JP2006150335A - Bad smell controlling material and method for controlling bad small of organic waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively control bad smell of organic waste such as livestock excrement, garbage, organic sludge and compost. <P>SOLUTION: This bad smell controlling material comprises an alkaline compound and an amorphous iron compound. A suitable amount of this bad smell controlling material is mixed in organic waste, which is then left as it is so that the bad smell can effectively be controlled at a humification step. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an odor control material and an organic waste odor control method.

  Conventionally, the odor emitted by organic matter such as animal and plant bodies, manure, raw garbage, organic sludge, compost, etc. is intense, and as rot progresses, the odor further increases and it has become a pollution problem, but it occurs in large quantities such as livestock farmers An effective measure for controlling the odor of organic waste has not been found.

  The inventors of the present application have studied materials that promote the humification of livestock excrement, and have found that humification can be promoted by simultaneously mixing an alkali compound and an iron compound into the livestock excrement. At the same time, it was discovered that by adding and mixing the humification promoting material to livestock excrement, intense odor is suppressed within a short time.

  The present invention is based on this technical discovery and aims to provide an odor suppressing material and an organic waste odor suppressing method capable of effectively suppressing the odor of organic waste.

  The odor control material of the invention of claim 1 is characterized by containing an alkali compound and an amorphous iron compound.

  According to a second aspect of the present invention, in the odor control material according to the first aspect, the alkali compound includes an alkali metal or an alkaline earth metal and exhibits alkalinity when water-solubilized. .

  According to a third aspect of the present invention, in the odor control material of the first aspect, the alkali compound is one of a carbonate, hydroxide or oxide of one or more of calcium, magnesium, potassium or sodium. It is characterized by including at least one.

  The invention of claim 4 is the odor control material according to claim 1, wherein the amorphous iron compound contains amorphous iron oxide or amorphous iron hydroxide, and crystalline iron oxide, crystalline iron hydroxide, A divalent or trivalent iron salt, an iron complex compound, iron ions, elemental iron, or a mixture of two or more thereof.

  A fifth aspect of the present invention is the odor suppressing material according to any one of the first to fourth aspects, wherein the alkali compound and the iron compound are supported or impregnated on a carrier having an inorganic or organic substance as a main substrate. .

  The organic waste odor control method of the invention of claim 6 adds the odor control material according to any one of claims 1 to 5 to the organic waste, thereby placing the organic waste. It is characterized by suppressing odor.

  The invention of claim 7 is the odor control method of claim 6, characterized in that the organic waste is animal manure, raw garbage, organic sludge, compost, or animal and plant bodies.

  According to the present invention, an odor suppressing material composed of an alkali compound and an iron compound is mixed with organic waste such as livestock excrement, raw garbage, organic sludge, and compost, so that the odor can be effectively obtained within a short time. Can be suppressed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[About humus]
“Humus” refers to “brown or dark non-black, which has a molecular weight of about tens of thousands to hundreds of thousands of newly synthesized (condensed or polymerized) bodies after being decomposed by microorganisms in the soil. It is said to be “crystalline organic matter”. Humus is an aggregate of various substances, and refers to a substance obtained by extracting organic substances with an alkaline substance such as sodium pyrophosphate or sodium hydroxide, as shown in FIG. This humic substance is a secondary high molecular compound with a strong black taste per unit carbon, and as the humification progresses, a secondary high molecular compound with a strong black taste per unit carbon is formed, and the color of the humus is changed. It turns yellow, reddish brown, and blackish brown. For this reason, the degree of blackening is used to indicate the degree of humification.

  The organic waste targeted for the odor control described in the present invention includes animal manure, raw garbage, organic sludge, compost and animal and plant bodies, and liquids containing these organic substances. Examples of the liquid containing organic matter include slurry substances such as manure slurry, and squeezed juice from which excess water exudes during compost production.

  In order to evaluate the progress of humification, humification degree, humic acid content and morphological analysis of humic acid were performed. The sample was prepared by air-drying for 48 hours or more in a dryer at 105 ° C., and the dried sample was pulverized.

