JP2019502013A - Biofuel - Google Patents

Abstract

The present invention relates to a biofuel containing coffee grounds, in particular an advanced solid biofuel.

Description

The present invention relates to the use of biomass, including biofuels (“biofuels”), particularly those produced in instant coffee factories (“ICFs”) as advanced solid biofuels, among which coffee extraction residue (“WCG”). ) Regarding the use of.
Biofuels can be provided, for example, as WCG derived biomass pellets ("pellets") and WCG derived biomass briquettes ("briquettes"). The present invention provides the biofuel itself, as well as a method and apparatus for producing biofuel.

WCG is a kind of biomass. Biomass is an organic material produced by the reaction between carbon dioxide in the air, water, and chlorophyll through photosynthesis to produce carbohydrates.
Agricultural crops absorb solar energy through photosynthesis. Solar energy is stored in the form of chemical energy in a combination of biomass components. The energy stored in this conjugate can be released by burning the biomass and digesting the plant to ingest nutrients contained in the biomass's carbohydrate structure.

There are various types of biomass, consisting of many different sources, including trees, leaves, and other plant materials.
The inventor has discovered that WCG-derived biomass is a more effective and equivalent biofuel than woody biomass. WCG biomass has a main chain of carbon, hydrogen, and oxygen molecules. These components are chemically combined with each other to form a lignocellulose structure.

For centuries, wood has been burned to provide a heat source and biomass has been used to generate energy.
Other biomass can be converted to various solid, liquid, or gaseous biofuels for various applications as wood replacements. This depends on the conversion process used.

  According to the UK Bioenergy Strategy (DEFRA, 2012), bioenergy supplied while maintaining the environment will contribute to approximately 8-11% of primary energy demand across the UK by 2020. Has been. Similar levels of contribution can be expected in other countries.

There are significant initiatives in the UK that encourage the uptake of solid biofuel combustion, including feed-in tariffs for renewable energy (“FiT”) and renewable heat incentives (“RHI”).
As a result, many household, commercial and industrial scale biomass fired boilers have been installed, operated and ingested on a large scale throughout the UK.
At present, most small scale biomass boilers use wood pellets or wood chips.
The highest current standard in internationally recognized wood pellets is ENplus, including ISO 17225-2: 2014 (formerly ISO 1491-2). This standard then specifies the properties required to make an effective wood pellet.
This standard includes properties such as size, moisture content, ash content, mechanical durability, fine particles, true calorific value, bulk weight, ash melting behavior and elemental composition.

European Patent Application Publication No. EP0962515

It would be advantageous to provide a solid biofuel that replaces what is currently available. It is particularly advantageous to provide an alternative to wood pellets used in biomass boiler systems.
The inventor has confirmed that this type of pellet can be made from waste (eg, WCG).
Previously, WCG was considered unusable to produce pellets or briquettes that would burn in biomass boilers, stoves, etc. due to its high oil content. In the processes used to produce pellets and briquettes, it is very difficult in the prior art to form pellets or briquettes from compositions containing more than about 8% oil or fat.
However, the inventors have developed pellets and briquettes that contain high levels of WCG and are durable. The invented pellets and briquettes contain 20% to 25% fat. Pellets and briquettes have also shown that natural biofuels meet the relevant UK ISO standards (non-wood solid biofuel (pellets): ISO 17225-6: 2014; and non-wood solid biofuels (briquette): ISO) 17225-7: 2014).

  European Patent Application Publication No. EP0962515 describes a burnable biofuel log containing at least 50% WCG. The log further includes a flammable binder (eg, solid paraffin), a carrier, usually sawdust, and a caulking agent (eg, starch or molasses). The logs described in the above patent application documents contain about 35% binder. This type of log is not suitable for use in a biomass boiler because the ash (amount) produced by burning the log quickly fills the boiler. When using logs on a stove installed in a fireplace, there may be problems with ashing. And it is necessary to clean the ash regularly.

Instant coffee is one of the most popular drinks in the world. There are hundreds of ICFs around the world, and a total of millions of tons of instant coffee extraction residue ("IWCG") is discharged each year. IWCG is difficult to store and transportable to dispose of. When discharged, IWCG contains moisture. When IWCG containing water is stored, the growth of fungi and bacteria is promoted. IWCG drying requires significant energy input, but may not be desirable from a cost standpoint.
Furthermore, because IWCG tends to ignite spontaneously, there is some risk in storing dry IWCG. Since IWCG has a high water content, direct incineration makes the work expensive and inefficient. And it requires a complete, continuous 24/7/365 treatment (24 hours, 7 days, 365 days).
In addition, machines (fluidized bed boilers) that are sometimes used when incinerating IWCG are expensive to construct, install, and very inefficient, expensive to operate and complex. In fact, a team of highly experienced engineers and operators is often required.
For this reason, IWCG is used as a solid biofuel prior to an efficient, stable and easy-to-operate combustion process, thus processing the IWCG emitted by the ICF so that it can be stored and transported easily It would be advantageous to provide a cost effective and environmentally beneficial method for doing so. It is beneficial to burn this solid biofuel in a conventional biomass boiler to generate heat, steam and power to ensure efficient, cost effective and easy operation of the system.

ICF ranges in size from factories that emit more than 200 kt of IWCG annually to factories that process less than 5 kt of IWCG annually. Due to the large, obsolete, inflexible work, local waste management practices, and the inconsistent, waste disposal infrastructure that only works in that location, there are solutions to process the discharged IWCG. not exist. And the scale can potentially be 40 times this.
As a result, IWCG is processed differently from the scenario. And usually this waste is sent to a landfill or incinerator, which wastes both the ICF and the environment. IWCG does not work well in anaerobic digestion because of its low biomethane potential and because of its low protein, grainy nature and particle size.

