WO2018116657A1

WO2018116657A1 - Palm trunk processing method and palm trunk processing apparatus

Info

Publication number: WO2018116657A1
Application number: PCT/JP2017/039730
Authority: WO
Inventors: 良之幸; 修若村; 猛西
Original assignee: 新日鉄住金エンジニアリング株式会社
Priority date: 2016-12-22
Filing date: 2017-11-02
Publication date: 2018-06-28
Also published as: JP6180614B1; JP2018103074A; MY182113A

Abstract

A palm trunk processing method comprises: a grinding step for defibrating and grinding palm trunks into soft structure and vascular bundles using a grinder; a hydration step for hydrating the palm trunks, which have been ground in the grinding step, with water in an amount equal to or less than the upper limit for the amount of moisture that the palm trunks can absorb; and a compression step for compressing the pulverized palm trunks, which have been hydrated in the hydration step.

Description

Palm trunk processing method and palm trunk processing apparatus

The present invention relates to a palm trunk processing method and a palm trunk processing apparatus for generating liquid fuel, solid fuel, fertilizer, and the like from an oil palm trunk (hereinafter referred to as palm trunk).
This application claims priority based on Japanese Patent Application No. 2016-249473 filed in Japan on December 22, 2016, the contents of which are incorporated herein by reference.

In Indonesia and Malaysia, oil palm is actively cultivated, but oil palm is cut and replanted every 20-25 years to maintain oil productivity. The harvested palm trunks contain a lot of moisture and thus have little value as timber. Most of them were incinerated for burning in plantations. However, in recent years, field burning has been prohibited from the viewpoint of environmental protection, and therefore, a technique for obtaining liquid fuel or solid fuel from a palm trunk, for example, without incineration of the palm trunk has attracted attention.
On the other hand, solid fuel obtained from palm trunk contains alkali metal such as potassium (hereinafter simply referred to as “potassium”). When this solid fuel is burned in a boiler or the like, it is derived from potassium or the like. Ashes were generated and adhered to the boiler, so-called slugging or the like sometimes occurred.
Therefore, for example, Patent Document 1 below discloses a technique for removing alkali components such as potassium by squeezing the palm trunk until the water content is 35% or less after crushing the palm trunk.
Further, for example, Patent Document 2 below discloses a technique for more effectively removing alkali components such as potassium by squeezing a palm trunk once, then adding water and squeezing again.

Japanese Unexamined Patent Publication No. 2015-73953 Japanese Unexamined Patent Publication No. 2012-153790 Japanese Laid-Open Patent Publication No. 2004-352962 Japanese Unexamined Patent Publication No. 2016-1225030

Palm trunk is a biomass raw material, and the composition of alkali components such as potassium in the raw material varies greatly depending on the logging location, etc., so design with a high alkali composition value with a margin in the composition of the raw material palm trunk I had to do it. However, in order to reduce the high concentration potassium contained in the squeezed residue to the desired content by the method of Patent Document 1, a high squeezing pressure is required, leading to an increase in the power of the squeezing machine.
Patent Document 2 is proposed as a similar herbic alkali removal method. However, this method needs to destroy the cell wall to facilitate the elution of potassium by hydration, so it is necessary to squeeze before hydration, which means squeezing twice, A lot of power was needed.
In addition, as disclosed in

Patent Documents

3 and 4, a method of eluting potassium by leaching the palm trunk into water before squeezing is also presented, but even when the potassium concentration in the palm trunk is not so high, After the water is absorbed up to the maximum moisture content of the palm trunk, the potassium concentration in the eluate is made equal to or less than the potassium concentration in the palm trunk so that the potassium is eluted. Inevitably, a large amount of waste liquid was generated. For this reason, not only an elution tank and a heating device for elution of potassium are required, but also a water supply facility and a waste liquid treatment device are necessary, which makes the entire facility large.

The present invention has been made in consideration of such circumstances, and even when the potassium concentration in the palm trunk fluctuates and becomes high, the potassium concentration is not more than that of wood pellets allowed as a solid fuel. An object of the present invention is to provide a processing apparatus and a processing method for a palm trunk that can be performed and that does not require a large amount of water supply or waste liquid and that is simple and suppresses an increase in power.

As a result of diligent research, the present inventors have found that most of the potassium in the palm trunk is present in the moisture in the palm trunk, and the moisture content of the raw palm trunk is approximately 60 to 75 [%]. It was found that the water content can be increased up to 85 [%] by adding water. And, as a pretreatment, the present inventors add water to the range where the palm trunk is saturated to reduce the potassium concentration in the liquid in the palm trunk, and then perform the squeezing so that the potassium concentration in the juice residue It came to come up with the process of reducing.

In order to solve the above-mentioned problem, the processing method according to the first aspect of the palm trunk of the present invention includes a pulverizing step in which the palm trunk is defibrated and pulverized into a soft tissue and a vascular bundle using a pulverizer, A hydration step of adding water to the palm trunk pulverized in the pulverization step within a range equal to or lower than the upper limit of the amount of water that can be absorbed, and a pressing step of squeezing the powdered palm trunk hydrated in the hydration step. It is characterized by that.

According to the first aspect, the palm trunk log is defibrillated into a vascular bundle and a soft tissue having a small particle diameter by a pulverizer, and then water is added within a range in which the palm trunk can absorb water. The potassium concentration in the squeezed residue can be kept low by squeezing after making the potassium concentration in the liquid low.
Since the water added to the palm trunk is the addition of water within the range that the palm trunk can absorb water, not only the amount of water can be minimized, but also no waste liquid is generated. Furthermore, since this hydration can be made into a soft tissue having a fine particle size, the water absorption and the water absorption speed are improved, and the hydration process can be accomplished in a short time.
In addition, the present method of squeezing after hydration is the moisture content of the palm trunk where the squeezing power in squeezing is squeezed even when squeezing to the same squeezed residue moisture content as in the process of squeezing without hydration Therefore, the increase in the water content of the palm trunk supplied to the squeeze machine due to hydration does not increase the power of the squeeze machine.

