JP2007031232A - Composting method by which ammonia odor is suppressed and composting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel composting method by which ammonia odor is suppressed over the whole composting step, and the compost is manufactured at a remarkably low cost. <P>SOLUTION: The composting apparatus 1 is provided with a stirring mechanism 2 for turning up and down the compost raw material CP in a treating vessel 11, a ventilation mechanism 3 for sending oxygen to the compost raw materia CP in the treating vessel 11, an ammonia monitoring mechanism 6 for monitoring ammonia producible from the compost raw material CP under the treating, and a spraying mechanism 7 for spraying oil O to the compost raw material CP in the treating vessel 11. The spraying mechanism 7 is provided with a heater 74 for properly heating the oil to be sprayed. The composting is started by adding the adequate quantity of oil into the compost raw material CP and is carried out while monitoring the generation of ammonia during a composting step and when the generation of ammonia is detected, the oil is sprayed on the compost raw material CP. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a composting method for suppressing ammonia odor that may be generated from garbage etc. during composting, for example, when composting garbage etc. discharged from a home, and in particular, the entire composting process The present invention relates to a novel composting technique that can reduce ammonia odor over a wide range and that can be realized at an extremely low cost.

In recent years, the realization of an energy-saving or (resource) recycling society has been rapidly increasing socially, and as a part of such a policy, for example, composting methods such as garbage are attracting attention. This composting method is a method of recycling raw garbage as compost while reducing the amount of waste, and is highly evaluated as part of realizing a recycling society.
However, in reality, the composting method has not yet been widely used, and this is thought to be due to a bad odor such as ammonia generated from compost raw materials such as garbage in the composting process. .
For this reason, many attempts have been made so far to reduce the ammonia odor generated from the compost raw material, and many of them have removed the ammonia odor generated from the compost raw material. Based on the idea of deodorizing, various inorganic and organic adsorbents and additives have been developed. However, in reality, there are almost no such methods that are practically and objectively verified for certain effects.

Under such circumstances, the present inventor does not accept the generation of ammonia odor, but rather suppresses the generation itself, so that it advances the development of ammonia odor reduction based on the idea of deodorization (attention). (See, for example, Patent Documents 1 to 3).
For example, Patent Document 1 is an invention for reducing the ammonia odor by the microorganism Bacillus licheniformis. The ammonia odor can be reduced by 60%, and a corresponding effect has been achieved. However, in the present invention, it is difficult to reduce the total composting, and there is still room for improvement in this respect.
In Patent Documents 2 and 3, a biodegradable resin is added to a compost raw material to reduce ammonia odor and amine odor, and this has also been confirmed to have a corresponding effect in reducing off-flavor. However, in Patent Document 2, for example, the reduction effect is limited to the post-composting middle stage where the biodegradable resin starts to be decomposed, and a biodegradable resin that is several times more expensive than general-purpose plastic is applied. There was room for improvement in this regard. Further, in Patent Document 3, it became possible to reduce bad odor throughout the composting process. First, a biodegradable resin was mixed with compost raw materials to make an intermediate treatment compost, Since treated compost is added again to the compost raw material to achieve composting, there is still room for development in terms of cost and much labor.

Traditionally, it has been handed down as a method to reduce the ammonia odor, although the composting rate is slow (lower), but the C / N ratio (carbon to nitrogen ratio) of the compost raw material can be adjusted (increased). It is coming. Certainly, nitrogen seems to be correct because it is a constituent atom of ammonia, but in reality, there is a clear basis for how and why ammonia odor can be suppressed by adjusting the C / N ratio. do not do. On the contrary, in reality, it is often impossible to greatly reduce the ammonia odor by simply adjusting the C / N ratio, and no reports have been confirmed that the ammonia odor was completely suppressed. In other words, the suppression of the ammonia odor by adjusting the C / N ratio sounds plausible at first glance, but it can be inferred that the C source for suppressing the ammonia odor is actually limited.
JP 2001-261474 A JP 2000-239085 A Japanese Patent Laid-Open No. 2002-60291

  The present invention has been made in view of such a background, and can suppress ammonia odor almost completely throughout composting, and enables operation at low cost in accordance with the actual situation. In addition, we have attempted to develop a reliable composting method that elucidates the suppression effect and its mechanism.

  That is, the composting method that suppresses the generation of the ammonia odor according to claim 1 is a method of composting compost raw materials mainly composed of organic waste such as garbage by microbial decomposition, wherein the compost raw materials are In this method, an appropriate amount of oil is added to start composting, and the fatty acid generated from the oil undergoes decomposition from the carboxyl group side while repeatedly undergoing β oxidation during the composting process, and this β oxidation Each time, a short intermediate having two carbons is generated, and the ammonia generated from the compost raw material is neutralized by the remaining intermediate product from which two carbons are removed, thereby suppressing the generation of ammonia odor. Yes, during the composting operation, processing is performed while monitoring the generation of ammonia. It is characterized by the fact that additional oil is sprayed on the material.

  The composting method that suppresses the generation of ammonia odor according to claim 2 is characterized in that, in addition to the requirement of claim 1, waste food oil is applied as the oil added to the compost raw material. It is.

  In addition to the requirement of claim 1 or 2, the composting method that suppresses the generation of ammonia odor according to claim 3 is characterized in that the oil added to the compost raw material is 10 on a dry weight basis with respect to the total compost raw material. It is characterized by being added in a proportion of more than 50% by weight and less than 50% by weight.

Moreover, the composting device that suppresses the generation of the ammonia odor according to claim 4 incorporates a treatment tank in the device main body, inputs a composting material mainly composed of organic waste, and ferments the composting material by microbial decomposition. An apparatus for composting, the apparatus comprising a stirring mechanism for switching compost raw materials in the treatment tank at an appropriate frequency, and an aeration mechanism for supplying oxygen to the compost raw materials in the treatment tank, and further being processed At least a temperature measuring mechanism for measuring the temperature of the compost raw material, an NH ₃ monitoring mechanism for monitoring ammonia that may be generated from the compost raw material being processed, and a spraying mechanism for spraying oil to the compost raw material stored in the processing tank The spraying mechanism is provided with a heater for appropriately heating the sprayed oil. Is.