A large amount of energy (heat, steam, and power) is required to operate an ICF.
At present, most of this energy comes from conventional fossil fuels. Only a small portion of this energy is recovered where IWCG is incinerated. Even when IWCG is dried, it still retains a high calorific value (“CV”). If the CV can be captured and stored for energy production at the discretion of the ICF, it would be environmentally and commercially advantageous.
By using IWCG as a biofuel, ICF itself can supply a large amount of useful energy to ICF, and in some cases, the amount of biofuel produced can reduce the amount of energy consumed by ICF. May exceed.

In many countries, biomass-based fuels need to meet government-set criteria for emissions (especially CO_2, NO_x, and particulate matter), such as those established by the UK RHI.
It would be advantageous to be able to produce biofuels that meet as many standards as possible and that can be tailored to meet the relevant standards in the country of use.

The inventor has confirmed that solid biofuel can be prepared from IWCG.
Previously, because IWCG has a high oil content (IWCG and WCG compositions typically contain 20-25% fat) and the material does not contain fiber, it is not possible to utilize IWCG to produce solid biofuels. It was considered impossible.
Particularly in the process used to make solid biofuel from biomass, it is very difficult in the prior art to form solid biofuel from compositions containing more than about 8% oil or fat. .
Furthermore, because IWCG is very uniform, large in size and contains highly elastic particles, it is more difficult to produce a solid biofuel with high mechanical durability.
Larger particle sizes increase the possibility of cracking. Further, the bond between the fine particles is increased by mechanical entanglement, and the distance between the particles is eliminated. Therefore, it becomes very easy to pelletize WCG with a mixture of particle sizes.
Furthermore, the range of treatments applied during the production of instant coffee usually means that oils that are kept at the cellular level may be released, and the starch contained in the residue is gelatinized. This makes it more difficult to bond the particles together.
However, the inventor has developed a solid biofuel with a suitable chemical composition, a high level of mechanical durability, and a high CV.

  The first aspect of the invention provides a combustible biofuel composition comprising WCG.

  The term “WCG” means spent coffee grounds that remain after brewing coffee with ground and roasted coffee beans. Any coffee grinder can be used and can include those produced by espresso, filters, and other coffee making methods (eg, instant coffee making).

  The composition is preferably in the form of pellets or briquettes and is typically used for combustion in a biomass boiler system. This type of boiler system is known in the art, but is usually operated mainly with wood based biofuels (eg wood pellets, chips and logs).

Typically, the WCG contained in the composition is at least 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%.
When the composition is a pellet, the WCG contained in the composition is typically at least 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%. When the composition is a briquette, the WCG contained in the composition is typically at least 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%.

  The content (content) of the composition is preferably based on the composition itself, rather than on the raw materials used to produce the composition. However, the characteristics of the composition may also apply to the raw materials.

The composition may further comprise a flammable filler (filler agent). The filler is typically a high calorific material. The filler may be solid, and when it is solid, it is usually fibrous. Nitrogen contained in the filler is usually less than WCG, and helps to minimize NO _x emissions generated during the combustion of biofuels.
In addition, the filler may be of plant origin and is usually organic waste such as barley waste, hop waste, cocoa husk, sugar beet, straw, wood, nut husk, reed, bread crumbs, corn, wheat husk, barley Rice husk).
In the examples, the filler is sawdust. When the filler is sawdust, it is sawdust made from soft or hard wood. Softwood sawdust is preferred in some embodiments because softwood sawdust contains more lignin than hardwood sawdust.
When the filler is sawdust, it can be crushed using, for example, a hammer mill or a pin wheel mill. Other fillers can also be crushed with, for example, a hammer mill or a pin wheel mill.
The particle size of the filler can be selected to enhance durability. For example, the particle size of the filler may specifically be the maximum average length or less than 2 mm, less than 1.5 mm, less than 1 mm, less than 0.75 mm, less than 0.5 mm. The filler can be crushed or processed to this particle size.

The filler included in the composition is typically at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or 55% .
In some examples, the filler included in the composition is less than 30%, 25%, 20%, 15%, 10%, 7.5%, or 5%.

  When the composition is a pellet, the filler included in the composition is typically 0% to 30%, 5% to 25%, 10% to 25%, or 15% to 25%. Alternatively, the filler included in the composition may be at least 10%, more typically at least 15%, more typically at least 20%, and even more typically at least 22%. The filler included in the composition is typically less than 30%. This is especially the case when the filler is sawdust.

  When the composition is a briquette, the filler included in the composition is typically 0% to 50%, 5% to 50%, 10% to 50%, or 15% to 50%. Alternatively, the filler included in the composition may be at least 10%, more typically at least 15%, more typically at least 20%, and even more typically at least 25%. This is especially the case when the filler is sawdust.

  Inclusion of combustible components maximizes the output that generates heat while allowing the amount of emissions generated when burning biofuel to be controlled within a desired range.

The composition can further comprise a binder. The term “binder” as used herein refers to ingredients added to the composition to enhance the pelletizing or briquetting ability of the composition or to increase the durability of the once pelleted or briquetted composition. Means and is used.
The binder is particularly useful when the composition is in pellet form. The pellets must have sufficient mechanical durability so that they remain substantially complete during storage, transportation and boiler use. In some cases, durability can affect emissions. When the durability is low, dust and fine powder are released as a result.

