulfur-oxidizing bacterium may be separately inoculated to promote the reaction even if the object to be treated has sulfur-oxidizing bacteria attached to it.

  Thus, when sulfur is added to the object to be treated and fermentation is performed under aerobic conditions, sulfur is oxidized by sulfur-oxidizing bacteria, and sulfuric acid is generated. In the fermentation process, the reaction of the object to be processed tends to be acidic due to the generated sulfuric acid, and the volatilization of ammonia is reduced. The produced ammonia is captured as ammonium sulfate. This prevents a decrease in the nitrogen content of the object to be processed and produces an organic fertilizer with a high nitrogen concentration and an extremely high nitrogen fertilizer effect. This organic fertilizer can be used as an organic fertilizer with enhanced nitrogen fertilizer effect.

And, the object to be processed obtained by the deposited sulfur added and mixed 0.2-2 times the total nitrogen content, then, configured to fermentation the pH under aerobic conditions of neutral to alkaline It is said. If the amount is less than 0.2, the reaction is small and it is difficult to obtain the effect. Exceeding twice the amount is not preferable because it becomes too acidic.
Theoretically, one sulfur atom is present for every two nitrogen atoms, so that nitrogen is captured as ammonium sulfate. In this case, 1.3 times the amount of nitrogen is sufficient. In actual situations, the amount to be added is determined based on various conditions such as how much the volatilization amount of nitrogen is suppressed, how much the pH of the treated product is adjusted, and how much residual amount of unoxidized sulfur is allowed. It will be.
It is desirable to analyze the total amount of nitrogen by an official method such as perchloric acid decomposition, but the nitrogen concentration in various animal dung etc. has been investigated by past literatures. decide.
For example, if the amount is set to 1.0 to 1.6 times, a decrease in the nitrogen content of the workpiece is reliably prevented.

  Moreover, it is set as the structure which forcedly ventilates or stirs the said to-be-processed object in a fermentation process as needed. This ensures aerobic conditions and promotes sulfur sulfation by sulfur-oxidizing bacteria.

Moreover, it is set as the structure which the said to-be-processed object is an animal excrement as needed. Effective use of animal excrement such as livestock is planned.
In this case, the animal excrement is chicken dung. Since chicken manure has a higher original nitrogen concentration than other animal manure, the application of this technology makes it possible to create organic fertilizers with high added value and enhanced nitrogen fertilizer, which is extremely useful. Further, in many cases, a large-scale composting facility is already installed, and the present technology can be easily applied to the existing facility, so that commercialization is facilitated.

  And the organic fertilizer of this invention for achieving the said objective exists in the organic fertilizer manufactured by the said manufacturing method. It becomes an organic fertilizer with a high nitrogen content, and a high and stable nitrogen fertilizer effect can be expected.

  According to the present invention, it is possible to reduce the volatilization of ammonia in the object to be treated by simple treatment of adding sulfur to the object to be treated, and to capture the generated ammonia as ammonium sulfate. Organic fertilizer with high nitrogen concentration and extremely high nitrogen fertilization effect can be provided by suppressing a decrease in the nitrogen content of the product. Therefore, organic fertilizer with a high nitrogen content can be produced inexpensively and safely without introducing new facilities and operations, and effective use such as agricultural production can be achieved.

Hereinafter, the manufacturing method and organic fertilizer of the organic fertilizer which concern on embodiment of this invention are demonstrated in detail.
If the manufacturing method of the organic fertilizer which concerns on embodiment of this invention is demonstrated in the case of broiler chicken excrement which is excrement of an animal as a to-be-processed object, for example, 0.2-2 of total nitrogen amount will be given to this chicken manure. Double the amount, preferably 1.0 to 1.6 times the amount of sulfur is added, and the treated material is fermented under aerobic conditions in the presence of sulfur-oxidizing bacteria. In the fermentation process of the object to be treated, aeration or stirring is forcibly performed.

