JPH10244237A - Solidifying method for material to be treated and solidified material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a solidified fuel not generating chlorine gas by mixing a dechlorination agent to solidify a material to be treated and carrying out the burning in which the solidified fuel is used. SOLUTION: A material containing plastic and a dechlorination agent are fed into a mixer 2 and mixed therein, and a mixture is heat treated at the temperature of generating chlorine gas by a heating means 4, and a formation is thermoformed by a granulator 5 to manufacture pellets. When the burning is carried out by using the pellets as a fuel, chlorine gas is reacted with a dechlorination agent to make the gas harmless and form a harmless chloride. Exhaust gas, therefore, can be exhausted as it is into atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of heating and solidifying a treated material such as waste, and a solidified material formed by this method. And a method of solidifying the mixture by mixing the same.

[0002]

2. Description of the Related Art The amount of processed waste such as municipal garbage increases year by year, and its disposal has become a problem. In general, municipal garbage is mainly discharged from general households or offices as flammable waste. Recently, it has been considered that this flammable treated material is not simply incinerated, but is effectively used as a resource, and the treated material is once solidified and reused as fuel. However, some of the processed materials contain a large amount of chlorine components in recent years, such as a wide variety of chemical substances, for example, plastics containing a large amount of vinyl chloride resin and chlorine bleach for office paper. Due to the inclusion of substances, simply solidifying will generate harmful chlorine-based gas when used and burned as fuel, and if released directly into the atmosphere, it will cause air pollution and have undesirable environmental consequences . Therefore, there is a problem in reusing as a high-efficiency and clean energy resource, and development of a technology corresponding to this problem has become an important issue.

[0003]

A problem that arises when heat-treating a treated product is the treatment of chlorine components contained in the treated product, and the chlorine-based gas (hydrogen chloride, chlorine chloride) gasified in the incineration process. Gas) is subjected to an adsorption treatment with a filter or the like so that chlorine-based gas is not discharged into the atmosphere.

[0004] On the other hand, chlorine components that have not been gasified during the heating process are combined with the treated ash, resulting in treated ash containing a high concentration of chlorine components.

[0005] If the treated ash contains a chlorine component as described above, it is difficult to reuse the treated ash as a fuel resource, and the ash is treated only by burying it in the ground.

Therefore, when reusing the treated ash,
Processed materials are separated in advance, only processed materials that generate less chlorine-based gas are selected and incinerated, and the processed ash (residue) is solidified as fuel or in a block or the like and reused.

[0007] However, since the separation of the treated material is inefficient and the resource recovery rate is low, it is desired to establish a technique for effectively removing the chlorine component.

[0008] Further, it is also practiced to solidify the processed material (garbage) and use it as a fuel. However, at present, the flammable processed material is simply compressed and solidified. Can be achieved, but when used as a fuel, harmful chlorine-based gas is generated in the same manner as described above, and countermeasures are required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to produce a chlorine-based gas (hydrogen chloride,
A solidification treatment method for a treated material that does not generate chlorine gas);
It is to provide the solidified product.

[0010]

As a result of numerous experimental investigations, the inventors of the present application have found that a chlorine component contained in a treated product and a carbonate-based alkaline substance are mixed in a proper amount as a dechlorinating agent into the treated product, and a predetermined amount is mixed. When the heat treatment is performed at a temperature of, the chlorine component is decomposed at a predetermined temperature to generate harmful chlorine-based gas, and the harmful chlorine-based gas reacts with the dechlorinating agent to generate harmless chloride, and the gas is removed. It was also found that no harmful chlorine-based gas components remained in the residue.

Attention is also paid to the fact that a dechlorinating agent is added during the heat treatment to perform a treatment aimed at the dechlorination effect. In addition, we focused on manufacturing by mixing a dechlorinating agent.

[0012] The inventors first searched for a substance having a dechlorination effect, and investigated the effect of mixing the substance into pellets and burning it.

The present invention has been made based on these experimental investigations, in which a treated product is solidified by mixing a dechlorinating agent,
When this was incinerated as a fuel, a solidified fuel that did not generate harmful chlorine-based gas could be obtained.

[0014] When the processed material is solidified by utilizing the heat softening property of the plastic contained in the processed material,
This plastic is used as a binder to form a solidified fuel having a high density and a stable shape.