A binder can be selected to provide the desired level of durability while preventing unwanted emissions from increasing as the pellets are burned. The binder can be or include, for example, a surfactant, an emulsifier, or a gelling agent. Possible binders include polysaccharides (eg, sticky or starch), glycerol, natural paraffin, vegetable oil, lignosulfonate, molasses (molasses) and the like.
The binder may be selected depending on the amount and type of oil in the WCG. For binders useful in this type of composition, the hydrophilicity or lipophilicity may be rather low. The hydrophilic-lipophilic balance of binders (especially surfactants) is measured on the HLB scale.
Binders that are particularly useful in compositions with low WCG oil content are found at the lower end of the HLB scale. If the oil content increases, a binder further on the scale may be more appropriate.

  The binder included in the composition is typically at least 0.5%, 0.75%, 1%, 1.5%, or 2%. The binder included in the composition is typically about 10%, 7.5%, 7%, 6.5%, 6%, 5.5%, or 5% or less. The composition can include a plurality of binders. In that case, the binder contained in the composition is typically about 10%, 7.5%, 7%, 6.5%, 6%, 5.5%, or 5% or less overall.

  When the binder is glycerol, the glycerol contained in the composition is typically about 1 to about 7.5%, more typically about 2.5 to about 7.5%, more typically Is about 4 to about 6%, even more typically about 5%.

  When the binder is lignosulfonate, the lignosulfonate included in the composition is typically about 3% or less to avoid excessive sulfur release.

  When the binder is paraffin, the paraffin contained in the composition is typically about 10% or less, particularly about 5% or less.

  When the biofuel is in the form of a solid or compressed structure (eg, pellets, briquettes, or packs), it may be preferable to use a binder other than paraffin. The temperature that is ideal for preparing pellets or briquettes for maximum durability is too low for solid paraffin. Thus, in the examples, the binder is not solid paraffin.

  When the composition is in the form of a pellet, the pellet is generally cylindrical. The diameter of the composition is typically about 4-8 mm, more typically about 5-7 mm, and even more typically about 5.5-6.5 mm. The length of the pellet is typically about 30-50 mm, more typically about 35-45 mm.

If the composition is in compressed form, especially if it is in the form of a briquette, it can further comprise a dressing.
The dressing may consist of any suitable combustible material (eg, wax or resin). Specifically, the coating material may be solid paraffin. The covering material may be applied by any suitable method such as dip coating or spray coating.

  The composition can include one or more additives.

  The second aspect of the present invention provides a raw material composition suitable for use in making the composition of the first aspect of the present invention.

The third aspect of the invention provides a method for producing a solid biofuel composition comprising WCG. The method comprises the following steps.
a) providing a raw material composition according to the second aspect of the invention b) compressing the raw material into pellets or briquettes

  Providing the raw material composition can comprise providing a WCG.

  The step of providing the raw material may comprise the step of decontaminating the WCG to remove unnecessary contaminants, such as plastic or paper.

  Providing the raw material composition can comprise drying the WCG. Any suitable method can be used for drying. (For example, drying in a rotary dryer, industrial centrifuge, microwave vibration drying, mechanical press, or natural drying). The raw material composition is typically dried to a moisture content of 6-20%.

  Providing the raw material can also include sieving the WCG to remove small contaminants that escaped in the decontamination step.

  Providing the raw material composition can comprise mixing WCG with one or more other components, such as a binder or filler.

  The method can also comprise agitating the ingredients to avoid any obstructions.

  When making a raw material into a pellet, the step of compressing the raw material can include a step of pressing the raw material by a pellet press. The pellet press may be an appropriate press. For example, a die having a bore hole for pressing the raw material can be provided. When the raw material is passed through the press, several long compressed biomass compositions are produced which can then be cut into pellets. The method according to the invention may comprise the step of controlling the temperature of the pellet press.

  The method according to the invention can also comprise the step of cooling the pellets or briquettes. Cooling can increase the mechanical durability of the pellets or briquettes.

  The pellets or briquettes can then be screened, for example by sieving to remove pellets or briquettes that are not of the desired size. Any dust or particles that are removed from the pellets or briquettes can be returned to the manufacturing process, for example by adding them again to the raw material during the process.

  A fourth aspect of the present invention provides an apparatus for preparing biofuel from WCG biomass. The apparatus of the present invention comprises means for drying the WCG, means for mixing the WCG and one or more additives to produce the raw material, and means for compressing the raw material.

  The means for drying the WCG can be any dryer (eg, rotary drum dryer industrial centrifuge, microwave vibration drying, mechanical press, or natural drying).

  The means for compressing the raw material may be a die and the raw material is pressed through a bore hole in the die. The raw material can be pressed through a die by a roller, whereby the raw material is pressed into the borehole.

  The apparatus can further comprise means for decontaminating the WCG to remove unwanted contaminants. The decontamination means may be a trommel or other suitable method for sorting materials by size.

  The fifth aspect of the present invention provides a biofuel composition comprising WCG. In an embodiment, the IWCG contained in the WCG is at least 50%.

  As indicated in connection with the first aspect of the present invention, the term “WCG” means spent mash that remains after brewing coffee with ground and roasted coffee beans. WCG can include strawberry from ICF and espresso, filter, and other coffee making methods.

  The WCG contained in the biofuel of the fifth aspect of the invention is typically at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, 50%, at least 55%, at least 60%, At least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or about 100%.