The above-described problems can be solved by using the configuration of the invention described in each of the claims.
That is, according to the first aspect of the present invention, the generation of ammonia odor can be suppressed throughout the composting process by an extremely simple operation of adding oil to the compost raw material. For this reason, as a user, this composting method can be implemented very easily and at a low cost, almost the same as a normal composting method. Further, in the present invention, the mechanism for suppressing the ammonia odor is clarified and the effect is demonstrated, so that the social reliability is high and the user can use it with peace of mind.
Incidentally, conventionally, oil in compost raw materials was thought to have an adverse effect on composting, but in the present invention, it was found that rather moderate addition of oil can suppress the generation of ammonia odor, The inhibitory effect (time) has been elucidated and the present invention has been achieved. In other words, the present invention is an extremely excellent technique in terms of an ammonia odor suppression composting technique with demonstration.

  According to the invention described in claim 2, since the waste food oil is used as the oil added to the compost raw material, the waste food oil can be recycled and the composting cost can be reduced at once. In other words, 500,000 tons of waste food oil is generated annually in Japan and is itself difficult to dispose of. Therefore, the present invention that uses this is not only for recycling waste food oil but also for composting costs. The cost can be further reduced. In addition, since the waste food oil itself is a situation that is difficult to process as described above, in some cases, it is possible to pay for it reversely, which can greatly promote the spread of composting that contributes to a recycling society.

  According to the invention described in claim 3, the suitable addition ratio of the oil that suppresses the generation of the ammonia odor throughout the composting is made concrete. Of course, since this ratio is a numerical value obtained by composting a specific raw material under certain conditions, it can be considered that it varies depending on the type of composting raw material, composting conditions, and the like. However, this numerical value is a numerical value after elucidating the suppression mechanism of ammonia odor, and its significance is significant as one reference value. In addition, this numerical value itself can be an index for further development in the future, and in this sense, the presentation of this specific numerical value is highly useful.

  According to the invention of claim 4, during the composting process, the process is carried out while monitoring ammonia that can be generated from the compost raw material, and when ammonia is detected, the oil is sprayed. Equipment can be provided. That is, normally, there are many kinds of garbage such as those with a lot of moisture in the garbage itself, those containing a lot of oil (min) and those containing little oil (min), and various properties. For this reason, it is extremely difficult to determine the optimum amount of oil to be added to the composting raw material when throwing the garbage into the composting device, and the oil is sprayed according to the properties of the composting raw material being processed. It can be said that the form is an easy-to-use device that conforms to such a situation. Moreover, since detection of ammonia, spraying of oil, etc. can be performed automatically, the user can use it in the same manner as a conventional household garbage processing machine without much effort. Furthermore, since the spraying mechanism for spraying oil is provided with a heater, for example, oil that is solid at room temperature is dissolved in a liquid state and sprayed onto the compost raw material, or the oil depending on the temperature of the compost raw material being processed. Can also be heated.

  The present invention is a composting method in which oil is added to organic waste such as garbage (compost raw material CP) so as to hardly generate odors such as ammonia odor and amine odor, and throughout the composting process. It can suppress the ammonia odor almost completely. The deodorization principle has clarified that the neutralization effect by the intermediate, that is, the fatty acid generated in the middle of the decomposition of oil greatly contributes. Of course, the effect of reducing ammonia is considered to be fixed in the fungus body, but it was confirmed that the fixed amount was very small (less than 10% in the calculation example).

  Conventionally, such oils are difficult to be microbially decomposed per se, make it difficult to maintain aerobic conditions where microorganisms are activated, and further prevent microorganisms from coming into contact with organic matter. However, composting tended to prevent good organic matter decomposition and avoid it. However, in the present invention, it has been found that by adding an appropriate amount of such oil to the compost raw material CP, the generation of ammonia odor that can be generated from the compost raw material CP is found, and further, the mechanism and effect thereof have been clarified. It is a method of making it.

  Hereinafter, the present invention will be described based on the following examples. In the description, an experiment A clarified the effect of reducing the ammonia odor and the deodorizing principle when applying lard, which is fat, as an example of oil and adding it to the compost raw material CP (this will be referred to as Example 1). ), And then an experiment B (this is referred to as Example 2) showing the effect of reducing the odor of ammonia when mineral oil is applied as an example of another oil and added to the compost raw material CP, and then Two types of composting apparatuses 1 and 1A embodying such a composting method will be described. In addition, as organic waste, various things such as organic waste such as industrial waste and animal manure can be applied as well as food waste.

(1) Experiment A
(i) Compost Raw Material First, as the compost raw material CP, a commercial rabbit food (manufactured by Easter Co., Ltd.) was used in consideration of the advantage that reproducible data can be obtained as an alternative to food waste. The elemental analysis values of carbon and nitrogen of this rabbit food were 44.3% and 2.40%, respectively, and the C / N ratio was about 18.5. The rabbit food was ground to a particle size of about 1 mm with a food processor and mixed with sawdust, which is a breathable material, and inoculum, which is a microorganism material. The ratio was such that the dry weight ratio was RF (rabbit food): sawdust: inoculum 13: 9: 1, and this was used as the compost raw material CP. The mixed compost raw material CP was adjusted to have an initial pH of around 8.0 and an initial moisture content of about 60%.
In the experiment, as shown in the table of FIG. 1, the presence or absence of addition of lard (marine puree made by Marine Food Co., Ltd.) as fat was changed, and Run A without lard and lard on a dry weight basis. Composting was performed with Run B, Run C, Run D, and Run E added to 10%, 25%, 33%, and 40% of the total compost raw material CP.

(ii) Composting operation FIG. 2 is a schematic diagram of an experimental apparatus that collects ammonia and carbon dioxide generated from the compost raw material CP when composing the above-described Run A to Run E. Reference symbol J1 in FIG. J2 is a CO ₂ trap, J3 is a bubbler, J4 is a rubber plug, and J5 is a stainless screen. Reference symbol J6 in the figure denotes a minireactor (small reactor), which is made of, for example, a cylindrical heat-resistant glass having a diameter of 45 mm and a height of 100 mm, and the rubber plug J4 having glass tubes for ventilation above and below it. It is attached. Further, reference numeral J7 in the figure denotes a tedlar bag (5 liter type A manufactured by Omi Odo Air Service Co., Ltd.) that collects exhaust gas discharged from the minireactor J6 by composting. Moreover, the code | symbol J8 in a figure is an incubator (The thermostat IS800 by Yamato Scientific Co., Ltd.).
Then, the compost raw material CP (Run A to Run E) adjusted as described above was filled into the minireactor J6, installed in the incubator J8, and composted while being vented from the bottom of the minireactor J6.

