WO2015005070A1

WO2015005070A1 - Method for methane fermentation, straw material, and litter

Info

Publication number: WO2015005070A1
Application number: PCT/JP2014/065968
Authority: WO
Inventors: 政宏斉藤; 幸子中嶋; 智裕庄; 昭博中嶋; 智小倉
Original assignee: 三井造船株式会社
Priority date: 2013-07-11
Filing date: 2014-06-17
Publication date: 2015-01-15
Also published as: JP5567718B1; JP2015016440A

Abstract

The present invention addresses the problem of providing: a methane fermentation method which is excellent in terms of the possibility of resource recycling; and a hygienic straw material and litter. The problem is solved by: a method for methane fermentation which is characterized by subjecting straws that have been cut into sizes of 10-100 mm to methane fermentation in a fermentation broth and recovering a biogas and by recovering the fermented straws from the digestive juice to utilize the recovered straws as litter; and litter characterized by having been recovered from the digestive juice by the methane fermentation method. It is preferable that the problem be solved by conducting the methane fermentation at a temperature not lower than 50ºC.

Description

Methane fermentation method, firewood and bedding

The present invention relates to a methane fermentation method, a straw material and a litter, and more particularly, to a methane fermentation method excellent in the possibility of resource reuse, and a straw material and a litter that prevent corruption.

Conventionally, in order to obtain biogas by fermenting koji, it was necessary to pulverize to micron order (Patent Documents 1 and 2).

JP 2002-192191 A JP 2002-248448 A

藁 is used as a bedding to be laid in the breeding space for livestock.

藁 is a material that is relatively difficult to rot, but, for example, if it contains water, it will rot and will be unsanitary.

The present inventor has examined the use of a koji that has been previously fermented from the viewpoint of improving the spoilage resistance of the koji used as a bedding.

部分 By applying the fermentation treatment, the relatively perishable part contained in the cocoon is decomposed.

藁 The fermented rice cake is more difficult to rot, so it is hygienic when it is used as a bedding.

The present inventor has eagerly studied and studied in detail in the process leading to the invention described above, and thus has reached a further invention.

As described above, in order to ferment koji to obtain biogas, it has been conventionally necessary to pulverize to micron order. However, the present inventor actually kneaded koji fragments with a size of 10 mm to 100 mm. As a result of fermentation treatment, it was found that a sufficient amount of biogas could be recovered unexpectedly when fermentation was continued, although the start of biogas generation may be delayed somewhat immediately after the start of fermentation treatment.

When fermenting the koji crushed to micron order, the koji after the fermentation process is too fine, so it is difficult to recover it from the digestive juice. Even after recovery, it can be discarded or composted. It was used only for purposes and could not be used as the above-mentioned bedding.

If the cocoon fragments are 10 mm to 100 mm in size, a sufficient amount of biogas can be recovered by fermentation, and can be easily recovered from the digested liquid after the fermentation treatment, and is also suitably used as the above-mentioned bedding. It was found that the possibility of resource reuse was excellent.

Therefore, an object of the present invention is to provide a methane fermentation method, a sanitary dredging material and a bedding which are excellent in the possibility of resource reuse.

Further, other problems of the present invention will become apparent from the following description.

The above problems are solved by the following inventions.

1. Methane characterized in that cocoons crushed into 10 to 100 mm pieces are methane-fermented in a fermentation liquid to collect biogas, and the cocoons after fermentation are recovered from the digestive juice and used as a bedding. Fermentation method.

2. The methane fermentation method as described in 1 above, wherein the methane fermentation is performed at a temperature of 50 ° C or higher.

3. The methane fermentation method according to 1 or 2 above, wherein the straw is crushed by a rotary crusher having a chain as a rotating element.

4. The raw material containing the soot and organic waste is subjected to solid-liquid separation, and the soot collected in the solid phase after solid-liquid separation is crushed into 10 mm to 100 mm fragments and then mixed with the liquid phase after solid-liquid separation. The methane fermentation method according to any one of 1 to 3, wherein the methane fermentation is performed.

