JP6289789B1 - Oil palm stalk and leaf pretreatment method, biomass fuel production method - Google Patents

Abstract

The present invention provides a pretreatment method for oil palm foliage, which can efficiently remove alkali metals and chlorine from oil palm foliage (OPF). The pretreatment method of the palm foliage according to the present invention includes the step (a) of heating the palm foliage, the step (b) of compressing the palm foliage heated in the step (a), and the step (b). There are a step (c) of washing the squeezed leaves and leaves of the squeezed oil palm with physical impact, and a step (d) of washing and spraying the stalks and leaves of the oil palm washed in the step (c) after draining.

Description

  TECHNICAL FIELD The present invention relates to a method for pretreating oil palm stems and leaves and a method for producing biomass fuel in effectively utilizing oil palm stems and leaves as biomass fuel.

  The world's palm oil production exceeds 55 million tons. In Japan, about 700,000 tons of palm oil is used for food such as instant noodles and non-food such as detergent and soap.

  By the way, from the production process of palm oil and the plantation of oil palm producing palm oil, empty fruit bunches (Empty Fruit Bunches, hereinafter referred to as “EFB” in some cases) remaining after fruit removal from the oil palm fruit bunches. Oil palm trunks that are cut and renewed every 25-30 years (Oil Palm Trunk, sometimes referred to as “palm trunk” or “OPT”), and 2 to 3 are cut off for each oil palm bunches Furthermore, a large amount of oil palm fronds (Oil Palm Frond, hereinafter sometimes referred to as “palm foliage” or “OPF”), which grow 30 to 50 per palm tree trunk, is cut when the palm tree trunk is cut down. .

  EFB has been developed for effective utilization technology for papermaking pulp raw materials and biomass fuel, and OPT has been developed for effective utilization technology such as ethanol conversion of juice. For example, Patent Document 1 below discloses a technique for effectively using EFB as biomass fuel.

  However, oil palm stems and leaves (OPF) exceed EFB and OPT quantitatively, for example, even in Malaysia 1 country, over 40 million tons of dry weight is discharged annually, but it is left in the plantation. However, it is not used for anything other than composting. The reason for this is that OPF is not only large in quantity, but also has individual lengths exceeding 5 m, so it is difficult to carry by human power and needs to be carried by a vehicle. The palm field inhabited by oil palm is largely due to the transportation problem that there is not enough space available for large vehicles at this time.

JP 2010-270320 A

  By the way, biomass power generation is expected to have an effect of suppressing the progress of global warming from the viewpoint of carbon neutrality. For this reason, if oil palm stalks and leaves (OPF) that are not effectively used at this time can be effectively used as fuel for biomass power generation, the chances of actively using OPF will increase, and as described above, It is highly possible that this issue will be resolved for policy reasons.

  Under such a background, the present inventors have conducted intensive research on whether OPF can be used for biomass fuel. As a result, it was confirmed that OPF has an amount of heat equivalent to that of EFB and can be sufficiently used as biomass fuel. On the other hand, the present inventors have confirmed that OPF contains a large amount of alkali metal and chlorine, which are repelling components when used as fuel.

  When biomass fuel containing a large amount of alkali metal is used as a fuel for power generation, the alkali metal causes a chemical reaction in a heating device (power generation boiler) to generate a low melting point material, and the generated low melting point material is, for example, There is a risk of causing troubles such as obstructing the flow of the fluidized bed in the fluidized bed type heating device. Moreover, when biomass fuel containing a large amount of chlorine is used as a fuel for power generation, a low-melting-point substance may be generated in the power generation boiler or the power generation boiler may be corroded in the same manner as alkali metals.

  Therefore, the present inventors have considered that in order to effectively use OPF as biomass fuel, pretreatment for removing alkali metal and chlorine from OPF is necessary. Specifically, the alkali metal content in the fuel is preferably 0.2% by mass or less, and the chlorine content in the fuel is preferably 0.1% by mass or less. However, at present, no consideration has been given to actively using OPF as biomass fuel, and there is no method for efficiently removing alkali metals and chlorine contained in OPF at this time.

  In view of the above problems, an object of the present invention is to provide a pretreatment method for oil palm stems and leaves that can efficiently remove alkali metals and chlorine from oil palm stems and leaves (OPF). Moreover, this invention aims at providing the manufacturing method of biomass fuel using the stem and leaf of the oil palm obtained through this pre-processing method.

The pretreatment method of oil palm stems and leaves according to the present invention is as follows:
Heating the oil palm stalks and leaves (a);
A step (b) of squeezing the palm foliage heated by the step (a);
A step (c) of rinsing the oil palm squeezed by the step (b) with physical impact;
And (d) washing and spraying the oil palm stalks and leaves washed in the step (c).

  Heating the palm foliage in the step (a) softens the plant cells in the palm foliage. As a result, in the subsequent pressing step (b) and water washing step (c), plant cells of oil palm stems and leaves are easily destroyed, and alkali metals and chlorine can be efficiently removed from oil palm palm leaves and leaves. .

  This heating step (a) can be a step of heating using steam. As an example, saturated steam can be used.