The air vented into the minireactor J6 is led to a flask containing 0.1N NaOH aqueous solution to remove carbon dioxide (CO ₂ trap J2) and then contains distilled water to prevent the compost raw material CP from drying. Was introduced into the flask (bubbler J3), saturated with moisture, and then led to the bottom of the minireactor J6. The aeration rate was maintained at 5.3 ml / min. It has been confirmed by preliminary experiments that aerobic conditions are maintained throughout composting at this ventilation rate. The temperature in the incubator J8 at the start of composting was 30 ° C., the temperature was raised at a constant rate so that the set temperature was 60 ° C. after 12 hours had elapsed, and the temperature was kept constant at 60 ° C. The composting period was 10 days.

The exhaust gas discharged from the mini-reactor J6 is collected in the Tedlar bag J7, and the Tedlar bag J7 is replaced every 12 hours, and the concentration of carbon dioxide and ammonia in the collected exhaust gas is measured using the Kitagawa-type detector tube (Gwangmyeong). Measured with AP-1) manufactured by RIKEN. Also, the volume of the collected exhaust gas is measured with a dry gas flow meter (NDP-2A-T manufactured by Shinagawa Seiki Co., Ltd.), and the amount of carbon dioxide generated every 12 hours is measured together with the measured value of carbon dioxide concentration. The carbon volatilization rate indicating the degree of decomposition of the raw material organic matter was determined from the cumulative amount generated. The carbon volatilization rate was defined as the ratio between the amount of carbon in the carbon dioxide gas volatilized in the exhaust gas and the carbon content of the rabbit food determined in advance by elemental analysis. Therefore, when the lard decomposes well and carbon dioxide gas exceeding the carbon content of the rabbit food is generated in the experiment in which lard is mixed, the carbon volatilization rate may exceed 100%. Similarly, the amount of ammonia generated was determined from the measured value of the ammonia concentration. The decomposition rate based on carbon dioxide was calculated as the lard decomposition rate accompanying composting. The lard decomposition rate based on carbon dioxide is the amount of carbon dioxide generated during composting with or without lard added, and the amount of carbon dioxide generated as a result of lard decomposition. Calculated by dividing by the amount of carbon in lard.
Further, for the purpose of uniform progress of composting, the mini-reactor J6 was opened once a day, and a reversing operation for mixing and stirring the compost solid phase was performed. And the sample was extract | collected with the turning over, and the moisture content, pH, and microorganism concentration were measured.

(iii) Measurement of microorganism concentration The dilution plate method was applied to the measurement of microorganism concentration. Nine times the amount of sterilized water was added to the collected compost sample and subjected to a morphogenic treatment at 10,000 rpm for 10 min. The compost suspension was appropriately diluted with sterilized water and smeared on a Trypticase-soy agar medium at 60 ° C. For 3 days. The bacterial cell concentration was arranged as the number of colonies formed per unit compost dry weight.

(iv) Fat Extraction by Soxhlet Method A soxhlet fat extractor (B-811 manufactured by Shibata Kagaku Co., Ltd.) was used to measure the amount of residual fat in composting with lard added. About 100 ml of diethyl ether was placed in a solvent container and attached to the lower part of the extractor, and a cylindrical filter paper containing 1 g of sample was attached to the upper part of the extractor for extraction. After the extraction operation, it was dried in an incubator at 60 ° C. for about 3 hours, allowed to cool in a desiccator for about 15 minutes, and then weighed. From the amount of fat contained in 1 g of the sample, the amount of fat remaining per one minireactor J6 was determined. In addition, the extraction with Soxhlet also extracts the fat originally contained in the rabbit food, so the residual fat amount of Run A without the addition of lard is subtracted from the residual fat amount in the composting with addition of lard. The amount of lard decomposition was calculated based on the weight and the ratio of lard added to the compost raw material CP.

(v) Measurement of ammonia nitrogen in compost raw material A steam distillation method was used to measure ammonia nitrogen and NH ₄ ⁺ -N present as ammonium salt in the compost raw material CP. First, the compost sample was placed in a 1 g flat bottom flask at a wet weight, 30 ml of 2N NaOH aqueous solution was added, and ammonium ions present in the sample were volatilized as ammonia. Subsequently, separately generated water vapor was sent into a flat bottom flask through a glass tube, and the volatilized ammonia was collected in 20 ml of 0.02NH ₂ SO ₄ aqueous solution. The liquid thus obtained was adjusted to a pH of around 6.5 to 7.5 using a 1N NaOH aqueous solution and used as a sample for NH ₄ ⁺ -N measurement. NH ₄ ⁺ -N in the prepared specimen was measured using F-kit ammonia (manufactured by Roche Diagnostics).

(vi) Results and Discussion FIG. 3 compares changes in carbon dioxide generation over time between Run A without lard and Run D with lard added 33%. The amount of carbon dioxide generated by Run A and Run D is almost the same until 24 hours after composting, but after that, Run A continues to decrease, while Run D increases again, and there is a significant difference between the two. It was. This indicates that fat breakdown began after 24 hours of composting. In Run A, the carbon volatilization rate was about 50% after 240 hours of composting, whereas in Run D it was about 110%. The carbon volatility of Run D with lard added exceeded 100%. It was also found that lard was actively decomposed during the composting period because the value was higher than that of Run A without addition of.

  The change with time of the carbon dioxide standard lard decomposition rate in Run D is shown in FIG. Reflecting the fact that Run A and Run D generated similar amounts of carbon dioxide until the first 24 hours of composting, the decomposition rate was almost zero and constant, but after 24 hours, the decomposition rate increased. At first, it was about 30% in the end.

  FIG. 5 shows the change over time in the ammonia generation amount of Run A and Run D. In Run A, the ammonia generation amount began to increase rapidly from around 48 hours after composting, then reached a peak after 72 hours, and then decreased again, but then regenerated from 96 hours. On the other hand, in Run D, although a slight amount of ammonia was observed at the initial stage of composting, no ammonia was detected after 72 hours. From this result, it was confirmed that the addition of lard had a remarkable effect in suppressing the generation of ammonia odor.