In the present invention, the treatment method for solidifying the treated material comprises the steps of treating a treated plastic material containing all or a part of a plastic and a dechlorinating agent for a carbonate-based alkali substance that reacts with a chlorine-based gas. It is characterized in that it is mixed, heat-treated, and the resulting product is pressure-formed and solidified.

The temperature during the heat treatment at this time is not higher than the temperature at which the chlorine-based gas starts to precipitate (200 to 300 ° C.) or the temperature at which the melting temperature of the plastic starts (100 to 15).
0 ° C).

Then, the product is compression-molded by a granulator to form a solidified product (pellet). Alternatively, a dechlorinating agent is further added to the product to form pellets.

As the dechlorinating agent used in the present invention, a simple substance of a carbonate-based alkali substance, two or more simple substances,
Select from a mixture of two or more simple substances.

In particular, a simple substance of a carbonate-based sodium substance,
A mixture of at least one kind of simple substance and two or more kinds of simple substance is selected.

Specifically, it is selected from a simple substance selected from sodium bicarbonate, sodium carbonate, sodium sesquicarbonate and natural soda, a mixture of two or more simple substances, and a mixture of two or more simple substances.

The dechlorinating agent is used in the form of a bulk, porous, powdery (powder, granular) aqueous solution or suspension.

The amount of addition is equivalent to the treated material to be treated or 5 equivalents.
To 30% by weight, or 0.5 to the generated chlorine-based gas
Add ~ 1.5 mol.

The pressing force for producing a solid is 10 to 1000 kg / kg for reasons such as solidification is difficult if the pressing force is small, and the equipment becomes large if the pressing force is large.
cm ² is preferred.

Under the above conditions, a dechlorinating agent is added to the treated product and heat-treated, and the produced product is solidified and used as a fuel. For example, when sodium hydrogen carbonate (NaHCO ₃ ) is added, Reacts with the generated hydrogen chloride (HCl) to give:

(NaHCO ₃ ) + (HCl) → (NaC
l) + (H ₂ O) + (CO ₂ ) From this, if there are Na and CO components, the chlorine component becomes
It becomes NaCl, water (H ₂ O), and gaseous CO ₂ , which are a part of the residue, and does not generate a chlorine-based gas that contributes to dioxin, thereby making the gas and the residue harmless.

In addition, harmless chloride NaC in the residue
l (sodium chloride) can be easily washed and removed with a solution such as water, and naturally, no harmful chlorine-based gas component exists in the carbide after the removal of chloride.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a conceptual diagram of an embodiment of the present invention.
Denotes a processing material supply unit, 2 denotes a mixer, and 3 denotes a dechlorinating agent supply unit. Reference numeral 4 denotes a heating means for heating the processed material in the mixer 2.
The heating means 4 includes gas heating, electric heating or combustion heating,
Any heating means such as microwave heating and induction heating may be used.

Numeral 5 denotes a granulator having a heating means 6 on the outside and a press means comprising a pressure roller and the like inside.
Reference numeral 7 denotes a solidified product (pellet) formed by the granulator 5.

The procedure for manufacturing the pellets is as follows. First, the processed material is charged into the processed material supply unit 1, the dechlorinating agent is stored in the dechlorinating agent supply unit 3, and these are supplied to the mixer 2 at a predetermined ratio. I do. In the mixing machine 2, while mixing the processed material and the dechlorinating agent,
200 ° C. or less, preferably 100 ° C.
A heat treatment (dry distillation) is performed for 10 minutes at a temperature of 150 ° C. with the outside air shut off.

Next, the opening / closing door 2b of the mixer 2 is opened, the mixture is supplied to the granulator 5, and the mixture is compression-molded by press means while heating the mixture under the same temperature conditions as described above. Then, a pellet 7 is formed. The crushing function may be added to the mixer 2.

In the above process, if plastics are mixed in the processed material, the plastics are supplied in a softened state (if they are not mixed or the amount is small, they are separately supplied from the processed material supply unit 1). As it is mixed with the material and molded, it serves as an adhesive (binder) between the processed materials, and the produced pellets maintain a stable solid shape.

The pressing means includes, for example, a feed rotary roller for feeding out the mixture and a squeezing rotary roller (which may be a heating roller) for compression molding. / C
to adjust to the m ^2. If the pressure is small, solidification is difficult, and if it is too large, the equipment becomes large.

By performing compression molding in this manner, the volume ratio of the pellets is reduced as follows.

