HK1251861B - Biomass treatment process and apparatus - Google Patents

Description

Biomass processing method and biomass processing device

CROSS-REFERENCE TO RELATED APPLICATIONS

No related applications.

Technical Field

The present invention relates to a biomass processing method and a biomass processing device, including but not limited to a biomass densification molding and baking system.

Background Art

To reduce greenhouse gas (GHG) emissions, particularly those from coal-fired power plants and heavy industries (e.g., metallurgy), biomass can be co-combusted in coal-fired furnaces to generate sustainable energy. However, because most coal-fired power plants are based on pulverized coal furnaces, biomass cannot be co-combusted at high mixing percentages in coal-fired power plants without pretreatment (because biomass, by its very nature, still has a fibrous structure), making it difficult to grind and pulverize biomass. On the other hand, the energy value of biomass is much lower than that of coal, so pretreatment of biomass is mandatory to increase energy density and grindability in order to use the same equipment infrastructure of coal-fired power plants. In addition, the wide range of biomass types, from wood-based to herb-based to aquatic-based, inhibits large-scale standardization of biomass, making the establishment of a global market for biomass fuels difficult to achieve. To achieve the concept of multiple-input single-output (MISO), which has different biomass inputs but only one standardized biomass output, biomass compaction and pretreatment are necessary to achieve national and international standardization.

Torrefaction is an incomplete pyrolysis process (Figure 1) in which biomass is thermochemically pretreated in an oxygen-free or low-oxygen environment. The final product of torrefied biomass is hydrophobic, has a high energy density, is easily grinded, and more closely matches the properties of coal, making it easier to co-combust torrefied biomass in coal-fired power plants without requiring costly modifications or additions to existing equipment infrastructure.

On the other hand, the biomass through curing is not easy to use the resident lignin as adhesive and densely molded into the form of particles or briquette, because required high curing temperature can reduce the lignin concentration in the biomass through curing, and further increase the glass transition temperature of the resident lignin, so that conventional pellet press must operate at a higher temperature than current technology limits and with higher energy consumption. For the convenience of carrying out dense molding process to the biomass through curing, external binder is usually added. Unfortunately, external binder is not hydrophobic usually, so that when moisture content is high, the particles through curing or briquette with additional binder absorb water and disintegrate, resulting in transportation problems and storage problems, especially in rainy season or snowy season.

In the prior art, it is known that the raw materials need to be completely dry before the baking process can begin.

US Patent No. 9,347,011 teaches a torrefaction system having two independent torrefaction treatment units employing different treatment technologies, wherein the first treatment unit is primarily used to dry wet biomass that has not been densified, while the second treatment unit performs the torrefaction. The first treatment unit is of the type of fluidized bed reactor, which has limited raw material flexibility and is optimized to primarily process woody biomass such as sawdust. On the other hand, the raw material for the torrefaction system must be biomass that has not been densified, because densified biomass in the form of pellets or briquettes is not suitable for use in fluidized bed reactors. The subsequent densification of the pellets or briquettes after the torrefaction is energy-consuming and may require the use of an additional binder that is generally not hydrophobic.

U.S. Patent No. 9,206,368 teaches a single-stage mass flow torrefaction reactor. A disadvantage of this conventional reactor type is the "tunneling effect," particularly when scaled up to large reactors for larger production capacities. High-temperature gases from the bottom of the reactor chamber can find shortcuts through the biomass to the nearest gas exhaust outlet, creating distinct high- and low-temperature zones within the reactor chamber, leading to non-uniform quality of the torrefied biomass. Furthermore, the torrefaction parameter control of temperature, oxygen content, and residence time for a single stage is insufficient to flexibly process different types of biomass associated with varying properties and moisture content, making the MISO concept virtually impossible to implement. Furthermore, the feedstock for the torrefaction system is non-uniform and undensified biomass, "having a moisture content of 25% or less and a size ranging from about 13 mm to about -75 mm in its longest dimension," making densification into uniform pellets or briquettes after torrefaction energy-intensive and potentially requiring the use of an additional binder, which is typically not hydrophobic.

Therefore, there is an unmet need to improve the baking systems of the prior art using the present invention.

Summary of the Invention

The above needs are met by the various aspects and embodiments disclosed herein.

One of the objectives of the present invention is to densify the biomass into uniform pellets or briquettes before entering the torrefaction stage. This is intended to avoid the need for additional binders for densification if the densification stage of pellet and briquette formation is performed after the torrefaction stage. Furthermore, the densified biomass from different feedstocks has a common uniform size, which can be optimized for torrefaction in a two-stage compact moving bed reactor using controlled torrefaction parameters in each of the densification and torrefaction stages, thereby achieving the MISO concept.

Another object of the present invention is to provide a cost-effective torrefaction method and torrefaction apparatus for producing economical, hydrophobic torrefied pellets or briquettes without the use of binders, which is easily scalable to commercial batch production using a continuous torrefaction process based on reasonable cost equipment and feasibility applicable to the MISO concept, and does not require major modifications to existing equipment in coal-fired power plants.

Another object of the present invention is to avoid the "tunneling effect" and different residence times for each biomass particle or briquette in a compact moving bed torrefaction reactor that result in non-homogeneous torrefaction products. The present invention provides a high-temperature air distribution system in the form of a star, spider web, or ring that minimizes the "tunneling effect" so that the high-temperature air comes into uniform contact with all the biomass at the same set temperature within the torrefaction chamber. The scraper arm at the top of the torrefaction chamber evenly distributes the input biomass, and the biomass discharge device at the end of the treatment chamber evenly regulates the yield of torrefied biomass so as to maintain a constant residence time for each particle or briquette passing through the entire treatment chamber from top to bottom. The torrefaction chamber of the compact moving bed reactor of the present invention is further divided into a first treatment stage (pre-toasting stage) and a second treatment stage (toasting stage) so as to cope with a variety of different biomasses in relation to their properties and moisture content, thereby making it easier to implement the MISO concept with the present invention.