The term “IWCG” means spent mash that remains after brewing instant coffee (also known as soluble coffee) with ground and roasted coffee beans in a spray-dried or freeze-dried instant coffee mill.
Biofuel WCG typically has at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% IWCG. %, At least 98%, or about 100%.

  The IWCG contained in the biofuel of the present invention is typically at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65% , At least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or about 100%.

  The content (content) of the composition is preferably based on the composition itself, not the raw materials used to produce the composition. However, the characteristics of the composition may also apply to the raw materials.

  The biofuel of the fifth aspect of the present invention is typically solid. Specifically, it is typically in the form of pellets, briquettes, packs or other compressed solid structures.

  The true calorific value of the biofuel of the present invention is preferably about 16 to 24 MJ / kg, more preferably about 17 to 23 MJ / kg, and still more preferably about 18 to 22 MJ / kg.

  The composition can further comprise a binder. As used herein, the term “binder” is added to a composition to enhance the ability of the composition to be compressed into a solid with sufficient durability to store and / or transport the composition. Means and is used as a component.

The particle size of IWCG tends to be very uniform. This makes it somewhat unpredictable that the coffee grinder can be compressed into a durable solid, but the inventor has confirmed that it can be compressed into a durable solid.
In the first aspect of the present invention, a binder can be used to increase durability.
Durability also has a very large impact on emissions. Low durability usually releases dust and particulates, resulting in large amounts of soot, particulate matter and ash, and the risk of incomplete combustion and explosion.
The binder can be or include, for example, a surfactant, an emulsifier, or a gelling agent. Examples of possible binders include those defined with respect to the first aspect of the invention, or polysaccharides (eg viscous substances or starches), glycerol, natural paraffin, vegetable oils (eg coffee oil), ligno Examples thereof include sulfonates and molasses (molasses). The binder can be selected according to the amount and type of oil in the IWCG. For binders useful in this type of composition, the hydrophilicity or lipophilicity may be rather low. The hydrophilic-lipophilic balance of binders (especially surfactants) is measured on the HLB scale.
Binders that are particularly useful in compositions with low WCG oil content are found at the lower end of the HLB scale. If the oil content increases, a binder further on the scale may be more appropriate.

If the biofuel is in the form of a solid or compressed structure (eg pellets, briquettes or packs), it may be preferable to use a binder other than paraffin.
The temperature that maximizes durability and is ideal for preparing pellets or briquettes is too cold to use solid paraffin. Thus, in one embodiment, the binder is not solid paraffin.

  The biofuel can further include an oxidizing agent such as sodium nitrate or potassium nitrate.

The binder included in the composition is typically at least 0.5%, 0.75%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4% 4.5%.
The binder contained in the composition is typically about 10%, 7.5%, 7%, 6.5%, 6%, 5.5%, 5%, 4.5%, 4%, 3% .5%, 3%, 2.5%, 2%, 1.5%, or 1% or less.
The composition can include a plurality of binders. In this case, the binder contained in the organism is typically about 10%, 7.5%, 7%, 6.5%, 6%, 5.5%, 5%, 4.5% overall. 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, or 1% or less.

As in the first aspect of the invention, the composition may further comprise a flammable filler. Typically, the filler is a material with a high net calorific value and can be as defined for the first aspect of the invention. It may be solid, and if it is solid, it is usually a fiber. Optionally, the filler may be plant-derived, and typically organic waste (eg barley, hop, cocoa, sugar beet, straw, wood, nuts, reed, bread, corn, wheat Rice husk, barley rice husk).
In one embodiment, the filler is a coffee chaff. The term “coffee chaff” means the silver skin that leaves the coffee beans after roasting. Silver skin is the thin inner skin (endothelium) of green (raw) coffee beans that remains after threshing / milling the beans.
In other embodiments, the filler is sawdust. In another embodiment, the filler is bean hulls. The filler included in the composition is typically 60%, 55%, 50%, 45%, 40%, 35% 30%, 20%, 25%, 15%, 10%, 7.5%, 5% %, 4%, 3%, 2%, and less than 1%. The particle size of the filler can be selected to enhance durability. For example, the particle size of the filler may in particular be the maximum average length or less than 2 mm, less than 1.5 mm, less than 1 mm, less than 0.75 mm, less than 0.5 mm. The filler can be crushed or otherwise processed to this particle size.

Because it contains a filler, other waste from ICF (especially coffee chaff) can be utilized for biofuel. By the above, CV of biofuel can be changed according to the filler added. In addition, the inclusion of the filler makes it possible to control the amount of emissions generated when the biofuel burns.
For example, in order to meet emission requirements set by the Administration, if is possible to reduce NO _x emissions level is advantageous, may include nitrogen content is less filler than IWCG (such as sawdust). Many governments currently set standards for fuel emissions based on emissions of NO _x , carbon dioxide, particles, and the like. It would be advantageous to provide a compact, clean fuel combustion with a low level of particulate emissions.

The composition can include one or more additives (eg, processing agents). The processing agent may be a hydrophilic agent that can improve biofuel binding. Further, the processing agent may be an agent that assists in compressing the biofuel, for example, an agent for improving the passage of the biofuel through a die or pellet forming head. It can also reduce solid biofuel cracking and can further assist cooling. The processing agent may be starch (eg, flour).
Where the processing agent also assists in binding, the composition can include additional binders, or the composition can simply include the processing agent.

  If the composition is in compressed form, for example in the form of pellets or briquettes, the composition can additionally comprise a dressing. The dressing may be made from any suitable combustible material (eg, wax or resin). Specifically, the coating material may be solid paraffin. The dressing may be applied by any suitable method (eg, dip coating or spray coating).

