KR101977353B1 - Method for Manufacturing Solid Fuel Containing Coffee Waste - Google Patents

Abstract

The present invention relates to a method for producing a solid fuel having excellent calorific value by mixing a coffee bean, which is a by-product of coffee, with a pine cone powder and compression-molding them while firmly maintaining the molded form.
The coffee ground solid fuel produced by the method of the present invention has a high calorific value and is firmly maintained in a molded form so that it does not break easily during handling and emits a gentle coffee aroma when burned, Talc powder, calcium hydroxide powder, and quicklime powder can reduce the generation of smoke and carbon dioxide, so consumers' preference is high and they are not restricted in use.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for manufacturing a solid fuel,

The present invention relates to a method for producing a solid fuel having excellent calorific value by mixing a coffee bean, which is a by-product of coffee, with a pine cone powder and compression-molding them while firmly maintaining the molded form.

Recently, as greenhouse gas reduction due to global warming has become a global hot topic, interest in renewable energy that can replace fossil fuels is increasing. As a result, biomass such as wood chips and wood pellets, ) Research and development on processed fuels is actively being carried out.

Fuel pellets based on wood or wood byproducts have many merits such as high combustion efficiency, excellent ignitability, and preservability. However, since the supply is not satisfying the increase in demand, the price is continuously rising and the high moisture content , Which has a problem in that the heat loss is large and adverse effect on the global environment due to the fuel supply in terms of fuel supply.

Accordingly, development of biomass-processed fuels capable of replacing wood pellets has been demanded. As such alternative fuels, attempts have been made in recent years to use the discarded coffee by-products as raw materials for new fuels.

Coffee is the favorite food of all over the world, and the amount of consumption is continuously increasing. As a by-product of extracting coffee liquor, coffee bean has excellent air permeability, uniform particle size and 15 ~ 25% of coffee oil Solids are energy resources with high calorific value, and have a higher heating value of about 6500 ㎉ / ㎏, better than wood of about 4000 ㎉ / ㎏, and about 2% by weight of ash, , Pellets, etc., contain a small amount of lignin, which acts as an adhesive in molding, and can be processed. Thus, they are attracting attention as new energy resources that can replace conventional wood pellets.

However, the conventional fuel pellets using the coffee by-products are relatively poor in durability, and in particular, the lower heating value does not reach the level required for the fuel pellets, and the formability is not sufficient due to insufficient formability, It is used as a raw material for some organic fertilizer, and most of it is incinerated or buried like general garbage.

Accordingly, various methods for applying as a biomass fuel using coffee by-products have been proposed. For example, Korean Patent Publication Nos. 033212, 1343472, 1579115, 1705612 and Korean Patent Laid- 2015-0065270 proposes an invention in which a solid fuel is produced by mixing sawdust, rice husks, charcoal or the like with coffee by-products (coffee beans, coffee husks) and pressure-molding them.

The above-mentioned problems have been solved by adding sawdust, rice hull and the like to the problems of forming defects during molding into a molded article due to insufficient adhesion strength, which is a disadvantage of coffee by-products, and problems of not being easily ignited due to high ignition point. The amount of sawdust, rice husks, etc. added to the coffee by-products must be increased. As the content of the additive increases, the amount of heat generated by the solid fuel decreases, thereby failing to satisfy the required calorific value.

Disclosure of Invention Technical Problem [7] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a method for producing a solid fuel.

In order to solve the above-mentioned problems, the present invention provides a method for producing a pine cone by pulverizing a pine cone, Mixing 60 to 80% by weight of a coffee bean with 20 to 40% by weight of the pine cone powder and drying at a temperature of 100 to 120 ° C for 1 to 4 hours to a moisture content of 2 to 5% by weight; Adding 3 to 7 parts by weight of talc powder and 1 to 5 parts by weight of calcium oxide powder to 100 parts by weight of the dried mixed powder; And pressurizing and molding the mixed powder to which the talc powder and the calcium oxide powder are added at a pressure of 1800 to 2200 kgf / cm 2.

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The coffee ground solid fuel produced by the method of the present invention has a high calorific value and is firmly maintained in a molded form, so that it is not easily broken during handling and emits a soft coffee aroma when burned, thereby enhancing the merchantability.

In addition, the talc powder, the calcium hydroxide powder and the quicklime powder which are added to the coffee bean and the pine cone powder can reduce the generation of smoke and carbon dioxide, so that consumers' preference is high and they are not restricted in use.

Figs. 1 to 3 are test reports analyzed by Daedeok < (R) > Institute of Technology, Inc. for the solid fuel produced in Example 1. Fig. 1 shows the water content and ash content of coffee ground- Shows the moisture content and ash content of the coffee bean-pine needle powder / pine cone powder, and FIG. 3 is a test report showing the calorific value of the coffee bean-sawdust / pine needle powder / pine cone powder.
Fig. 4 is a photograph showing a state of a solid fuel produced by mixing a coffee bean and a sawdust at different mixing ratios.