  The time course of pH in Run A and Run D is shown in FIG. In Run A, the pH was maintained at a weak alkali of 8 or more throughout the composting period, and no significant change was observed. However, in Run D, the pH dropped rapidly from around 48 hours after composting. It was 6.5, approaching the value near neutrality. In composting, organic nitrogen in the compost raw material CP (nitrogen in the organic matter) is subjected to microbial decomposition, and the generated ammonia is once absorbed and adsorbed by the compost raw material CP, so that the pH of the compost raw material CP becomes 8 or more. It has become clear from previous research that ammonia gas is only generated for the first time. The reason why ammonia was not generated in Run D was that the pH dropped to about 8 or less from around 48 hours of composting, so it was considered that ammonia was trapped in the compost raw material CP even though it was generated. It was. Moreover, it was thought that it was the fatty acid produced | generated by decomposition | disassembly of lard that lowered pH to the acidic side in the composting which added lard.

Therefore, the presence of fatty acids that would have been produced in the compost raw material CP due to lard decomposition was confirmed. FIG. 7 shows the IR spectrum measurement results after 240 hours of composting of Run D to which lard was added. The IR spectrum showed absorption peaks characteristic of fatty acids and their salts in the vicinity of 1700 cm ^−1, confirming the presence of fatty acids, which are Lard's decomposition intermediates, in the compost raw material CP.

And if the neutralization of acidic substances, which are Lard's decomposition intermediates with fatty acids, can be considered as the reason for reducing the ammonia odor, Run D traps ammonia in the fat decomposition intermediates compared to Run A. As a result, the ammonium ion concentration should be higher. FIG. 8 compares the amount of nitrogen volatilized as ammonia gas in the composting of Run A and Run D with the amount of nitrogen present as ammonium ions in the compost raw material CP. The ammonium ion in compost raw material CP is 3.31 × 10 ⁻⁴ mol / batch larger in Run D than Run A, and this value is the difference in ammonia gas volatilization between Run A and Run D 3.6 ×. This corresponds to 91.8% of 10 ^-4 mol / batch. That is, 91.8% of the ammonia gas reduced by adding fat is retained as ammonium ions in the compost raw material CP. Therefore, it was confirmed that the ammonia gas reduction effect was mainly due to neutralization.

Another possible reason for reducing the ammonia odor is that ammonia may have been biosynthesized into the proteins constituting the cells and fixed in the cells. Then, the measurement result of the cell density | concentration of Run A and Run D was compared with FIG. The cell concentration increased for Run A and Run D by around 24 hours after composting, and became almost constant thereafter. In addition, there was a difference of about 10 times between Run A and Run D. From this result, it can be considered that about 9% of the reduced amount of ammonia gas generated in Run D was taken into the cells, but the measured value of the cell concentration was determined by other analysis. Since the error tends to be larger than the value, it is difficult to quantitatively indicate the amount of nitrogen taken into the cells. Qualitatively, it was found that the amount of nitrogen taken into the cells was higher in Run D.
In addition, even if lard decomposes, if there is something that temporarily stays as an intermediate such as fatty acid, or if there is something that is taken into the fungus body, even the weight-based decomposition rate of lard and carbon dioxide gas It was considered that the decomposed carbon dioxide standard decomposition rate did not match. Therefore, the decomposition rate of Run D in terms of weight and carbon dioxide was compared. After 240 hours of composting, it was about 80% on the basis of weight and about 30% on the basis of carbon dioxide, which proved that there was a considerable amount of decomposed lard not decomposed to carbon dioxide.

  The carbon dioxide standard lard decomposition rate in composting with different lard addition ratios is shown in FIG. It can be seen that the decomposition rate on the basis of carbon dioxide gas increased from around 24 hours of composting, and the decomposition of lard started from around this time. Further, it was found that the lard decomposition rate was not proportional to the amount of lard added because the lard decomposition rate was small as the lard addition ratio was large.

Moreover, the nitrogen volatilization rates of Run A to Run E are shown in FIG. As described above, in Run A, a large amount of ammonia was generated from around 48 hours, but it can be seen that in all cases of composting with addition of lard, generation of ammonia was suppressed. However, in Run B in which only 10% of lard was added, it was confirmed that the generation of ammonia started around 120 hours after composting. This was thought to be because the amount of Lard added was small, and the fatty acid that was an intermediate accompanying lard decomposition was insufficient in the latter half of composting. In Run C to Run E where the addition ratio of lard was 25% or more, almost no ammonia was generated throughout the composting period.
Although details are not shown here, it was found that composting with lard added to 50% or more makes it difficult to ensure air permeability, and aerobic conditions cannot be maintained and the composting reaction itself is inhibited. . For this reason, it was thought that the lard addition amount for reducing the ammonia odor is preferably more than 10% and less than 50%.

  Conventionally, adjusting the C / N ratio to a large value is said to be effective in preventing the generation of malodors, and the principle has been thought to be that nitrogen is taken into the cells. The addition of fat to the compost raw material CP carried out in the present invention (this experiment) is also to increase the C / N ratio. However, the results obtained by the present invention cannot be predicted by the conventionally known effect of adjusting the C / N ratio. The result of adjusting the C / N ratio with other raw materials is shown in FIG. 12 together with the result of the present invention. Here, cellulose powder is added to the sludge and the C / N ratio is adjusted to 9-30, but the ammonia suppression effect is very different, especially in the case of the present invention adjusted with fat. Is evident. In other words, the rough expression of adjusting the C / N ratio cannot accurately describe the effect of reducing odor. As described above, the effect of C / N ratio adjustment, which has been conventionally described, and the result of the present invention are completely different in the principle of malodor control. That is, in the present invention, it was confirmed that when the added fat was decomposed, an acidic decomposition intermediate was generated, and this played a significant role in neutralization. From the above results, it can be said that the result obtained by the present invention is a new finding beyond the scope of what has been said about the effect of C / N ratio adjustment.

(2) Experiment B
In Experiment A, the addition of lard had a significant effect on ammonia odor control, so it was confirmed whether the same effect could be obtained with lard, ie, oils other than animal fats. In this experiment B, hexadecane, which is a constituent component of mineral oil, was used as the oil.

(i) Method Rabbit hood (similar to Experiment A), sawdust as an air permeability improving material, and commercially available inoculum were mixed at a dry weight ratio of 13: 9: 1, and this was used as a compost raw material CP. Further, the mixed compost raw material CP was adjusted so that the initial pH was around 8.5 and the initial moisture content was about 60%. The experiment changed the presence or absence of the addition of hexadecane (component of mineral oil), composting without adding hexadecane is Run A ', and composting with hexadecane added to 33% of total compost raw material CP on a dry weight basis Was composted as Run B ′.
Composting raw material CP (Run A ′ and Run B ′) was charged into the minireactor J6 and aerated from the bottom to start composting. The minireactor J6 was installed in the incubator J8, heated from room temperature to 60 ° C. at a constant rate, and then composted at a constant 60 ° C. Moreover, the lid | cover of minireactor J6 was opened once a day in order to promote uniform composting, and the inside was mixed and stirred.