  In the method of the present invention, in the squeezing step (b), oil palm stalks and leaves are squeezed to destroy plant cells in the leaves and leaves, and a certain amount of water contained in oil palm stalks and leaves is removed. After the completion of this step (b), it is preferable that the moisture is removed so that the moisture contained in the palm foliage is 60% by mass or less. By this pressing step (b), the alkali metal and chlorine contained in the oil palm stems and leaves are removed from the oil palm stems and leaves together with the pressed water. Furthermore, in this pressing step (b), the plant cells constituting the oil palm stems and leaves are destroyed, whereby the alkali metal and chlorine are easily removed from the oil palm stems and leaves in the subsequent water washing step (c).

  In the method of the present invention, in the water washing step (c), the oil palm stalks and leaves are washed with water while being physically impacted. That is, in this step (c), the plant cells in the oil palm stems and leaves are washed with water while being destroyed. Thereby, the alkali metal and chlorine in the stem and leaf of the oil palm which were not squeezed in the pressing process (b) can be eluted in the washing water.

  The physical impact in the water washing step (c) may be due to continuous (continuous) pressurization, but may be due to intermittent impact applied intermittently. By employing the latter, the time required for the water washing step (c) can be minimized.

  In the method of the present invention, in the water sprinkling washing step (d), the water is washed with water after draining the oil palm stalks and leaves after the water washing step (c) is completed. By this step (d), the alkali metal and chlorine dissolved in the water adhering to the surface of the palm foliage can be removed.

  In this sprinkling washing step (d), water (water after washing) after being sprinkled on the oil palm stems and leaves is dissolved in comparison with the water after washing the oil palm stems and leaves in the water washing step (c). Less alkali metal and chlorine. For this reason, after collect | recovering the water used by the sprinkling washing process (d), it is good also as what is utilized for the washing water of a water washing process (c). Thereby, while the total amount of water used by the method of this invention is reduced, the drainage process of the water after using it at a sprinkling washing process can be abbreviate | omitted or simplified.

  By the way, there are large oil palm stalks and leaves exceeding 5 m. The pressing step (b) is performed by, for example, putting oil palm stalks and leaves into a pressing machine and operating them. For this reason, when large-sized oil palm stalks and leaves are directly put into the squeezing machine, the oil palm stalks and leaves themselves may be too large to be squeezed sufficiently in the squeezing machine or may not be put into the squeezing machine in the first place. For this reason, in the said method, before execution of a pressing process (b), you may have a process (e) which crushes the palm foliage so that a long fiber length may be 300 mm or less. This crushing step (e) may be performed before the heating step (a), or may be performed after the heating step (a) and before the pressing step (b). .

  In the above method, in the water washing step (c), the oil palm stems and leaves are washed with water in an amount of 3 parts by mass or more and 22 parts by mass or less with respect to 1 part by mass (dry mass) of the oil palm stems and leaves to be washed. It does n’t matter what you do. Similarly, in the sprinkling washing step (d), with respect to 1 part by mass (dry mass) of the oil palm foliage to be sprinkled, the oil palm foliage is added at a water spray amount of 3 parts by mass or more and 20 parts by mass or less. It does not matter even if it is washed with water. By performing water washing / watering washing with the amount of water within this range, the effect of removing alkali metals and chlorine is exhibited while suppressing the amount of water used within a certain range.

  The said method WHEREIN: It is good also as what has the process (f) which squeezes the said stalks and leaves of the said oil palm after the said process (d) further.

  As described above, at least a part of the plant cells of the palm foliage is destroyed through the pressing step (b) and the water washing step (c). For this reason, a part of the water (washing water / washing water) supplied to the palm foliage by the water washing step (c) and the sprinkling washing step (d) may be taken into the plant cells of the oil palm foliage. . As described above, after the water spray washing step (d) is completed, the squeezing step (f) is performed again, so that the water contained in the plant cells of the oil palm stems and leaves is taken out and dissolved in the water. Alkali metal and chlorine are removed. As a result, alkali metals and chlorine can be further removed from the palm foliage.

In the above method, after the step (f), the step (g) of further washing the oil palm stems and leaves with watering;
After the step (g), it may have a step (h) of further squeezing the palm leaves.

  By carrying out these steps (g) and (h), it is possible to further remove alkali metals and chlorine adhering to the surface of oil palm stems and leaves, and to contain them in the destroyed plant cells. In addition, trace amounts of alkali metals and chlorine remaining inside the oil palm stems and leaves can be further removed.

Moreover, the method for producing biomass fuel according to the present invention includes:
After completion of the above-mentioned pretreatment method for oil palm stalks and leaves, the step (i) of drying the oil palm stalks and leaves until moisture contained in the oil palm stalks and leaves is 20% by mass or less;
After the step (i), there is a step (j) of molding the dried palm palm leaves into pellets.

  According to the above method, oil palm stalks and leaves can be suitably used as biomass fuel in a state where alkali metals and chlorine are sufficiently removed. In the step (j), the pellet size may be set to a bulk density of 0.50 kg / L or more. The size of the pellet can be set as appropriate in consideration of transportation efficiency and handling properties.