The present invention relates to a method for producing a solid fuel by mixing a coffee bean, which is a by-product of coffee, with a pine cone powder, drying and compression-molding at a high pressure.

In general, solid biofuels using biomass have a high calorific value and a low water content and ash content. The higher the durability, the better the quality. The water content can be lowered through the drying process, but the calorific value, ash content, And it is also possible to make some adjustments according to the manufacturing method.

Generally, a solid fuel using a coffee by-product is prepared by mixing a sawdust and a rice husk into a coffee bean. Since the coffee bean has a large calorific value but poor moldability and poor durability, sawdust containing lignin serving as an adhesive for improving durability Add rice hulls and others.

However, sawdust and rice hulls have lower calorific value than coffee grounds. As their content increases, moldability and durability improve, but the calorific value of solid fuels deteriorate. When the amount of these additives is reduced, the durability is weak, There is a problem of losing value.

In order to solve this problem, the present invention produces a solid fuel using a pine cone as a bio raw material satisfying a calorific value while increasing moldability and durability of a coffee bean.

The coffee bean is a porous material including lignin and cellulose, which are the main components of the plant, since it is the remaining residue after heating the coffee bean, which is vegetable, to a temperature above a certain temperature and extracting the coffee stock solution from the finely crushed powder.

Therefore, the coffee bean is excellent in the air permeability due to the tissue characteristics of the plant cell, and it is possible to continuously generate heat for a predetermined time or more through constant compression molding. Since it is residual after hot water extraction, it contains moisture of about 80% or more. It is required to reduce the moisture content of the foil as low as possible.

The pine cones are mainly composed of lignin, cellulose and hemicellulose, and contain about 30% moisture. Therefore, it is necessary to lower the moisture content of the pine cone to use it in solid fuel.

First, the pine cones are pulverized and powdered, then mixed with the coffee beans and dried.

The drying method is not particularly limited and may be any drying method applicable to the drying of coffee bean and pine cone powder. Usually, coffee beans and pine cone powder are dried at a temperature of 100 to 120 ° C for 1 to 4 hours, And the pine cone powder can be adjusted to a range of 2 to 5 wt%, and the moisture content is most suitable in terms of enhancing the moldability in compression molding, and is also advantageous in that it is used for fuel.

As the blend of coffee bean and pine cone powder increases, the calorific value decreases and the moisture content increases such as sawdust and rice husk. As the pine cone is higher in calorific value than sawdust and rice husk, It is preferable to add the minimum amount within the range that can satisfy the molding and durability of the solid fuel.

The mixing ratio of the coffee beans and the pine cone powder is preferably from 60 to 80% by weight of the coffee beans and from 20 to 40% by weight of the pine cone powder. If the coffee bean is less than 60% by weight, the calorific value is lowered. Durability becomes insufficient.

Next, the mixed powder is press-molded at a pressure of 1800 to 2200 kgf / cm 2 to produce a solid fuel, and if less than 1800 kgf / cm 2, the molding is defective or easily broken.

However, when a solid fuel is prepared by mixing a coffee bean and a pine cone powder, smoke is produced more than coffee bean and sawdust mixed solid fuel, which may be restricted depending on the use place.

It is preferable to add water talc powder to the mixed powder of coffee bean and pine cone powder as a method for reducing the fume of the mixed coffee bean and pine cone powder.

Water talc is also called brucite and contains a large amount of magnesium hydroxide (Mg (OH) ₂ ). Magnesium hydroxide reduces the smoke density of the flame and reduces the fume reduction effect of coffee flour-pine cone powder solid fuels. Can be obtained.

In addition, when magnesium hydroxide is left in the air, it absorbs carbon dioxide and is converted into magnesium carbonate (MgCO ₃ ). Magnesium carbonate increases the strength of the solid fuel to improve the durability. Magnesium is converted to magnesium oxide (MgO) and magnesium oxide improves durability by curing the solid fuel due to its hardenability.

In addition, magnesium hydroxide and magnesium carbonate are flame retardant, providing the effect of increasing the burning time by delaying the heat release rate of the coffee bean and pine cone powder mixed solid fuel.

The talc powder is preferably added in an amount of 3 to 7 parts by weight to 100 parts by weight of the powder mixture of coffee beans and pine cone powder. When the amount is less than 3 parts by weight, the effect of reducing fuming is insufficient. When the amount is more than 7 parts by weight, .

Therefore, in order to heat the solid fuel in a short time, it is preferable to add a small amount within the range of the added amount of the talc powder to increase the heat slowly or to increase the durability over a long period of time Do.