[0035]

[Table 1]

FIG. 2 shows another embodiment of the present invention, in which a screw feeder 10 is provided between the mixer 2 and the granulator 5. The screw feeder 10 includes a heating unit 11
And provided to further promote the mixing of the treated product and the dechlorinating agent.

Since the screw feeder 10 is also heated in a dry distillation state, it is configured to be shielded from outside air. Accordingly, the inlet side and each have a door 10d ₁ and 10d ₂ on the outlet side, rotary driven screw 10b is provided in the cylindrical member 10a, transported while mixing the treated product and the dechlorinated agent.

The heating may be performed in either the mixer 2 or the screw feeder 10, or may be performed in both.

Several processed materials (pellets) solidified by the above-described processing method are placed in a closed vessel equipped with an exhaust pipe, heated in an electric furnace, the generated gas is extracted, and the hydrogen chloride concentration (p
pm), no hydrogen chloride was detected.

Further, as a result of taking out the treated ash and detecting a chlorine component, only harmless chloride (sodium chloride) was detected.

From this, it was found that the harmful chlorine-based gas that would be generated forms harmless chlorides, and that the exhaust gas and the residue do not contain harmful chlorine-based gas components.

That is, the following experimental investigation revealed that the carbonic acid-based alkali substance reacts with the harmful chlorine-based gas in the gas to generate harmless chloride.

In the experiment, first, a sample shown in Table 2 was prepared using polyvinylidene chloride containing a large amount of a chlorine component.
When 4 g of polyvinylidene chloride was added with 20 g of sodium bicarbonate powder as a dechlorinating agent (Example 1),
When no dechlorinating agent was added (Comparative Example 1), when 20 g of slaked lime powder was used as the dechlorinating agent (Comparative Example 2), and when 20 g of calcium carbonate was used as the dechlorinating agent (Comparative Example 3) A comparative experiment was performed.

[0044]

[Table 2]

As a result of the experiment, as shown in Table 4, good results were obtained when sodium hydrogen carbonate was added.

Therefore, a simulated garbage simulating the following standard municipal garbage was prepared, and polyvinylidene chloride was added to create a more severe situation, and the amount was changed, and the amount of the dechlorinating agent was changed. Experiments (additional tests) for practical use of Example 2, Example 3, Example 4, and Example 5 were conducted. In addition, the influence of moisture was also examined.

As the dechlorinating agent, a powder having an average particle size of 100 μm was used.

20% by weight of simulated garbage 50% by weight of plastic (PE, PP, PS, PVDC) 20% by weight of paper (tissue, newspaper, wrapping paper, box, beverage pack) 10% by weight of cloth (such as waste cloth)・ Crushed garbage

[0049]

[Table 3]

In the experiment, the sample was placed in a closed vessel with an exhaust pipe, heated in an electric furnace, and heated from 250 ° C. to 600 ° C.
The temperature was maintained at each temperature for 5 minutes at intervals of ° C, and the concentration (ppm) of hydrogen chloride gas (HCl) was measured at the time of temperature rise and at the time of keeping.

The gas concentration was measured using a detector tube specified in JIS-K0804.

Table 4 shows the measurement results. The hydrogen chloride gas concentration is a value measured in 10 experiments and is shown in Examples 1 to 5.
Indicates the highest value, and Comparative Examples 1 to 3 indicate the lowest values.

Note that "ND" represents "not detected" and 1
It shows that none was detected in 0 experiments.

[0054]

[Table 4]

In the experiment, first, a preliminary experiment was performed using only polyvinylidene chloride containing a large amount of a chlorine component.
The results are shown in Comparative Example 1 of Table 4.

Next, an experiment was conducted by adding a conventionally known powder of slaked lime and calcium carbonate as a dechlorinating agent.
The results are shown in Comparative Examples 2 and 3.

Next, an experiment was conducted by selecting the sodium hydrogencarbonate of the present invention. The results are shown in Example 1.

Subsequently, an experiment was conducted using simulated garbage simulating the above-mentioned standard municipal garbage and changing the amounts of polyvinylidene chloride and sodium hydrogen carbonate. The results are shown in Examples 2, 3, and 4.

Further, water was added to the simulated garbage to examine the effect of the water. The results are shown in Example 5.

From the results shown in Table 4, the following is considered. First, when polyvinylidene chloride containing a large amount of chlorine component was treated, Comparative Example 1 in which no dechlorinating agent was added
In this case, a large amount of hydrogen chloride gas is generated over each temperature for the heat treatment. In Comparative Example 2 in which slaked lime as a conventional dechlorinating agent was added to this treated product, and in Comparative Example 3 in which calcium carbonate was added as a dechlorinating agent, generation of hydrogen chloride gas was considerably suppressed as compared with Comparative Example 1. But not yet enough.