5. A litter collected from the digestive juice by the methane fermentation method according to any one of 1 to 4 above.

According to the present invention, it is possible to provide a methane fermentation method, a sanitary dredging material and a bedding which are excellent in the possibility of resource reuse.

Block diagram showing an example of a methane fermentation method according to the present invention Explanatory drawing showing the basic configuration of the rotary crusher The figure explaining an Example The figure which shows the result of the example

The methane fermentation method according to the present invention performs methane fermentation of koji crushed into pieces of 10 mm to 100 mm.

As a result, it is possible to recover a sufficient amount of biogas generated during fermentation, and the soot after the fermentation process (hereinafter sometimes referred to as “koji”) is more resistant to spoilage. Since it is hygienic, the effect of excellent resource reuse is achieved. Further, since this bran material is relatively large, it can be easily recovered from the digestive juice.

In the present invention, as the straw, for example, a dried stalk of a gramineous plant such as rice or wheat can be preferably used.

As described above, the straw material according to the present invention is obtained by subjecting straw crushed into 10 mm to 100 mm pieces to methane fermentation. Such a straw is hygienic and has an excellent possibility of being reused as a resource.

Since the litter according to the present invention is made of the above-mentioned cocoons, it is less susceptible to spoilage, and when used in a breeding space for livestock or the like, the effect of easily maintaining hygiene can be obtained.

用途 The use of the wood material according to the present invention is not limited to bedding. For example, clay walls with roofs, roofs, straw bales (straw bales architecture), straw bales, construction materials such as tatami mats, clothing materials such as grass straws, strawberries (Mino), straw hats, etc. It can be preferably used as container materials such as straws, ropes, dolls (scarecrows, etc.) or straw semi-paper raw materials, ash ash raw materials, etc.

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

FIG. 1 is a block diagram showing an example of a methane fermentation method according to the present invention.

In FIG. 1, 1 is a solid-liquid separation process, 2 is a crushing process, 3 is a mixing adjustment process, 4 is a methane fermentation process, and 5 is a dehydration process.

In the present invention, it is also preferable to use soot as a raw material by mixing it with organic waste, for example. The organic waste is not particularly limited, but preferred examples include animal manure (livestock manure) such as cows, pigs and horses, and garbage.

The raw material is subjected to the solid-liquid separation step 1 and is solid-liquid separated into a solid phase containing at least soot and a liquid phase.

The solid-liquid separation means is not particularly limited. For example, belt press dehydrator, screw press dehydrator, filter press dehydrator, belt press dehydrator, centrifugal dehydrator, multiple disk dehydrator, roller press dehydrator, wave press dehydrator A machine or the like can be preferably used.

The solid phase after solid-liquid separation is subjected to crushing step 2. On the other hand, the liquid phase after solid-liquid separation is supplied to the mixing adjustment step 3.

In the crushing step 2, the wrinkles contained in the raw material are crushed into 10 mm to 100 mm pieces, preferably 10 mm to 80 mm pieces, more preferably 10 mm to 50 mm pieces.

The crushing means is not particularly limited, and for example, a cutting machine or a rotary crusher described in detail later can be preferably used.

The raw material after the crushing process is supplied to the mixing adjustment step 3.

In mixing adjustment step 3, the liquid phase after solid-liquid separation described above and the raw material after crushing are mixed. The mixing ratio may be adjusted as necessary.

In the methane fermentation step 4, the raw material mixed as described above is subjected to methane fermentation using a methane fermentation tank.

According to the present invention, the straw material according to the present invention is produced in the digestive liquid (fermented liquid) by methane fermentation. The straw material preferably retains the shape before methane fermentation to some extent, and is preferably a 10 mm to 100 mm fragment, preferably a 10 mm to 80 mm fragment, more preferably a 10 mm to 50 mm fragment.

The temperature of methane fermentation is not particularly limited. For example, any type such as a so-called medium temperature type, high temperature type, and ultra high temperature type can be applied. In the present invention, fermentation is performed at a temperature of 50 ° C. or more. It is preferable. This makes it possible to sterilize miscellaneous bacteria and the like, so that the effect of further improving the hygiene of straw can be obtained. Although the upper limit of fermentation temperature is not specifically limited, It is preferable that it is 70 degrees C or less.