In the method for treating a palm trunk according to the second aspect of the present invention, when the palm trunk pulverized in the pulverization step is sieved after drying, the weight-based integrated sieving has a particle size of 0.3 [mm]. It is 5.4 [%] or less.

In this case, when pulverizing the palm trunk, it is easy to absorb moisture, and the fine soft tissue can be in a state that has not been broken. It can be surely successful.

In the method for treating a palm trunk according to the third aspect of the present invention, the pulverized palm trunk is sprinkled or sprayed to add water in the hydration step.

In this case, for example, water can be added to the palm trunk during conveyance by a belt conveyor or the like, so that the efficiency of the hydration process can be reliably achieved.

The method for treating a palm trunk according to the fourth aspect of the present invention detects the presence or amount of moisture that has not been absorbed by the palm trunk in the hydration step, and determines the amount of hydration to the palm trunk based on the detection result. Control.

In this case, it is possible to prevent the palm trunk from being excessively hydrated and to ensure the efficiency of the hydration process.

In the palm trunk treatment method according to the fifth aspect of the present invention, the amount of water added to the palm trunk in the hydration step is 1.7 times or less with respect to the mass of the palm trunk.

In this case, by setting the amount of water added to the palm trunk below the upper limit of the amount of water that can be absorbed by the palm trunk, it is prevented from excessively adding water to the palm trunk, and the efficiency of the hydration process is reliably achieved. be able to.

The processing method of the palm trunk which concerns on the 6th aspect of this invention is the content rate of the potassium which the squeeze residue obtained by the said pressing process contains the amount of hydration to the palm trunk in the said hydration process, or this squeeze residue Control based on the alkali concentration.

In this case, since the amount of hydration is controlled based on the content of potassium contained in the squeezed residue, water is added to the palm trunk without excess and deficiency, and the efficiency of the hydration process can be reliably achieved.

A palm trunk processing apparatus according to a seventh aspect of the present invention is a palm trunk processing apparatus for performing the palm trunk processing method, wherein the palm trunk is fibrillated into soft tissue and vascular bundles. A pulverizer for pulverization, a hydrator for adding water to the palm trunk pulverized by the pulverizer, and a squeezer for pressing the palm trunk hydrated by the hydrator are provided.

According to the palm trunk processing apparatus of the seventh aspect, moisture in a range in which the palm trunk can absorb water after pulverizing the palm trunk log into a vascular bundle and a soft tissue having a small particle size by a pulverizer. Is added to make the potassium concentration in the palm trunk low, and then the potassium concentration in the squeezed residue can be kept low by pressing.
The water added to the palm trunk is the addition of water within the range that the palm trunk can absorb water, so that the amount of water added can be minimized and no extra waste liquid is generated. Furthermore, since this hydration can be made into a soft tissue having a fine particle size, the water absorption and the water absorption speed are improved, and the hydration process can be accomplished in a short time.
In addition, the present method of squeezing after hydration is the moisture content of the palm trunk where the squeezing power in squeezing is squeezed even when squeezing to the same squeezed residue moisture content as in the process of squeezing without hydration Therefore, the increase in the water content of the palm trunk supplied to the squeeze machine due to hydration does not increase the power of the squeeze machine.

According to the method for treating a palm trunk according to the first aspect, water is added within a range where water can be absorbed as the palm trunk, so that not only the amount of water can be suppressed but also excess waste liquid is not generated. Furthermore, since the potassium concentration in the liquid in the palm trunk can be reduced by absorbing water into the palm trunk and then squeezed, the potassium concentration in the juice residue can be kept low. Compared with the case where potassium is reduced to a predetermined concentration, an increase in the power of the juicer can be prevented.
Since the alkali concentration of potassium or the like in the palm trunk, which is a biomass raw material, varies greatly, for example, even when the alkali concentration of potassium or the like in the palm trunk raw material is as high as 1.5 [% -dry] By squeezing after adding water to the trunk, it is possible to provide a simple palm trunk treatment method that can keep the potassium concentration of the squeezed residue low while preventing increase in power of the squeezer.
According to the method for treating a palm trunk according to the second aspect, when the palm trunk is pulverized, it is easy to absorb moisture and does not break the fine soft tissue, and is defibrated into the soft tissue and the vascular bundle. Therefore, the water absorption and water absorption speed of the pulverized palm trunk can be improved, and the efficiency of the hydration process can be reliably achieved.
According to the palm trunk processing method according to the third aspect, for example, water can be added to the palm trunk during conveyance by a belt conveyor or the like, so that the efficiency of the hydration process can be reliably achieved.
According to the method for treating a palm trunk according to the fourth aspect, it is possible to prevent the palm trunk from being excessively hydrated and to ensure the efficiency of the hydration process.
According to the method for treating a palm trunk according to the fifth aspect, the amount of water added to the palm trunk is less than the upper limit of the amount of water that can be absorbed by the palm trunk, thereby excessively adding water to the palm trunk. It can prevent and make it possible to make the hydration process more efficient.
According to the method for treating a palm trunk according to the sixth aspect, since the amount of water is controlled based on the content of potassium or the like contained in the squeezed residue, the palm trunk can be watered without excess or deficiency. Thus, for example, when the alkali concentration such as potassium in the palm trunk is lowered, the pre-treatment can reduce the potassium concentration more than necessary, and the predetermined squeezed residue potassium concentration can be obtained.
According to the treatment apparatus for a palm trunk according to the seventh aspect, since water is added within a range in which potassium can absorb water, no extra waste liquid is generated, and further, water in the palm trunk is absorbed by water absorption into the palm trunk. Since it squeezes after making a potassium concentration into a low state, the potassium concentration in a squeezed residue can be restrained low. Moreover, compared with the case where it squeezes without adding water to a palm trunk and reduces potassium to a predetermined | prescribed density | concentration, the abrasion of a squeeze machine and the increase in power can be prevented.