  The sixth aspect of the present invention provides a raw material composition suitable for producing the composition of the fifth aspect of the present invention. The feedstock typically includes the same components as the biofuel of the present invention.

Also provided by the seventh aspect of the present invention is a method for producing a solid biofuel composition comprising WCG (particularly IWCG). The method comprises the following steps.
a) providing a feed composition according to the sixth aspect of the invention b) compressing the feed into solid biofuel

Providing the raw material composition can comprise providing WCG (particularly comprising or consisting of IWCG).
WCG contained in the raw material is typically at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, At least 90%, at least 95%, at least 98%, or about 100%.

  The WCG contained in the biofuel typically comprises IWCG at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, At least 95%, at least 98%, or about 100%.

  Thus, the IWCG contained in the feed is typically at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70% , At least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or about 100%.

  The method according to the present invention may include the step of decontaminating the raw material to remove unwanted contaminants.

The method according to the invention can comprise a step of drying the raw material. The raw material composition is typically dried to a moisture content of 6-20%.
For drying, any fluidized bed dryer, stirred underflow dryer, rotary dryer, industrial centrifuge, microwave vibration dryer, mechanical press, screw press, or natural air drying Appropriate methods can also be used.
The amount of energy required to efficiently dry the IWCG is significantly lower than the amount required to dissipate the wet IWCG water, so rather than simply trying to burn the wet IWCG Is advantageous.

The step of drying the raw material itself may include a preliminary drying step and a drying step. In the preliminary drying step, water removal can be performed using a centrifuge, a drying bed, a dewatering press, or utilizing composting in a container.
The pre-drying step can comprise storing IWCG and generating self-heating by utilizing bacterial or fungal growth. A sedimentation tank can further be used to remove suspended solids from the water. In the pre-drying step, up to 30%, 40% or 50% of moisture can be removed.
It is advantageous to incorporate a pre-drying step. This is because this pre-drying step can remove a significant amount of water in a low energy intensity step. The drying step may be significantly higher in energy intensity than the pre-drying step.
Combining these two steps reduces the overall amount of energy used to dry the IWCG.

  The method according to the invention can also include the step of extracting coffee oil from the IWCG. The step of extracting coffee oil can comprise centrifuging the IWCG. A step of extracting coffee oil may be performed after drying the IWCG or between the pre-drying and drying steps. The method can further include purifying the extracted coffee oil.

  The method according to the present invention may also include the step of combining IWCG with one or more other components (eg, fillers).

  The method according to the invention can also comprise a step of adjusting the raw material. The conditioning step can comprise treating the raw material with steam. The steam may be humid or dry steam. The adjusting step may comprise a step of adding a binder to the raw material.

  The step of compressing the raw material can comprise a step of packing or pelletizing the raw material and extruding (briquetting).

  The method according to the invention can also include the step of cooling the compressed feedstock.

  The method according to the invention can also comprise the step of screening the compressed raw material, for example by sieving to remove pellets, packs or briquettes which are not of the desired dimensions. Any dust or particles removed can be returned to the manufacturing process, for example, by adding it back into the raw material during the process.

  Using the solid biofuel produced by the method of the present invention or biodiesel from the coffee oil extracted by the method of the present invention, the method according to the present invention may also comprise the step of supplying fuel to the dryer. it can.

  The method according to the invention can also include the step of recovering heat from any other step (especially the drying or pre-drying step) of the method of the invention.

  The eighth aspect of the present invention provides an apparatus for preparing biofuel from IWCG. And an apparatus is equipped with the means for drying IWCG, and the means for compressing a raw material.

  The means for drying the IWCG may be any dryer (eg, a rotary drum dryer, an industrial centrifuge, a microwave vibration dryer, or a mechanical press).

  The apparatus according to the present invention can also be provided with a preliminary drying means (for example, a centrifuge, a dehydrating press, or a drying bed) for performing preliminary drying of the raw material.

  In order to adjust the raw material, the apparatus can also comprise adjusting means.

The means for compressing the raw material may be a die having a bore hole that presses or extrudes the raw material. The raw material can be pressed by a roller with a die, and the raw material is pressed into the borehole.
Alternatively, the means for compressing the raw material may be a cold press, block press, or any other device that can compress the raw material into a solid (especially a pack, pellet, or briquette).

  The device according to the invention can also comprise sorting means (for example a sieve) for sorting biofuel.

  The apparatus according to the invention can further comprise heat recovery means for recovering heat from other parts of the apparatus.

  The device according to the invention can be tuned for use with ICF.

  The present invention further provides an ICF comprising an apparatus according to the eighth aspect of the present invention.

  The invention will now be described in detail by way of example with reference to the drawings.

The particle size distribution of different coffee types is shown. The coffee powder measured here is not WCG but before being used as coffee (making coffee). The effect in durability when sawdust is added to the composition is shown. 3a and 3b show the durability over the course of the manufacturing process. 4a and 4b show the durability over the course of the production process of a composition comprising 20% sawdust, 5% lignobond (lignosulfonate) and 75% IWCG.

Example 1
A method for preparing a biofuel composition according to the present invention.
The method according to the invention comprises a series of steps for purifying, drying, mixing and compressing WCG. WCG may or may not include IWCG.

  WCG is purified by placing the material in a trommel and removing plastic and other debris. The material is screened through a rotating cylindrical screen to separate the coffee grinder and large contaminants. Undesirable contaminants are collected and removed.