Also, it is preferable that methane fermentation is continued for preferably 5 days or longer, more preferably 10 days or longer, and most preferably 15 days or longer. The methane fermentation may be a batch type or a continuous type. When the methane fermentation is performed continuously, the average residence time in the fermenter corresponds to the duration of the methane fermentation.

In the present invention, it is also preferable to recover biogas generated with methane fermentation. According to the present invention, it is possible to generate a sufficient amount of biogas by using cocoons crushed into fragments of 10 mm to 100 mm.

The collected biogas, for example, is temporarily stored in a gas holder as necessary, and then purified by a purification facility, and used as power for a generator. It is also preferable to use the electric power obtained in this way for electric power sales.

The fermented digestive juice contains the firewood according to the present invention, and in the dehydration step 5, the dehydrated firewood is recovered from the digested liquid.

The dehydrating means is not particularly limited, and for example, those described above as the solid-liquid separating means can be used.

The digested liquid separated (dehydrated) from the straw is, for example, stored in the digested liquid storage tank, and then partially supplied to the mixing and adjusting step 3 and mixed with the raw material. In the present invention, the digestive juice can be preferably used as a fertilizer such as liquid fertilizer. In addition, the digestive juice can be added to feed or the like.

Next, the rotary crusher that is preferably used as the crushing means in the crushing step 2 will be described in detail.

FIG. 2 is an explanatory diagram showing the basic configuration of the rotary crusher.

2, 20 is a rotary crusher, 21 is a chamber, 22 is a rotating shaft, 23 is a rotating element, 24 is a mounting portion, and 25 is a motor.

The rotary crusher 20 has a rotating shaft 22 provided in the vicinity of the center of the bottom in a chamber 21 having an internal space, and a rotating element 23 formed of a chain here is attached to a mounting portion 24 formed at the tip of the rotating shaft 22. Is attached.

When the object to be processed (the solid phase separated in the above-described solid-liquid separation step 1 and including at least soot) is introduced into the chamber 21, it rotates and collides with the rotating element 23 on which centrifugal force is acting. To do. As a result, the straw is crushed and fragmented.

藁 By appropriately setting the operating conditions, it is possible to easily generate cocoons that are crushed into 10 mm to 100 mm pieces as objects to be processed.

Rotating element 23 is not limited to a chain, and may be a chain or a blade. The radius of rotation of the rotating element 23 (the length from the center of rotation to the outer peripheral end) is not particularly limited, but is preferably in the range of 50 cm to 200 cm.

As an example of operating conditions, the rotational speed of the rotating shaft is set to 800 to 1600 rpm, and the processing time is set to 25 to 40 seconds (total of charging time 10 seconds, crushing time 5 seconds to 20 seconds, and discharging time 10 seconds). It becomes possible to suitably produce cocoons crushed into 10 mm to 100 mm pieces, preferably 10 mm to 80 mm pieces, more preferably 10 mm to 50 mm pieces.

In one aspect of the present invention, “a crushed crushed piece of 10 mm to 100 mm” is, in other words, a crushed piece obtained by crushing using a rotary crusher under the above operating conditions. Can do.

In the above description, the case where the cocoon crushed into 10 mm to 100 mm pieces is subjected to methane fermentation together with cow dung or cow manure has been shown, but the present invention is not limited to this, and at least 10 mm to 100 mm pieces. It is sufficient that the crushed rice cake is subjected to methane fermentation. In the present invention, methane fermentation can be carried out by appropriately adding an additive to the kneaded crushed pieces of 10 to 100 mm.

In the present invention, a fragment of 10 mm to 100 mm refers to a piece whose longitudinal length falls within the range of 10 mm to 100 mm. In the present invention, it is sufficient that the cocoon satisfying at least the above conditions is subjected to methane fermentation. From the viewpoint of achieving the effects of the present invention more remarkably, the mixing ratio of “a bag that does not satisfy the above condition (less than 10 mm or more than 100 mm)” is preferably 5 wt. Part or less, more preferably 3 parts by weight or less, and most preferably 1 part by weight or less. When the mixing ratio of “soy that does not satisfy the above conditions” is high, it is also preferable to improve the ratio of “soy that satisfies the above conditions” by providing a sorting step for selecting “soys that satisfy the above conditions”. . Here, the case of defining the range of 10 mm to 100 mm has been described, but the description here is also applied to the case of defining another range.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to the examples.