2 is an explanatory diagram showing an overview of a processing apparatus 10. FIG. 3 is an explanatory diagram illustrating a configuration example of a processing device 10. FIG. It is a figure which shows an example of the squeeze machine. It is a schematic diagram explaining the relationship of each parameter. It is a table | surface which shows the correlation of each parameter. It is a graph which shows the relationship between K density | concentration in an eluate, and K density | concentration in the liquid component in a palm trunk fragment. It is a schematic diagram explaining the specific example in the case of pressing without making a palm trunk absorb water. It is a figure which shows the numerical value of each parameter corresponding to FIG. 6A. It is a schematic diagram explaining the specific example in the case of making it squeeze after making a palm trunk absorb water. It is a figure which shows the numerical value of each parameter corresponding to FIG. 7A. Squeezed residue渣含water rate φ _r = 0.35 [-] in the case of the ratio _D r / _{D f} for residue K concentration _{D r} raw material K concentration _{D f} of, and after the water absorption water content phi _{f ',} the It is a graph which shows a relationship. It is a figure explaining the feature at the time of turndown of a hydration process. It is a graph of a time-dependent change of the moisture content at the time of making a crushed piece residue immersed. It is a graph which shows the ratio of the soft tissue and vascular bundle contained in a palm trunk for every particle size. It is a graph which shows the total sieving for every particle diameter of the whole palm trunk crushing piece. It is a graph which shows the total sieving for every particle size of a soft tissue and a vascular bundle. It is a graph which shows the total sieving for every particle diameter of the whole palm trunk fragment and soft tissue. It is a graph which shows the total sieving for every particle size of a soft tissue and a vascular bundle. It is a figure explaining the control method of the amount of water Q per unit time.

First, the palm trunk processing apparatus 10 which implements the palm trunk processing method according to the present embodiment will be described.
As shown in FIG. 1, the processing apparatus 10 includes a pulverizer 1, a water mixer 3, a detector 5, a controller 4, a juicer 2, an analyzer 6, a liquid fuel generator 7, And a solid fuel generation unit 8.

The pulverizer 1 pulverizes the palm trunk into a powder form of 0.1 to 6.0 [mm] on the basis of the particle size by sieving classification after drying. The water machine 3 hydrates the palm trunk (hereinafter referred to as palm trunk crushed pieces) pulverized into a powder form by watering or spraying to cause the palm trunk crushed pieces to absorb moisture. In the following description, adding water to the palm trunk crushed piece is referred to as “hydrolysis”, and the palm trunk crushed piece absorbing water is referred to as “water absorption”.
The detection part 5 detects the water | moisture content which was not absorbed in the water | moisture content watered by the palm trunk fragment. The control unit 4 controls the amount of water that the water machine 3 adds to the palm trunk fragment.
The squeezer 2 squeezes the water-sunk palm trunk fragment and separates it into a squeezed juice and a squeezed residue. The analyzer 6 detects the content rate of potassium contained in the squeezed residue or the alkali concentration of the squeezed residue. The liquid fuel production | generation part 7 produces | generates liquid fuels, such as ethanol, from squeezed liquid. The solid fuel production | generation part 8 produces | generates solid fuels, such as a fuel pellet, from squeezed residue. In addition, since nutrients, such as potassium, are contained in juice, you may produce | generate a fertilizer etc. from juice.

Next, the liquid fuel generator 7 will be described. The liquid fuel production | generation part 7 has the squeezed liquid tank 7a, the fermenter 7b, the distiller 7c, and the product tank 7d.
The squeezed liquid tank 7a stores the squeezed liquid, and adds and mixes nitric acid. By adding and mixing nitric acid to the juice, the pH is adjusted and the efficiency of fermentation is increased. The temperature of the squeezed liquid in the squeezed liquid tank 7a is managed to be, for example, 50 [° C.] or more, and thereby, germs contained in the squeezed liquid are killed and the fermentation efficiency is further increased.

The fermenter 7b adds a predetermined microorganism to the squeezed liquid whose pH has been adjusted, and ferments the squeezed liquid. The juice is fermented to produce ethanol. The distiller 7c purifies ethanol by distilling the fermented liquor containing ethanol produced in the fermenter. The product tank 7d stores ethanol purified by the distiller 7c.

Next, the solid fuel generator 8 will be described. The solid fuel generator 8 includes a dryer 8a, a crusher 8b, a molding machine 8c, and a cooler 8d.
The dryer 8a blows dry air, for example, and dries the juice residue. The moisture contained in the squeezed residue is reduced to, for example, 10 [%] or less on the mass basis by the dryer 8a. The crusher 8b crushes the dried juice residue into a predetermined size. The molding machine 8c molds the crushed juice residue into a predetermined shape to obtain fuel pellets. The fuel pellets are transferred to the cooler 8d and cooled until the temperature reaches a predetermined temperature or lower.

Next, a specific configuration example of the processing apparatus 10 will be described with reference to FIG. The pulverizer 1 pulverizes the palm trunk into powder using a hammer mill or the like. The crushed palm trunk crushed pieces are conveyed from the pulverizer 1 to the belt conveyor 9 by a shovel car or the like. Above the belt conveyor 9, for example, a water heater 3 such as a spray nozzle is disposed. While the palm trunk crushed pieces are being conveyed by the belt conveyor 9, the water sprinkled or sprayed from the water machine 3 is absorbed by the palm trunk crushed pieces. The belt conveyor 9 is disposed to be inclined upward with respect to the transport direction. For this reason, the water | moisture content which was not absorbed by the palm trunk crushed piece flows out below among the water | moisture content hydrated from the water machine 3 to the palm trunk crushed piece. A detection unit 5 is disposed below the belt conveyor 9. The detection unit 5 detects the outflow amount of outflow moisture that has flowed out without being absorbed by the palm trunk fragment (hereinafter simply referred to as outflow amount). The detection unit 5 is electrically connected to the control unit 4 and outputs the outflow amount detection result to the control unit 4.

The palm trunk crushed pieces that have been hydrated by the water machine 3 are put into the squeezer 2 disposed at the end of the belt conveyor 9 in the traveling direction. The squeezer 2 squeezes the crushed palm trunk fragment to separate it into a solid component and a liquid component. Here, the separated liquid is the juice and the separated solid is the juice residue.
FIG. 3 is a configuration diagram illustrating an example of the juicer 2. The squeezer 2 is an inscribed roll type squeezer. The squeezer 2 includes a ring roll 21, an inscribed roll 22, an input port 23, a discharge port 24, a cylinder 25, and a pressing roll 26.