On the other hand, in Example 1 in which sodium hydrogen carbonate was added as a dechlorinating agent to the above treated product, hydrogen chloride gas was not detected over the entire temperature range, and extremely good results were obtained. Furthermore, in the cases of Examples 2, 3, and 4 in which the amount of sodium hydrogencarbonate added as a dechlorinating agent was changed for the treated product obtained by adding polyvinylidene chloride to simulated garbage, over the entire temperature range, Hydrogen chloride gas was not detected.

Further, in the case of Example 5 in which sodium bicarbonate was added to a processed product obtained by adding moisture to simulated garbage, the temperature was raised and kept at 450 ° C., and the temperature was raised at 500 ° C. Although a slight generation of hydrogen chloride gas was observed, generally, even if water was present, it was hardly affected, and a very good result was obtained as compared with Comparative Example 2 using slaked lime as a dechlorinating agent. Obtained.

According to the above experimental investigation, when a substance containing a chlorine component is dechlorinated by thermal treatment, a carbonate-based alkali substance (particularly, a sodium-based substance) reacting with a harmful chlorine-based gas is dechlorinated. It was confirmed that harmless treatment can be achieved by adding and treating.

The same effect was obtained at a temperature of 600 ° C. or higher to 1000 ° C.

In Table 4, when sodium hydrogen carbonate reacts with chlorine-based gas, detoxification of gas and residue can be realized as follows because harmful chlorine-based gas reacts harmlessly by solid-phase / gas phase reaction. It is due to being formed by substitution with chloride.

(1) In the case of sodium hydrogen carbonate When sodium hydrogen carbonate (NaHCO ₃ ) is added, it reacts with aqueous chloride (HCl) to give the following.

(NaHCO ₃ ) + (HCl) → (NaC
l) + (H ₂ 0) + (CO ₂ ) When water is present (NaHCO ₃ ) + (H ₂ O) → (NaOH) + (H ₂ C)
O ₃ ) (NaOH) + (H ₂ CO ₃ ) + (HCl) → (NaC
1) + (H ₂ O) + (CO ₂ ).

(2) In the case of sodium carbonate When sodium carbonate (Na ₂ CO ₃ ) is added, it reacts with hydrogen chloride (HCl) to give the following.

(Na ₂ CO ₃ ) + (2HCl) → (2Na
Cl) + (H ₂ O) + (CO ₂ ) (3) In the case of sodium sesquicarbonate The chemical reaction is represented by the chemical formula Na ₂ CO ₃ .NaHCO ₃ .2H ₂ O, and a reaction similar to the above (1) and (2) is performed. Then, harmful hydrogen chloride (HCl) is replaced with harmless chloride (NaCl) to generate.

Accordingly, the chlorine-based gas becomes NaCl, which is a part of the residue, water (H ₂ O) and gaseous CO ₂ , and harmful chlorine-based gas which is a cause of dioxin is not generated. Harmless exhaust gas and residue can be realized.

On the other hand, NaCl generated by the reaction is a harmless chloride, and this NaCl can be effectively removed by washing with a solution such as water.

FIG. 3 is an explanatory view of washing the treated ash. The treated ash is put into a water tank, and stirred for a predetermined time (about 30 minutes) to dissolve sodium chloride (NaCl) in water and to remove it from the treated ash. Next, this is dehydrated and dried to be solidified. After cleaning, valuable carbonized material remains.

Further, since the treatment liquid after washing contains almost no harmful substances, it can be discharged by a simple treatment.

From the above, it is clear that similar results can be obtained if there is a component that reacts with the chlorine component (Cl) to form harmless and stable chlorides. The following substances can be used:

(1) A substance selected from a simple substance of a carbonate-based alkali substance, two or more simple substances, and a mixture of two or more simple substances.

(2) Carbonic acid-based sodium substance (3) Single substance selected from sodium bicarbonate, sodium carbonate, sodium sesquicarbonate, natural soda, a mixture selected from two or more simple substances, and a mixture of two or more simple substances .

Note that sodium hydrogen carbonate (NaHC)
O ₃ ) is also referred to as (a) sodium acid carbonate (b) sodium bicarbonate (c) sodium bicarbonate, and is also commonly referred to as baking soda.