Therefore, a first aspect of the present invention relates to a method for processing biomass, comprising a densification stage, a first processing stage, a second processing stage, and a cooling processing stage. The densification stage comprises feeding substantially dried and size-reduced biomass to a continuous or batch biomass processing system, wherein the biomass contains a certain moisture content. In one embodiment, the moisture content contained in the biomass is in the range of 8% to 12% by weight. The densification stage also comprises densifying the biomass into pellets or briquettes. The densification stage further comprises discharging the densified biomass in the form of pellets or briquettes to the first processing stage. The first processing stage comprises heating the densified biomass containing the moisture content to a pre-toasting temperature for a first residence time. In one embodiment, the pre-toasting temperature used in the first processing stage is in the range of 260°C to 300°C. The biomass may be further dried or completely dried by evaporating the moisture from the biomass during the heating in the first processing stage, so that the biomass becomes at least partially torrefied or pre-toasted biomass after the heating. The pre-torrefied biomass is then discharged from the first processing stage to a second processing stage. The second processing stage involves heating the pre-torrefied biomass to a torrefaction temperature for a second residence time. In one embodiment, the torrefaction temperature used in the second processing stage is in the range of 240°C to 280°C. The second residence time may be equal to or longer than the first residence time. In one embodiment, the actual residence times used for the first and second residence times in the method of the present invention depend on the respective heights of the compartments performing the first and second processing stages, as well as the output rate of the torrefied biomass in the second processing stage after torrefaction. Following the heating in the second processing stage, the pre-torrefied biomass becomes torrefied biomass, and the torrefied biomass is then discharged from the second processing stage to the cooling processing stage. The cooling processing stage involves cooling the torrefied biomass to a temperature below 100°C. In one embodiment, the cooling in the cooling processing stage cools the torrefied biomass to approximately room temperature. In another embodiment, the cooling in the cooling processing stage is performed by directly contacting the torrefied biomass with a coolant gas. In other embodiments, the cooling in the cooling process stage is performed by directly contacting the torrefied biomass with water. In an exemplary embodiment, the first and second process stages of the present method are performed in the same torrefaction apparatus, unlike conventional methods in which they are performed in two separate apparatuses. A first high-temperature gas and a second high-temperature gas are respectively supplied to the first and second process stages to achieve the first and second process temperatures. In one embodiment, the first high-temperature gas is supplied to at least the first process stage via at least one first high-temperature gas inlet, and the remaining first high-temperature gas is discharged from at least the first process stage via at least one first high-temperature gas outlet. In another embodiment, the second high-temperature gas is supplied to at least the second process stage via at least one second high-temperature gas inlet, and the remaining second high-temperature gas is discharged from at least the second process stage via at least one second high-temperature gas outlet. The second high-temperature gas has a temperature at the second high-temperature gas inlet that is equal to or lower than the temperature of the first high-temperature gas at the first high-temperature gas inlet. The first and/or second high-temperature gases may include oxygen. In one embodiment, the first high-temperature gas is in direct contact with the densified biomass fed to the first process stage, wherein the first high-temperature gas contains 10% or less oxygen by volume. In another embodiment, the second high-temperature gas directly contacts the pre-torrefied biomass fed to the second process stage, wherein the second high-temperature gas comprises 3% or less oxygen by volume. The remaining portion of the first high-temperature gas containing volatile combustible gases and/or the remaining portion of the second high-temperature gas after the first process stage and/or the second process stage may be recycled. In one embodiment, the remaining portion of the first high-temperature gas exhausted through the first high-temperature gas outlet after the first process stage is recycled to a burner to generate flue gas, which is used to heat the first high-temperature gas, which is subsequently supplied to the first process stage through the first high-temperature gas inlet, via one or more heat exchange devices. In another embodiment, the remaining portion of the second high-temperature gas exhausted through the second high-temperature gas outlet after the second process stage is recycled to a burner to generate flue gas, which is used to heat the second high-temperature gas, which is subsequently supplied to the second process stage through the second high-temperature gas inlet, via one or more heat exchange devices. The burners used to heat the flue gases of the first and second high-temperature gases, respectively, via the one or more heat exchange devices, may be the same or different. Optionally, the flue gas leaving the heat exchange device can also provide heat to other stages, for example, before the densification stage. The flue gas heat from the heat exchange step can be used to reduce the moisture content of the biomass to a range of 8% to 12% by weight before being introduced into the densification step of pellet forming and briquette forming. By recycling the remaining portion of the first high-temperature gas and/or the second high-temperature gas to the burner via the one or more heat exchange devices, the method of the present invention can be self-sustaining after providing the initial first high-temperature gas and the second high-temperature gas to the first process stage and the second process stage.

The method of the first aspect of the present invention further includes a monitoring and control step via a control system to ensure that all key parameters meet predetermined torrefaction conditions, wherein the control system is configured to monitor and/or control one or more of the following parameters: the actual moisture content of the biomass at different stages of the method, the actual oxygen content of the high-temperature gas in the compartments used for the first and second processing stages, the actual temperature of the chamber, and/or the actual duration of the first and second residence times. The monitoring and control step of the method of the first aspect of the present invention can be performed by a system having sensors and a control device.

According to an embodiment of the first aspect of the present invention, the continuous or batch biomass processing system for performing the method is a compact moving bed reactor.

In a second aspect of the present invention, a continuous or batch biomass processing apparatus is provided that includes a processing chamber. In an exemplary embodiment, the processing chamber is of the compact moving bed reactor type. The processing chamber preferably comprises a double-walled housing and is preferably annular in form defining a substantially vertical axis. The processing chamber includes a first processing compartment and a second processing compartment. The processing chamber further comprises: at least one gas-tight valve inlet arranged at the top of the processing chamber, which is used to supply substantially dry and densely formed biomass into the processing chamber; a biomass distribution device; a biomass discharge device arranged at the bottom of the processing chamber, which is used to uniformly discharge the torrefied biomass in the form of particles; at least one gas-tight valve outlet as a final outlet for the torrefied biomass; at least one first high-temperature gas inlet and at least one first high-temperature gas outlet, which are respectively used to supply a first high-temperature gas to a first processing compartment of the processing chamber and to discharge a remaining portion of the first high-temperature gas from the first processing compartment of the processing chamber for recycling; at least one second high-temperature gas inlet and at least one second high-temperature gas outlet, which are respectively used to supply a second high-temperature gas to a second processing compartment of the processing chamber and to discharge a remaining portion of the second high-temperature gas from the second processing compartment of the processing chamber for recycling; an outer wall and an inner perforated wall of a double-walled shell, wherein an inner peripheral gap is defined between the outer wall and the inner perforated wall; a high-temperature gas distribution system, which comprises a plurality of perforated double separation plates arranged in a star shape, a spider web shape or a ring shape; and at least one perforated pipe arranged in the middle of the processing chamber. In one embodiment, the inner perforated wall, the hot gas distribution system comprised of perforated double separator plates, and the at least one perforated conduit rise along a vertical axis from the bottom to the top of the treatment chamber. In a preferred embodiment, a first hot gas inlet is mounted at the top of the first processing compartment of the treatment chamber. First hot gas is supplied through the first hot gas inlet and then pushed along the inner peripheral gaps of the double-walled shell and the gaps between the inner perforated double separator plates, which are arranged in a star, spiderweb, or ring pattern, to uniformly heat all biomass fed into the first processing compartment of the treatment chamber to a predetermined temperature for a first residence time. Thereafter, the remaining portion of the first hot gas after the first treatment stage is recovered through the perforated conduit in the middle of the treatment chamber and discharged through the at least one first hot gas outlet. Preferably, the at least one first hot gas outlet is mounted at the bottom of the first processing compartment to recover the remaining portion of the first hot gas so that heat from the remaining portion of the first hot gas can be recycled back to the first processing compartment via a heat exchange device. In a preferred embodiment, a second hot gas inlet is mounted at the bottom of the second processing compartment of the treatment chamber. A second high-temperature gas is provided through a second high-temperature gas inlet and then pushed along the inner peripheral gap of the double-walled shell and the gaps between the inner perforated double separation plates arranged in a star-shaped, spider-web-shaped, or ring-shaped manner, so as to uniformly heat all biomass fed into the second processing compartment of the processing chamber to a predetermined temperature for a second residence time. Thereafter, the remaining portion of the second high-temperature gas after the second processing stage is recovered through a perforated pipe in the middle of the second processing compartment and discharged through at least one second high-temperature gas outlet. Preferably, at least one second high-temperature gas outlet is installed at the top of the second processing compartment for recovering the remaining portion of the second high-temperature gas so that the heat from the remaining portion of the second high-temperature gas can be recycled back to the second processing compartment via a heat exchange device. In addition, the processing chamber can include a control system for monitoring and controlling different parameters according to predetermined conditions in each part/section/compartment of the processing chamber.