The ring roll 21 is supported so as to be vertically movable and rotatable. The inscribed roll 22 is supported so as not to move up and down and to rotate. The ring roll 21 and the inscribed roll 22 are rotated in the same direction by a driving means (not shown). The cylinder 25 presses the pressing roll 26 upward. This pressing force can be adjusted. The pressing roll 26 transmits the pressing force received from the cylinder 25 to the ring roll 21. With the above configuration, the pressure when the palm trunk fragment is sandwiched between the ring roll 21 and the inscribed roll 22 can be adjusted by adjusting the pressing force of the cylinder 25.
The palm trunk crushed pieces are introduced from the introduction port 23 and are squeezed between the ring roll 21 and the inscribed roll 22 to be separated into a squeezed juice and a squeezed residue. The separated squeezed liquid is discharged from a discharge port (not shown) to the outside and is put into the liquid fuel generating unit 7. The separated squeezed residue is discharged from the discharge port 24 and is input to the solid fuel generator 8.

As shown in FIG. 2, a part of the separated juice residue is put into the analyzer 6. The analyzer 6 is an atomic absorption spectrometer, for example, and can analyze the mass of potassium contained in the juice residue per unit mass. If the squeezed residue contains a lot of potassium, the fuel pellets generated by the solid fuel generator 8 will also contain a lot of potassium, and the ash derived from potassium when the fuel pellets are burned in a boiler or the like. Many occur. If this ash adheres to the inside of the boiler, it may lead to so-called slugging. For this reason, it is necessary to make the mass of potassium contained in the squeezed residue below a predetermined amount.

The analyzer 6 may analyze the concentration of alkali metals other than potassium. Most of the alkali component contained in the palm trunk is potassium, but the prediction accuracy of ash adhesion as a solid fuel can be improved by considering the analytical value of alkali metals other than potassium. An atomic absorption spectrometer can be used as the analyzer 6.
Analyzer 6 is electrically connected to the control unit 4, the mass of potassium contained in the squeezed residue per unit mass (hereinafter, simply referred to as the residue K concentration D _r) and outputs to the control unit 4. When the analyzer analyzes the alkali concentration of the juice residue, the control unit 4 outputs the alkali concentration of the juice residue to the control unit 4.
The control unit 4 includes a processing unit such as a CPU (not shown) and a storage unit such as a RAM (not shown).

Then, the amount of moisture Palm trunk crushed pieces to the water absorption, the residue K concentration D _r, the relationship will be described.

As shown in FIG. 4A and FIG. 4B, the palm trunk crushed piece raw material, the crushed piece raw material after water absorption, and the crushed piece squeezed residue are indicated using subscripts f, f ′, and r. The subscript i is used for representative representation. F _i [kg] is the total mass of the palm trunk crushed raw material, the crushed raw material after water absorption, and the crushed squeezed juice residue, the solid mass of the components contained therein is S _i [kg], the liquid content Let L _i [kg] be the mass of. Similarly, the mass of potassium contained in the Palm trunk fragments w _{i [kg]} (hereinafter, simply referred to as a raw material K mass w _i) to.
At this time, the moisture content φ _i (hereinafter referred to as the moisture content φ _i ) in the palm trunk crushed piece raw material, the crushed piece raw material after water absorption, and the crushed piece squeezed residue is expressed by the following formula (1).
φ _i = L _i / (S _i + L _i ) (1)
Further, the K concentration D _i in the raw material which is the mass of potassium per solid content S _i [kg] in the palm trunk crushed piece raw material, the crushed piece raw material after water absorption, and the crushed piece squeezed residue (hereinafter simply referred to as K concentration D _i) Is expressed by the following formula (2).
D _i = w _i / S _i (2)

Further, K concentration C _i in the raw material which is the mass of potassium in the liquid content L _i [kg] in the palm trunk crushed piece raw material, the crushed piece raw material after water absorption, and the crushed piece squeezed residue (hereinafter simply referred to as K concentration in liquid) C _i ) is expressed by the following mathematical formula (3).
C _i = w _i / L _i (3)

FIG. 5 shows the relationship between the K concentration in the liquid in the palm trunk fragment and the K concentration on the eluate side when the palm trunk fragment is immersed in water while changing the water amount ratio. Since the slope of the K concentration on the elution side of the horizontal axis and the K concentration in the liquid content in the palm trunk fragment on the vertical axis is 1, K in the palm trunk is dissolved in the liquid in the palm trunk. You can see that
The palm trunk crushed pieces absorbed by the juicer 2 are squeezed to reduce the mass of water contained in the palm trunk crushed pieces from L _f [kg] to L _r [kg]. At this time, the concentration of potassium present in the water of the squeezed residue and the concentration of potassium eluted in the squeezed liquid are equal to the potassium concentration C in the palm trunk liquid. liquid concentration C _r in squeezed residue and liquid concentration C _f or C _{f 'in} strip material is represented by the following formula (4a) or (4b).
C _{f ′} = C _r (when water is added) (4a)
C _f = C _r (when not added) (4b)
Therefore, the mass w _r [kg] of potassium in the liquid content L _r [kg] contained in the squeezed residue (hereinafter simply referred to as the squeezed residue K mass w _r ) is expressed by the formulas (3) and (4a) or From (4b), it is represented by the following formula (5a) or (5b).
w _r = C _{f ′} × L _r (at the time of water addition) (5a)
w _r = C _f × L _r (when not hydrolyzed) (5b)

Further, the residue K concentration D _r is the mass of potassium per squeezed residual solid fraction S _{r [g]} is expressed by the following equation (2) below.
D _r = w _r / S _r (2a)
The potassium contained in the squeezed residue is considered to be present in the water in the squeezed residue, but when the fuel pellets are produced, the water is evaporated by the dryer 8a and the potassium is the solid content of the squeezed residue. To remain. Therefore, this residue K concentration D _r is indirectly represents the amount of potassium contained in the fuel pellets.

