KR20070098236A - The poisonous gas decrease type solid fuel manufacture method - Google Patents

Abstract

A method for manufacturing solid fuel is provided to make it possible to recycle aluminum metal material included in ADP(Aluminum Dross Powder), which is a by-product of aluminum industry. ADP having aluminum of more than 7% is mixed into an amylaceous binder. The mixed product is molded into harmful gas-reduction type solid fuel, wherein the harmful-reduction type solid fuel is selected from a briquet(1A), a pellet(1B), and an oval briquet(1C). The harmful gas-reduction type solid fuel is manufactured by mixing 70-95 wt% of briquet powder into 5-30 wt% of ADP having aluminum of more than 7%.

Description

The poisonous gas decrease type solid fuel manufacture method

Figure 1 is an illustration of briquettes, pellets (ii), shellfish (만) made only with ADP group of more than 7% Al content

Figure 2 is an illustration of briquettes, pellets (ii) and clam shells prepared by mixing 5% by weight to 30% by weight of ADP and 95% by weight to 70% by weight of briquette powder.

FIG. 3 is a briquette made by mixing 5-30 wt% of pellets made of termit and 95-70 wt% of briquette powder prepared by mixing 5-30 wt% of iron oxide powder with 75-95 wt% of ADP in an amount of 7% or more. Iii), pellets (ii), shell coals.

Figure 4 is a cross-sectional view of the tissue particles of Figure 2

Figure 5 is a cross-sectional view of the tissue particles of Figure 3

※ Explanation of symbols for main parts of drawing

1: Coal powder 2: ADP (Al dross Powder)

3: iron oxide 4: thermal pellet

1A; 2A; 3A: briquette 1B; 2B; 3B: pellet

1C; 2C; 3C: shell shell

The present invention relates to a method for producing a toxic gas-reduced solid fuel, in particular using thermite reaction that uses heat generated by burning metal aluminum contained in aluminum dross powder, a by-product of the aluminum industry, as energy. It is a new fuel field.

Combustion of aluminum dross containing 7% or more of metal aluminum has an exothermic effect, and the basic component of the residue after combustion is aluminum oxide (Al ₂ O ₃ ), which can be used as alumina-based refractory material and alumina cement.

In addition, when the aluminum bristle powder (hereinafter referred to as 'ADP') used in the present invention is mixed with the general briquettes currently used, and used as fuel, carbon dioxide gas and harmful toxic gas that are harmful to human body are used. It is to reduce the generation of carbon monoxide.

World energy consumption is proportional to economic growth and population growth. Consumption, which amounted to 3.9 billion tons in 1965, was 9.3 billion tons in 2003.

The demand for petroleum-based raw materials is rapidly increasing, and the price of crude oil as a raw material is fixed at twice the previous level.

Relying only on oil, which is limited, creates an energy crisis on a global scale, predicting social and economic turmoil and international conflict.

At the beginning of the 21st century, nature is alarming people, and it's important to note that people are paying attention to energy issues and have come to the stage of reassessing the fuel of oil today.

The present invention pays attention to coal, which is rich in reserves and widely distributed according to the demands of the times, and adds an energy source to the coal, thereby increasing energy efficiency and reducing the generation of carbon monoxide and toxic gas, carbon monoxide. To provide solid fuel.

In other words, briquettes incorporating ADP into coal-based briquettes are not used to reclaim the residue after combustion, but are used as building materials to help maintain the global environment.

Next, ADP powder alone and iron oxide powder are blended if necessary without using coal powder to provide a new combustible fuel by thermite reaction.

By thermite reaction, the residue after combustion has more than 80% of the basic component of alumina, which can be reused as a raw material of refractory material and alumina cement.

Conventional briquettes have been widely used as fuel using coal powder. However, petroleum fuel tends to be easy to handle and good in energy efficiency.

However, the recent surge in oil prices has brought the coal industry back to life.

The base material used in the present invention is aluminum slag which is by-product of coal powder and aluminum melting process.

The slag generated in the aluminum melting process is called as primary aluminum dross in the industry, and its basic components are aluminum oxide and remaining metal aluminum.

The slag aluminum content is generally recognized as 30-50%, which is mainly recovered by dross specialists.

In the dross processing step, residues remain in addition to the recovered metal. The residues are called secondary dross.

This secondary dross contains 10-30% of metallic aluminum. Metal aluminum is also recovered in the secondary dross. The next residue is called the tertiary dross, which is usually about 10% aluminum.