According to an embodiment of the second aspect of the invention, the biomass distribution device comprises at least one rotating scraper arm mounted in a motor driven rotating scraper wheel for evenly distributing the compacted biomass before discharge into the first processing compartment via the gas sealing valve inlet.

According to an embodiment of the second aspect of the present invention, the biomass discharge device includes two coaxial rotating disks driven by at least one rotary motor, wherein each of the coaxial rotating disks has a plurality of star-shaped openings and a plurality of blocks arranged alternately; the two coaxial rotating disks rotate in the same or opposite directions and at the same or different speeds so as to uniformly discharge the roasted biomass from the second processing compartment according to a controlled output rate.

According to an embodiment of the second aspect of the present invention, the gap between the double-walled shell and the gap between the perforated double separation plate of the first processing compartment and the gap between the double-walled shell and the gap between the perforated double separation plate of the second processing compartment are separated by non-perforated partitions to avoid any gas or temperature conflict between the first processing compartment and the second processing compartment or between the first processing stage and the second processing stage, while the pre-baked biomass moves from the first processing compartment to the second processing compartment without any blockage.

According to an embodiment of the second aspect of the present invention, the perforated double separation plate arranged in the form of a star or spider web comprises at least one first end connected to the perforated duct arranged in the middle of the process chamber.

According to another embodiment of the second aspect of the present invention, the perforated double separation plates arranged in the form of a star or spider web comprise at least one second end connected to the inner perforated wall of the process chamber.

According to an embodiment of the second aspect of the present invention, each of the perforated double separation plates divides the process chamber into at least two vertical sections.

According to an embodiment of the first or second aspect of the invention, after treatment in the first treatment stage or in the first treatment compartment, the pre-torrefied biomass is discharged by gravity into the second treatment stage or the second treatment compartment.

According to an embodiment of the second aspect of the present invention, the first high-temperature gas from the first high-temperature gas inlet includes oxygen in an amount equal to or less than 10% by volume.

According to an embodiment of the second aspect of the present invention, the second high-temperature gas from the second high-temperature gas inlet includes oxygen in an amount equal to or less than 3% by volume.

According to an embodiment of the second aspect of the invention, the predetermined temperature in the first processing compartment is in the range of 260°C to 300°C.

According to an embodiment of the second aspect of the invention, said predetermined temperature in the second processing compartment is in the range of 240°C to 280°C.

According to an embodiment of the second aspect of the present invention, the temperature of the second high-temperature gas is maintained equal to or lower than the temperature of the first high-temperature gas.

According to an embodiment of the second aspect of the invention, the height of the second processing compartment is equal to or higher than the height of the first processing compartment.

According to an embodiment of the first or second aspect of the invention, the duration of the first and second treatment stages or of the first and second residence times for treating the biomass in the first and second treatment compartments, respectively, depends on the height of the first and second treatment compartments and/or on the controlled output rate of the biomass discharge device.

According to an embodiment of the first aspect or the second aspect of the present invention, the control system includes sensors and control devices, which are used to monitor and control moisture content, oxygen content, temperature and residence time in real time to ensure that all parameters meet predetermined conditions in each stage or each compartment.

The present invention includes all steps and features mentioned or indicated in the specification individually or collectively, and any and all combinations or any two or more of these steps or features. The present invention also includes all these modifications and variations as described herein.

Other aspects and advantages of the present invention will become apparent to those skilled in the art from a reading of the ensuing description.

Various examples and features of the present invention and method will be partially described in the following detailed description. This summary of the invention is intended to provide an overview of the present invention and is not intended to provide an exclusive or exhaustive explanation. The following detailed description is included herein to provide more information about the present disclosure and method.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention will become apparent from the following description of the present invention when taken in conjunction with the accompanying drawings, in which:

FIG1 is a graph showing the general relationship between energy density, time, and temperature required at different stages of the pyrolysis process of woody biomass;

2A is a flow chart showing a densification molding stage and a baking stage in a method according to an embodiment of the present invention;

2B is another flow chart showing the densification and baking stages of a method with additional control and monitoring steps according to another embodiment of the present invention;

3 is a schematic diagram showing the structure of a device and the flow of different materials according to an embodiment of the present invention, wherein the flow directions of different materials are indicated by arrows;

4 is a top view of the biomass distribution device in the device according to an embodiment of the present invention as viewed from the inlet of the gas sealing valve;

5A is a perspective view of a biomass discharge device in a device according to an embodiment of the present invention;

5B is a schematic diagram showing the structure of two coaxial disks of a biomass discharge device in an apparatus according to an embodiment of the present invention, wherein the shaded portion represents a block, and the unshaded portion represents an opening of each disk;

FIG6A is a cross-sectional view of a perforated double separation plate (section AA' or section BB' in FIG3), showing a star-shaped high-temperature gas distribution system used in the apparatus or method of the present invention;

6B is a perspective view of a perforated double separation plate showing a star-shaped high-temperature gas distribution system used in the apparatus or method of the present invention;

FIG7A is a cross-sectional view of a perforated double separation plate (section AA' or section BB' in FIG3), showing a spider-web-shaped high-temperature gas distribution system used in the apparatus or method of the present invention;

FIG7B is a cross-sectional view of a perforated double separation plate (section AA' or section BB' in FIG3), showing another spider-web-shaped high-temperature gas distribution system used in the apparatus or method of the present invention;

FIG8 is a cross-sectional view of a perforated double separation plate (section AA' or section BB' in FIG3), showing an annular high-temperature gas distribution system used in the apparatus or method of the present invention;

FIG. 9 is a schematic diagram illustrating a perforated structure of an inner perforated double separation plate according to an embodiment of the present invention.