  In the above method, a step (k) may be provided between the step (i) and the step (j) to crush the palm foliage until the long fiber length is 20 mm or less. By executing this step (k), the palms and leaves of the oil palm are reduced in size, and the execution of the molding step (j) is facilitated.

  In the step (j), the oil and fat derived from the oil palm stems and leaves obtained after the completion of the above-described method for pretreatment of the oil palm stems and leaves may be used as a molding aid. By using this oil and fat, the calorie | heat amount of a pellet can be increased, improving the utilization efficiency of the foliage of an oil palm.

  According to the method of the present invention, alkali metal and chlorine can be efficiently removed from oil palm stems and leaves (OPF), and oil palm stems and leaves that have not been effectively used at the present time can be used for biomass fuel.

It is a flowchart which shows typically the pre-processing method of the stem and leaf of the oil palm which concerns on this invention, and the manufacturing method of biomass fuel. It is a block diagram which shows typically an example of the apparatus which implements the method shown by the flowchart of FIG. It is a flowchart which shows typically the aspect of another embodiment of the pre-processing method of the palm foliage which concerns on this invention, and the manufacturing method of biomass fuel. It is a block diagram which shows typically an example of the apparatus which implements the method shown by the flowchart of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a pretreatment method for oil palm stems and leaves and a method for producing biomass fuel according to the present invention will be described with reference to the drawings as appropriate.

  FIG. 1 is a flowchart schematically showing an embodiment of a pretreatment method for oil palm stems and leaves and a method for producing biomass fuel according to the present invention. FIG. 2 is a block diagram schematically showing an example of an apparatus (hereinafter referred to as a “biomass fuel conversion apparatus”) for carrying out the oil palm pretreatment method and the biomass fuel production method according to the present invention. is there. In FIG. 2, the flow of biomass material is indicated by a solid line with an arrow, and the flow of liquid (water or oil) is indicated by a broken line with an arrow.

  As FIG. 1 shows, the manufacturing method of the biomass fuel which concerns on this invention is comprised including step S10 corresponding to a pre-processing process, and step S20 corresponding to a post-processing process.

  In the example shown by FIG. 1, pre-processing process S10 is provided with heating process S11, pressing process S12, water washing process S13, sprinkling washing process S14, and pressing process S15. The post-processing step S20 includes a drying step S21, a crushing step S22, and a molding step S23.

  Moreover, as FIG. 2 shows, the biomass fuel conversion apparatus 1 of this embodiment has the pre-processing apparatus 2 and the post-processing apparatus 3, and is comprised. The pretreatment device 2 includes a heater 11, a hopper 12, a squeezing machine 13, a washing device 14, a vibrating sieve 15, a vibrating sieve 16, a washing water supply device 17, a waste washing water tank 18, a water pump 19, and washing water. It is comprised including the supply apparatus 21, the oil-water separator 22, the waste water treatment apparatus 24, and the pressing machine 25. FIG. The post-processing device 3 includes a dryer 32, a crusher 33, a molding machine 34, and an oil feed pump 35.

  Hereinafter, each process will be described in detail with reference to FIG.

[Pretreatment process]
First, the pretreatment step S10 will be described.

(Heating step S11)
First, oil palm stems and leaves e1 collected from a plantation or the like are put into the heater 11 and heated in the heater 11. Oil palm stalk and leaf e1 contains a large amount of potassium among alkali metals, and the content thereof is 0.2 to 0.5 mass% for the leaf portion and 0.8 to 1.3 mass% for the stem portion. . The chlorine content is 0.2 to 0.4 mass% for the leaf portion and 0.1 to 0.6 mass% for the stem portion. And this oil palm stalk and leaf e1 contains 60-70 mass% of water | moisture content.

  Oil palm foliage e2 after heating is in a state where the plant cells are softened. It is preferable that the degree of softness of the oil palm stalks and leaves e2 after heating should be flexible so that the handling in the subsequent steps is not hindered. More specifically, in this heating step S1, it is preferable to heat using saturated steam at 100 to 200 ° C. for 15 to 60 minutes.

  The heating device 11 is not limited to the device mode and the heating principle as long as the heated oil palm stems and leaves e2 are soft and can be easily handled. However, the heating device 11 is heated using steam or saturated steam. It is preferable to do this. As an example, the heater 11 may be a general device for softening a plant, such as a steamer, a steamer, a warm air device (dryer), or a hot water reservoir (pot). Among these, it is preferable to use a steamer or a steamer because the palm foliage e1 can be sufficiently softened in a short time.

  By the way, oil palms inhabit many rainforest climate zones such as Malaysia and Indonesia. In these regions, there are cases where plant cells can be sufficiently softened by simply placing oil palm foliage e1 in the field for a period of about two weeks. In such a case, the step of piling up the palm foliage e1 for a certain period corresponds to the heating step S11, and the pretreatment device 2 does not necessarily have to include the heater 11.

  This heating step S11 corresponds to the step (a).

(Pressing step S12)
Oil palm stems and leaves e2 softened through the heating step S11 are put into the hopper 12 and stored. The oil palm stalks and leaves e2 are appropriately supplied from the hopper 12 to the press 13 at a predetermined flow rate (speed).