  The humic acid content was measured according to “Testing Method for Peat and Humic Acid Material” established by the Ministry of Agriculture, Forestry and Fisheries.

  About the degree of humification, the light absorbency in wavelength 550nm of the sodium pyrophosphate extract was measured according to the method used as a decomposition index of peat.

In humic acid morphological analysis, humus is extracted from a sample using sodium hydroxide solution or sodium pyrophosphate / sodium hydroxide mixture, then the extract is acidified to separate humic acid (precipitate) and fulvic acid. About the solution which dissolved the obtained humic acid again in the sodium hydroxide solution, the organic carbon content and the light absorbency in wavelength 400 and 600 nm were measured. Based on the classification method of humic acid, a color tone coefficient (Δlog K) and a relative chromaticity (RF) were calculated. The color tone coefficient (ΔlogK) is obtained as shown in the following equation from the difference between the absorbance at a wavelength of 400 nm and the absorbance at a wavelength of 600 nm.
ΔlogK = ΔlogK ₄₀₀ −ΔlogK ₆₀₀
(However, K ₄₀₀ and K ₆₀₀ indicate the absorbance at wavelengths of 400 nm and 600 nm, respectively.)
RF can be determined from the absorbance of the humic acid solution at a wavelength of 600 nm and the amount of KMnO ₄ consumed or the organic carbon concentration.

  FIG. 2 shows the degree of progress of humification using the hue coefficient (ΔlogK) and relative chromaticity (RF) as indices. Humic acid can be classified by the correlation between RF and ΔlogK. Region A is a high humus degree region, region Rp is a low humus degree region, and B and P are intermediate regions. In general, as humification progresses (blackening and stabilization of humic acid), ΔlogK decreases and the RF value increases. When this method is applied to soil, if Δlog K is 0.7 or less and the RF value is 80 or more, it is classified as A-type humic acid, and humic acid that is very advanced in humification included in black soil such as black soil means.

  As shown in FIG. 3, the organic waste before humification, that is, the non-humic substance, is humated through the Rp-PA route in the humification process, or the Rp-BA route. Then humification progresses.

  In the form of humic acid, free humic acid is extracted by extraction with sodium hydroxide, and free humic acid is extracted by extraction with sodium pyrophosphate, and combined humus that forms a complex with aluminum hydroxide, iron oxide, etc. The acid can be extracted.

[Humification promotion material and odor control material]
In order to produce such a humic substance, it takes a long time to wait for decomposition of organic substances in nature. However, the present inventors have made paper sludge carbide (PSC) obtained by high-temperature treatment of paper sludge, which is wastewater treatment sludge of a recycled paper manufacturing plant, as a composting material for livestock excrement discharged from a free stall barn. The product name Blacklight (registered trademark, manufactured by Doei Paper Industry Co., Ltd.) is added and mixed, and the deposit is thoroughly stirred and re-stacked at regular intervals, so-called turning work is performed, and the property change is observed. As a result, it was found that the odor was remarkably reduced immediately after PSC mixing. In addition, the temperature of livestock excrement gradually increased after deposition, and the same temperature increase tendency was observed after the second turnover. In addition, it was observed that the temperature was higher as it was closer to the bottom of the deposit, and that an exothermic reaction occurred even at a high moisture content and close to the reduced state. Along with this, it was also discovered that the intense odor generated by organic waste due to the addition and mixing of PSC is suppressed within a short time.

  From this phenomenon, the inventors of the present application have brought about an effective humification promoting action against organic waste such as livestock excretion, and an odor suppressing action, as some components contained in PSC. Assuming that this is the case, the components contained in PSC were analyzed, and substances showing humification promoting action and odor suppressing action were identified.