When the palm trunk crushed piece is squeezed, a part of the solid content of the palm trunk crushed piece is mixed with the juice and flows out. _If the ratio of the solid content Sf of the raw material remaining in the juice residue and recovered is η (hereinafter, simply referred to as solid content recovery rate η), the mass S _r [kg of the solid content contained in the juice residue (hereinafter, simply referred to as squeezed residual solid fraction S _r) is expressed by the following equation (6).
S _r = η × S _f (6)

Moreover, and _{_D} r / _D _f _'ratio Dr / D _f in the residue K concentration _{D r} against and raw material K concentration _{D _f'} fragments in the raw material after water absorption K concentration D _f is equation (1), (2) Is expressed by the following mathematical formula (7a) or (7b).
D _r / D _{f ′} = {(1-φ _{f ′} ) φ _r } / {φ _{f ′} (1-φ _r )} At the time of addition (7a)
D _r / D _f = {(1-φ _f ) φ _r } / {φ _f (1-φ _r )} When not hydrolyzed (7b)
The above formula (7a) and (7a) can be the same is squeezed residue渣含water ratio phi _r, if it is possible to increase the after water moisture content phi _{f ',} the residue K for the raw material K concentration D _f It shows that the ratio D _r / D _f of the concentration D _r can be reduced. That is, even if the squeeze residue water content is not lowered by increasing the squeeze pressure, if the water content can be increased to a proper water content after water absorption, the effect of removing K in the raw material and residue can be obtained. ing.

Next, the mass hydrolysis unit 3 Palm trunk fragments to water by hydrolysis, L _a [kg] (hereinafter, simply referred to as the water absorption L _a) when that is included in the Palm trunk fragments after water absorption The moisture mass L _{f ′} (hereinafter, simply referred to as the moisture amount L _{f ′} after water absorption) is represented by the following mathematical formula (8).
L _{f ′} = L _f + L _a (8)

Here, from the formula (1), as shown in the following formula (9), a water absorption amount L _a / F _f (hereinafter simply referred to as a unit water absorption amount L _a / F _f ) per unit mass of the raw material is obtained. It is done.
_{_{L a / F f = (φ}} f '-φ f) / (1-φ f') ... (9)

The relationship of the above relational expressions (1) to (9) is shown in FIG. 4B.

The above relationship will be described by applying a specific example.
As shown in FIGS. 6A and 6B, the palm trunk fragment having a total mass F _f = 448 [kg] includes a solid content S _f = 148 [kg] and a liquid content L _f = 300 [kg]. In the liquid component L _f , it is assumed that potassium of the raw material K mass w _f = 1 [kg] is present. At this time, the raw material moisture content φ _f is φ _f = 0.67 [−] according to Equation (1). Further, potassium in the liquid concentration _{C f} is the equation (3) from _{C f = 0.00333 [kg-K} / kg-Liquid], versus solids in the raw material K concentration _{D f} is _{D f} from Equation (2) = 0.00677 [kg-K / kg-solid].
When the squeezing machine 2 squeezes this palm trunk crushed piece, assuming that the solid content recovery rate η = 0.75 [−], the squeezed residue solid content S _r is _expressed by the squeezed residue solid content from Equation (6). S _r = 111 [kg]. And since the mass of the water | moisture content contained in the squeeze residue when squeezing the squeeze residue moisture content at φ _r = 0.35 [−] is L _r = 60 [kg], it is included in the palm trunk fragment. which was _w f = 1 of potassium [kg], squeezed residue K mass _{w r} that remains squeezed residue becomes from equation _{(5b), w r = 0.2} [kg]. At this time, the K concentration D _{r in the} residue is D _r = 0.0018 [kg-K / kg-solid].

On the other hand, the case where it squeezes by adding water to a palm trunk fragment will be described with reference to FIGS. 7A and 7B.
As shown in FIG. 7A and FIG. 7B, it is the same as the case of adding water with the total mass F _f = 448 [kg], the solid content S _f = 148 [kg], and the liquid content L _f = 300 [kg]. It is assumed that the amount L of the raw material K is not doubled, that is, potassium of the raw material K mass w _f = 2 [kg] is present in the portion L _f .
At this time, the raw material moisture content φ _f is φ _f = 0.67 [−] according to Equation (1). Further, the potassium concentration in the liquid is C _f = 0.00667 [kg-K / kg-Liquid] from Equation (3), and the K concentration D _f in the solid content raw material is D _f = 0. 0135 [kg-K / kg-solid].

It is assumed that water of La = 291 [kg] is absorbed by the palm trunk crushed pieces by the water machine 3 hydrating the palm trunk crushed pieces. At this time, the water content L _f after water absorption is L _{f ′} = 591 [kg] according to Equation (8). In addition, the potassium concentration in the liquid is 1.97 times thinner than before addition. Further, the post-water-absorption content φ _{f ′} is φ _{f ′} = 0.8 [−] from the mathematical formula (1).

When the juicer 2 squeezes the water-absorbed palm trunk fragment, if the solid content recovery rate η = 0.75 [−], the squeezed residue solid content S _r is _{expressed as} S _r = 111 [kg]. And when the squeezed residue moisture content is squeezed at φ _r = 0.35 [−], the mass of moisture contained in the squeezed residue is L _r = 60 [kg], so it is included in the palm trunk fragment. of potassium _w f = 2 [kg] that were, squeezed residue K mass _{w r} that remains squeezed residue, from equations _(5a), the w r = 0.20 [kg].
The residue K concentration _{D r} becomes from Equation _{(2), D r = 0.0018} [kg-K / kg-solid].

When comparing the results shown in FIG. 6A, FIG. 6B, FIG. 7A, and FIG. 7B, when water is added, even if the potassium concentration Dr. residue K concentration D _r of is reduced to the same 0.0018 as when squeezed without hydro [kg-K / kg-solid ]. Residue K concentration D _r, when generating the solid fuel from the squeezed residue and represents the mass of potassium contained in the solid fuel. Therefore, by the residue K concentration D _r and predetermined numerical value or below by the squeezing from the hydro Palm trunk fragments, it is possible to reduce the amount of potassium contained in the solid fuel to the identified wood pellets Thus, it is possible to prevent phenomena such as slugging that occur when this solid fuel is burned.