  The press machine 13 pressurizes the stalks and leaves e2 of the input palm to destroy the plant cells of the stalks and leaves e2 of the oil palm that have already been softened, and also converts the alkali metal and chlorine contained in the plant cells to moisture. Squeeze together. At this time, it is preferable that the pressing machine 13 squeezes the water content of the oil palm stalks and leaves e3 to 60 mass% or less, and is not limited to this type as long as it can be squeezed within this range. As an example, the pressing machine 13 can use general-purpose devices such as a hydraulic press machine (vertical type, horizontal type), a uniaxial pressing machine (screw type), and a biaxial pressing machine (extruder). Among these, it is preferable to use a biaxial press (extruder) because the required time is short and continuous processing is possible.

  By this squeezing step S12, water in which alkali metal and a part of chlorine contained in the plant cells of the oil palm foliage e2 are squeezed out from the oil palm foliage e2 and discharged. As a result, the content of alkali metals and chlorine in the oil palm foliage e3 after the completion of the compression step S12 is lower than that in the oil palm foliage e2 before the compression step S12 is executed.

  By the way, most of the alkali metals and chlorine contained in the oil palm stems and leaves e3 after the completion of the pressing step S12 are dissolved in the water contained in the oil palm stems and leaves e3. Therefore, it can be said that the alkali metal and chlorine contents of the oil palm stems and leaves e3 are proportional to the residual water content of the oil palm stems and leaves e3. That is, the residual water content of the oil palm stems and leaves e3 can be used as an index of the contents of alkali metals and chlorine contained in the oil palm stems and leaves e3. Furthermore, the residual water content of the oil palm stems and leaves e3 is also an index of the degree of destruction of the plant cells of the oil palm stems and leaves e2 by the press 13, and the smaller the residual water content, the greater the amount of destroyed plant cells. Means.

  From the viewpoint of reducing the alkali metal and chlorine content, and from the viewpoint of destroying many plant cells, the residual moisture content of the oil palm stems and leaves e3 is preferably 60% by mass or less, more preferably 55% by mass or less, and 50% by mass. The following are particularly preferred: If the residual water content of the oil palm stems and leaves e3 is 60% by mass or less, the alkali metal content is 0.2% by mass or less through the water washing step S13 and the watering washing step S14 performed thereafter, and Oil palm foliage having a chlorine content of 0.1% by mass or less can be obtained. In addition, the alkali metal content of oil palm stalks and leaves e3 having a residual water content of 60% by mass is 0.2 to 0.8% by mass, and the chlorine content is 0.1 to 0.5% by mass.

  In the present embodiment, discharged water (hereinafter referred to as “pressed water”) SW <b> 1 obtained by executing the pressing step S <b> 12 is sent to the oil-water separator 22. The oil / water separator 22 separates the supplied compressed water SW1 into moisture W3 and an oil / fat content O1. The oil-water separator 22 is not limited to its form as long as it can realize a function of separating moisture and fats and oils from a liquid in which moisture and fats and oils are mixed. For example, as the oil / water separator 22, an oil / water separator and a centrifugal deoiler can be used. From the viewpoint of cleaning the water W3 discharged out of the system after the waste water treatment, the centrifugal deoiler by high-speed centrifugation is used. Is preferably used.

  This pressing step S12 corresponds to the step (b).

(Washing step S13)
The stalks and leaves e3 of the oil palm after the squeezing step S12 is completed are sent to the water washing device 14, and the water washing step S13 is executed in the water washing device 14. The water washing step S13 is a step of washing the oil palm stems and leaves e3 with physical impact on the oil palm stems and leaves e3 and destroying the plant cells of the oil palm stems and leaves e3. The rinsing device 14 is supplied with the rinsing water W1 from the rinsing water supply device 21, and uses this rinsing water W1 to wash the oil palm stems and leaves e3. The flush water supply device 21 includes a tank for storing the flush water W1 and a water inlet for sending the stored flush water W1 to the flush device 14 at a predetermined flow rate.

  More preferably, the water washing apparatus 14 has a configuration capable of performing water washing while intermittently applying an instantaneous physical impact to the palm foliage e3. For example, the rinsing device 14 is a cylindrical device to which the rinsing water W1 is supplied from the rinsing water supply device 21, and is physically attached to the rotating mechanism that rotates in the axial direction and the oil palm stalk e3 accommodated in the device. It is possible to adopt a configuration including an impact medium that gives a mechanical impact.

  As a specific example, the rinsing device 14 is a cylindrical device to which the rinsing water W1 is supplied from the rinsing water supply device 21, and has a shaft provided with a plurality of paddles inside the device. The shaft is configured to be rotatable. Such an apparatus may be referred to as a paddle mixer. Oil palm foliage e3 is supplied into the apparatus from the vicinity of one end of the apparatus, and flows to the vicinity of the other end of the apparatus in accordance with the flow of washing water W1. In this way, the palm foliage e3 is crushed by the paddle when it passes through the installation location of the paddle while moving in the water washing apparatus 14. As a result, each time it passes through the place where the paddle is provided, the stalks and leaves e3 of the oil palm are washed with water in the rinsing apparatus 14 while receiving a momentary impact. In this aspect, the paddle corresponds to the impact medium.