Sodium carbonate (Na ₂ CO ₃ ) is also called sodium carbonate or simply soda as another name, and anhydrous salt is also called soda ash, and decahydrate is also called washing soda or crystal soda. .

Sodium sesquicarbonate (Na ₂ CO ₃ .Na
HCO ₃ .2H ₂ O) is also referred to as (a) sodium monocarbonate bicarbonate (b) sodium bicarbonate (c) sodium sesquicarbonate, and is naturally produced as trona (natural soda).

On the other hand, NaCl is produced by the reaction, and the produced NaCl is a harmless chloride as described above. This NaCl can be effectively removed by a washing treatment with a solution such as water. Reusable carbonized material remains.

The concentration of hydrogen chloride in the residue not washed with water was measured.
As described above, it was not detected in the present invention.

[0082]

As described above, according to the present invention, a treatment containing plastics is mixed with a dechlorinating agent, and firstly heat-treated at a temperature lower than a temperature at which chlorine-based gas is deposited, and then pressurized. Because solidified material (pellet) is formed, (1) when burning the solidified material, there is no generation of chlorine-based gas, and the plastics soften to serve as a binder for the mixture, Pellets of stable shape, easy to handle
That is, pellets suitable for carrying or transporting are obtained.

(2) Even when the pellets are burned as fuel, the presence of the dechlorinating agent reacts with the chlorine-based gas in the generated gas to form harmless chlorides. Since gas components can be effectively removed, generation of dioxins is prevented even if the gas components are released into the atmosphere as they are.

(3) Since plastics have a high burning power, when burning pellets, the burning power (thermal power) of the processed material is increased.

(4) Pellet can be obtained if there is no generation of chlorine-based gas (hydrogen chloride, chlorine gas) when the solidified material is burned.

(5) For the above reasons, it can be effectively reused as a solidified fuel which is convenient to handle.

The following effects are obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an embodiment of the present invention.

FIG. 2 is a conceptual diagram of another embodiment of the present invention.

FIG. 3 is an explanatory diagram of the processing of the processing ash.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Process supply part 2 ... Mixer 3 ... Dechlorinating agent supply part 4, 6 ... Heating means 5 ... Granulator 7 ... Pellets

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B09B 3/00 304H

Claims (12)

[Claims] 1. A mixture containing a plastic and a dechlorinating agent for a carbonate-based alkali substance that reacts with a chlorine-based gas, and heat-treated. A solidification treatment of a processed product, wherein the solidification is performed by using a binder as a binder. 2. The method according to claim 1, wherein the heat treatment temperature is equal to or lower than a temperature at which precipitation of chlorine-based gas starts. 3. The method according to claim 1, wherein the heat treatment is performed in a low oxygen atmosphere. 4. The method according to claim 1, wherein the heat treatment is dry distillation. 5. The heat treatment temperature is a temperature at which the plastics are softened at a temperature not higher than a temperature at which the plastics are melted,
5. The method according to claim 1, wherein the plastics contained in the processed material act as a binder. 6. The solidification treatment of a treated product according to claim 1, wherein the dechlorinating agent is selected from a simple substance of a carbonate-based alkali substance, two or more simple substances, and a mixture of two or more simple substances. Method. 7. The method according to claim 1, wherein the dechlorinating agent is a carbonate-based sodium substance. 8. The dechlorinating agent is selected from a simple substance selected from sodium hydrogen chloride, sodium carbonate, sodium sesquicarbonate and natural soda, a mixture of two or more simple substances, and a mixture of two or more simple substances. A method for solidifying a treated product according to claim 1. 9. The dechlorinating agent may be in the form of a block, a plate, a porous,
The method for solidifying a treated product according to any one of claims 1, 6, 7, and 8, wherein the method is formed in any of a powder, a solution, and a suspension. 10. The method according to claim 1, wherein the amount of the dechlorinating agent is 5 to 30% by weight of the processed material.
10. The method for solidifying a treated product according to any one of 6 to 9. 11. The pressure for molding under pressure is 100 to 1000.
^{2. The} method for solidifying a treated product according to claim 1, wherein the solid content is set to kg / cm ² . 12. A processed material containing plastics,
A solidified material characterized by mixing a chlorine-based gas with a dechlorinating agent of a carbonic acid-based substance that reacts with a chlorine-based gas, heat-treating the resultant, and press-forming the resulting product to solidify using a plastic as a binder.