  The exhaust gas generated from the mini-reactor J6 is collected in the Tedlar bag J7, and the Tedlar bag J7 is replaced every 12 hours to measure the carbon dioxide and ammonia gas concentrations with the Kitagawa type detector tube, and the volume of the exhaust gas is dry gas. Measured with a flow meter. Subsequently, the carbon dioxide generation amount every 12 hours was determined from these measured values, and the carbon volatilization rate indicating the degree of decomposition of the raw material organic matter was calculated from the cumulative amount of carbon dioxide generation. The amount of ammonia generated was also measured every 12 hours. The composting period was 10 days.

(ii) Results and Discussion First, FIG. 13 shows changes over time in the amount of carbon dioxide generated during composting of Run A ′ and Run B ′. At the initial stage of composting, there is no difference in the amount of carbon dioxide generated, but after 96 hours, Run B 'exceeds Run A'. This is because the hexadecane added to the compost raw material CP is after 96 hours. Indicates that it has begun to be decomposed.

  Next, FIG. 14A shows the change over time in the amount of ammonia gas generated during composting of Run A ′ and Run B ′. There was no difference in the generation of ammonia between Run A ′ in which hexadecane was not added and Run B ′ in which hexadecane was added until 96 hours after the start of composting. However, after 96 hours of composting, the amount of run A ′ increased again, but the value of one Run B ′ was kept low. This result has shown that generation | occurrence | production of ammonia was suppressed by adding hexadecane. For comparison, FIG. 5 showing the amount of ammonia gas generated in Run A and Run D in Experiment A is shown again as FIG. 14B. When these were compared, it was found that when hexadecane was used, it took time for the suppression effect of ammonia generation to appear compared to lard, and the suppression effect was not as great as lard.

(iii) Conclusion Hexadecane (used as a representative mineral oil) is less effective in suppressing ammonia odor than lard and other animal and vegetable oils, and the timing is not generally composting, but it is definitely effective. Admitted.

Next, while explaining the degradation process of fats and oils, especially animal fats such as lard, the reason why the vegetable oils and fats are expected to have an ammonia reduction effect equivalent to that of animal fats and oils will be explained.
Animal and vegetable oils and fats are all triglycerides composed of fatty acids and glycerin. Animal fats and oils are relatively rich in saturated fatty acids, whereas vegetable fats and oils are characterized by many unsaturated fatty acids. Any of the fats and oils undergoes decomposition after producing fatty acids. In addition, when producing fat from fat, it is produced by a hydrolase (digestive enzyme) called lipase. FIG. 15 shows an example of the structural formulas of fatty acids and mineral oils contained in animal and vegetable fats and oils.

As shown in FIG. 15A, the fatty acid produced by the decomposition of animal fats has a carboxyl group (—COOH) at the end, and the decomposition proceeds by so-called β oxidation from this portion. Specifically, fatty acid oxidase acts on the C atom at the position of β and cuts while oxidizing the fatty acid (takes H ₂ ), and along with this, a short fatty acid (active acetic acid) with two carbon chains As an intermediate. The “position of β” will be described. As shown in FIG. 15A, first, the position of the carbon next to the carboxyl group (—COOH) is the position of α (α carbon). The position of carbon is the position of β (β carbon).
In this way, fatty acids are decomposed by β-oxidation. For example, palmitic acid (C ₁₅ H ₃₁ COOH) shown in FIG. 16 is composed of 16 C atoms, and therefore, cleavage occurs at seven locations due to the decomposition. In total, 8 molecules of active acetic acid are produced. Hereinafter, the β-oxidation of palmitic acid will be described in more detail.

(1) Activation of fatty acid First, one molecule of fatty acid (palmitic acid) is activated using one adenosine triphosphate (ATP). At this time, as shown in FIG. 16, coenzyme coenzyme A (CoA · SH) binds to the site where OH of the carboxyl group (—COOH) is removed and activates the fatty acid. In FIG. 16, the process of disassembling is shown in detail by adding a frame to a part where something is newly bonded in this way.

(2) Production of FADH ₂ Next, the H bound to the C atoms of α and β are removed one by one by the action of dehydrogenase (oxidation) to become FADH ₂ . At this time, a double bond is formed between the C atoms of α and β.
(3) Addition of H and OH of water Next, H of water (H ₂ O) is added to the C atom of α and OH is added to the C atom of β.
(4) Production of NADH ₂ Subsequently, by the action of dehydrogenase, two H at the β position are removed (oxidation), and NADH ₂ is formed. At this time, the C atom of β becomes a ketone group (> C = O), and the preparation for separating one active acetic acid is completed.

(5) Formation of activated acetic acid Next, the bond between the α and β C atoms is broken, and the α C atom is bonded with H of coenzyme A (CoA · SH), thereby generating one molecule of active acetic acid. In addition, the remaining portion of Coenzyme A, CoA • S, is added to the ketone group at position β to produce an active fatty acid with two fewer C atoms. This activated fatty acid then returns to the activation of (1) above, and repeatedly undergoes the same β-oxidation, and eventually all of them are decomposed into activated acetic acid having only two C atoms. . The generated active acetic acid is taken up by the cells and digested.

Thus, every time one molecule of active acetic acid is generated, one molecule of FADH ₂ and NADH ₂ is generated. In palmitic acid (16C), as described above, this cleavage by β-oxidation occurs seven times, and 8 Active acetic acid is produced. In the present invention, ammonia is neutralized by the fatty acid having two fewer C atoms produced in the decomposition process. For this reason, fatty acids having a larger number of carbon atoms are all composed of active acetic acid. It takes a long time to be cut, and the effect of neutralization continues and the neutralization ability tends to increase.

Next, the reason why vegetable oils and fats have the same ammonia reduction effect as animal oils and fats will be described.
As shown in the structural formula of FIG. 15 (b) above, vegetable oils and fats have a double bond between C atoms, but they contain a carboxyl group (—COOH) in the same way as animal oils and fats. It is thought that the decomposition will proceed. That is, since it contains the same carboxyl group as animal fats and oils in terms of the structural formula, it is considered that decomposition proceeds in the same manner.