  Specifically, as shown in FIG. 1, for example, an open scoop type stirring device is used. This facility has a length of 90 m, a deposition width of 5 m, and a deposition height of 1.5 m, for example, and can process a workpiece of about 600 t. The material to be treated is broiler chicken manure, but contains sawdust used as a bedding material. In addition, about 10% of sulfur powder is added to broiler chicken manure to allow the fermentation process to progress, and the sulfur-oxidizing bacteria are proliferated and prepared as a sulfur-oxidizing bacteria inoculation source.

  Then, an object to be treated is brought into an open scoop type stirring device by a dump truck from a broiler farmer, and after broiler chicken manure is deposited, a sulfur-oxidizing bacteria inoculation source and sulfur powder are mixed and added by a front loader. As a result, inoculation with sulfur-oxidizing bacteria is promoted, prompt oxidation of sulfur is promoted, and sulfur is uniformly mixed. The amount added is about 200 kg of inoculum and about 100 to 200 kg of sulfur powder for 10 t of chicken manure.

The object to be treated is stirred with a stirrer about twice a day after sulfur addition to supplement oxygen and mix materials to promote aerobic fermentation. If the water content is reduced too much, the production of sulfuric acid from sulfur may be hindered, so water is sprayed.
As a result, sulfur is oxidized by sulfur-oxidizing bacteria, and sulfuric acid is generated. The reaction of the object to be processed becomes acidic and the volatilization of ammonia is reduced by this sulfuric acid. That is, the pH of the treated product is clearly lowered. Further, the EC of the treated product rises in response to the time when the pH is lowered. This indicates that the added sulfur was oxidized to produce sulfuric acid. A decrease in pH of the treated product suppresses the volatilization of ammonia. The produced ammonia is captured as ammonium sulfate. 30 to 60 days later, after primary fermentation, EC is measured to confirm the degree of sulfuric acid production. For example, it is pelletized with a pellet molding machine, weighed and packaged, and shipped as organic fertilizer.

  The organic fertilizer produced in this way is prevented from lowering the nitrogen content of the object to be treated, becomes an organic fertilizer with a high nitrogen concentration and a very high nitrogen fertilization effect, and a high and stable nitrogen fertilization effect can be expected. That is, the nitrogen content of the organic fertilizer is kept much higher than that of no treatment. Since the total carbon content remains almost the same as untreated, the C / N ratio (carbon / nitrogen ratio) of the treated product is kept high, and it can be used as an organic fertilizer with very fast nitrogen fertilization. .

Experimental example

Next, experimental examples will be described. Experiments were conducted in which the state of fermentation was compared between a sulfur-added section in which sulfur was added to chicken manure and fermented, and a non-treated section in which fermentation was performed without adding sulfur to chicken manure as a comparative example.
Chicken dung (chicken breed: Rhode Islandlet, age: 352 days, food type: New Select 17), sulfur flower (99.9%, 200 mesh grain size, made by Matsuo Kasei Co., Ltd.) ) Was prepared. After thoroughly mixing and homogenizing the above chicken dung without any bedding, 240 g of sulfur husk and 240 g of rice husk were added to 12.0 kg of chicken dung and mixed well. Similarly, 240 g of rice husks were added to 12.0 kg of chicken manure in the untreated area, and similarly mixed well.

  As an experimental device, a small composting experimental device “Kaguyahime” manufactured by Fujihira Industry Co., Ltd. was used. As shown in FIG. 2, this apparatus has a stainless steel cylindrical container housed in a wooden heat-retaining container, and supplies oxygen by aerating the experimental material from the lower part with a pump to promote composting. It is a device that can. The stainless steel container is hermetically sealed and can capture the gas generated in the composting process. The experimental materials for the sulfur-added group and the non-treated group were filled in stainless steel containers, respectively, and 0.6 mL / S was vented by a pump. A thermometer was inserted into the center of the experimental material, and the product temperature was measured over time. The experimental material was taken out over time, and the analysis sample was sampled and stirred again.

  And the following analysis was performed about the analysis sample. The sample was measured for moisture by a method at 105 ° C. for 24 hours, pH was measured by a glass electrode method, and EC was measured by an EC meter. The dry pulverized product was measured for the estimated total carbon by an electric furnace at 550 ° C. for 8 hours. In addition, total nitrogen was measured by autoanalyzer after sulfuric acid hydrogen peroxide decomposition.