The analysis results of the components contained in PSC were as shown in Table 1 of FIG. From the elemental analysis results, it was found that the PSC contained 15 to 20% by weight of calcium oxide as an alkali compound and 7 to 20% of iron oxide as an iron compound when converted to an oxide. Furthermore, calcium in PSC is mainly composed of fine calcium carbonate that has been used as a filler for used paper raw materials, and only a small part is converted to quick lime during carbonization. The iron compound is derived from polyferric sulfate ([Fe ₂ (OH) _n (SO ₄ ) _{3-n / 2} )] _m , which was used as an inorganic flocculant in the wastewater treatment process. Half of the amount is amorphous iron. It also contains iron oxide and elemental iron.

  It is presumed that the alkali compound and the iron compound act as follows in the humification process described above. Alkaline compounds elute humic substances and polyphenols (primary humic acid-like substances) such as tannin and lignin contained in organic waste. Next, the eluted humic substances, polyphenols, and organic acids present in the organic waste are catalyzed by iron compounds to cause chemical reactions such as polymerization and condensation. In this chemical reaction, metals such as iron, calcium, and magnesium contained in the iron compound and the alkali compound act as a cross-linking substance when generating humic substances. Moreover, these series of reactions are further promoted by increasing the temperature, but the iron compound also contributes to the temperature increasing action. In other words, alkali compounds and iron compounds, particularly iron oxide, supply oxygen to suppress the reduced state in organic waste. The oxygen supplied here accelerates the oxidation reaction and aerobic microbial reaction of substances in organic waste, and generates heat, while the alkali compound generates heat by neutralizing with acidic substances contained in organic waste. To do. These calorific values are very small, but due to the large amount of organic waste such as livestock excrement deposits, the surface becomes a powerful heat insulating material and enhances the livestock heat effect. Humidification is promoted by the above exothermic reaction.

  The following mechanism is assumed for the above exothermic reaction.

  In slurry-like manure and high-water manure, oxygen supply from the atmosphere is extremely low, and dissolved oxygen in the manure is consumed by microbial reactions, etc., so aerobic fermentation is unlikely to occur. . However, when amorphous iron oxide or crystalline iron oxide is added as a humus accelerator, oxygen is supplied into the fecal urine liquid by these iron oxide compounds, It is presumed to cause a metabolic reaction of microorganisms.

  That is, when the dissolved oxygen concentration in manure is low, iron oxide releases oxygen by the catalytic action of an enzyme produced by a part of the microorganism and is reduced to bivalent. The released oxygen is used for aerobic microbial degradation of cellulose in manure and easily decomposable organic matter, and carbon dioxide, water, and heat are obtained. On the other hand, divalent iron ions reduced by releasing oxygen (reducible iron ions) combine with sulfur-based odorous substances such as hydrogen sulfide and methyl mercaptan to suppress the generation of bad odors, and this divalent iron ion Forms a stable complex with humic substances and promotes the production of secondary humic acid and the progress of humification.

  When this mechanism is applied to liquids containing water-soluble humic substances such as manure slurry and compost exudate, divalent or trivalent iron ions form water-soluble humic acid and stable humic acid. The part is precipitated.

  The mechanism of the odor control effect as well as the humification effect was analyzed. This is shown in FIG.

    (I) An alkali compound neutralizes and inactivates odorous substances such as volatile fatty acids (VFA) which are odorous components of organic waste.

    (Ii) The iron compound is inactivated by causing a chemical reaction (combination and adsorption) with a sulfur-based compound that causes odor such as methyl mercaptan and hydrogen sulfide.

    (Iii) The iron compound becomes divalent iron in the reduced state and is stabilized by forming a complex with the VFA and the sulfur (S) compound. It is inactivated by combining with a sulfur compound and precipitation.

    (Iv) Alkaline compounds and iron compounds promote the formation of humic substances. The produced humic substance adsorbs ammonia, amine-based odor and the like by its function and suppresses the generation of odor.

    (V) Odor is suppressed by incorporating odor generating components such as VFA and sulfur compounds, ammonia and amines into the humic substance in the process of humic substance generation.