  Moreover, the fatty acid composition of animal fats and oils and vegetable oils is shown in FIG. 17, FIG. From this table, it can be seen that animal fats such as lard are composed of linear fatty acids having about 20 carbon atoms, although the number of unsaturated double bonds is smaller than that of vegetable oils such as olive oil. . This indicates that vegetable oils and fats are very similar to animal fats and oils in terms of fatty acid composition. That is, since it is a fatty acid having the same number of carbon atoms, it takes a similar time until all of the fatty acid is cleaved into active acetic acid, and therefore, the neutralization ability is considered to be equivalent. Therefore, it is presumed that vegetable oils and fats can have the same ammonia odor reducing effect as animal oils and fats, both in terms of structural formulas and fatty acid compositions.

  The mineral oil does not contain a carboxyl group (—COOH) as shown in the structural formula of FIG. 15 (c) above, but the effect in Experiment B is that oxidation is first performed from the terminal C atom. This is thought to be due to the formation of carboxyl groups similar to vegetable oils and animal fats. Conversely, in the case of mineral oil, it is thought that it took time until the effect was exerted because a carboxyl group was first generated by oxidation to form a carboxyl group at the terminal C atom.

Next, an actual composting apparatus 1 that actually performs such a composting method will be described. Here, the composting apparatus 1 embodied as a household garbage processing machine will be described first.
In actual composting, unlike the experiments described above, there are many types of organic waste (garbage), and the properties are unspecified accordingly. Specifically, even just the raw garbage from home, meat, cereals, fruits, egg shells, fish, vegetables, chicken bones, etc., vary widely, so the moisture, pH, and fat content of compost raw material CP Variations and biases inevitably occur even in (oil content of the garbage itself). Therefore, it is considered extremely difficult to determine the optimum amount of oil to be added at the stage of putting garbage into the apparatus. For this reason, in reality, when throwing in garbage, a small amount of oil is first added to start composting, and during the composting process, the process proceeds while monitoring the generation of ammonia as needed. When the generation of ammonia is detected, it is considered practical to add (spread) oil according to the generation amount, the temperature of the compost raw material CP, and the like.

Accordingly, as shown in FIG. 19, for example, as shown in FIG. 19, the composting apparatus 1 incorporates a processing tank 11 for receiving the composting material CP inside the apparatus main body 10 having a substantially rectangular parallelepiped shape, and the composting material CP in the processing tank 11 is appropriately used. A stirring mechanism 2 that switches back at a frequency (timing), an aeration mechanism 3 that supplies oxygen to the compost raw material CP in the treatment tank 11, and a heating and heat insulation that heats and maintains the treatment tank 11 at a temperature suitable for the activity of degradable microorganisms. Oil O is sprayed on the compost raw material CP in the processing tank 11, the temperature measuring mechanism 5 for measuring the temperature of the compost raw material CP, the NH ₃ monitoring mechanism 6 for monitoring ammonia that can be generated from the compost raw material CP A spraying mechanism 7 is provided.
Further, the spraying mechanism 7 includes a heater 74, and heats and melts the oil O that is solid at room temperature, or heats the sprayed oil O to approximately the temperature of the compost raw material CP. It is something to do. Hereinafter, each component of the composting apparatus 1 will be described.

First, the processing tank 11 will be described. In this embodiment, the processing tank 11 has a semi-cylindrical shape, and is provided with a wire net-like screen 12 having a large number of small holes 12a formed below. In addition, this screen 12 is for ensuring the air permeability of the compost raw material CP accommodated in the processing tank 11. FIG.
In addition to the microbial material that decomposes garbage (organic waste), the processing tank 11 is filled with sub-materials such as small wood chips and sawdust that form an environment suitable for the inhabiting of these microorganisms. . Such sub-materials provide moderate air and moisture to microorganisms and become a dwelling (hotbed) that forms a favorable growth environment for microorganisms. It is also responsible for the adjustment effect to improve.
Organic wastes such as garbage are put into secondary materials where degradable microorganisms live, and are decomposed by microorganisms to be composted. The “compost raw material CP” described in the present specification mainly indicates organic waste (garbage), but also includes the above-mentioned microbial materials and sub-materials such as wood chip chips.

  In addition, as microorganisms for decomposing organic waste such as garbage, bacteria that are mainly active in an aerobic environment are used. Especially at high temperatures of about 60 ° C., thermophilic bacteria mainly composed of the genus Bacillus are It greatly contributes to fermentation. Of course, various microorganisms appear with the type of organic matter, its degradation status, or the progress of composting. For example, actinomycetes are known to be active in the latter half of composting. .

Next, the stirring mechanism 2 will be described. In this embodiment, the stirring mechanism 2 is configured by attaching a ribbon-like blade 22 in a spiral state to a rotating shaft 21 that is installed substantially horizontally, and the blade 22 is driven by driving the rotating shaft 21. The composting material CP in the processing tank 11 is rotated and stirred and mixed. Such stirring not only mixes the compost raw material CP but also makes contact with oxygen and microorganisms and has an effect of improving the aerobic environment. For this reason, if air (air) is sent to the compost raw material CP in accordance with the stirring operation, the aerobic environment can be further promoted.
In this embodiment, horizontal axis agitation in which the rotation shaft 21 is arranged in the horizontal direction is not necessarily limited to this, but a vertical axis agitation in which the rotation axis 21 is arranged in the vertical direction is adopted. Is also possible.

  Next, the ventilation mechanism 3 will be described. For example, as shown in FIG. 19, the ventilation mechanism 3 includes a fan 31, which takes in air (air) from the outside into the apparatus main body 10 and supplies oxygen to degradable microorganisms. Note that, by driving the fan 31, carbon dioxide gas, moisture, ammonia, and the like discharged from the compost raw material CP can be discharged to the outside.

Next, the heating / warming mechanism 4 will be described. For example, as shown in FIG. 19, the heating / warming mechanism 4 includes a heater 41 for heating the treatment tank 11, and maintains the degradable microorganisms at a substantially constant temperature (for example, about 60 ° C.). is there.
In addition, when the processing tank 11 and the apparatus main body 10 which covers this are formed, for example with a heat insulating material etc., and the heat | fever emitted when microorganisms decompose | disassemble the compost raw material CP by this can be reused for the heat insulation of the compost raw material CP Since the heat insulating material substantially functions as the heating and heat retaining mechanism 4, the heating means (heater 41 and the like) as a device can be omitted.