1. Manufacture of cocoon fragments (crushing treatment)
<Amber fragment 1; 100 mm fragment>
A piece of wheat straw cut into 100 mm length with scissors was designated as cocoon piece 1 (FIG. 3).

<Swarf Fragment 2; 50 mm Fragment>
A piece of wheat straw cut into 50 mm length with scissors was designated as cocoon fragment 2 (FIG. 3).

<Bridge piece 3; Fragment of more than 1 mm to 20 mm>
The wheat straw was cut with scissors and then crushed with a household mixer, passed through a sieve having a diameter of 1 mm, and a piece on the sieve was taken as a piece 3 (FIG. 3).

<Fragment 4; Fragment of 1 mm or less>
In the production of the cocoon fragment 3, the sieving fragment was designated as cocoon fragment 4 (FIG. 3).

2. Methane fermentation <Test 1>
10 g of salmon fragment 1 (100 mm fragment) was mixed with 1.2 L of digestive juice (derived from cow dung) and subjected to methane fermentation under the conditions of 55 ° C., no pH control and manual stirring. FIG. 4 shows changes with time in the amount of biogas produced by methane fermentation.

<Test 2>
Methane fermentation was performed in the same manner as in Test 1 except that the cocoon fragment 1 was replaced with the cocoon fragment 2 (50 mm fragment) in Test 1. FIG. 4 shows changes with time in the amount of biogas produced by methane fermentation.

<Test 3>
Methane fermentation was carried out in the same manner as in Test 1 except that the cocoon fragment 1 was replaced with the cocoon fragment 3 (over 1 mm to 20 mm) in Test 1. FIG. 4 shows changes with time in the amount of biogas produced by methane fermentation.

<Test 4>
Methane fermentation was carried out in the same manner as in Test 1 except that the cocoon fragment 1 was replaced with the cocoon fragment 4 (fragment of 1 mm or less) in Test 1. FIG. 4 shows changes with time in the amount of biogas produced by methane fermentation.

<Test 5>
In Test 1, methane fermentation was carried out in the same manner as in Test 1 except that the koji fragment 1 was not used and only the digested liquid was used. FIG. 4 shows changes with time in the amount of biogas produced by methane fermentation.

3. Evaluation As shown in FIG. 4, in the case where the cocoon fragments having a size of 10 mm to 50 mm are subjected to fermentation treatment, the start of biogas generation may be delayed somewhat immediately after the start of fermentation treatment, but when fermentation is continued, It was found that a sufficient amount of biogas can be recovered. It was also found that when the cocoon fragments having a size of 100 mm were fermented, the amount of biogas generated in Test 4 (1 mm or less) was considerably close after 15 days.

It was also confirmed that the fermented koji substantially retained the shape before fermentation.

1: Solid-liquid separation process 2: Crushing process 20: Rotary crusher 21: Chamber 22: Rotating shaft 23: Rotating element 24: Mounting portion 25: Motor 3: Mixing adjustment process 4: Methane fermentation process 5: Dehydration process

Claims

Methane characterized in that cocoons crushed into 10 to 100 mm pieces are methane-fermented in a fermentation liquid to collect biogas, and the cocoons after fermentation are recovered from the digestive juice and used as a bedding. Fermentation method.
The methane fermentation method according to claim 1, wherein the methane fermentation is performed at a temperature of 50 ° C or higher.
The methane fermentation method according to claim 1 or 2, wherein the straw is crushed by a rotary crusher having a chain as a rotating element.
The raw material containing the soot and organic waste is subjected to solid-liquid separation, and the soot collected in the solid phase after solid-liquid separation is crushed into 10 mm to 100 mm fragments and then mixed with the liquid phase after solid-liquid separation. The methane fermentation method according to any one of claims 1 to 3, wherein the methane fermentation is performed.
A litter collected from the digestive juice by the methane fermentation method according to any one of claims 1 to 4.