  Coffee mash coming out of the trommel is sent to a rotary kiln / drum dryer via a conveyor belt. The coffee grounds are dried to the desired moisture content upon mixing to ensure uniform drying.

  The coffee grounds are then placed in a mixing screw and combined with other ingredients contained in the final composition within the mixing screw.

  If the solid biofuel is produced in the form of pellets, the WCG mixture is transferred to a pellet press. It may be agitated before or during the transfer to ensure that the WCG mixture is evenly mixed and helps prevent accumulation of any obstructions or materials.

The pellet press consists of a die ring that goes around a fixed roller. The material is supplied to the roller from the side and pressed from the inside to the outside through the bore hole of the die.
The conditioned material is placed in a pellet press and distributed uniformly. A layer of material is then formed on the running surface of the die.
The roller runs over this layer and presses the material in the die grooves through the die forming the rows of pellets. A long string of pellets coming out of the die is cut to the desired length with a knife.

  The pellets coming out of the pellet press are at a temperature of about 80-120 ° C. and then transferred to a cooler. Cooling enhances the mechanical durability of the pellets.

  After cooling, the pellets are sieved to sort out pellets that do not match the desired dimensions.

  When the solid biofuel is in the form of a briquette or pack, the mixture is transferred from the mixing screw to a compressor and compressed into a briquette or pack by the compressor. Briquettes or packs can also be cooled.

Analysis NO _x emissions inventors of WCG pellets were recognized liquid, solid, and the need to limit emissions of the NO _x generated when burning a gaseous biofuels. In some countries, solid biofuels are required to meet emission standards in order to receive sales and / or government incentives and subsidies.
Although it is generally understood that biofuels containing high nitrogen content components (eg WCG) tend to produce more NOx emissions than biofuels with low nitrogen content, the inventor the relationship of the nO _x emissions and was confirmed not to be linear. The mechanism of NO _x emissions is not fully understood.
The inventors have determined that NO _x emissions are not simply dependent on the nitrogen content of the biofuel, but are influenced by whether the nitrogen is volatilized or whether it remains carbonized after combustion.

WCG contains more nitrogen than other forms of biomass (eg, wood). However inventors, in order to reduce NO _x emissions, and found not only a problem that the WCG may be combined with a low nitrogen content biomass.
NO _x emissions can be controlled by changing the amount of oxygen utilized during combustion. The composition prepared by the present inventor meets the NO _x requirement defined in the ISO standards for pellets and briquettes used in biomass boilers.

Mechanical durability Durability is important because pellets and briquettes must not be damaged during storage and transport.
Durability is particularly important for pellets because poorly durable pellets can be broken down while used in biomass boilers. Machine durability can also affect emissions emissions. When the durability is low, the emission of particulate matter increases due to the generation of dust and fines.

  The inventor prepared WCG pellets and briquettes according to the present invention and tested their durability.

The desired final durability of the pellet is at least 85%. Durability was tested on pellets that had just been produced and were not sieved to remove less durable pellets.
The inventor left the pellets for at least 24 hours after production and sifted the pellets to remove loose material or poorly formed pellets, increasing the overall average durability by about 10% I found it.
It has also been found that the adjustment step increases overall durability. Based on this, the inventor exceeds 70% of the pellets produced in the main factory and 65% of the pellets produced in the mini pelleter at this stage of the test representing pellets that meet the final durability goal. Durability was considered.

Ash The complete thermochemical conversion of WCG (eg combustion in a biomass boiler) leaves a solid residue that is inorganic and is called ash. Biomass ash poses many challenges in behavior during combustion. That is particularly how it relates to slagging and fouling. The ash content of unmixed WCG is very low, 1.8%.

  To measure the initial softening temperature, softening temperature, melting point, and flow temperature, an ash melting test was performed on the ash produced from the pellets. These temperatures indicate the nature of the boiler ash. According to the figure showing the melting temperature of wood biofuel ash, the first deformation occurs at about 1200 ° C.

Calorific Value For use in energy production, one of the most important characteristics of a biofuel is its energy content. There are various ways to represent the energy content of a biofuel. The calorific value is, for example, high calorific value (“HHV”) or total calorific value, low calorific value (“LHV”), or true calorific value “CV”.
Once the combustion product cools and reaches the same temperature as before combustion (usually 25 ° C.), HHV (unit quantity or volume) is the amount of heat produced / released from the complete combustion of the biofuel, Defined.

Most biofuel combustion releases water, which then evaporates in the combustion chamber. The process of evaporating water requires energy. This is known as the latent heat of evaporation.
In most boilers / combustion chambers, water vapor released by combustion is exhausted from the system via the exhaust stream and disappears.
There is an advanced boiler that goes through a second condensation process. And in the second condensation process, the water vapor is condensed, thereby recovering most of the latent heat, which can be used for work.
HHV includes latent heat during evaporation, and the difference between HHV and LHV is equal to the amount of latent heat during evaporation that can be recovered.

The unmixed WCG CV is about 22 MJ / kg, which is significantly higher than the wood CV (wood chip CV: about 12.5 MJ / kg, wood pellet CV: about 17 MJ / kg).
A mixture of 75% WCG, 20% sawdust and 5% binder gives a net calorific value of 18.72 MJ / kg higher than wood pellets despite the dilution of WCG with sawdust.

The calorific value of the biofuel is tested using standard techniques and generally a dry sample is used. The true calorific value is the calorific value of the sample that has not been dried.
Since the moisture content of the sample varies, the true calorific value cannot be compared between samples. In order to enable comparison, the true calorific value is normalized with a water content of 10%. This is calculated using the total CV and hydrogen content and is measured on the dried sample.