DETAILED DESCRIPTION

definition

As used herein, the terms "a" or "an" are used to include one or more than one, and the term "or" is used to represent a non-exclusive "or", unless otherwise specified. In addition, it should be understood that phrases or terms used herein and not otherwise defined are used for descriptive purposes only and are not limiting. In addition, all publications, patents, and patent documents cited herein are incorporated herein by reference in their entirety, just as if individually incorporated by reference. In the event of any inconsistency between the usage herein and those documents incorporated by reference, the usage in the incorporated document should be considered supplementary to that herein; for inconsistencies, the usage in this document shall prevail.

The term "about" can allow a degree of variability in a value or range, for example, within 10% or within 5% of the stated value or limit of the stated range.

The term "independently selected" refers to reference to the same group, different groups, or a combination thereof, unless the context clearly indicates otherwise. Thus, under this definition, for example, the phrase "X1, X2, and X3 are independently selected from inert gases" should include the following: X1, X2, and X3 are all the same, X1, X2, and X3 are different, X1 and X2 are the same but X3 is different, and other similar permutations and combinations.

References in the specification to "one embodiment," "an embodiment," "an exemplary embodiment," etc., indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, whether or not explicitly described, it is assumed that such feature, structure, or characteristic can be implemented in conjunction with other embodiments within the knowledge of those skilled in the art.

Numerical values expressed in range format should be interpreted in a flexible manner to include not only the numerical values explicitly stated as the limits of the range, but also all individual numerical values or subranges contained within that range, as if each numerical value and subrange were explicitly stated. For example, a concentration range of "about 0.1% to about 5%" should be interpreted to include not only the explicitly stated concentrations of about 0.1% to about 5% by weight, but also individual concentrations (e.g., 1%, 2%, 3%, and 4%) and subranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, and 3.3% to 4.4%) within the indicated range.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprising" or "consisting of" should be understood to express the inclusion of the stated individual or group of individuals but not the exclusion of any other individual or group of individuals. It should also be noted that in this disclosure, particularly in the claims and/or paragraphs, terms such as "comprise," "comprising," or "consisting of" may have the meanings ascribed to them by U.S. patent law; for example, they may mean "including," "comprised of," etc.; and terms such as "consisting essentially of" and "consisting essentially of" have the meanings ascribed to them by U.S. patent law, for example, they allow for elements not expressly recited but exclude elements found in the prior art or that affect the basic or novel characteristics of the invention.

Furthermore, throughout this specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprising" or "consisting of," will be understood to express the inclusion of a stated individual or group of individuals but not the exclusion of any other individual or group of individuals.

In the biomass processing methods described herein, the steps can be performed in any order without departing from the principles of the invention, except where a temporal or operational sequence is expressly stated. Statements in the claims that a first step is performed first and a number of other steps are performed subsequently should be deemed to mean that the first step is performed before any other steps, but that the other steps may be performed in any suitable order unless further stated in the other steps regarding the order. For example, a claim element stating "step A, step B, step C, step D, and step E" should be interpreted as step A being performed first and step E being performed last, and steps B, C, and D may be performed in any order between steps A and E and still fall within the semantic scope of the claimed method. Given steps or subsets of steps may also be repeated.

Furthermore, specified steps may be performed simultaneously unless the claim language explicitly states that the steps are to be performed independently. For example, a claim step of performing X and a claim step of performing Y may be performed simultaneously within a single operation, and the resulting method would fall within the semantic scope of the claimed method.

The term "biomass" should be understood to mean any organic material, preferably any plant or plant-based organic material, including but not limited to woody biomass (e.g., sawdust, forest residues, etc.); herbaceous biomass (e.g., corn stover and residues, bagasse, sugarcane residues, etc.); fruit biomass; aquatic biomass; blends and mixtures.

Other definitions of selected terms used herein can be found in the detailed description of the invention and apply throughout. Unless otherwise defined, all other technical terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs.

Detailed description of the invention

In the following description, preferred embodiments are described. It will be apparent to those skilled in the art that modifications, including additions and/or substitutions, may be made without departing from the scope and spirit of the invention. Specific details may be omitted so as not to obscure the invention; however, this disclosure is written to enable those skilled in the art to practice the teachings herein without undue experimentation.

The following examples are provided as exemplary embodiments of the present invention, but should not be construed as limiting the present invention to the specific embodiments described. Unless otherwise indicated, all parts and percentages are by weight. All numerical values are approximate. When a numerical range is given, it should be understood that embodiments outside of the range may still fall within the scope of the present invention. The specific details described in each example should not be interpreted as essential features of the present invention.

Example

FIG2A shows a method for processing biomass using a continuous or batch biomass processing system, the method comprising a densification stage (500), a first processing stage (800), a second processing stage (900), and a cooling processing stage (600). In FIG2B , in addition to the stages shown in FIG2A , an additional control system (300) having sensors and control devices is added to the method for real-time monitoring and control of actual moisture content, actual oxygen content, actual temperature, gas flow rate and residence time, etc., to ensure that all parameters meet predetermined densification and baking conditions, and the method comprises: feeding substantially dried and size-reduced biomass (10) containing a certain moisture content (preferably between 8% and 12% by weight) into the densification stage (500) to generate densified biomass in the form of pellets or briquettes. the densified biomass being discharged from the densification stage (500) to a first processing stage (800), the first processing stage comprising heating the moisture-containing densified biomass to a pre-toasting temperature (preferably in the range of 260° C. to 300° C.) for a first residence time, wherein the moisture-containing densified biomass is substantially completely dried by evaporating the moisture in the first processing stage (800), and the densified biomass is at least partially toasted after the first processing stage (800) to form pre-toasted biomass. Thereafter, the pre-torrefied biomass is discharged from the first treatment stage (800) to a second treatment stage (900), the second treatment stage comprising heating the pre-torrefied biomass supplied to the second treatment stage (900) at a temperature preferably in the range of 240°C to 280°C for a second residence time to form torrefied biomass (20); the torrefied biomass (20) is discharged from the second treatment stage (900) to a cooling treatment stage (600) via a biomass discharge device (70) and a gas sealing valve outlet (25). A heat exchange step (700) is also provided using flue gas (12) from the burner by a heat exchange device for heating a portion of the high-temperature gas recovered after the first and second treatment stages, so as to reintroduce the recovered high-temperature gas into the first and second treatment stages. The flue gas (12) leaving the heat exchange device can also provide heat to other stages (701), for example before the densification molding stage (500), and the flue gas heat from the heat exchange step (700) can be used to reduce the moisture content of the biomass to a range of 8% to 12% by weight before the biomass is introduced into the densification molding step of pellet molding or briquette molding.