  From such considerations, substances useful as humification promoters and odor control materials are mainly composed of alkali compounds and iron compounds, and alkali compounds contain alkali metals or alkaline earth metals, and are water-soluble. A compound which shows alkalinity when it is converted, and preferably contains at least one of carbonate, hydroxide or oxide of one or more of calcium, magnesium, potassium and sodium, The compound includes an amorphous iron compound, crystalline iron oxide, crystalline iron hydroxide, divalent or trivalent iron salt, iron complex compound, iron ion, elemental iron alone, or their A mixture of two or more types is preferred.

  The odor-suppressing material of the present invention may be a material in which an alkali compound and an iron compound are supported or impregnated on a carrier having an inorganic or organic substance as a main substrate. In addition, the odor-suppressing material of the present invention may be used by drying, firing, and carbonizing what is supported or impregnated on the carrier. Examples of the inorganic material include zeolite and clay, and examples of the organic material include wood chips and sawdust.

  The addition amount of the odor control material is effective even if it is a small amount, for example, 1 wt%, with respect to the organic waste, but a larger amount is preferable.

  Although the odor suppression of the present invention can be achieved by an odor suppression material containing only an iron compound, the odor suppression material described in the present invention preferably contains not only an iron compound but also an alkali compound.

[Experimental example 1] (dairy cow manure composting test)
Containing 25 to 20% of livestock excreta with a moisture content of 85% discharged from a free stall barn that performs defecation work twice a day, it contains 10 to 20% dry weight ratio of calcium carbonate as an alkali compound as composting material. The humification promoting material and odor control material containing 5 to 20% of the dry weight ratio of the iron compound was added at 2% and 500 kg with respect to the water content of the livestock excrement and mixed well. Half of the iron compound was in an amorphous form. A control group was set using excreta equivalent to the test group. After mixing the odor-suppressing material, a so-called reversing operation was carried out, in which thorough stirring was repeated once every 30 days.

  Immediately after mixing of the odor control material, the odor was remarkably reduced. This is because the odorous components such as methyl mercaptan and sulfur sulfide, and volatile fatty acid odors such as butyric acid, isovaleric acid, and propionic acid are neutralized by the alkali compounds contained in the humification promoter. In addition, it became inactive by being combined with humic substances by the catalytic action of the iron compound.

  At the temperature at the time of deposition (depth of 50 cm from the surface), in the test section, the temperature gradually increased after the deposition, and reached about 37 ° C. at the first turning after 30 days. On the other hand, there was almost no temperature increase in the control group. The same tendency was observed at the second turnover after 60 days. In the test section, the temperature reached about 40 ° C.

  In addition, the temperature is higher near the bottom of the deposit, and since the exothermic reaction occurs even in a place where the moisture content is high and close to the reduced state, iron contained in the humification promoting material and odor control material, particularly the iron oxide component It is considered that the oxygen supply caused by oxygen induces heat generation due to oxidation reaction and enhances the activity of aerobic microorganisms. Although these calorific values are very small, it is thought that the effect of animal heat was high because the surface of the animal excrement deposits became a powerful heat insulating material due to the large amount of accumulation.

  In the third turn-back after 90 days, the temperature rise was low but rather tended to decline. This is considered to be due to the consumption of alkali compounds and iron compounds necessary for heat generation.

[Experimental example 2] (dairy cow manure composting test)
In a free stall barn where defecation work is performed twice a day, 2% of the total excreta excretion assumed to be 60 kg / day / head after daily defecation work in the morning and evening, 1.2 kg / day / head The corresponding PSC was sprayed. The sprayed PSC was agitated by the cows in the barn and mixed with manure. PSC was sprayed in the barn every week.

  By the above procedure, 25 t of cow manure containing 2% by weight of PSC was deposited on a compost having a structure having a concrete impermeable floor and a roof. The water content at this time was 79.3%. At the same time, a control group in which the same amount of cow manure without PSC was deposited was set. The water content in the control group was 83.7%.