<Example>
<Example 1>
Durability Pellets containing 95% WCG and 5% glycerol were produced and tested for durability. In an initial test on a small scale pelletizer, pellets with 90% mechanical durability were produced using 5% glycerol and 95% WCG.

<Example 2>
Durability Tests were performed on pellets made from a raw material mixture containing WCG, sawdust and lignosulfonate, and pellets made from a raw material mixture containing WCG, sawdust and glycerol. The result is as follows.

<Table 1>

  The results show that the use of glycerol instead of lignosulfonate reduces the sulfur content from 0.31% to 0.12%. The initial deformation (ash melting temperature) of a mixture of 5% glycerol, 10% sawdust and 85% WCG was 1270 ° C. And it's lower than unmixed WCG, but above the minimum (temperature) of 1200 ° C required for biomass boilers.

<Example 3>
Test completed with "retail" coffee

<Table 2>

<Example 4>
Composition according to the invention using sawdust as filler in different coffee

<Table 3>

<Example 5>
Composition made according to the present invention using lignobond (lignosulfonate) as binder and sawdust as filler

<Table 4>

<Example 6>
Laboratory analysis of IWCG containing moisture versus RWCG containing moisture The moisture content and true calorific value are measured on the sample as received (no processing). All other measurements are made after the sample is dried.

<Table 5>

<Example 7>
Effect of Increasing Filler The experimental biofuel of the present invention was prepared. The biofuel contained IWCG, fillers (especially sawdust), and approximately 5% lignobond (lignosulfonate) as a binder. The durability of the biofuel was tested and the results are shown in the table below and in the graph of FIG. Durability could be further enhanced by adjusting the biofuel feedstock during preparation.

<Table 6>

<Example 8>
Durability distribution in the manufacturing process The durability distribution in the biofuel manufacturing process consists of approximately 5% lignobond and about 20% sawdust. Samples were taken and tested at 30 second intervals.
Also, the manufacturing process did not include adjustment of the raw material before compression. The durability can be further improved by adjusting the raw materials. The results are shown in the table below and in FIG.

<Table 7>

<Example 9>
Production of various compositions Examples of compositions produced according to the present invention are as follows.

Ｂ． 充填剤を備えるグリセロール結合剤

Ｃ． グリセロール結合剤

Ｄ． グリセロール結合剤＋充填剤

Ｅ． ｌｉｇｎｏｂｏｎｄ（リグノスルホネート）結合剤

Ｆ． ｌｉｇｎｏｂｏｎｄ（リグノスルホネート）結合剤＋充填剤

<Table 8>
A. Addition of filler

B. Glycerol binder with filler

C. Glycerol binder

D. Glycerol binder + filler

E. lignobond (lignosulfonate) binder

F. lignobond (lignosulfonate) binder + filler

<Example 10>
Additional compositions of the present invention were prepared and tested for durability. The experiment was conducted in a pilot scale mini-pelletizer and a full scale plant. The results are detailed in Tables 9-12 and FIGS.

Mini pelletizer A set weight of WCG was dispensed into the flexi container and manually mixed with the set amount of binder. This mixture was passed through a preheated pelletizer to further homogenize and apply heat. The remaining binder was added to the mixture and the raw material was passed through a pelleter. During discharge from the pelletizer, the sample collected in the middle of the flow.

Full scale pelletizer 400 kg of WCG was incorporated into the hopper and the appropriate amount of sawdust was added to obtain the desired composition. For example, 21 kg of sawdust was added to form a 95% WCG and 5% sawdust batch.
Then, WCG and sawdust were transported via a mixing auger screw to the live bin above the pellet head. The mixture was left in the live bottle for 10 minutes so that the ingredients were thoroughly mixed. The mixture was then passed through the preconditioner to a pellet press at a fixed feed rate. Lignonbond was added to the mixture at a fixed rate via a nozzle at the feed end of the preconditioner. Samples were taken at an intermediate stage of operation at the outlet of the cooler.

result
A. WCG / Filler Ratio Table 9 shows the change in pellet durability with the WCG / filler ratio. Surprisingly, it has been demonstrated that excellent pellet durability is obtained with a wide range of coffee / filler ratios.

<Table 9>

B. Retail WCG / Instant WCG Ratio The table below shows a mix of Urban WCG and Instant WCG. In these experiments, the total percentage (total) in the coffee mash mixture was set at 75%.

<Table 10>

C. Binder Criteria In these experiments, the amount of binder used in the pellet composition was examined. The results are tabulated below. These results suggest that the filler has a greater effect on the pellet durability than the binder.

<Table 11>

D. Alternative Filler Pellets were prepared using crushed bean hulls as an alternative filler instead of sawdust. The durability of the crushed bean hull pellets was 55.5%.
The crushed bean hull pellets did not achieve the durability goal of greater than 75%, but are considered reachable. The results are shown in Table 11.

<Table 12>

E. Alternative binders Pellets were prepared with various forms of glycerol binder. Durability was tested as before. The results are shown in Table 12.

<Table 13>

  The high durability value from Example 1 is probably due to the higher sawdust content than the effect of any particular glycerol binder. This is even more apparent since the lower the sawdust content, the less the durability. When the sawdust content reaches the “representative” value (c15-25%), the durability is somewhat reduced. However, values between 70% and 85% are still achievable.