  The water-washing device 14 is not limited to the paddle mixer as described above as long as the water-washing device 14 can perform water-washing while applying a physical impact to the palm foliage e3. As another example, a desalt separator to which flush water W1 is supplied from the flush water supply device 21 can be used. The desalt separator is a drum-like container having a lifter on the inner surface that rotates about an axis extending in the horizontal direction or an axis slightly inclined from the horizontal direction, and is movably accommodated in the container. It is a device that has multiple iron bars and has the functions of both a drum washer and a rod mill. The plant cells of the oil palm foliage e3 are destroyed by the impact of the iron bar falling after being lifted by the lifter, and the oil palm foliage e3 can be efficiently crushed by the weight of the iron bar and the stirring effect by the rotation of the container.

When the water washing apparatus 14 is configured with a desalt separator, the length of the iron rod as the impact medium is substantially the same as the length of the sample chamber of the water washing apparatus 14 with respect to the volume Am ³ of the sample chamber of the water washing apparatus 14. It is preferable to use 4 to 10 rod-shaped members having a volume of 0.015 A to 0.04 Am ³ , and more preferably 5 to 8 rod members. The impact medium can be a spherical member. In this case, it is preferable to use a member having a diameter of 25 mm or more at a filling rate of 7 to 15%.

  As another example of the water washing apparatus 14, a wet trommel can be adopted. Further, the water washing device 14 does not necessarily need to include an impact medium, and includes only a rotating device. By stirring the oil palm foliage e3 in the rotating device, the water washing device 14 is directed toward the inner surface of the rotating device by its own weight. It is also possible to adopt a configuration in which a physical impact is given to the palm foliage e3 by dropping it multiple times.

  The amount of the rinsing water W1 used in this rinsing step S13 is the coconut oil to be washed from the viewpoint of efficiently removing alkali metals and chlorine from the palm foliage e3 and the amount of rinsing water W1 used. Preferably, 2 to 13 parts by mass (based on 1 part by mass of oil palm foliage e3 on a dry mass basis (hereinafter referred to as “dry base”), 3 to 22 parts by mass with respect to 1 part by mass of More preferably, it is 3 to 5 parts by mass (5 to 8 parts by mass on a dry basis).

  Moreover, since this washing water W1 is used for dissolving and removing the alkali metal and chlorine contained in the palm foliage e3, it is most preferably water not containing alkali metal and chlorine. . However, as described above, the alkali metal and chlorine concentrations in the water contained in the palm foliage e3 are as high as 0.2 to 0.8 mass% and 0.1 to 0.5 mass%, respectively. The alkali metal and chlorine content of the washing water W1 should just be 0.1 mass% or less. Therefore, from the viewpoint of suppressing the amount of waste water treated in the waste water treatment device 24 described later, in this embodiment, the waste water for washing W5 used in the next sprinkling washing step S14 is used as the flush water W1. be able to. As will be described later, the alkali metal and chlorine content of the waste water W5 is 0.02% by mass or less, and is within a range that can be used as the water W1.

  This water washing step S13 corresponds to the step (c).

(Sprinkling washing process S14)
The oil palm stalks and leaves e4 after completion of the water washing step S13 are drained and then subjected to watering washing. More specifically, it is as follows.

  The palm foliage e4 after completion of the water washing step S13 is supplied to the vibrating sieve 15 together with the water (drainage washing water W2) after being used in the water washing step S13. The vibration sieve 15 does not allow the palm foliage e4 to pass therethrough, and is provided with a plurality of holes having a size that allows water (drainage washing water W2) to pass therethrough. Therefore, the mixture of the oil palm stems and leaves e4 and the drainage washing water W2 supplied to the vibration sieve 15 is washed with the oil palm stems and leaves e4 remaining on the upper surface of the vibration sieve 15 and the lower surface of the vibration sieve 15. Separated into water W2.

  Thereafter, the oil palm stems and leaves e4 remaining on the upper surface of the vibrating screen 15 are moved to the vibrating screen 16 provided in connection with the vibrating screen 15. In the vibration sieve 16, the cleaning water W <b> 4 supplied from the cleaning water supply device 17 is sprinkled on the palm foliage e <b> 4. The cleaning water supply device 17 includes a tank for storing the cleaning water W <b> 4 and a sprinkling water inlet for spraying the stored cleaning water W <b> 4 toward the vibrating sieve 16.

  As the washing water W4 used in the sprinkling washing step S14, it is preferable to use an alkali metal and chlorine content of 0.01% by mass or less. Moreover, the amount of water sprayed from the washing water W4 is preferably 2 to 12 parts by mass (3 to 20 parts by mass on a dry base), more preferably 3 to 5 parts by mass, with respect to 1 part by mass of the palm foliage e4. Part (5 to 8 parts by mass on a dry basis).

  By the sprinkling washing step S14, water in which the alkali metal and / or chlorine is dissolved and adhered to the surface of the oil palm stems and leaves e4 after completion of the water washing step S13 is washed away. As a result, after completion of the sprinkling washing step S14, that is, the palm foliage e5 supplied from the vibrating sieve 16 has an alkali metal content of 0.2% by mass or less and a chlorine content of 0.1% by mass or less. descend.