Preferably, the first treatment stage (800) and the second treatment stage (900) of the present method are performed in the same treatment chamber. Compared to any conventional method, performing the first treatment stage and the second treatment stage in the same treatment chamber according to the present method can reduce the energy required for the baking of the biomass while using the same amount of time and temperature. According to the present method, the same amount of energy as the conventional method can be used while reducing the amount of time and temperature used for the baking of the biomass. In short, compared with the conventional method, the present method can at least save energy, time and temperature used for the baking of the biomass, thereby reducing costs.

During the first processing stage (800) and the second processing stage (900) of the present method, the corresponding continuous or batch biomass processing system or biomass processing device includes at least one first high-temperature gas inlet (110) and at least one first high-temperature gas outlet (111); and at least one second high-temperature gas inlet (220) and at least one second high-temperature gas outlet (222), as shown in Figure 3, for the corresponding first high-temperature gas and second high-temperature gas to flow into and out of the corresponding processing compartments of the device.

In Figure 3, a first high-temperature gas (11) from a first high-temperature gas inlet (110) in a first processing compartment performing a first processing stage is in direct contact with the substantially dried and densified biomass from the densification stage via a gas sealing valve inlet (15), wherein the first high-temperature gas comprises oxygen in an amount equal to or less than 10% by volume. A second high-temperature gas (22) from a second high-temperature gas inlet (220) in a second processing compartment performing a second processing stage is in direct contact with the pre-torrefied biomass from the first processing stage, wherein the second high-temperature gas comprises oxygen in an amount equal to or less than 3% by volume.

At least a portion (11a) of the first high-temperature gas (11) containing volatile combustible gas exiting the first high-temperature gas outlet (111) of the first processing compartment is recycled to the burner (400) for generating flue gas (12), which is used to heat a portion of the recovered first high-temperature gas (11) to be reintroduced into the first processing compartment via a heat exchange device. Similarly, at least a portion (22a) of the second high-temperature gas (22) containing volatile combustible gas exiting the second high-temperature gas outlet (222) of the second processing compartment is recycled to the burner (400) for generating flue gas (12), which is used to heat a portion of the recovered second high-temperature gas (22) to be reintroduced into the second processing compartment via a heat exchange device.

Since the first treatment stage is used to completely dry out any remaining moisture in the densified biomass (10), the first residence time of the biomass in the first treatment stage is equal to or shorter than the second residence time used in the second treatment stage for performing the actual torrefaction.

In order to quickly dry and remove the remaining moisture in the relatively low-temperature densified biomass (10) in the first process stage, the temperature of the first high-temperature gas (11) at the first high-temperature gas inlet (110) in the first process stage is set to be equal to or higher than the temperature of the second high-temperature gas (22) at the second high-temperature gas inlet (220) in the first process stage. The temperature of the first high-temperature gas at the first high-temperature gas inlet and the temperature of the second high-temperature gas at the second high-temperature gas inlet can be monitored and controlled by the control and monitoring device (300 in Figure 2B), respectively.

The torrefied biomass leaving the second treatment stage is then cooled in a cooling treatment stage (600) to a temperature below 100°C, preferably to a temperature of about room temperature (e.g., 25°C), because the torrefied hot pellets or briquettes are reactive. The cooling treatment stage is performed by directly contacting the torrefied biomass with a coolant gas or by directly contacting the torrefied biomass with water.

Figure 3 provides a device of the continuous or batch compact moving bed reactor type for treating biomass according to the method of the present invention. The device comprises a treatment chamber having a double-walled shell and preferably in the form of an annular shape, which defines a substantially vertical axis. An inner peripheral gap is defined between the outer wall and the inner wall of the double-walled shell. The treatment chamber comprises: a supply of biomass (10) from the top of the treatment chamber via at least one gas-tight valve inlet (15); at least one biomass distribution device (40); a biomass discharge device (70) for uniformly discharging the torrefied biomass particles at the bottom of the treatment chamber; at least one final outlet for torrefied biomass via at least one gas-tight valve outlet (25); at least one first high-temperature gas inlet (110) and at least one first high-temperature gas outlet (111) for the first treatment stage; at least one second high-temperature gas inlet (220) and at least one second high-temperature gas outlet (222) for the second treatment stage; an inner perforated wall (60) of the double-walled shell of the treatment chamber; a high-temperature gas distribution system comprising a plurality of gas-tight valves arranged in the treatment chamber in the form of a star, spider web or an annular shape. A perforated double separation plate (62), at least one perforated pipe (91, 92) arranged in the middle of the treatment chamber, wherein the inner perforated wall (60), the perforated double separation plate (62) and the perforated pipe (91, 92) rise from the bottom to the top of the treatment chamber along the vertical axis, and wherein the first high-temperature gas (11) is supplied to at least one first high-temperature gas inlet (110) preferably installed at the top of the first treatment compartment, and is pushed along the inner peripheral gap of the double-walled shell and the gap of the perforated double separation plate (62) arranged in a star-shaped, spider-web-shaped or ring-shaped form to uniformly heat all the densely formed biomass (10) in the first treatment compartment, and is finally recovered through the perforated pipe (91) arranged in the middle of the treatment chamber and discharged by at least one first high-temperature gas outlet (111) preferably installed at the bottom of the first treatment compartment. Similarly, the second high-temperature gas (22) is supplied to at least one second high-temperature gas inlet (220) preferably installed at the bottom of the second processing compartment, pushed along the inner peripheral gap of the double-walled shell and the gap of the perforated double separation plate (62) arranged in a star shape, spider web shape or ring shape to uniformly heat all the pre-baked biomass in the second processing compartment, and is finally recovered through the perforated pipe (92) arranged in the middle of the processing chamber, and discharged by at least one second high-temperature gas outlet (222) preferably installed at the top of the second processing compartment.

Depending on the scale of production, multiple double-wall structures, preferably in an annular shape, can be further introduced into the processing chamber. In the case of larger production scales, an additional double-wall structure in the shape of an annulus can be introduced inside the double-walled shell of the processing chamber, comprising an outer wall and an inner wall (either one or both walls can be perforated), defining an inner gap for an additional hot gas inlet to guide the hot gas along the inner gap of the additional double-wall structure in the annular shape, and then through the outer and inner perforated walls of the double-wall structure to either the first processing compartment or the second processing compartment. In other words, the device can be easily expanded by adding a double-wall structure to the processing chamber. One advantage of introducing the double-wall structure is that when the production scale increases, even if the volume of the biomass being processed increases, the hot gas can be effectively and evenly distributed in the processing chamber. The cost of expansion by introducing the additional double-wall structure inside the processing chamber of the present invention is relatively lower than the cost of modifying any conventional torrefaction reactor to cope with the increase in production scale, because conventional torrefaction reactors are generally limited by their shape and design during modification. Another advantage of this device over conventional torrefaction reactors in the expanded case is that, even with the introduction of multiple double-wall structures to direct more high-temperature gas into the processing chamber, only at least one perforated pipe needs to be arranged in the middle of the processing chamber along its vertical axis to direct the remaining portion of the high-temperature gas out of the processing chamber. This significantly reduces modification costs based on the design of this device. Furthermore, in terms of efficiency, the introduction of this type of double-wall structure in the expanded case allows for more uniform distribution of the high-temperature gas within the processing chamber, meaning that this device is more energy-efficient, less time-consuming, and can maintain consistent product quality when processing biomass.