Next, the relationship between the raw material in K concentration D _f and the residue K concentration D _r, will be explained with reference to FIG.
The graph shown in FIG. 8 shows the ratio D _r / D _f of the K concentration D _r in the residue to the K concentration D _{f in} the raw material on the vertical axis and the horizontal axis after water absorption, with the moisture content φ _f of the raw material fragment as a parameter. The water content is φ _{f ′} . As shown in the mathematical expressions (7a) and (7b), D _r / D _f is a function of the raw material moisture content φ _{f ′} and the squeeze residue moisture content φ _r , and the graph shown in FIG. _{Since f} fluctuates in the range of 0.6 to 0.75 depending on the palm trunk growth condition, cutting position, storage method, etc., the squeezed residue moisture content φ _r on the premise of water addition in this range = 0.35 [%] shows the case of squeezing.
As shown in FIG. 8, the value of D _r / D _f decreases as the value of the moisture content φ _{f ′} after water absorption increases. That is, it is possible enough to increase the amount of water to be absorbed by the palm trunk fragments, to increase the amount of reduction in the residue K concentration D _r for raw material K concentration D _f.
For example, as shown in FIG. 8, if the raw material fragment water content φ _f is 0.6 [−], the water content φ _{f ′} after water absorption is added to 0.8 [−], and _Dr / Since D _f = 0.38, the concentration can be reduced to 38% of the original potassium concentration. On the contrary, when the raw material crushed water content φ _f is 0.6 [−], if the original raw material is only reduced to 50% from the crushed piece concentration, the water content after water absorption φ It shows that it is only necessary to add water for _{f ′} of 0.75 [−]. FIG. 9 shows the concept showing the features at the time of turndown of the hydration process.

Next, the upper limit of the amount of water added per unit mass of the palm trunk fragment will be described. Due to the property restrictions of the raw material moisture content of the palm trunk and the moisture content after water absorption, the water content that has to be most added to the material is that the water content after water absorption is φ when the raw material water content φ _f = 0.6 [-]. _This is a case where _{f ′} = 0.85 [−]. In this case, if the unit water absorption amount La / F _f of the palm trunk fragment is calculated based on the relationship shown in Equation (9), La / F _f = about 1.7.

This is because the amount of water that can be absorbed by the palm trunk fragment is not limited even if the conditions such as the climate and the ratio of soft tissue and vascular bundle contained in the palm trunk fragment vary. It means that the mass is 1.7 times or less. In other words, when the water machine 3 hydrates water of 1.7 times or more of the mass of the palm trunk fragment, it means that the palm trunk fragment cannot be completely absorbed. Therefore, it is preferable that the amount of water added by the water machine 3 is La / F _f = 1.7 or less, thereby preventing excessive water from being added to the palm trunk crushed pieces and waste of water resources.

Next, the properties of palm trunk fragments will be described.

FIG. 11 shows a palm trunk crushed piece crushed by the pulverizer 1 after being dried at 106 [° C.] for 2 hours, and classified by sieving, and mainly composed of soft tissue (hereinafter simply referred to as soft tissue). The weight ratio in each classification range when visually separated into those mainly composed of vascular bundles (hereinafter simply referred to as vascular bundles).
From FIG. 11, it can be seen that the soft tissue has a large particle size distribution between 0.1 and 1.7 [mm], and the vascular bundle is widely distributed in the particle size range of 0.425 to 3.35 [mm]. I understand.
FIG. 12 shows the particle size distribution of the entire palm trunk fragment according to FIG. In addition, the vertical axis | shaft of FIG. 12 displayed the ratio of the weight reference | standard to the whole target object below the particle size shown to a horizontal axis (henceforth only sieving below) when the target object was classified by sieving. Is. Similarly, FIG. 13 shows the particle size distribution for soft tissue and vascular bundles by means of cumulative sieving.
Comparing the soft tissue and vascular bundle graphs in FIG. 13, the particle size distribution profiles are greatly different. This point will be discussed below. If it is ground by the same mechanism, it should have the same particle size distribution. Nevertheless, the fact that the two particle groups have different particle size distributions is produced by different crushing mechanisms. In other words, the group with the larger particle size is directly generated by crushing, whereas the group with the smaller particle size is the one in which the small particles were originally weakly bound by the energy at the time of crushing. This is what is called defibration, which is generated by unraveling to the original particle size state. Therefore, FIG. 13 shows that in the crushing of the palm trunk, the soft tissue, which is the group with the smaller particle size, originally has a particle size distribution, and has been defibrated by being peeled from the vascular bundle by crushing. Is shown.

FIG. 14 is a diagram showing the particle size distribution of the entire palm trunk fragment and the particle size distribution based on the entire fragment of tissue. For example, the total sieve under the vascular bundle with a particle size of 1.0 [mm] or less is 41.2 [%], whereas the total sieve under the soft tissue is 35.6 [%]. The remaining vascular bundles account for 5.6%.

Consider how much the soft tissue is peeled from the vascular bundle in the crushed pieces defibrated by the pulverizer. Since the ratio of the soft tissue in the palm trunk is about 50%, for example, in the crushing as shown in FIG. 11, the ratio of the soft tissue in the crushed piece is 43.5 [%]. It is thought that it is in the state.

Table 1 shows the ratio of the soft tissue and vascular bundle contained in the palm trunk fragment and the water absorption rate. Here, the water absorption rate represents the mass of water that can be absorbed per unit mass of the soft tissue or vascular bundle. The water absorption is determined by dividing the difference between the maximum water absorption weight and the dry weight of the soft tissue or vascular bundle by the dry weight.