  Next, the product temperature measuring mechanism 5 will be described. The product temperature measuring mechanism 5 includes a temperature sensor 51 and measures the temperature of the compost raw material CP being processed. The temperature sensor 51 is not limited to simply monitoring the temperature of the compost raw material CP, but transmits the data (product temperature) measured by the sensor to, for example, the spraying mechanism 7, and the oil O sprayed on the compost raw material CP is A utilization method such as spraying in a state heated to about this temperature is also conceivable. If the oil O sprayed on the compost raw material CP is heated and sprayed at approximately the same temperature as the compost raw material CP, there is no concern that the oil O will adversely affect the decomposition of the compost raw material CP, and the composting will be further promoted. Can do.

Next, the NH ₃ monitoring mechanism 6 will be described. The NH ₃ monitoring mechanism 6 includes an NH ₃ sensor 61 and monitors the generation of ammonia from the compost raw material CP being processed. In addition, when the generation of ammonia is detected by the NH ₃ sensor 61, for example, the signal is immediately sent to the spraying mechanism 7, and the oil O is automatically sprayed on the compost raw material CP in conjunction with the generation of ammonia. Is preferred. Further, when the NH ₃ sensor 61 detects or calculates the generation amount and concentration of ammonia, it is also possible to adjust the spray amount of the oil O and the like accordingly.

Next, the spreading mechanism 7 will be described. The spray mechanism 7 sprays oil O onto the compost raw material CP being processed. In this embodiment, as shown in FIG. 19, a reservoir 71 for storing the oil O and an end portion of the injection port of the oil O are provided. A nozzle 72, a delivery pipe 73 for transferring oil O from the reservoir 71 to the nozzle 72, a heater 74 provided in the vicinity of the injection port of the delivery pipe 73, and an electromagnetic valve 75 provided in the middle of the delivery pipe 73. It is made up of.
Of these, the heater 74 is responsible for, for example, heating the oil O that is in a solid state at room temperature and spraying it in a molten state, or even if the oil O is in a liquid state at room temperature, it is substantially the same temperature as the compost raw material CP. It is responsible for the action of spraying after heating. Incidentally, as the oil O that is solid at room temperature, cocoa butter, coconut oil, palm oil and the like are exemplified for vegetable oils and fats, butter, het, lard, net fat, kenne fat and the like are exemplified for animal fats and oils.

The solenoid valve 75 is a valve that causes the oil O to flow in the delivery pipe 73 or stops the flow. For example, when the NH ₃ sensor 61 detects the generation of ammonia, the solenoid valve 75 automatically sends the oil O from the delivery pipe 73. The operation mode in which is fed out and sprayed on the compost raw material CP is preferable.
In order to effectively reduce the ammonia odor, it is preferable to make the oil O into a fine mist and spray it uniformly on the compost raw material CP. It is desirable to operate the stirring mechanism 2. As a result, the mist-like oil O and the compost raw material CP can be mixed evenly.

Hereinafter, the composting method for suppressing the generation of the ammonia odor will be described while explaining the operation mode of the composting apparatus 1 described above.
(1) Inputting organic waste First, organic waste such as garbage is input into the treatment tank 11. As described above, the treatment tank 11 already contains inoculums as microbial materials and auxiliary materials such as sawdust, and the organic waste is decomposed by the action of the microorganisms. Of course, when the processing tank 11 is not filled with microorganisms or auxiliary materials, these are mixed with organic waste and put into the processing tank 11.

(2) Initial input of oil In the present invention, oil O such as lard is added together with the input of such organic waste. At this time, in actual composting, as described above, since it is difficult to determine the optimum addition amount at this stage, for example, it is limited to about 10% by weight (based on dry weight) of the total compost raw material CP. It is something to keep. Of course, when adding food residue such as tempura and fried foods, fish heads, etc. as raw garbage, the raw garbage already contains oil. it is conceivable that. Therefore, in such a case, it is not necessary to add the oil O separately from the garbage.

In addition, as the oil O added to the compost raw material CP, it is preferable to add animal oils or vegetable oils or fats that can suppress ammonia odor over the entire composting process as described above. It is also possible to mix and add.
If waste food oil is used as the oil O added to the compost raw material CP, the waste food oil can be recycled and the cost of composting can be reduced at once. In other words, 500,000 tons of waste food oil is generated annually in Japan, and as such, it is difficult to dispose of such waste oil. The cost reduction (reduction of running cost) of the composting method of the invention is achieved. In addition, since the waste food oil itself is difficult to process as described above, in some cases, a reverse charge is possible, and further cost reduction can be achieved.

(3) Substantive composting process First, the fan 31 of the aeration mechanism 3 is driven to send air (air) to the compost raw material CP in the processing tank 11 and supply oxygen to the microorganisms. Thereafter, when the microorganisms start to act, the organic matter of the compost raw material CP is gradually decomposed, and ammonia is generated depending on carbon dioxide, water, and conditions.
Meanwhile, within the apparatus main body 10 of the compost apparatus 1, during composting process, the generation of ammonia is constantly monitored by NH ₃ sensor 61 of NH ₃ monitoring mechanism 6. Of course, if the generation of ammonia is not observed even when composting progresses, it indicates that the initially added oil O is functioning, and when this becomes insufficient, the generation of ammonia is detected. For this reason, when the NH ₃ sensor 61 detects the generation of ammonia, it is preferable to output a signal, automatically open the electromagnetic valve 75, and spray the oil O from the tip of the nozzle 72. At the same time, the stirring mechanism 2 is operated to sufficiently mix the dispersed oil O and the compost raw material CP. In addition, since the heater 74 which heats the oil O is provided in the vicinity of the nozzle 72, this makes it possible to melt and spray the oil O that becomes solid at room temperature, for example, or to make the oil O substantially compost raw material CP. It becomes possible to spray after heating to the same temperature.
In this way, as shown in the above experimental results, the compost raw material CP to which the oil O has been added again mainly neutralizes the ammonia and suppresses the generation of ammonia odor throughout the composting process. To do.

  Next, an example of an apparatus that implements the composting method of the present invention as a relatively large-scale composting plant (denoted with 1A to distinguish it from the above-mentioned apparatus as a household garbage processing machine) will be described. To do. In this case, as organic waste, in addition to food waste, human and animal urine, feces and other human waste, sludge such as human waste treatment sludge and activated sludge for wastewater treatment in various factories, food products and shochu are produced. Animal and vegetable residues used as raw materials at the time can also be applied.