Figure 4 shows an embodiment of a biomass distribution device having at least one rotating scraper arm (42) mounted on a rotating scraper wheel (40) driven by a motor (30) to evenly distribute biomass from a gas sealing valve inlet (15).

In order to separate the first high temperature gas (11) and the second high temperature gas (22) between the double-walled shell of the first process compartment and the double-walled shell of the second process compartment, a non-perforated gas separator (65) is provided.

For structural stability, the perforated double separation plates (62) are arranged in a star or spider web form, and at least one first end of the perforated double separation plates is connected to a perforated pipe (91, 92) in the middle of the treatment chamber.

For structural stability, the perforated double separation plates (62) are arranged in a star or spider web form, and at least one second end of the perforated double separation plates is connected to the inner perforated wall (60) of the processing chamber.

Figures 6A, 6B, 7A, 7B, and 8 illustrate a high-temperature gas distribution process chamber in a star-shaped, spider-web-shaped, or annular shape, respectively, wherein a perforated double separator plate (62) is arranged to divide the process chamber into at least two substantially vertical sections. As shown in Figures 6A and 6B, the star-shaped perforated double separator plate (62) divides the process chamber (including the first process compartment and the second process compartment) into eight vertical sections, which are arranged around perforated pipes (91, 92) arranged in the middle of the process chamber along a vertical axis. As shown in Figure 7A, the spider-web-shaped perforated double separator plate (62) divides the process chamber into sixteen vertical sections; while in Figure 7B, another spider-web-shaped perforated separator plate (62) divides the process chamber into eight vertical sections. In Figure 8, the perforated double separator plate (62) divides the process chamber into two vertical sections, one of which is surrounded by the other.

Biomass (10) moves from the first processing stage to the second processing stage by means of gravity in order to cancel any mechanical or pneumatic components therebetween, thereby saving maintenance, energy, time and cost. When the pre-baked biomass moves from the first processing compartment to the second processing compartment in the processing chamber of this device, it passes through the vertical space of the perforated double separation plate. In order to avoid any perforation of the perforated double separation plate (62) being blocked by biomass during passing, the perforation is designed to only allow high-temperature gas (11, 22) to flow through while biomass (10) cannot flow through. An embodiment of a perforated double separation plate with this type of perforation is shown in Figure 9. The solid arrows represent the flow of high-temperature gas, and the unshaded arrows represent the direction in which biomass moves from the first processing compartment to the second processing compartment inside the processing chamber. In the embodiment shown in Figure 9, the perforations (93) are configured to only allow gas to flow into or out of the gap of the perforated double separation plate, without allowing biomass or other solids to pass through the perforations. In order to have such a configuration, a cap-like structure is formed by opening a portion of the wall of the perforated double separator plate so that the perforations are substantially permeable to gas but not to biomass or other solids, which is similar to a slightly curved protrusion (93a) extending from the wall of the perforated double separator plate. Moreover, in this embodiment, the slightly curved protrusion formed by opening the wall of the perforated double separator plate can protrude in one direction so that the pore-like opening (93b) that can only pass through gas faces the direction in which the biomass movement from the first processing compartment to the second processing compartment is not blocked by the protrusion (93a), further reducing the probability of biomass passing through the perforations (93a) of the perforated double separator plate. The perforations are preferably made by stamping and punching the metal material sheet forming the wall of the perforated double separator plate. This type of perforation can also be applied to other parts of the present invention that need perforations to allow high-temperature gas to flow into and/or out of the processing chamber, such as perforated pipes or inner perforated walls.

For the first treatment stage of pre-baking for rapid drying and removal of residual moisture in the biomass (10), even in direct contact with the first high-temperature gas (11) at a temperature of 260-300°C, the first high-temperature gas (11) can tolerate an oxygen concentration of up to 10% by volume without self-initiating internal combustion of the biomass. Conversely, when the completely dried biomass enters the second treatment stage, in order to avoid spontaneous combustion of the biomass due to direct contact with the second high-temperature gas (22) at a temperature of 240-280°C, the oxygen concentration needs to be maintained at up to 3% by volume. The temperature of the second treatment stage is set to be equal to or lower than the temperature of the first treatment stage in order to better control the mass and energy balance of the baked biomass and to avoid the occurrence of carbonization.

In order to achieve energy saving in a torrefaction method that saves external fuel in an autothermal mode, at least a portion of the first high-temperature gas (11) containing volatile combustible gas leaving the first process stage is recycled to the burner (400) for generating flue gas (12), which is used to heat the first high-temperature gas (11) to be reintroduced into the first process compartment where the first process stage is performed, via a heat exchange device, and at least a portion of the second high-temperature gas (22) containing volatile combustible gas leaving the second process stage is recycled to the burner (400) for generating flue gas (12), which is used to heat the second high-temperature gas (22) to be reintroduced into the second process compartment where the second process stage is performed, via a heat exchange device. The one or more heat exchange devices for heating the flue gas of the first high-temperature gas and the second high-temperature gas, respectively, may be the same or different. In this way, no additional external fuel is required to continuously heat the first high-temperature gas and the second high-temperature gas for the first process stage and the second process stage or the first process compartment and the second process compartment, thereby providing a self-sustaining method or device for processing biomass.

Since the biomass (10) is transferred from the gas-tight valve inlet (15) to the gas-tight valve outlet (25) from top to bottom by gravity, the residence time of the biomass in the treatment chamber is proportional to the height of the corresponding treatment compartment of the treatment chamber. The first treatment stage, which is mainly used to completely dry and remove moisture from the compacted biomass, can be performed within a residence time that is equal to or shorter than the residence time of the torrefaction treatment in the second treatment stage. Therefore, the height of the first treatment compartment in which the first treatment stage is performed is equal to or shorter than the height of the second treatment compartment in which the second treatment stage is performed.

