JPS5918352B2 - Processing method for processed materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for treating livestock manure, sewage sludge, etc. , sewage sludge generated from sewage treatment plants, other fish dregs, poultry carcasses, frozen fields, various organic industrial wastes, etc., or composting. This is a processing method and apparatus related to the case.

It is desirable that the above-mentioned various wastes, mainly livestock manure, be processed into a reusable form and reused as fertilizer, feed, etc.

For this purpose, composting is the most preferable treatment, and as a result of this treatment, the material to be treated, such as livestock manure, becomes compost, which can be reused as fertilizer.

When composting livestock manure, etc., it is necessary to maintain the material to be treated in appropriate aerobic environmental conditions, and the factors include temperature, moisture content of the material, air volume, oxygen content, and processing time. is important.

In other words, if we are to describe the general form of the composting method, first of all,
To start the composting reaction, the material to be treated must have an appropriate moisture content (
This is adjusted to approximately 20-70% by weight), then put into a reaction vessel, and in most cases forced air is introduced to bring in oxygen to make it aerobic. As a result of a naturally occurring aerobic microbial reaction, the treated If the temperature of the object increases and the reaction is good, 50
℃ to 80℃, and desired compost can be obtained by maintaining this high temperature for a long time (often 24 to 48 hours).

As mentioned above, the composting reaction is a type of oxidation reaction that uses organic matter in livestock manure as fuel and proceeds at a relatively low temperature with the intervention of aerobic microorganisms. Therefore, the success or failure of the reaction depends on appropriate control of the various factors mentioned above. The most important thing in practical terms is how to feed sufficient air as evenly as possible to all the objects to be treated in the reaction vessel, and how to minimize the energy required to do so. is the problem.

All conventional composting methods have a major drawback in this respect. For example, as shown in FIG. When livestock manure 2 adjusted to a certain level is directly thrown in and air is blown from below with a blower 4, etc., the material to be treated presents a large resistance to the air flow, and therefore the horsepower of the blower must be increased, and even then, As shown by the arrow, air passes only through the area of the object to be processed that is in contact with the reaction vessel wall, and only this area has good ventilation, so the area around the center often has insufficient ventilation and is inconvenient. This leads to various disadvantages such as:

First, in this conventional method, the composting reaction does not proceed sufficiently and the temperature rise becomes slow.

Second, the reactants generated as a result of internal anaerobic reactions are dangerous as fertilizers.

Third, the energy required for ventilation is large, which increases running costs.

The present invention eliminates these drawbacks of conventional composting methods, and involves adjusting the moisture content of the material to be treated at an appropriate level prior to the reaction, and then molding the material into pellets in the shape of a round bar or the like of an appropriate size. The method is characterized in that it is processed so that air is evenly supplied to the object by forced air or natural air.

Thus, in the present invention, since the object to be treated is formed into pellets in the shape of a round rod, even when the objects are packed in a reaction container, there is always a sufficient gap between one pellet and another pellet. Since air flows through it, a good aerobic condition is created throughout the reaction vessel, so that a uniform and sufficient composting reaction occurs throughout the vessel, and the temperature rises quickly and becomes high. The part where anaerobic reactions occur is virtually eliminated, and all of it becomes good fertilizer, and the energy required for ventilation is extremely low, reducing running costs.

The overall reaction time is also shortened.

Next, details of the present invention will be described based on examples.

Figures 2a and 2b show the most basic embodiment of the present invention,
Figure a is a side sectional view of the reaction vessel 1, and the figure is an enlarged perspective view of the object to be treated when it is formed into a round bar-shaped pellet.

In the figure, the reaction vessel wall 1 is made of asbestos for insulation.
(or plastic reinforced with eta-knit, FRP, or glass fiber can also be used) and is further supported by an external reinforcing material (steel material here), which is not shown in the drawings.

(In low-temperature regions, insulation materials such as foam stay roll boards may be applied to the outside.

) At the bottom of the reaction vessel, it is possible to apply meshes 3 at intervals of about 1cn1 to prevent pellets from falling, and to further reinforce the meshes with steel reinforcing material.

The object to be treated 5' formed into pellets is put into the thus formed place to fill the reaction vessel 1, and then air is blown from the bottom of the reaction vessel 1 by the blower 4.

Here, the material to be treated 5' is egg-laying chicken manure, which has been previously composted and dried using a separate method, and then powdered dry compost from egg-laying chickens is mixed in a mixer until the moisture content is 50%. After adjustment, it was molded into round rod-shaped pellets with a diameter of 30 mm using a screw press type extrusion molding machine (pellet molding machine), but the uniform length of the pellets was 7 an.
This is then put into the reaction vessel mentioned above.

The size of the reaction container is 3 m at the entrance, 3 m at the depth, and 4.5 m at the height.
m, and was filled with pellets to a height of 3 m from the bottom.