  The management was carried out once every month, and the temperature change during the deposition period and the state of odor at the time of switching were observed. The survey dates for temperature change and odor status were August 10, September 10, October 13, and November 15. The change in odor is shown in FIG. 9, and the change in temperature is shown in FIG. The total odor was measured using an XP329III odor sensor manufactured by New Cosmos Electric. And the surface odor shows the odor at the height of 1 cm of the deposition surface, and the inside shows the odor at a depth of 30 cm. Further, hydrogen sulfide, methyl mercaptan, and ammonia were measured using a detector tube manufactured by Gastec.

  The progress of humification promotion is as shown in the sample photographs of 1 to 3 months after deposition in FIGS. In these photographs, the sample on the left is the sample in the test group (PSC group), and the sample on the right is the sample in the control group. As can be seen from FIGS. 6 to 8, the PSC section (left side) showed high blackness in 1 to 3 months after deposition. From the second month after the deposition, coarse organic matter such as wheat straw became soft and decomposed. Moreover, it became a dense deposition state with few air layers with the softening of coarse organic matter.

  The results of temperature change and odor status of dairy manure composting test are discussed below.

  At the time of the first survey in the first month of the test (August 10), the temperature in the PSC group was as high as 43 ° C, and the temperature difference was as high as 33 ° C in the control group. Was about 1.5 times higher. Sensoryally, the PSC group felt a strong ammonia odor, while the control group felt a strong odor of manure. This is because the PSC section shows an increase in temperature due to fermentation, which is presumably due to the high volatilization amount of ammonia.

  In the survey on September 10, we were able to realize that the odor in the PSC area was clearly suppressed during the turnover work. The measurement result by the odor sensor was also a numerical value less than half of the PSC group 404 with respect to the control group 933 by the odor inside the deposit. In the measurement of hydrogen sulfide using a detector tube, a slight amount was detected in the control group. Ammonia was high in the PSC section, but this is thought to be due to the generation and volatilization of ammonia when the readily decomposable organic matter is mineralized by fermentation.

  In the survey on October 13, the temperatures of the PSC group and the control group were reversed, and the control group showed a higher temperature (37 ° C.). Sensoryally, almost no unpleasant manure odor was felt in the PSC group, but the control group released a remarkable manure odor, and the stimulated odor of ammonia became stronger.

  In the survey on November 15th, both the PSC and control plots were affected by a decrease in fermentation temperature and a decrease in outside air temperature, and volatile odors were hardly felt. Particularly in the PSC zone, the atmosphere of the compost board and the odor on the surface of the deposit were almost odorless. The internal odor is about the same as the odor measured on October 13 in the control group, whereas the PSC group is almost halved from the measured value on October 13, and the odor is about 1/3 of the control group. Declined. Anaerobic fermentation has begun inside the control zone, and the odor of the gas generated from the inside was extremely high at 700 to 800. The hydrogen sulfide odor in the control group was 8 ppm, 10 times the value measured on October 13. Hydrogen sulfide was not detected in the PSC zone. Ammonia was lower in both test zones than on the October 13 survey. This is considered due to a decrease in fermentation temperature and a decrease in outside air temperature.

  It is confirmed that composting and humification in both test plots are clearly progressing in the PSC zone and blackened due to the progress of humification (see FIGS. 6 to 8). In the cultivation of young plants (Komatsuna) that showed the growth inhibitory properties of compost plants, germination was observed with a low probability in manure in the PSC section, suggesting suppression of growth inhibitory factors by the progress of humification.

  The feces and urine tested in this test had a very high water content of 80%, and it has been reported that composting has hardly progressed as seen in the control plot. However, it was very interesting from the viewpoint of the future treatment or effective use of manure that the composting process was improved by the addition of PSC.