Table 2 shows the ratio of the water absorption of the palm trunk crushed pieces of each particle size range classified by sieving to the water absorption of the entire palm trunk. For example, the amount of water absorbed by palm trunk fragments having a particle size of 1.0 [mm] or less accounts for 70.3 [%] of the total amount of water absorption. Further, from the particle size distribution of FIG. 13, 81.8% of the whole soft tissue has a particle size of 1.0 [mm] or less, while a vascular bundle having a particle size of 1.0 [mm] or less is the total vascular bundle. Since it only accounts for 9.9 [%], it can be seen that the water absorption in the palm trunk fragment having a particle size of 1.0 [mm] or less is mainly due to soft tissue.
Moreover, as shown in Table 1, the average water absorption of soft tissue is 7.0 times, and the ratio contained in the palm trunk fragment is 0.435 (43.5 [%]). When these two numbers are multiplied, 7.0 × 0.435≈3.0. Similarly, when the water absorption rate of the vascular bundle is multiplied by the numerical value of the ratio included in the palm trunk fragment, 1.6 × 0.565≈0.90 is obtained. Therefore, the water absorption amount when the total amount of the palm trunk fragment is 1 is 3.0 + 0.90 = 3.90. Since 3.0 ÷ (3.0 + 0.90) ≈0.77, about 77% of the amount of water absorbed in the entire palm trunk fragment is occupied by the amount of water absorbed by the soft tissue. This also indicates that the soft tissue is dominant in the water absorption of the palm trunk fragment.

From Table 2, the ratio of water absorption to the whole in the section where the particle size is 0.1 to 0.3 [mm] is 11.4 [%], so that the total amount of soft tissue and vascular bundle as described above. If the calculation result that the amount of water absorption is 3.9 when 1 is set to 1, the amount of water absorption in this section is calculated as 3.9 × 0.114 = 0.446. On the other hand, as shown in FIG. 11, only the soft tissue exists in the section where the particle diameter is 0.1 to 0.3 [mm], and the ratio to the whole is 5.4 [%]. The water absorption rate of the soft tissue in the section of 1 to 0.3 [mm] is 0.446 / 0.054 = 8.3. This water absorption 8.3 is larger than the average water absorption 7.0 of the whole soft tissue, and shows that the water absorption is maintained without being crushed by the pulverization.
Next, from FIG. 13 and FIG. 14, if the total size of the palm trunk crushed pieces is crushed so that the total sieve size is 35.6 [%] or more, the palm trunk is crushed. As a result, the soft tissue was disentangled, and as a result, the water absorbency of the soft tissue occupying 43.5 [%] of the palm trunk crushed pieces can be used.
Therefore, the cumulative sieve under the particle diameter of 0.3 [mm] of the palm trunk fragment as shown in FIG. 13 is 5.4 [%] or less, and the particle diameter of the palm trunk fragment is 1.0 [mm]. If the total sieving is 35.6 [%] or more, the soft tissue absorbs the soft tissue in the palm trunk fragment and the soft tissue and vascular bundle are defibrated. Thus, water can be absorbed efficiently by utilizing the water absorption of soft tissue.

FIG. 15 is a graph in which the particle size at which the integrated sieve is 50% is read from the graph and written based on the particle size distribution of the vascular bundle and the soft tissue in FIG. Specifically, the particle size at which the total sieving of the soft tissue is 50 [%] is 0.58 [mm], whereas the particle size at which the sieving of the vascular bundle is 50 [%] is 1 47 mm. Since 0.58 ÷ 1.47 ≒ 0.39, when comparing the particle diameters where the total sieving is 50 [%], the soft tissue is 39 [%] (0.39 times) the vascular bundle. Is the diameter. Considering that the mass transfer in the solid is due to diffusion and the time required for the transfer is proportional to the square of the particle size, 0.39 × 0.39≈0.15, so the water absorption time in the soft tissue is This is about 15% of the water absorption time in the vascular bundle. That is, the soft tissue means that the water absorption is completed in a time of only 15 [%] as compared with the vascular bundle.
FIG. 10 shows the time-dependent change of the moisture content of the palm trunk after the immersion of the palm trunk fragment in 20 times the amount of water at a temperature of 25 [° C.]. The water content reaches equilibrium in 5 seconds after the start of immersion. Although this test is data at the time of immersion, the mass transfer of potassium in the palm trunk is the same as at the time of water addition.
From the above, when the palm trunk is pulverized to a soft tissue and vascularized state and then hydrated, the soft tissue quickly absorbs moisture from the soft tissue that is dominant in terms of water absorption. It can be penetrated to the inside. In this case, when water is added to the palm trunk fragment, water absorption can be completed in a very short time.

Next, the operation of the palm trunk processing apparatus 10 will be described.

The pulverizer 1 pulverizes the palm trunk into a powdery palm trunk fragment containing soft tissue and vascular bundles using a hammer mill or the like as described above. Palm trunk fragments obtained by pulverization are transported to the water machine 3. The amount of water Q per unit time of the palm trunk crushed pieces (hereinafter simply referred to as the amount of water Q per unit time) that is hydrated into the palm trunk crushed pieces by the water machine 3 is controlled by the control unit 4.

FIG. 16 is an explanatory diagram of a method for controlling the amount of water Q per unit time by the control unit 4. As shown in FIG. 16, first, in phase 1, initial conditions that are preconditions for controlling the amount of water are set. Specifically, as the conditions of the palm trunk fragments to be hydrated, the processing amount P [kg / h] per unit time of the palm trunk fragments, the raw material moisture content φ _f, and the K concentration D _{f in the} raw materials And set. Moreover, as a condition of the squeezed residue, a squeezed residue moisture content φ _r and a target residue K concentration D _rset (hereinafter simply referred to as a target K concentration D _rset ) are set. These initial setting values are stored in a storage unit included in the control unit 4.

Next, in phase 2, the control unit 4 sets the amount of water Q ₀ [kg / h] per unit unit time by the water machine 3 based on the initial conditions set in phase 1. Q ₀ is calculated by the following formula (10).
Q ₀ = P (φ _{f0 ′} −φ _f ) / (1−φ _{f0 ′} ) (10)
In Equation (10), φ ′ _f0 is the water content after hydrolysis under the initial conditions, and is calculated by Equation (11) below.
φ _{f0 ′} = 1 / {D _rset (1−φ _r ) / (D _f φ _r ) +1) (11)

Next, the control unit 4 resets the water amount Q per unit time by the water machine 3 in the phase 3. Specifically, the amount of water Q per unit time is increased according to the following formula (12). In Formula (12), Q _i is the amount of water added per unit time immediately before, Q _{i + 1} is the amount of water added per unit time after resetting, and ΔQ is the amount of water adjusted per unit time.
Q _{i + 1} = Q _i + ΔQ (12)
In the initial state, Q _i = Q ₀ and ΔQ = 0 are set. In this case, Q _{i + 1} remains Q ₀ and does not change.