Aluminum is recovered in the process of the first ⇒ second ⇒ third, and the dross processing treatment in which powder and solids are mixed is basically as follows.

Dross → grinding → particle size selection → 1mm particle size is used for aluminum recovery, 1mm ~ 100mesh particle size is used as deoxidizer for steelmaking, and the particle size of about 100mesh is less used.

In the present invention, it is intended to use aluminum dross powder (AL dross Powder) under 100mesh coming out from the process.

In the present invention, metal aluminum utilizes energy generated during oxidative combustion. Metal aluminum undergoes the following oxidation reaction.

(Scheme)

2Al + 3O → Al ₂ O ₃ +400 Kcal / mol... … … … … … … ①

2Al + Fe ₂ O ₃ → 2Fe + Al ₂ O ₃ +204.7 Kcal / mol. … … ②

2Al + 3FeO → 3Fe + Al ₂ O ₃ +210.4 Kcal / mol... … … ③

7,407 Kcal / Al kg

3,791 Kcal / Al kg in terms of Al in 1kg

Scheme 3 is not considered inclusive in 2.

Meanwhile, briquettes

C + O ₂ → CO ₂ +97.0 Kcal / mol -------- 8,083 to kcal / kg-C... … … ④

C + 1 / 2O ₂ → CO + 29.39 Kcal / mol -------- 2,449 kcal / kg-C... … … … ⑤

The present invention is to use the heat of reaction generated by mixing the metal aluminum in the ADP and iron oxide which is oxygen or solid oxygen supply in the air.

Briquettes use combustion heat generated by burning carbon by using oxygen in the air. However, insufficient supply of air (oxygen) may cause carbon monoxide, a toxic gas, which may cause personal injury.

Thermit reaction (Thermit reaction) is because no toxic gas is generated in the present invention is to use the combustion energy and thermite reaction energy of briquettes at the same time.

In view of the above-mentioned point and look at the detailed configuration and operation of the present invention.

The constituent material of the present invention is an anthracite coal, coal, charcoal, coke and ordinary briquette manufacturing raw material (hereinafter referred to as 'briquette powder') produced by calcination, as a raw material.

Adding slaked lime removes sulfur dioxide generated when the sulfur component is burned.

In other words, thermite reaction energy is to be used simultaneously for the coal combustion energy. Before discussing practical formulation, the reaction of the ADP + iron oxide material, which is thermite, will be examined.

Commonly, the termites occur between pure metal aluminum and high-purity iron oxide. Commonly, alumina, such as ADP, contains about 10% of metal aluminum, and other components are metal oxides such as alumina that interfere with the reaction.

In order to confirm this reaction, the present invention carried out a basic experiment confirming the following contents in advance.

Based on the above-described reaction formula ②, a review was performed, which means that 2 mol of 54 g of Al and 160 mol of 1 mol of iron oxide react to produce 112 mol of 2 mol of iron and 102 mol of alumina.

When the purity of the materials used is high, the reactions occur without any problem and give a temperature of about 3000 ° C.

Here, instead of the metal Al, which is made of thermite, thermite was prepared by mixing 10% ADP with Al and iron oxide (about 90% purity) produced in steel mills. .

Example 1

Combination, combustion, and shaping of ADP and iron oxide

In the standard mixing scheme ②, the combination of metal Al and iron oxide is

2Al: Fe ₂ O ₃ = 54: 160 That is, the metal Al: iron oxide = 1: 3 weight compounding becomes a theoretical value.

In fact, the mixture of the two materials in this formulation complexes with a magnesium ribbon and the thermite reaction occurs.

Care is needed because the reaction is instantaneous and explosive.

Does the material used in the present invention actually cause thermite reaction? In order to confirm the following experiment was carried out.

Characteristics of the prepared ADP; 10.2% ≒ 10% metal Al below 100mesh particle size and 89.6% ≒ 90% iron oxide below 100mesh particle size were prepared in a graphite crucible. Observed.

NO ADP Iron oxide Ignition Combustion shaping 1-1 1000 g 0g ○ Complex 1-2 950 g 50 g ○ Chain reaction 1-3 900 g 100 g ○ Chain reaction 1-4 800 g 200 g ○ Chain reaction 1-5 700 g 300 g △ No continuous combustion 1-6 500 g 500 g × No combustion 1-7 400 g 600 g × No combustion 1-8 300 g 700 g × No combustion 1-9 200 g 800 g × No combustion

When using ADP material in this experiment, contrary to the theoretical value, it is found that the compounding of iron oxide is 0 to 30%, and importantly, even ADP alone is combusted without iron oxide.