[Experiment 3] (Pig manure composting test)
PSC was mixed well with fresh pig dung at a ratio of 2% by weight. In this state, since the water content is high, fluidity is high and deposition is impossible. Therefore, it is mixed with the fir shell at a volume ratio of 2: 1 every week, adjusted to a depositable hardness, and then put into the deposition pit. It was. For administrative purposes, pits are moved every month, but this was turned back. The moisture content of the compost after deposition was about 75-80%. At the same time, a control group in which PSC was not mixed was set. The deposition date was September 12, and the survey dates were September 15, October 9, November 6, December 4, and January 17. The measured change in odor is shown in FIG. 11, and the change in temperature is shown in FIG.

  The results of the temperature change and odor status of the pig manure composting test are discussed below.

  Pig feces had a stronger irritating odor than dairy cows, and the odor sensor data immediately after deposition showed a value 7 to 10 times that of dairy cows. In the survey on September 15th, the third day after deposition, both test areas gave off a significant odor. However, in the odor sensor data, the odor in the PSC area was suppressed by about 30% compared to the odor in the control area. It was. Further, in the PSC group, sulfur-based odors such as methyl mercaptan and hydrogen sulfide detected at a high concentration in the control group were not detected, and the odor in the sensory test was also different from the sulfur-based odor. Ammonia was 25 ppm in the control group compared to 100 ppm in the PSC group. The compost temperature around the survey date is higher in the PSC group than in the control group, and it is considered that the compost temperature has a considerable influence on the progress of composting.

  In the survey on October 9, the internal odor decreased by about 60% compared to immediately after deposition. After the first turnover, the temperature rose significantly in both test sections. In particular, in the PSC group, the temperature rose to 65 ° C., which was 6 to 7 ° C. higher than that in the control group. On the other hand, ammonia is higher in the control zone where the temperature is lower, indicating a difference in the reaction process during composting.

  In the survey on November 6, the compost temperature in the PSC group exceeded 70 ° C, and the temperature difference from the control group was 10 ° C or more. Odor decreased at a constant rate in both test plots, but for ammonia, the control plot exceeded the detection limit of 200 ppm, whereas the PSC plot compared with the October 9 survey. Slightly decreased.

  In the December 4 survey, the compost temperature in the PSC area almost exceeded the peak, and the temperature began to drop. However, it rose again to 70 ° C or higher after switching. At this time, the odor in the PSC group was not sensed in terms of feces and urine, but only the stimulating odor of ammonia was strongly felt. The ammonia concentration in the PSC group was further reduced to 100 ppm, while the concentration in the control group was still 200 ppm or more.

  According to the survey on January 17th, the fourth month after deposition, the PSC ward became compost that was almost fully ripe. The ammonia concentration was as low as 36 ppm, which was a symmetric result with the control group exceeding 200 ppm. The internal odor data from the odor sensor dropped to 260, approaching the atmosphere of a livestock barn. Even in the control plot, there was a slowdown in the increase in compost temperature.

  The analysis result of compost as of January 17 is shown in FIG. Due to the temperature difference between the two test sections, the PSC group showed a marked decrease in moisture compared to the control group, and there was no stickiness even when touching the compost. As a result of the nitrogen morphological analysis, nitrate nitrogen in the PSC section was detected extremely high. On the other hand, the temperature of the control group also rose to 60 ° C. or more, and it can be said that the fermentation was good from the viewpoint of conventional compost production. However, the compost produced in both test areas was quite different as seen in the results of the above analysis of compost (FIG. 13).

[Experimental example 4] (chicken manure composting test)
PSC was added to fresh chicken manure 11.6 t at a ratio of 2.5% by weight and mixed well. A control group in which PSC was not mixed was set using the same chicken dung. Management was in accordance with common practice, and in principle, no reversal was performed, and reversal was performed as necessary. The accumulation date of chicken dung was September 12, and the survey dates were September 16, October 9, November 6, December 4, and January 17. The measured change in odor is shown in FIG.

  Unlike the case of cow dung and pig dung, the compost temperature did not increase in the PSC group, and the temperature increased immediately after deposition in the control group. The compost temperature in both test groups tended to decrease during the test period. It was. Although it turned over once on December 13, the temperature did not rise again in both test sections.