As soon as air was started to be blown using a blower, the temperature of the object to be treated increased, reaching 80° C. in two days.

As the air blowing was continued, the temperature remained steady for a while, then gradually decreased and reached room temperature after two days.

After this, the pellets were taken out and found to be good compost with a moisture content of about 30%, and the inside of the reaction vessel also underwent an aerobic reaction evenly, indicating good conditions.

Figure 2 is a model showing how the pellets 5' in the reaction vessel are clogged, and air easily flows through the gaps between the pellets as shown by the arrows.

FIG. 3a shows a reaction vessel according to another embodiment of the present invention, in which a plurality of rotary shafts 6 and ratchet wheels 7 are shown at the bottom of the reaction vessel 1 as a device for taking out pellets after the reaction. It was set up like this.

In this way, a plurality of thick rotating shafts 6 supported by bearings at both ends are passed through the bottom of the reaction vessel 1 parallel to each other, and the rotating shafts 6 are
A plurality of ratchet wheels 7 are attached as shown in Figure 3.

The ratchet wheels 7 are engaged with each other with a small gap, so that the pellets 5' do not fall during processing in the reaction vessel 1.

Now, in order to take out the pellets 5', attach gears (not shown) that mesh with each other to one end of all the rotating shafts 6, and rotate one of them with an external driving force. Adjacent ratchet wheels rotate in opposite directions, and ratchet wheel 7
As a result, the pellets 51 are scraped off and fall down through the gap between the rotating shafts 6.

Although the ratchet wheel 7 has four pawls in the figure, there is no need to limit the number of pawls.

It is preferable that such a combination of the rotating shaft and the mold wheel be spread over the entire bottom surface of the reaction vessel, but it may be formed only on a part of the lower bottom portion.

Fig. 4 is a processing system diagram of one embodiment of the present invention. Taking egg-laying chicken manure as an example, most of it is semi-liquid with a water content of nearly 90%. It is stored in a tank 8 at room temperature and stirred with a pump 9 to make it homogeneous. After converting to
(a set of screws) at a constant rate.

Dry compost 12, which has been pulverized in advance, is fed into the mixer 11 from one side and mixed to a moisture content of 50%.

This mixture 13 is transferred to the hopper 14' of the pellet molding machine 14.
from one side using a screw press to make multiple diameters of 30 mm.
The mixture was pushed toward the other end of the cap which had circular holes, and the mixture was extruded through the holes into pellets 5'.

The pellets are put into the reaction container 1 which has a plurality of mold wheels at the bottom by a conveyor 15, and are made into compost by ventilation by the blower 4 from the bottom of the reaction container. (not shown), the compost is fed into the pellet forming machine 14 again, and after being pelletized, it is transferred to the reaction vessel 1.
', and a blower with one heater 4'
Hot air was blown to make dry compost with a moisture content of 18%.

Further, this is scraped off by rotating the mold wheel at the bottom of the dryer 1', and a portion is deposited as a product 11, and a portion is crushed by a hammer mill 18 to a diameter of approximately 0.
After grinding into powder of 5 mm or less, it is stored in a silo 19 and used for adjusting the moisture content of raw manure.

The embodiments of the present invention are wide-ranging; for example, in addition to the configuration shown in FIG. 4, the initial composting is performed by pelletizing,
The subsequent drying reaction may be carried out in the form of powder or coarse particles, or the reaction vessel 1. Instead of using two separate dryers 1', they are used as one container, and after the material to be treated is pelletized and the composting reaction is first completed, the drying reaction is started by strongly blowing warm air or room temperature air. , can also produce the final product.

Or, in a reaction vessel, it is turned into pellets and basically composted.

Only the oxidation reaction is carried out, and then removed from there and placed in a simple facility, such as a vinyl greenhouse, plastic greenhouse, glass greenhouse, or ordinary compost house, without forced ventilation (or without forced ventilation; If the compost passes through a drying facility before entering the composting reaction tank, the compost also has a deodorizing effect, which prevents the generation of bad odors from the drying facility.

Alternatively, as another method, the silo 19 containing the dry powder in the flow sheet of FIG. 4, the mixer 11, and the pellet molding machine 14 are combined into one unit, and
Often such units are mobile and have a separate third unit.
After installing a plurality of reaction vessels as shown in Figure a, and making sure that these reaction vessels can be ventilated from below, operate the unit to fill one reaction vessel with pellets of the processed material that have been molded, and then The unit is also moved to another reaction vessel and the reaction vessel is similarly filled with pellets.

In the reaction vessel filled in this manner, a composting reaction and, if necessary, a subsequent drying reaction are carried out by sequential ventilation.

If such a method is adopted, a large-capacity treatment facility can be constructed at low cost.