  As with the vibration sieve 15, the vibration sieve 16 does not allow the palm foliage e5 to pass therethrough and is provided with a plurality of holes having a size that allows water (exhaust washing water W5) to pass therethrough. As a result, a certain amount or more of the cleaning water W4 (exhaust cleaning water W5) adhering to the surface of the oil palm stems and leaves e5 is shaken off by the vibrating screen 16, and the oil palm stems and leaves e5 are drained. The vibration sieve 16 applies moisture to the oil palm stems and leaves e5 so as to visually confirm that no large water droplets remain on the oil palm stems and leaves e5 by, for example, applying vibration to the oil palm stems and leaves e5. Remove it.

  The screens of the vibrating screen 15 and the vibrating screen 16 separate and collect water and oil palm stems and leaves, and more specifically, the waste water washing water W2 and oil palm stems and leaves e4, and the waste water washing water W5 and oil palm. In order to separate and recover the stems and leaves e5, the nominal aperture is preferably 4 mm or less, more preferably 2.8 mm or less.

  In the present embodiment, the vibration sieve 15 and the vibration sieve 16 are described as being connected to each other. However, if the drainage of the oil palm stems and leaves e4 and the drainage of the oil palm stems and leaves e4 after the water draining and the water drainage of the oil palm stems and leaves e5 after the completion of the water spray cleaning process can be performed with a single vibrating sieve. It doesn't matter. That is, drainage of the oil palm stems and leaves e4 may be performed on the upstream side of one vibration sieve, and water spray washing and drainage may be performed on the oil palm stems and leaves e4 on the downstream side.

  In the present embodiment, the waste water washing water W2 distributed by the vibration sieve 15 is sent to the oil / water separator 22 described above. In the oil / water separator 22, the mixed fluid of the compressed water SW1 discharged from the press 13 and the waste water washing water W2 is separated into the water W3 and the oil / fat content O1. In addition, it is good also as a structure which provides separately the mechanism which isolate | separates the compressed water SW1 and oil water, and the mechanism which isolate | separates the waste water F2 wash water W2.

  In the present embodiment, the waste washing water W5 distributed by the vibrating screen 16 is collected and stored in the waste washing water tank 18. Part of the waste washing water W5 stored in the waste washing water tank 18 is supplied to the washing water supply device 21 by the water pump 19 and circulated and used as the washing water W1. Further, the other part of the waste water W5 is supplied to the waste water treatment device 24. The water pump 19 is not particularly limited as long as it is a liquid pump, and a general-purpose device such as a spiral pump or a piston pump can be used.

  This watering washing process S14 respond | corresponds to the said process (d).

(Pressing step S15)
In the present embodiment, the palm stems and leaves e5 after the sprinkling washing step S14 is completed are supplied to the pressing machine 25, and the pressing step is executed again. The pressing machine 25 is provided to pressurize the oil palm stems and leaves e5 and squeeze out the washing water W4 or the waste washing water W5 contained in the oil palm stems and leaves e5. The press 25 is not particularly limited as long as it can squeeze the water content of the oil palm stalks and leaves e6 to 70% by mass or less. Similarly to the press 13, the hydraulic press (vertical type, horizontal type), General-purpose devices such as a single screw press (screw type) and a twin screw press (extruder) can be used.

  Oil palm stalks and leaves e6 whose water content is reduced to 70% by mass or less by the press 25 are reduced to an alkali metal content of 0.1% by mass or less and a chlorine content of 0.05% by mass or less.

  The compressed water SW2 discharged from the pressing machine 25 is supplied to the waste water treatment device 24. The waste water treatment device 24 is also supplied with the water W 3 separated by the oil / water separator 22 and the waste washing water W 5 stored in the drain tank 18. The water W3, the waste washing water W5 and the compressed water SW2 supplied to the waste water treatment device 24 are discharged out of the system as waste water W6 after appropriate waste water treatment. Thereby, wastewater treatment can be performed collectively in one place in the wastewater treatment device 24. Here, the water W3, the waste water W5 and the compressed water SW2 have high BOD (biological oxygen demand), COD (chemical oxygen demand) and SS (suspension matter), so the waste water treatment device 24. It is preferable to use a sedimentation tank or an activated sludge tank (aeration tank).

  This pressing process S15 respond | corresponds to a process (f).

  According to the pretreatment step S10 of the present invention, oil palm foliage e5 having an alkali metal content of 0.2% by mass or less and a chlorine content of 0.1% by mass or less can be obtained. Furthermore, like this embodiment, by performing pressing process S15 after sprinkling washing process S14, alkali metal content is 0.1 mass% or less, and chlorine content is 0.05 mass% or less. The foliage e6 can be obtained.

[Post-processing process]
Next, the post-processing step S20 will be described.

(Drying step S21)
The oil palm foliage e6 after the pretreatment step S10 is performed is put into the dryer 32, and the moisture in the dryer 32 is preferably 20% by mass or less, more preferably 17% by mass or less. Dried. The dryer 32 is not particularly limited as long as it can dry the palm foliage e6 to a moisture content of 20% by mass or less, but a rotary dryer capable of continuous operation can be preferably used.