When ADP is used alone, moldings such as pellets (1B) and briquettes (1C) of 5 to 10 mm are preferable, as shown in Figs.

Even combustion of ADP alone means that ADP reacts with oxygen in the air even without iron oxide, a solid oxygen feed material.

Therefore, this invention means that the mixture of briquette powder and ADP may be sufficient. Iron oxide can be considered as an additive to control the combustion rate.

Example 2

Minimum Al content of ADP for fuel.

On the other hand, what was the minimum Al content in the ADP required for the thermite reaction?

In the same graphite crucible as in Example 1, the amount of iron oxide was fixed to prepare a powder thermite compound of the following formulation, and the complexing and combustion form were observed.

NO Al content in ADP Iron oxide Ignition, Combustion 2-0 0% ADP 700g 300 g Do not ignite 2-1 700 g of ADP including 2% 300 g Do not ignite 2-2 700% ADP 700g 300 g Ignition, but weak 2-3 8% ADP 700g 300 g Ignites 2-4 700% of ADP including 7% 300 g Ignites

Through Example 2, when using a material having a low metal Al content as the thermite, such as ADP, the actual reaction does not occur at the theoretical iron oxide: alunium = 3: 1 ratio, and the Al content in the ADP is at least 7 An important reference characteristic that% should be included was identified.

That is, in the practical use of the present invention, it can be specified that the metal Al content in the ADP is exothermic only when 7% or more.

If ADP is set to 100, the metal Al that generates heat by oxidative combustion is 7, and the rest of Al ₂ O ₃ is assumed, Al ₂ O ₃ This means that heat is absorbed and does not generate heat.

This is similar to the enthalpy calculated that when the ADP is injected into the oxygen converter of the steelmaking process, the Al content in the injected ADP is only 6.6% to generate heat.

The enthalpy calculation is developed here.

Specific heat of Al ₂ O ₃

CP = 27.49 + 2.82 × 10 ² T-8.35 × 10 ⁵ × 1 / T (Cal / mol ° K)

Al ₂ O ₃ The enthalpy change of 27 ℃ → 1650 ℃ per mol

a = 300 ° k, b = 1923 ° k

△ H2 = 464 (KCal / Kg) for 1 kg

2Al + 3 / 2O _{2 on the other} → Al ₂ O ₃ The enthalpy change in the reaction

ΔH 3 = 400,000 (Cal / mol Al ₂ O ₃ )

The calorific value of Al 1kg is ΔH4 = 7407 (Kcal / kg Al)

If Al and Al ₂ O ₃ are fixed at a constant ratio in ADP composition, the calorific value of Al oxidized combustion and Al ₂ O ₃ originally existed in ADP. And the endothermic amount due to Al ₂ O ₃ generated by oxidizing Al.

If you get a composition that balances this fever and absorption

Endothermic △ H2 = 464 (Kcal / kg) by Al ₂ O ₃

Heat generated by Al △ H4 = 7407 (Kcal / kg Al)

On the other hand, Al 1Kg is oxidized to 1.89kg of Al ₂ O ₃ , so the thermal balance of ADP 1Kg containing X% of Al is

Fever due to Al xkg × 7407 Kcal / kg = 7407 × Kcal... … … … (One)

Endothermic [(1-x) + 1.89x] kg × 464 Kcal / kg = (0.89x + 1) × 464 Kcal by Al ₂ O ₃ . … (2)

Equivalent to (1) and (2) can be obtained x = 0.066.

That is, when the Al content is 6.6%, the heat balance is 0, and when it is 6.6% or more, it means that heat is generated.

Based on the above characteristics of the ADP, it is first necessary to find out whether the ADP itself burns. In order to confirm this, Example 3 was carried out as follows.

Example 3

Combustion test of ADP group.

5% by weight of starch binder was added to the ADP powder having 10% Al content, and water was added to make pellets having an average of 10 mm and dried.

This material was set to 3-1.

In the test, the degree of heating was first heated, and then 500 g of test material was put therein and ignited with magnesium ribbon.

It was found that the test pellets ignited and burned on their own.

In other words, it was found that ADP is combusted in an air atmosphere, and since there is no carbon component in ADP, carbon dioxide and carbon monoxide are not generated.