If the temperature of raw manure and other materials to be processed is extremely low during winter, etc., the start of the composting reaction will be delayed, and running costs will increase due to the need to use an auxiliary heat source in conjunction with the ventilator. To prevent this, a heat exchanger is installed in the front stage,
It is effective to use warm air generated from a composting tank or a drying tank as a heat source to preheat the material to be processed.

In addition, straw, sawdust, rice husk, etc. may be used to adjust the moisture content of the material to be treated, such as input manure.

Alternatively, the input material to be treated may be dried in advance to an appropriate moisture content for the composting reaction using other methods. If obtained, underground heat, hot springs, and various waste heat energy can be used as the source, In this case, it is effective to pre-dry using the energy of sunlight using a vinyl house, plastic house, or glass house.

In order to promote the composting reaction, a chemical containing a specific aerobic bacterium as a seed bacteria may be added to the material in advance.

There are no restrictions on pellet size or shape.

As a mechanical means for forming the material to be treated into pellets prior to the composting reaction, an extrusion granulation method or a compression granulation method among so-called granulation methods is used.

Among these, the extrusion granulation method is a general term for a method of granulating the processed material by extruding the processed material under pressure toward a mold (dice) through the holes of the mold, and there are various implementation methods and limitations. There is no.

In other words, to give an example, in FIG. 5, a pellet molding machine 14' connects a hydraulic cylinder 26 to a piston 22 through a rond 27, compresses a workpiece 23 input from a hopper 20 in a chamber 21, and The opposite side of the piston is a plate 24 with a plurality of round holes.

Now, when the piston 22 is pushed toward the plate 24 with holes using hydraulic pressure, the material to be treated is compressed, and a round bar-shaped pellet 5' is released from the hole.
and fall.

In this example, the diameter of the hole was set in the range of 18 mm to 30 mm.

The length of the pellets was approximately constant (about 7 cm) because the pellets naturally broke under their own weight during extrusion.

Pellets made by extrusion granulation or compression granulation have sufficient mechanical strength, and even when stacked in a reaction vessel, the lower pellets are destroyed by the weight from the top until a considerable stacking height is reached. According to experiments, the maximum height of pellet accumulation in the reaction vessel was approximately 7 meters.

The higher the stacking height, the less floor space the apparatus occupies, which is preferable.

On the other hand, a simpler granulation method is to crush the material to be processed into pellets using blades rotating at high speed.
Pellets made by this method do not have the necessary mechanical strength, so when stacked in a reaction vessel, the weight from the top can destroy the bottom pellets even at a small stacking height of about 1 meter. This is undesirable because it obstructs the flow of air within the reaction vessel and causes an anaerobic reaction.

Furthermore, there are no restrictions on the method of introducing and removing pellets into the reaction vessel.

The simplest method is to remove a portion of the container wall after the reaction is complete, and insert a front loader of a tractor or the like to take it out.

In addition to the cold air blower, it is also possible to use a hot air blower such as an electric heating type or a combustion type to compensate for delays in composting and drying reactions at low temperatures or high humidity. If the generation of bad odors becomes a problem, a combustion type or adsorption type deodorizing device may be installed.

Similarly, to prevent the generation of dust and dirt from hammer mills, etc., a silokun or the like is sometimes installed.

Further, although a reaction vessel is used in this embodiment, the pelletized material to be treated may be piled up and the composting reaction may be carried out in an open or semi-open state without using a reaction vessel.

Furthermore, in the present invention, the material to be treated is pelletized and has extremely good ventilation, so in some cases the treatment may be carried out without special forced ventilation.

Further, in the present invention, the gas sent to deposit the pellets of the object to be treated may be oxygen or a gas containing oxygen, in addition to air.

The significance of the present invention is dogs.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a reaction container used in a conventionally known composting method, FIG. 2 a is a side sectional view of one reaction container for explaining the present invention, and FIG. Furthermore, FIG. 3a is a side sectional view showing the lower bottom of one embodiment of the reaction vessel used in the present invention, FIG. FIG. 5 is a sectional side view of an apparatus for forming a processed material into pellets. In the figure, 1 is a reaction vessel, 5' is a pellet-like processed material, 6 is a rotating shaft, and 7 is a mold wheel.

Claims (1)

[Claims] 1. When composting a material to be treated consisting mainly of organic matter such as livestock manure or sewage sludge, the material to be treated is granulated into pellets using mechanical granulation means prior to the start of the composting reaction. The granulation means belongs to the extrusion granulation method or the compression granulation method, and furthermore, the moisture content of the pellets is within the range of 20 to 70% by weight, and the deposit of the pellets of the processed material thus formed is Processing of a material to be processed, characterized in that the material to be processed is turned into compost by sending a gas containing oxygen such as air through forced or natural ventilation to cause microbial activity, mainly aerobic microorganisms. Method.