  Although depending on the environment such as temperature and humidity, it is possible to dry the oil palm foliage e6 to a moisture content of 20% by mass or less even by sun drying. In this case, it is not necessary to use the dryer 32 to execute the drying step S21.

  According to the dried oil palm stalks and leaves e7 obtained through the drying step S21, since the water content is reduced, the working efficiency of the subsequent crushing step S22 and the molding step S23 can be improved. Thereby, the quality of the obtained biomass fuel is homogenized and the quality change by the moisture of the obtained biomass fuel is suppressed.

  This drying step S21 corresponds to the step (i).

(Crushing step S22)
The oil palm foliage e7 after the drying step S21 is completed is supplied to the crusher 33 and transformed into oil palm foliage e8 having a long fiber length of 20 mm or less. As the crusher 33, general facilities, such as a uniaxial crusher and a biaxial crusher, can be used.

  This crushing step S22 is a step for crushing the palm foliage e7 after completion of the drying step S21 to improve the work efficiency of the subsequent molding step S23. Oil palm foliage e7 after completion of the drying step S21 may include those having a long fiber length of up to about 300 mm. Therefore, in this crushing step S22, the oil palm foliage e7 is crushed, preferably 20 mm. In the following, it is transformed into oil palm stems and leaves e8 of 10 mm or less. However, in the molding step S23, which will be described later, this crushing step S22 may be omitted if molding is possible with the oil palm stems and leaves e7 after the completion of the drying step S21.

  This crushing step S22 corresponds to the step (k).

(Molding step S23)
Oil palm foliage e8 after the crushing step S22 is completed is supplied to the molding machine 34 and transformed into pellets (biomass fuel) e9. By this molding step S23, a pellet-shaped biomass fuel e9 having a bulk density of 0.50 kg / L or more, a compressive strength of 1.5 N / mm ² or more, and a calorie of 3500 kcal / kg or more is generated. The bulk density is in accordance with the test method specified in JISZ 7302-9 “Waste Solidified Fuel-Part 9: Bulk Density Test Method”, and the crushing strength is in JIS Z 8841 “Granulated Material—Strength Test Method”. The amount of heat in the specified test method is a measured value obtained by a test conforming to the test method specified in JIS Z 7302-2 “Waste Solidified Fuel—Part 2: Calorific Value Test Method”.

  In this embodiment, sludge-like oil and fat content O1 obtained by being separated by the oil-water separator 22 is supplied by the oil feed pump 35 to the oil palm water and stem e8 in the molding machine 34. This oil and fat content O1 is used as a molding aid in the molding machine 34. Since the fat and oil component O1 has a calorie | heat amount, the calorie | heat amount of the biomass fuel e9 after shaping | molding can be increased by supplying and molding this to the palm foliage e8. However, when the content of alkali metal and / or chlorine contained in the fat and oil component O1 is large, the fat and oil component O1 may not be used as a molding aid.

  The size of the pellet can be appropriately determined in consideration of transportation efficiency and handling properties. The molded biomass fuel e9 can be used as a solid fuel in a power generation CFB (circulating fluidized bed) boiler device or the like, or can be used as a coal substitute fuel in a cement firing device or the like.

  This molding step S23 corresponds to the step (j).

[Example]
An embodiment of a preprocessing method using the preprocessing device 2 will be described with reference to Table 1. In addition, the potassium content shown in Table 1 is a result of measuring a solution obtained by completely dissolving a sample with an acid by ICP emission spectroscopy. The chlorine content is a test result obtained in accordance with the test method of JISZ 7302-6 “Waste Solidified Fuel—Part 6: Total Chlorine Content Test Method”. Moreover, the value without parentheses in the removal rate column for potassium and chlorine in Table 1 indicates the total removal rate (mass%) up to each step, and the value in parentheses is the removal rate (mass%) from the previous process. Is shown.

  According to Table 1, when the sprinkling washing step S14 is completed, the alkali content of oil palm stalks and leaves is 0.16% by mass, and the chlorine content is 0.075% by mass. Furthermore, when pressing process S15 is performed after that, the alkali content of the palm foliage is 0.08 mass%, and chlorine content is 0.025 mass%.

  As described above, according to the pretreatment step S10 of the present invention, the alkali content of oil palm stalks and leaves can be reduced to 0.2 mass% or less and the chlorine content to 0.1 mass% or less.

[Another embodiment]
Hereinafter, another embodiment will be described.

  <1> In the embodiment described above, in the pretreatment step S10, the squeezing step S15 is performed after the completion of the sprinkling washing step S14. However, the squeezing step S15 may be omitted. FIG. 3 shows a flowchart corresponding to this alternative embodiment in accordance with FIG. 1, and FIG. 4 shows an example of the configuration of an apparatus for executing the method of this alternative embodiment in accordance with FIG. It is illustrated. As shown in FIG. 4, in this configuration, the oil palm stems and leaves e5 after the water is distributed by the vibrating sieve 16 are supplied to the dryer 32, and the drying step S21 is executed.

  As described above, even if the pressing step S15 is not performed, the palm foliage e5 obtained after the completion of the sprinkling washing step S14 has an alkali content of 0.2% by mass or less and a chlorine content of 0.1. It can be made into mass% or less. In addition, in this another embodiment, since the pressing machine 25 shown in FIG. 2 is not provided, the waste water treatment device 24 is supplied with moisture W3 and waste washing water W5.