Claims (47)

  A combustible biofuel composition comprising WCG.   The biofuel composition according to claim 1, wherein the composition is in the form of pellets or briquettes.   The biofuel composition according to claim 2, wherein the composition is a pellet for burning in a biomass boiler system.   The biofuel composition according to any one of claims 1 to 3, wherein the composition comprises at least 75% of the WCG.   The biofuel composition according to any one of claims 1 to 4, wherein the composition comprises a combustible fiber filler.   The filler is selected from sawdust, barley waste, hop waste, cocoa shell, sugar beet, straw, wood, nut shell, reed, bread waste, corn, wheat chaff, and barley chaff, The biofuel composition according to claim 5.   The biofuel composition according to claim 5 or 6, characterized in that the filler contained in the composition is less than 50%.   The biofuel composition according to any one of claims 1 to 7, further comprising a binder.   9. The biofuel composition according to claim 8, wherein the binder is selected from polysaccharides, glycerol, natural paraffin, vegetable oil, lignosulfonate, and molasses.   The biofuel composition according to claim 8 or 9, wherein the binder contained in the composition is 10% or less.   The raw material for manufacturing the biofuel composition as described in any one of Claims 1 thru | or 10.   The raw material according to claim 11, comprising at least 70% of the WCG. A method for producing a solid biofuel composition comprising the WCG, the method comprising:
a) providing the raw material composition according to claim 11 or 12,
b) compressing the raw material into pellets or briquettes.   The method of claim 13, wherein providing the raw material further comprises drying the WCG.   The method according to claim 14, wherein the WCG is dried to a moisture content of 6 to 20%.   16. The method according to any one of claims 13 to 15, wherein the step of providing the raw material comprises mixing at least one binder and filler with the WCG.   The method according to any one of claims 13 to 16, wherein the step of compressing the raw material into pellets comprises pressing the raw material by a pellet press.   The method of claim 17, further comprising cooling the pellet. An apparatus for preparing biofuel from WCG biomass, the apparatus comprising:
Means for drying WCG;
Means for mixing the WCG and one or more additives to produce a raw material;
Means for compressing the raw material. A biofuel composition or feed composition for producing biofuel, said composition comprising at least 50% WCG,
At least 50% of the WCG is IWCG.   The composition of claim 1, wherein the IWCG contained in the composition is at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85. %, At least 90%, at least 95%, at least 98%, or about 100%.   The composition according to claim 20 or 21, further comprising a binder.   The composition according to any one of claims 20 to 22, further comprising an oxidizing agent.   24. A composition according to any one of claims 20 to 23, further comprising a flammable filler.   25. The composition according to any one of claims 20 to 24, further comprising a processing agent.   The composition according to any one of claims 2 to 10, wherein the IWCG contained in the organism is at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%. At least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or about 100%. A biofuel composition according to any one of claims 20 to 26, comprising:
The assemblage is a solid biofuel, optionally in the form of pellets, briquettes, packs, or other compressed solid structures. A biofuel composition according to any one of claims 20 to 27, comprising:
The durability of the assemblage is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%. . A biofuel composition according to any one of claims 20 to 28, comprising:
The composition has a true calorific value of about 16 to 24 MJ / kg, about 17 to 23 MJ / kg, or about 18 to 22 MJ / kg. A method for producing a biofuel composition according to any one of claims 20 to 29, wherein the method comprises:
Providing the raw material composition according to any one of claims 20 to 25;
Compressing the raw material into solid biofuel.   31. The method of claim 30, further comprising the step of decontaminating the raw material to remove unwanted contaminants.   The method according to claim 30 or 31, further comprising a step of pre-drying the raw material.   33. A method according to any one of claims 30 to 32, further comprising the step of drying the material.   34. A method according to any one of claims 30 to 33, further comprising a set of extracting coffee oil from the raw material and optionally purifying the extracted oil.   The step of providing the raw material comprises the step of mixing any one or more of a binder, a filler, a processing agent, and an oxidizing agent with the WCG. The method according to claim 1.   36. The method according to any one of claims 30 to 35, further comprising the step of adjusting the raw material.   37. A method according to any one of claims 30 to 36, wherein the step of compressing the raw material comprises briquetting, packing or pelletizing the raw material.   Using the biofuel produced by the method of claims 30 to 37 or using biodiesel from the coffee oil extracted by the method of claim 34 to produce fuel for a dryer process. 38. A method according to any one of claims 30 to 37, further comprising the step of providing.   39. A method according to any one of claims 30 to 38, comprising the step of recovering heat generated during the performance of the method.   An apparatus for preparing biofuel from a raw material containing IWCG, comprising: means for drying the IWCG; and means for compressing the raw material.   41. The apparatus of claim 40, wherein the means for drying the IWCG is a dryer such as a rotary drum dryer, an industrial centrifuge, a microwave vibration dryer, or a mechanical press. To do.   The apparatus according to claim 40 or 41, further comprising means for performing preliminary drying for performing preliminary drying of the IWCG, such as a centrifuge, a dehydrating press, or a drying bed.   43. The apparatus according to any one of claims 40 to 42, further comprising adjusting means for adjusting the raw material. 44. Apparatus according to any one of claims 40 to 43, comprising:
The means for compressing the raw material is a die having a bore hole for pressing or extruding the raw material, a pellet head, a cold press, or a block press.   45. Apparatus according to any one of claims 40 to 44, further comprising heat recovery means for recovering heat from other parts of the apparatus.   46. Apparatus according to any one of claims 40 to 45, further comprising means for extracting coffee oil from the IWCG.   47. An instant coffee factory comprising the apparatus according to any one of claims 40 to 46.

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