Next, it is necessary to examine the possibility that fuel composed of ADP and briquette powder (including 3% slaked lime) becomes a fuel.

In order to know this possibility, Example 4 was carried out as follows. Test materials were carried out with granules made in the same manner as in Example 3.

Example 4

A mixture of ADP and briquettes.

NO Briquette powder (% by weight) ADP (% by weight) Situation Observation 4-1 95 5 Combustion without abnormality 4-2 90 10 Combustion without abnormality 4-3 80 20 Combustion without abnormality 4-4 70 30 Burn out 4-5 60 40 Difficulty 4-6 70 30 Difficulty

In Example 4, it was confirmed that the ADP was added to the briquette powder in a fuel effect even when blended up to 30% by weight.

Through experiments 1 and 2, it was found that the blending ratio of iron oxide to ADP should be 0-30 wt%, and the Al content in ADP should be 7 wt% or more.

When carbon materials such as coal, which is the basic material of briquettes, are mixed with thermite agent composed of this property, a rational mixing of the carbon material and the thermite material is required.

Example 5 was carried out to determine this rational formulation.

Example 5

Blending and Ignition Test of Carbon and Thermite Materials

The characteristics of the material used for the test are as follows.

ADP: Metal Al content 10%, powder particle size below 80mesh

Iron oxide: FeO ₃ purity above 85%, particle size below 1mm.

Carbon material: Briquette powder (contains 3% of lime)

Thermite material: ADP: Iron oxide is fixed at 80: 20 wt%

Combination of briquette powder and thermite Formulation Number Briquette powder Thermite Pellets Combustion situation A-1 100% 0 Standard combustion A-2 80% 20 Burning speed is faster than A-1 A-3 60% 40 Burning speed is faster than A-2 AB 50% 50 Not suitable for fuel due to rapid combustion B-1 40% 60 Not suitable for fuel due to rapid combustion B-2 20% 80 Not suitable for fuel due to rapid combustion B-3 0 100 Fast burning speed, not suitable for fuel

In the experiment, first, the termit agent was used to make a small pellet about 5mm in diameter by using the method of Experiment 3, and the pellet was used as a nucleus to attach briquette powder to the surface to make a larger pellet (about 30mm).

Therefore, it can be understood that the prototypes of A-1 to B-3 contain a small pellet made of thermite in a large pellet. 500 g of this was put into the furnace, and the combustion test was carried out.

As a result of the experiment, A-2 ~ A-3 showed interesting trend. AB and B1 ~ B3 have a short temperature holding time and are not suitable for falling behind briquettes.

In order to further realize the invention, the A-based fine blend test was conducted.

Example 6

Briquette powder and thermite fine blend

Formulation Number Briquette powder Thermite material 2A-1 90 10 2A-2 85 15 2A-3 80 20 2A-4 75 25 2A-5 70 30

Example 6 showed that 2A-3 and 2A-4 have a similar effect to the conventional briquettes.

It is clear that the amount of carbon dioxide and carbon monoxide generated decreases in proportion to the amount of thermite.

Through the basic experiments, it is clear that the granules composed of briquette powder and ADP or thermite have less carbon dioxide and carbon monoxide than conventional briquettes.

The present invention is a solid fuel produced by the method for producing a toxic gas-reducing solid fuel and a composition thereof, which is used as a solid fuel such as briquettes, pellets, or briquettes. It also has the advantage of recycling the metal aluminum contained in the dross powder, and the solid fuel mixed with the aluminum dross powder alone or the iron oxide by mixing with the existing briquette raw material is carbon dioxide and ADP compounded amount. There is an environmentally friendly effect that can reduce the emissions of carbon monoxide and the residue after combustion is a useful invention that is collected and reused as alumina-based raw materials, alumina-based refractory.

Claims (3)

A method for producing a toxic gas-reducing solid fuel selected from briquettes, pellets, and briquettes by mixing and molding ADP alone having an AL content of 7% or more with a starch binder. According to claim 1, Al content of at least 7% ADP powder 5 to 30% by weight of briquette powder 95 to 70% by weight of any one selected from briquettes, pellets, briquettes reduced toxic gas Type solid fuel manufacturing method. According to claim 1, 5 to 30% by weight of thermite agent and briquette powder 95 obtained by mixing 5 to 30% by weight of iron oxide powder with 70 to 95% by weight of ADP powder having an AL content of 7% or more. A method for producing toxic gas-reduced solid fuel selected from briquettes, pellets, and briquettes by mixing ~ 70% by weight.

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