  From the odor measurement results, the odor suppression effect of hydrogen sulfide and methyl mercaptan immediately after deposition (September 16) is remarkable. On the other hand, the total odor measurement result by the odor sensor is high in the PSC section, and it is estimated that a remarkable odor suppression reaction occurs immediately after the PSC mixing.

  As a result of odor measurement, the value of the odor sensor in the PSC group throughout the test period was about ½ of that in the control group. In the control group, hydrogen sulfide was generated in 3 months after deposition, but in the PSC group, it was suppressed to a low level. As for ammonia, the value in the control group at the beginning of deposition exceeded the value in the PSC group, but thereafter there was no significant difference between the two test sections.

  The chicken manure used in Experimental Example 4 contained almost no litter, had a relatively low water content, and had a high consistency characteristic of chicken manure. The charged PSC was well mixed, but it is thought that the odor suppression reaction was restricted by absorbing excess water in the chicken dung and solidifying the chicken dung itself.

From the results of the above Experimental Examples 1 to 4, it was recognized that PSC has a function of remarkably suppressing the malodor of livestock manure.

FIG. 1 is an explanatory view of general humus separation. FIG. 2 is an explanatory diagram of the degree of progress of humification using the hue coefficient (ΔlogK) and relative chromaticity (RF) as indices. FIG. 3 is an explanatory diagram of the humification process. FIG. 4 is Table 1 showing the results of PSC analysis. FIG. 5 is an explanatory diagram of the humification promoting action and the odor inhibiting action by the humification promoting and odor suppressing material of the present invention. FIG. 6 is a contrast photograph of a humus sample (left side) and a non-humus sample (right side) one month after the start of the humus experiment in Experimental Example 2. FIG. 7 is a contrast photograph of a humus sample (left side) and a non-humus sample (right side) two months after the start of the humification experiment in Experimental Example 2 of the present invention. FIG. 8 is a comparison photograph of a humus sample (left side) and a non-humus sample (right side) 3 months after the start of the humus experiment in Experimental Example 2 of the present invention. FIG. 9 is a table showing odor measurement results in Experimental Example 2 (dairy manure composting test) of the present invention. FIG. 10 is a graph showing temperature changes in Experimental Example 2 (dairy cow manure composting test) of the present invention. FIG. 11 is a table showing odor measurement results in Experimental Example 3 (pig manure composting test) of the present invention. FIG. 12 is a graph showing temperature changes in Experimental Example 3 (dairy cow manure composting test) of the present invention. FIG. 13 is a table showing the analysis results of compost in Experimental Example 3 (dairy cow manure composting test) of the present invention. FIG. 14 is a table showing odor measurement results in Experimental Example 4 (chicken manure composting test) of the present invention.

Claims (7)

  An odor suppressing material comprising an alkali compound and an amorphous iron compound.   The odor suppressing material according to claim 1, wherein the alkali compound includes an alkali metal or an alkaline earth metal and exhibits alkalinity when water-solubilized.   2. The odor control material according to claim 1, wherein the alkali compound includes at least one of a carbonate, a hydroxide, and an oxide of any one or more of calcium, magnesium, potassium, and sodium. .   The amorphous iron compound includes amorphous iron oxide or amorphous iron hydroxide, crystalline iron oxide, crystalline iron hydroxide, divalent or trivalent iron salt, iron complex compound, iron ion, The odor-suppressing material according to claim 1, wherein the odor-suppressing material is any one of elemental irons or a mixture of two or more of them.   The odor suppressing material according to any one of claims 1 to 4, wherein the alkali compound and the amorphous iron compound are supported or impregnated on a carrier mainly composed of an inorganic substance or an organic substance.   The odor control of the organic waste characterized by suppressing the odor of the organic waste by adding the odor control material according to any one of claims 1 to 5 to the organic waste. Method.   The organic waste odor control method according to claim 6, wherein the organic waste is animal manure, raw garbage, organic sludge, compost, or a plant and animal remains.