The coffee ground solid fuel of the present invention is completely burned in a normal environment and does not generate noxious gas such as carbon dioxide but is in a poor storage condition to absorb moisture or incomplete combustion depending on the combustion environment to generate carbon dioxide.

Therefore, in case of incomplete combustion, it is desirable to remove carbon dioxide. To this end, calcium hydroxide (calcium hydroxide) powder may be added to the mixed powder.

Calcium hydroxide can be obtained by dissolving calcium oxide in water and reacts with carbon dioxide to produce calcium carbonate, so that carbon dioxide generated during incomplete combustion of solid fuel can be removed.

When the talc powder is added to the solid fuel together with the calcium hydroxide powder, when the solid fuel is burned, the magnesium hydroxide of the talc is converted to magnesium oxide and the magnesium oxide has the function of the reaction retardant, so that the calcium hydroxide and the carbon dioxide react rapidly The calcium hydroxide can continuously remove carbon dioxide.

In addition, when the talc powder is added to the solid fuel, calcium oxide (burnt lime) powders may be used instead of the calcium hydroxide powder. In the course of converting the magnesium hydroxide of the talc into magnesium oxide, water is produced, And reacts with carbon dioxide after being converted into calcium hydroxide. In addition, calcium oxide generates a large amount of heat while reacting with water, so that the effect of increasing the calorific value of the solid fuel can be obtained.

The addition amount of the calcium hydroxide powder or the calcium oxide powder is preferably 1 to 5 parts by weight to 100 parts by weight of the mixed powder of the coffee bean and the pine cone powder. When the amount is less than 1 part by weight, the effect of removing carbon dioxide is insignificant. Thereby reducing the ignition property.

Hereinafter, the present invention will be described in more detail with reference to the following examples.

It is to be understood, however, that the invention is not to be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Will be apparent to those skilled in the art to which the present invention pertains.

≪ Example 1 >

The pine cones were mixed with the coffee beans, and the sawdust and pine needle powder were mixed with the coffee bean instead of the pine cone powder for comparison.

The mixing ratios of the pine cone powder, the sawdust and the pine needle powder were adjusted in the range of 0-100 wt% and 10 wt%, respectively, in the coffee bean (Table 1), and the mixture was dried at 100 ° C for 150 minutes, Respectively.

The compression molding was made into a cylindrical shape using a high pressure without making it into a general pallet shape, and the mixture was pelletized in a pellet die having an inner diameter of 40 mm using a press (Atlas Autotouch 25T Press, Specac, UK) And compressed to 5, 10, 15, 20, and 25 ton, respectively, to produce solid fuel.

As a result of compression molding, the compression of 5 ~ 20 ton was not easily formed, some molding was easily broken but the molding was good at 25 ton and some shape was maintained after molding.

<Test Example 1> Moisture content, ash, calorific value analysis

Samples of the respective groups of Example 1 were submitted to Daeduck Research Institute, Inc. for comparison and analysis of water content, ash and calorific value, and the results are shown in Table 1 and Figs.

Moisture content, ash, calorific value analysis result mixture Name of sample Mixing ratio (% by weight) Moisture content
(weight%) Ash
(weight%) Calorific value
(㎈ / g) Coffee shop Sawdust / pine needle powder
/ Pine cone powder Coffee break +
sawdust One 100 0 3.18 2.38 5639 2 90 10 3.99 2.25 5542 3 80 20 5.66 2.20 5489 4 70 30 6.94 1.99 5380 5 60 40 8.70 1.81 5347 6 50 50 9.57 1.68 5242 7 40 60 11.0 1.47 5093 8 30 70 12.3 1.32 4992 9 20 80 13.7 1.20 4940 10 10 90 15.0 1.09 4855 11 0 100 16.4 0.94 4774 Coffee break +
Pine leaf powder 12 90 10 3.31 2.36 5595 13 80 20 3.33 2.26 5552 14 70 30 3.28 2.19 5497 15 60 40 3.30 2.11 5448 16 50 50 3.16 1.97 5367 17 40 60 3.20 1.91 5316 18 30 70 3.17 1.81 5112 19 20 80 3.14 1.73 5231 20 10 90 3.23 1.64 5197 21 0 100 3.03 1.53 5008 Coffee break +
Pine cone powder 22 90 10 3.49 2.40 5596 23 80 20 3.46 2.37 5519 24 70 30 3.59 2.39 5499 25 60 40 3.56 2.38 5450 26 50 50 3.67 2.47 5448 27 40 60 3.60 2.48 5336 28 30 70 3.79 2.41 5306 29 20 80 3.60 2.34 5251 30 10 90 3.77 2.30 5223 31 0 100 3.97 2.31 5188

As shown in Table 1, water content, ash and calorific value according to the blending ratio of coffee bean, sawdust, pine needle powder and pine cone powder were compared with each other. As a result, when the coffee bean was used at 100%, the water content was the lowest and the calorific value was the highest. As the amount of sawdust, pine needle powder, and pine cone powder increases, the calorific value decreases gradually.