  <2> Before the pressing step S12, a step of crushing oil palm stems and leaves may be further provided. Specifically, the pretreatment device 2 includes a crusher similar to the crusher 33, and before the crusher is put into the oil palm foliage e <b> 1 before being put into the heater 11, or the press machine 13. The palm foliage e2 may be crushed so that the long fiber length is 300 mm or less. Thereby, the pressing process in the pressing machine 13 can be performed efficiently.

  This crushing step corresponds to step (e).

  <3> In FIG. 1, after the pressing step S15, the sprinkling washing step S14 and the pressing step S15 may be repeated once or a plurality of times. Thereby, the trace amount alkali metal and chlorine which remain | survive in the inside of the palm foliage e6 can further be removed. Sprinkling washing process S14 performed again after execution of pressing process S15 respond | corresponds to a process (g), and pressing process S15 performed after that corresponds to a process (h).

  <4> In the above embodiment, the waste washing water W5 is circulated and supplied to the washing water supply device 21 so as to be used as the washing water W1, but this aspect is arbitrary. That is, all the waste washing water W5 may be discharged to the waste water treatment device 24.

  <5> In the above embodiment, the compressed water SW2 discharged from the pressing machine 25 is supplied to the waste water treatment device 24. However, the water W3 passes through the oil-water separator 22 in the same manner as the compressed water SW1. May be supplied to the wastewater treatment device 24, and the oil and fat O1 may be supplied to the molding machine 34.

  <6> In the above embodiment, whether or not the oil and fat component O1 separated by the oil / water separator 22 is supplied to the molding machine 34 is arbitrary.

1: Biomass fuel conversion device 2: Pretreatment device 3: Posttreatment device 11: Heater 12: Hopper 13: Squeezer 14: Flushing device 15: Vibrating sieve 16: Vibrating sieve 17: Washing water supply device 18: Waste washing water Tank 19: Water pump 21: Flushing water supply device 22: Oil-water separator 24: Waste water treatment device 25: Squeezer 32: Dryer 33: Crusher 34: Molding machine 35: Oil pump

Claims (13)

Heating the oil palm stalks and leaves (a);
A step (b) of squeezing the palm foliage heated by the step (a);
A step (c) of rinsing the oil palm squeezed by the step (b) with physical impact;
And a step (d) of spraying and washing the oil palm stalks and leaves washed in the step (c) after draining.   2. The oil palm foliage according to claim 1, further comprising a step (e) of crushing the oil palm stems and leaves so that a long fiber length is 300 mm or less in a step prior to the step (b). Pre-processing method.   The said process (a) is a heating process using a steam | vapor, The pre-processing method of the foliage of the oil palm of Claim 1 or 2 characterized by the above-mentioned.   The said process (b) is a process of removing so that the water | moisture content contained in the said palm foliage may be 60 mass% or less, The palm foliage of any one of Claims 1-3 characterized by the above-mentioned. Pre-processing method.   The step (c) is a step of washing with water while repeatedly applying the momentary physical impact to the palm foliage, wherein the palm foliage according to any one of claims 1 to 4 is characterized. Pre-processing method.   The step (c) is a step of washing the oil palm stems and leaves with a water amount of 3 parts by mass or more and 22 parts by mass or less with respect to 1 part by mass (dry mass) of the oil palm stems and leaves to be washed. The pretreatment method of the palm foliage of any one of Claims 1-5 characterized by the above-mentioned.   The step (d) is a step of sprinkling and washing the oil palm stems and leaves with a water spray amount of 3 parts by mass or more and 20 parts by mass or less with respect to 1 part by mass (dry mass) of the oil palm stems and leaves to be watered. The pretreatment method for oil palm stalks and leaves according to any one of claims 1 to 6.   In the said process (c), the water after the washing | cleaning water used by the said process (d) is collect | recovered is used, The palm foliage of any one of Claims 1-7 characterized by the above-mentioned. Pre-processing method.   The method for pretreating oil palm foliage according to any one of claims 1 to 8, further comprising a step (f) of further pressing the oil palm foliage after the step (d). After the step (f), the step (g) of further washing the oil palm stems and leaves with watering;
The method for pretreating oil palm stems and leaves according to claim 9, further comprising a step (h) of further pressing the oil palm stems and leaves after the step (g). A step of drying the oil palm stalks and leaves until the moisture contained in the oil palm stalks and leaves is 20% by mass or less after completion of the pretreatment method of oil palm stalks and leaves according to any one of claims 1 to 10. i) and
A method for producing biomass fuel, comprising the step (j) of forming the dried palm oil leaves into pellets after the step (i).   The biomass according to claim 11, further comprising a step (k) of crushing the palm leaves and leaves until the long fiber length is 20 mm or less between the step (i) and the step (j). Fuel manufacturing method.   The step (j) is a step of using, as a molding aid, the oil and fat derived from the oil palm foliage obtained after completion of the pretreatment method for oil palm foliage according to any one of claims 1 to 10. The method for producing a biomass fuel according to claim 11 or 12, wherein:

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