The test results are shown in FIGS. As shown in FIG. 3, TN (total nitrogen amount) continues to decrease in the non-treated section, but there is little decrease in nitrogen in the sulfur-added section.
In addition, as shown in FIG. 3, TC (total carbon amount) is almost the same in both the sulfur-added zone and the untreated zone, and the decomposition of organic matter is progressing in the sulfur-added zone. Recognize. The result of calculating the C / N ratio from the measured carbon content is shown in FIG. It can be seen that the C / N ratio continues to increase in the untreated section and the C / N ratio continues to decrease in the sulfur addition section. From this, it can be said that in the sulfur-added section, ammonia volatilization was suppressed by the generated sulfuric acid, and as a result, the ratio of ammonium sulfate in the total nitrogen was increased and the nitrogen fertilization effect was increased.

Further, as shown in FIG. 5, only 23% of the raw material remains in the untreated section, whereas about 50% remains in the sulfur-added section.
Furthermore, as shown in FIG. 6, the pH of the sulfur-added zone is lower than that of the untreated zone from a fairly early stage, and it seems that sulfuric acid production from sulfur is carried out from the beginning, but the increase in EC is obvious. After about a month after the aerobic treatment, the peak of sulfuric acid production seems to be after this period.

  From the above results, the following is considered. It was found that nitrogen loss was suppressed by mixing sulfur with chicken manure and aerobic fermentation, and both the amount of residual nitrogen and nitrogen concentration were greatly improved. Since the decomposition of carbon proceeded almost the same as in the non-treated section, the C / N ratio increased to about 10 in the untreated section, but was kept low at about 5. The original form of nitrogen is mainly composed of proteins, amino acids, uric acid, etc. with relatively large molecular weights, whereas the form of nitrogen after aerobic fermentation in the sulfur-added zone has a significantly increased proportion of ammonium sulfate. It is thought that there is. This means that the nitrogen fertilization effect of the treated product in the sulfur-added zone may have a significantly quicker character than the untreated zone.

  In the above embodiment, the organic fertilizer is manufactured using an open scoop stirrer. However, the present invention is not necessarily limited to this, and other appropriate devices such as an open rotary stirrer facility are used. It can be changed as appropriate. Further, as an object to be treated, the example of chicken manure has been described, but the present invention is not limited to this, and can also be applied to livestock excreta other than chicken manure, and food waste, pruned branches, sewage sludge, etc. Of course, the present invention may be applied to any organic matter to be treated such as organic waste.

It is a figure which shows the manufacturing method of the organic fertilizer which concerns on embodiment of this invention with an example of stirring facility. It is a figure which shows the structure of the apparatus used in the experiment example of this invention. It is a graph which shows transition of the total carbon by a sulfur addition, and the total nitrogen content by an experiment example. It is a graph which shows the influence which it concerns on the experiment example and sulfur addition has on the C / N ratio of the to-be-processed object in fermentation. It is a graph which shows the influence which it concerns on an experiment example and sulfur addition has on the nitrogen residual rate. It is a graph which shows the influence which the sulfur addition has on the pH and EC of the to-be-processed object during fermentation concerning an experiment example.

Claims (4)

In the method for producing organic fertilizer, fermenting an object to be treated containing sulfur-oxidizing bacteria under aerobic conditions to produce organic fertilizer,
The object to be treated is deposited, sulfur is added to the deposited object to be treated in an amount of 0.2 to 2 times the amount of total nitrogen, and then the pH is adjusted to neutral to alkaline aerobic conditions. A method for producing an organic fertilizer, wherein the fermented product is forcibly aerated or stirred in the fermentation process while being fermented underneath. 2. The method for producing an organic fertilizer according to claim 1, wherein the object to be treated is animal excrement. The method for producing an organic fertilizer according to claim 2, wherein the animal excrement is chicken dung. The organic fertilizer manufactured by the manufacturing method of the said Claims 1 thru | or 3.