In order to provide a uniform residence time for each particle or briquette passing through the first and second processing stages, a specially designed biomass discharge device (70) should be used. Figures 5A and 5B show an embodiment of the biomass discharge device, which includes two coaxial rotating disks (71 and 72) driven by at least one rotary motor (80), wherein each disk has a plurality of openings (711 or 722) and a plurality of briquettes (710 or 720) arranged alternately in a star shape, and wherein the two disks rotate in the same or opposite directions and/or at the same or different speeds so as to uniformly discharge all the torrefied biomass from the second processing chamber according to a controlled output rate.

In order to effectively control and monitor the entire compacting and baking system, a control system (300) having sensors and control devices is installed to monitor and control the actual moisture content, actual oxygen content and actual temperature in the processing chamber, thereby ensuring that all parameters meet the predetermined baking conditions.

Although the present invention has been described with reference to a limited number of embodiments, the specific features of one embodiment should not necessarily be attributed to other embodiments of the invention. The method in some embodiments may include many steps not mentioned herein. The method in other embodiments does not include or is substantially free of any steps not enumerated herein. There are many modifications and variations derived from the described embodiments. The appended claims are intended to cover all such modifications and variations that fall within the scope of the invention.

Industrial Applicability

The method of the present invention is effective and energy efficient in processing biomass and other equivalent solid wastes (particularly woody/agricultural biomass/solid wastes) by first performing a densification stage in the form of homogenized pellets or briquettes prior to the roasting stage in accordance with the MISO principle, thereby eliminating most of the problems associated with post-densification of roasted biomass (including but not limited to the use of binders). In addition, the apparatus of the present invention is not only useful for implementing the method of the present invention, but is also applicable to other processing methods such as those requiring uniform distribution of input material, requiring real-time control and monitoring of the processing chamber with a continuous supply of recirculating high-temperature gas, and/or requiring uniform discharge of the final product. The apparatus of the present invention is also suitable for processing materials such as coffee beans or other agricultural/non-agricultural materials that require real-time control of oxygen, temperature, residence time and homogeneity for thermal and thermochemical processing methods.

Claims (42)