Next, in phase 4, the control unit 4 sprays or sprays water from the water machine 3 at a water amount per unit time of Q _{i + 1} .
And the control part 4 reads the outflow amount output from the detection part 5 in phase 5A. Then, the control unit 4 determines whether or not the outflow amount is larger than 0 in the phase 6A, and when the outflow amount is larger than 0, the value of ΔQ is decreased to a negative value. And it returns to phase 3 and resets the amount of water added per unit time. In this way, when the outflow amount is larger than 0, the water amount Q per unit time gradually decreases, so that it is possible to prevent the cost of water resources.
Note that the control unit 4 may decrease the value of ΔQ when the outflow amount is larger than a predetermined amount. Or the detection part 5 may detect the presence or absence of the water | moisture content which was not absorbed by the palm trunk fragment, and the control part 4 may reduce the value of (DELTA) Q, when a water | moisture content is detected by the detection part 5. FIG.

On the other hand, the control unit 4 performs processing of phase 5B in parallel with phase 5A. Specifically, read the value of the analyzer 6 has output the measured residue K concentration D _r. Then, the control unit 4 compares the value of the K concentration D _r in the residue with the value of the target K concentration D _{rset in} the phase 6B. When the value of the K concentration D _{r in} the residue is larger than the target K concentration D _rset , the water amount Q per unit time is reset so that the value of ΔQ becomes positive. When the value of the K concentration D _{r in} the residue is smaller than the value of the target K concentration D _rset , the water amount Q is reset per unit time so that the value of ΔQ becomes negative. If the residue K concentration D _r is equal to the target K concentration D _rset , the value of ΔQ is set to zero. Then, returning to phase 3, the water amount Q per unit time is reset. In this way, since the amount of water Q per unit time is adjusted so that the value of the K concentration D _{r in} the residue approaches the value of the target K concentration D _rset , the amount of water Q per unit time from the water machine 3 is _exceeded. It can be set to a value with no shortage.

In addition, when resetting the amount of water added per unit time in phase 3, the processing result of phase 6A has priority over the processing result of phase 6B. For example, when the outflow amount> 0 in the phase 6A, even if the K concentration D _r in the residue> the target K concentration D _rset in the phase 6B, the control unit 4 makes the value of ΔQ negative. Reset water amount Q per unit time. This is because when the outflow amount is> 0 in Phase 6A, the palm trunk fragment does not absorb all of the water that has been added, so even if the amount of addition is further increased, the residue K concentration _Dr is reduced. It is because it cannot be made to do.

According to the palm trunk treatment method of the present embodiment, the amount of water added per unit time by the water machine 3 is feedback-controlled so that the value of the K concentration D _{r in} the residue becomes the target K concentration D _rset , so It can be carried out. Accordingly, it is possible to prevent water resources from being consumed due to excessive water addition while preventing the amount of water from being insufficient and preventing the K concentration D _r in the residue from exceeding the target K concentration D _rset . In this way, the hydration process can be made more efficient, and limited resources can be effectively utilized when, for example, palm trunks are processed in areas where water resources are not abundant.

As mentioned above, although preferred embodiment of this invention was described referring drawings, this invention is not limited to the said embodiment. The configuration, operation, and the like of the processing device 10 shown in each of the above-described embodiments are merely examples, and various changes can be made based on design requirements and the like without departing from the gist of the present invention.
In addition, the constituent elements in the above-described embodiments can be appropriately replaced with well-known constituent elements without departing from the spirit of the present invention, and the above-described embodiments and modifications thereof may be appropriately combined.

DESCRIPTION OF SYMBOLS 1 ... Crusher 2 ... Juice machine 3 ... Water machine 4 ... Control part 5 ... Detection part 6 ... Analyzer 7 ... Liquid fuel production | generation part 7a ... Juice liquid tank 7b ... Fermenter 7c ... Distiller 7d ... Product tank 8 ... Solid fuel generator 8a ... Dryer 8b ... Crusher 8c ... Molding machine 8d ... Cooler 9 ... Belt conveyor 10 ... Processing device 21 ... Ring roll 22 ... Inscribed roll 23 ... Inlet 24 ... Discharge 25 ... Cylinder 26 ... Press roll

Claims

A pulverization process in which the palm trunk is fibrillated into a soft tissue and a vascular bundle using a pulverizer;
A hydration step of adding water to the palm trunk pulverized in the pulverization step in a range equal to or lower than the upper limit of the amount of water that can be absorbed;
And a squeezing step of squeezing the powdered palm trunk hydrated in the hydration step.
2. The palm according to claim 1, wherein a weight-based cumulative sieve when the palm trunk pulverized in the pulverization step is sieved after drying is 5.4% or less at a particle size of 0.3 mm. How to handle the trunk.
The method for treating a palm trunk according to claim 1 or 2, wherein in the hydration step, the pulverized palm trunk is sprinkled with water or sprayed.
The method for treating a palm trunk according to any one of claims 1 to 3, wherein an amount of water added to the palm trunk in the hydration step is 1.7 times or less with respect to a mass of the palm trunk.
The amount of water added to the palm trunk in the hydration step is controlled based on the potassium concentration contained in the squeezed residue obtained in the squeezing step. How to handle palm trunks.
A palm trunk processing apparatus that implements the palm trunk processing method according to claim 1,
A crusher that defibrates and crushes the palm trunk into soft tissue and vascular bundles,
A water machine for adding water to the palm trunk crushed by the crusher;
A processing device for a palm trunk, comprising: a squeezer that squeezes the palm trunk that has been watered by the water machine.