As shown in FIG. 20 as an example, the composting apparatus 1A as such a plant is formed by forming a treatment tank 11 in a standing state from a floor surface of a building covered with a roof or a wall surface. As an example, the processing tank 11 is formed to have a depth of 2 m, a width of 3 m, and a length of about 100 m. In addition, a vent pipe 35 is buried in the bottom of the treatment tank 11 and air is fed from here to supply oxygen to the microorganisms in the compost raw material CP. Reference numeral 36 in the figure denotes a pebble laid on the bottom of the processing tank 11 so as to cover the vent pipe 35. The vent pipe 35 is arranged so that the air discharge port faces downward, and a vent form in which the air discharged downward is directed upward while passing between the pebbles is preferable, thereby effectively blocking the air discharge port. This is what prevents it.
Furthermore, an agitation mechanism 7 that moves along the longitudinal direction of the tank is provided above the processing tank 11. The agitation mechanism 7 rotates the blade 22 having a large arm, for example, thereby compost raw material. The CP is agitated and splashed off, and the compost raw material CP is cut back.

In this case, the spray mechanism 7 for spraying the oil O to the compost raw material CP is preferably provided immediately before the stirring mechanism 2 (front side in the moving direction) and moved together with the stirring mechanism 2. This is because the compost raw material CP immediately after is sufficiently stirred and mixed.
Here, the heater 41 or the like for heating (holding) the compost raw material CP being processed to an appropriate temperature is not particularly provided here, but the heating / heat holding mechanism 4 for heating the air fed from the vent pipe 35 is provided. You can also. Here, the product temperature measuring mechanism 5 and the NH ₃ monitoring mechanism 6 are not particularly shown, but they are provided in the same manner as the above-mentioned household composting apparatus 1.

It is the table | surface which described the ratio of five types of compost raw materials (Run A-Run E) which varied the addition ratio of lard. It is the schematic which shows a composting experimental apparatus. It is a graph which shows a time-dependent change of the carbon dioxide gas generation amount in Run A and Run D. It is a graph which shows the lard decomposition rate (time-dependent change) of the carbon dioxide gas standard in Run D. It is a graph which shows the time-dependent change of the ammonia generation amount in Run A and Run D. It is a graph which shows the time-dependent change of pH in Run A and Run D. It is a graph which shows the measurement result of IR spectrum in 240 hours after composting of Run D. In Run A and Run D, it is a graph which compares and shows ammonia gas generation amount and ammonium ion abundance. It is a graph which shows the time-dependent change of the microorganism concentration in Run A and Run D. It is a graph which shows the lard decomposition rate (time-dependent change) of the carbon dioxide gas standard in Run B-Run E. It is a graph which shows the time-dependent change of the nitrogen volatilization rate in Run A-Run E. It is a graph which shows the nitrogen volatilization rate of the compost raw material which adjusted C / N ratio. It is a graph which shows the time-dependent change of the carbon dioxide generation amount in compost raw material Run A 'which does not add mineral oil, and compost raw material Run B' which added mineral oil. The graph (a) showing the change over time in the amount of ammonia gas generated in Run A ′ and Run B ′, and the time over time of the amount of ammonia gas generated in Run A and Run D with different lard addition ratios shown in FIG. It is the figure shown by comparing with the graph (b) which shows a change. It is a formula which shows an example of the molecular structure of animal oil, vegetable oil, and mineral oil. It is explanatory drawing which shows the decomposition process of a fatty acid (palmitic acid). It is the table | surface which described the fatty acid composition of vegetable oil and fat. It is the table | surface which described the fatty acid composition of animal fats and oils and vegetable oils. It is explanatory drawing which shows an example of the compost apparatus which actualized the composting method of this invention as a household garbage processing machine. It is a perspective view which shows the other Example of the apparatus which embodied the composting method of this invention as a comparatively large-scale composting plant.

Explanation of symbols

1 Composting equipment 1A Composting equipment (composting plant)
2 stirring mechanism 3 venting mechanism 4 heating insulation mechanism 5 dishes temperature measuring mechanism 6 NH ₃ surveillance 7 spray mechanism 10 apparatus main body 11 treatment tank 12 screen 12a small hole 21 rotating shaft 22 blades 31 fan 35 air pipe 36 pebbles 41 heater 51 temperature Sensor 61 NH ₃ sensor 71 Reservoir 72 Nozzle 73 Delivery pipe 74 Heater 75 Solenoid valve CP Compost raw material J1 Flow meter J2 CO ₂ trap J3 Bubbler J4 Rubber plug J5 Stainless screen J6 Minireactor J7 Tedlar bag J8 Incubator O Oil

Claims (4)

A method of composting compost raw materials mainly composed of organic waste such as garbage by microbial decomposition,
An appropriate amount of oil is added to the compost raw material to start composting,
In the composting process, the fatty acid produced from the oil undergoes decomposition from the carboxyl group side while repeatedly undergoing β-oxidation, and each time this β-oxidation, a short intermediate having two carbons is generated. Ammonia generated from the compost raw material is neutralized by the remaining intermediate product, and the generation of ammonia odor is suppressed.
In addition, during composting operation, processing is performed while monitoring the generation of ammonia, and when ammonia generation is detected, the generation of ammonia odor, which is characterized by the addition of oil to the compost raw material, is suppressed. Composting method.   2. The composting method according to claim 1, wherein waste food oil is applied as the oil added to the compost raw material.   The oil added to the compost raw material is added at a ratio of more than 10 wt% and less than 50 wt% on a dry weight basis with respect to all compost raw materials. Suppressed composting method. An apparatus that incorporates a treatment tank in the main body of the apparatus, inputs compost raw materials mainly composed of organic waste, ferments the compost raw materials by microbial decomposition, and composts.
The device is
A stirring mechanism for turning back compost raw materials in the treatment tank at an appropriate frequency;
In addition to providing a ventilation mechanism for supplying oxygen to the compost material in the treatment tank, a product temperature measurement mechanism for measuring the temperature of the compost material being processed,
An NH ₃ monitoring mechanism that monitors ammonia that may be generated from the composting material being processed;
It has at least a spraying mechanism for spraying oil onto compost raw materials housed in a treatment tank,
Further, the spraying mechanism is provided with a heater for appropriately heating the oil to be sprayed.