1. A biomass treatment device, comprising: A processing chamber with a double-walled shell; At least one gas-tight valve inlet is disposed at the top of the processing chamber, the at least one gas-tight valve inlet being used to feed biomass into the processing chamber; At least one gas-tight valve outlet is disposed at the bottom of the processing chamber, the at least one gas-tight valve outlet being used to discharge the final product from the processing chamber; A biomass dispensing device for uniformly dispensing biomass from the inlet of the gas-sealed valve; A biomass discharge device for uniformly discharging roasted biomass after roasting before discharging it through the outlet of the gas-tight valve; The processing chamber includes: The first processing compartment and the second processing compartment are used for pre-baking and baking of biomass, respectively. At least one first high-temperature gas inlet and at least one first high-temperature gas outlet are respectively arranged at the top and bottom of the first processing compartment, and the at least one first high-temperature gas inlet and at least one first high-temperature gas outlet are respectively used to supply the first high-temperature gas to the first processing compartment and to discharge the first high-temperature gas from the first processing compartment; At least one second high-temperature gas inlet and at least one second high-temperature gas outlet are respectively arranged at the bottom and top of the second processing compartment. The at least one second high-temperature gas inlet and the at least one second high-temperature gas outlet are respectively used to supply second high-temperature gas to the second processing compartment and to discharge second high-temperature gas from the second processing compartment. The processing chamber includes an outer wall and an inner perforated wall forming the double-walled shell, an inner peripheral gap defined between the outer wall and the inner perforated wall, multiple perforated double separation plates forming a high-temperature gas distribution system, and perforated pipes arranged in the middle of the processing chamber. The inner perforated wall, each of the plurality of perforated double-separation plates, and the perforated conduit rise continuously from the bottom to the top of the processing chamber along the vertical axis of the processing chamber, and each of the plurality of perforated double-separation plates is arranged radially outside the perforated conduit, with one end connected to the perforated conduit and the other end connected to the inner perforated wall, such that each of the plurality of perforated double-separation plates cannot move relative to the perforated conduit and the inner perforated wall. Each of the at least one first high-temperature gas inlet and the at least one second high-temperature gas inlet leads to the inner peripheral gap and the gap of the plurality of perforated double separation plates, such that the first high-temperature gas and the second high-temperature gas supplied from the at least one first high-temperature gas inlet and the at least one second high-temperature gas inlet respectively pass through the inner peripheral gap and the gap of the plurality of perforated double separation plates, and flow laterally and radially through the perforations toward the biomass that is moving from top to bottom by gravity. 2. The biomass processing apparatus according to claim 1, wherein the first high-temperature gas is supplied to the first processing compartment via the first high-temperature gas inlet and subsequently pushed along the inner peripheral gap of the double-walled shell and the gap of the plurality of perforated double separation plates to uniformly heat the biomass fed into the processing chamber via the gas-sealed valve inlet to a pre-baking temperature. 3. The biomass processing apparatus according to claim 1, wherein the second high-temperature gas is supplied to the second processing compartment via the second high-temperature gas inlet and is subsequently pushed along the inner peripheral gap of the double-walled shell and the gap of the plurality of perforated double separation plates to uniformly heat the biomass from the first processing compartment to the baking temperature. 4. The biomass processing apparatus according to claim 1, wherein the biomass dispensing device comprises at least one rotary scraper arm, the rotary scraper arm being mounted in a motor-driven rotary scraper wheel to uniformly dispense biomass from the gas-sealed valve inlet. 5. The biomass processing apparatus according to claim 1, wherein the gap between the perforated double separation plate and the double-walled shell of the first processing compartment and the second processing compartment is separated by a non-perforated partition. 6. The biomass treatment apparatus according to claim 1, wherein the perforated double separation plate includes at least one first end, the at least one first end being connected to the perforated pipe disposed in the middle of the treatment chamber. 7. The biomass processing apparatus according to claim 1, wherein the perforated double separation plate further includes at least one second end connected to the inner perforated wall. 8. The biomass processing apparatus according to claim 1, wherein the perforated double separation plate is arranged in the processing chamber to divide the processing chamber into at least two vertical sections. 9. The biomass treatment apparatus according to claim 1 further includes a control device for real-time control and monitoring of various conditions to ensure that the conditions are maintained at a predetermined level, the conditions including temperature, humidity, flow rate, oxygen content, and residence time in different parts of the biomass treatment apparatus. 10. The biomass processing apparatus according to claim 1, wherein the predetermined temperature used in the first processing compartment is in the range of 260°C to 300°C. 11. The biomass processing apparatus according to claim 1, wherein the predetermined temperature used in the second processing compartment is in the range of 240°C to 280°C. 12. The biomass processing apparatus according to claim 1, wherein the baking temperature of the second processing compartment is equal to or lower than the pre-baking temperature of the first processing compartment. 13. The biomass processing apparatus according to claim 1, wherein the height of the second processing compartment is equal to or higher than the height of the first processing compartment. 14. The biomass processing apparatus according to claim 1, wherein the duration of the biomass residing in the first processing compartment is equal to or shorter than the duration of its residing in the second processing compartment. 15. The biomass processing apparatus of claim 14, wherein the duration for which the biomass resides in the first and second processing compartments depends on the relative height of the first and second processing compartments and/or the output rate of the biomass controlled by the outlet of the gas-sealed valve. 16. The biomass processing apparatus of claim 1, further comprising a burner and one or more heat exchange devices for recirculating a portion of the first and second high-temperature gases containing volatile combustible gases from the biomass after the first and second high-temperature gases are discharged from the first and second processing compartments respectively via the first high-temperature gas outlet and the second high-temperature gas outlet, and using the remaining portion of the first and second high-temperature gases containing volatile combustible gases to generate flue gas in the burner, the flue gas being used to heat a portion of the first and second high-temperature gases to be supplied to the first and second processing compartments respectively via the one or more heat exchange devices. 17. The biomass processing apparatus according to claim 1, wherein the first processing compartment is maintained at an oxygen level in the first high-temperature gas at a volume percentage equal to or less than 10%. 18. The biomass processing apparatus according to claim 1, wherein the second processing compartment is maintained at an oxygen level in the second high-temperature gas with a volume percentage equal to or less than 3%. 19. The biomass processing device according to claim 1, wherein the perforated double separation plate is arranged in a star-shaped, spider web-shaped, or ring-shaped form. 20. The biomass processing apparatus according to claim 1, wherein, after the pre-baking in the first processing compartment, the biomass is moved by gravity to the second processing compartment for baking. 21. The biomass processing apparatus of claim 1, wherein the inner perforated wall, the plurality of perforated double separation plates and/or the perforated pipe includes perforations, the perforations being configured to allow gas to pass through but not the biomass or other solids, such that the first high-temperature gas and the second high-temperature gas are effectively supplied to the first processing compartment and the second processing compartment and are uniformly distributed in the first processing compartment and the second processing compartment. 22. The biomass processing apparatus of claim 21, wherein each of the perforations includes a protrusion extending from the wall of the inner perforation wall, the plurality of perforated double separation plates, and/or the perforated conduit through a portion of the open wall, such that the protrusion defines an opening facing the direction in which the biomass is blocked by the protrusion. 23. The biomass processing apparatus of claim 22, wherein the step of opening a portion of the wall of the inner perforated wall, the wall of the plurality of perforated double separation plates, and/or the wall of the perforated pipe to form a plurality of perforations including the protrusions is performed by stamping and punching a sheet of metal material. 24. A method for treating biomass using the biomass treatment device according to claim 1, the method comprising the following stages: Densification stage; First processing stage; The second processing stage; and Cooling process stage The densification stage includes feeding basically dried and reduced-size biomass containing a certain moisture content into the biomass processing device in a continuous or batch manner, densifying the biomass to form it into pellets or briquettes, and discharging the densified biomass in pellet or briquette form into the first processing stage. The first processing stage includes heating the densified biomass containing the moisture content to a pre-baking temperature and maintaining it for a first residence time, so that the densified biomass is completely dried by evaporating the moisture through the heating in the first processing stage, thereby forming pre-baked biomass, and discharging the pre-baked biomass into the second processing stage. The second processing stage includes heating the pre-baked biomass to a baking temperature and maintaining it for a second residence time to form baked biomass, and discharging the baked biomass into the cooling processing stage. The cooling process includes cooling the roasted biomass to a cooling temperature; The moisture content in substantially dried and/or reduced-size biomass is in the range of 8% to 12% by weight of the total biomass weight; The first high-temperature gas and the second high-temperature gas are respectively supplied to the first processing stage and the second processing stage to achieve the pre-baking temperature and the baking temperature, respectively. 25. The method of claim 24, wherein, after providing the first high-temperature gas or the second high-temperature gas to the first processing stage or the second processing stage, at least a portion of the first high-temperature gas or the second high-temperature gas containing volatile combustible gases from the pre-baked biomass or baked biomass is recovered from the first processing stage or the second processing stage for recycling to a burner for generating flue gas, the flue gas being used to heat the first high-temperature gas or the second high-temperature gas to be provided to the first processing stage or the second processing stage via one or more heat exchange devices. 26. The method of claim 25, wherein the first high-temperature gas is provided to the first processing stage via at least one first high-temperature gas inlet, and a remainder of the first high-temperature gas after being provided to the first processing stage is subsequently discharged from the first processing stage via at least one first high-temperature gas outlet for recirculation back to the first processing stage via the one or more heat exchange devices. 27. The method of claim 25, wherein the second high-temperature gas is provided to the second processing stage via at least one second high-temperature gas inlet, and a remainder of the second high-temperature gas after being provided to the second processing stage is subsequently discharged from the second processing stage via at least one second high-temperature gas outlet for recirculation back to the first processing stage via the one or more heat exchange devices. 28. The method of claim 24, wherein the temperature of the second high-temperature gas supplied to the second processing stage is equal to or lower than the temperature of the first high-temperature gas supplied to the first processing stage. 29. The method of claim 24, wherein the first high-temperature gas and the second high-temperature gas comprise oxygen in different volume percentages. 30. The method of claim 29, wherein the first high-temperature gas comprises an oxygen content of 10% or less by volume. 31. The method of claim 29, wherein the second high-temperature gas comprises an oxygen content of 3% or less by volume. 32. The method of claim 24, wherein the baking temperature is equal to or lower than the pre-baking temperature. 33. The method of claim 24, wherein the pre-baking temperature is in the range of 260°C to 300°C. 34. The method of claim 24, wherein the baking temperature is in the range of 240°C to 280°C. 35. The method of claim 24, wherein the second dwell time is equal to or greater than the first dwell time. 36. The method of claim 24, wherein the cooling temperature is below 100°C. 37. The method of claim 24, wherein the cooling temperature is approximately room temperature. 38. The method of claim 24, wherein the cooling is performed by bringing the roasted biomass into direct contact with a coolant gas or water. 39. The method of claim 24, further comprising a real-time control and monitoring step for controlling and monitoring conditions used in the densification stage, the first processing stage, the second processing stage, and the cooling stage, wherein the conditions include temperature, residence time, oxygen content, moisture content, and/or gas flow rate. 40. The method of claim 24, wherein the first and second processing stages are performed in the same processing chamber, and the processing chamber is a continuous or batch moving bed reactor type. 41. The method of claim 24, wherein the first high-temperature gas and the second high-temperature gas are uniformly distributed throughout the processing chamber by a high-temperature gas distribution system. 42. The method of claim 24, wherein, prior to the heating of the densified biomass in the first processing stage, the densified biomass is uniformly distributed by means of a biomass dispensing device.