Therefore, it is preferable to keep the content of coffee beans as high as possible in the solid fuel in terms of heat generation. However, in this case, the mixing amount of sawdust, pine needle powder and pine cone powder is relatively small.

4 shows the state of the solid fuel produced by press-molding a pellet die having an inner diameter of 40 mm at a mixing ratio of coffee bean and sawdust with a force of 25 ton. In the case of 100% coffee bean to 100% sawdust, , But it was easily broken even with small external force as the content of coffee bean increased, and durability was not sufficient.

Sawdust powder, pine needle powder, and pine cone powder were compared to each other. As a result, the moldability of pine needle powder, pine needle powder and sawdust were superior to those of pine needle powder and pine needle powder. It can be seen that mixing the pine cone powder with a coffee bean and then compression molding is the most advantageous in terms of calorific value and moldability.

Accordingly, it is most preferable to mix 60 to 80% by weight of the coffee bean and 20 to 40% by weight of the pine cone powder, which have a low water content and a low ash content and a high moldability and durability, .

&Lt; Example 2 >

The talc powder, the calcium hydroxide powder and the calcium oxide powder were mixed in the mixed powder prepared by mixing the coffee bean and the pine cone powder at the time of preparing the sample 24 (70% by weight of coffee bean and 30% by weight of pine cone powder) And compression molded to produce a solid fuel.

Compounding ratio (% by weight) Name of sample Mixed powder Talc powder Lime powder Quicklime powder 32 95 5 - - 33 97 - 3 - 34 97 - - 3 35 92 5 3 - 36 92 5 - 3

&Lt; Test Example 2 >

The smoke densities of the samples 24 and 32 to 36 were measured and the maximum smoke density was analyzed by applying a non-flaming type horizontal test to a smoke density tester (Smoke Density Chamber SB2005, FESTEC, Korea).

The specimens were cut to a size of 75 × 75 mm, ignited by a heating furnace, adjusted to a heat flux density of 25 ㎾ / ㎡, and then measured for 1200 seconds. The results are shown in Table 3 below.

Smoke density measurement result Name of sample Maximum smoke density (Ds) 24 468 32 374 33 393 34 435 35 359 36 364

In Table 3, the maximum smoke density of the sample 24 in which 70% by weight of coffee beans and 30% by weight of the pine cone powder are mixed is 468 Ds, and the sample 32 to which the talc powder is added is 374 Ds and the lime (calcium hydroxide) Was measured as 393 Ds.

It can be seen from the result that the maximum smoke density is lowered in Sample 32 (adding water talc powder to the solid fuel), magnesium hydroxide contained in the water talc has an effect of lowering the smoke density of the flame, and addition of calcium hydroxide to the solid fuel ) Is effective in lowering the smoke density.

In case of sample 34 (adding lime powder to solid fuel), there was a slight decrease in maximum smoke density. In compression molding in press, calcium oxide (calcium oxide) reacts with a small amount of water contained in solid fuel, And the slaked lime is considered to have lowered the smoke density.

Sample 35 with the addition of talc powder and calcium hydroxide powder showed the highest smoke density at 359 Ds with the largest smoke density. This is because the magnesium hydroxide contained in the talc was converted to magnesium oxide by combustion and the calcium hydroxide and carbon dioxide And the smoke is effectively removed.

The sample 36 containing the talc powder and the quicklime powder was converted into calcium hydroxide by reacting the water produced in the course of the conversion into magnesium hydroxide magnesium dioxide of talc and reacted with the quicklime, thereby exhibiting a smoke- .

As described above, it can be seen that the smoke generated by the combustion of the coffee beans and the pine cone powder can be reduced by adding the talc powder, the calcium hydroxide powder and the calcium oxide powder to the coffee beans and the pine cone powder.

Claims (7)

Crushing and pulverizing the pine cones;
Mixing 60 to 80% by weight of a coffee bean with 20 to 40% by weight of the pine cone powder and drying at a temperature of 100 to 120 ° C for 1 to 4 hours to a moisture content of 2 to 5% by weight;
Adding 3 to 7 parts by weight of talc powder and 1 to 5 parts by weight of calcium oxide powder to 100 parts by weight of the dried mixed powder; And
And press-molding the mixed powder to which the talc powder and the calcium oxide powder are added at a pressure of 1800 to 2200 kgf / cm &lt; 2 &gt;. delete delete delete delete delete delete

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