JP6343379B1 - Solid biomass fuel and production method thereof - Google Patents

Abstract

In order to further reduce potassium and chlorine in solid biomass fuel, a method for removing potassium and chlorine from plant raw materials has been studied. SOLUTION: Solid biomass fuel 411 produced from a plant raw material 121, and the plant raw material 121 is pulverized and agitated in hot water and then rinsed, and then potassium and chlorine are eluted in the hot water. It is preferable to fry in oil in a state in which potassium and chlorine are eluted and in a state of being formed into pellets 341. [Selection] Figure 1

Description

  The present invention relates to a solid biomass fuel produced from a plant material and a production method thereof.

  In recent years, solid biomass fuels produced from various plant materials have been proposed. When solid biomass fuel uses heat generated by combustion (for example, it is used as fuel for a thermal power plant), there is a problem that the contained potassium and chlorine cause high temperature corrosion of the boiler. Patent Document 1 proposes a removal method (modification method) for dehydrating the plant raw material after the atomized plant raw material is immersed in atmospheric water (Patent Document 1 [Claim 1]). The normal-pressure water may be hot water (Patent Document 1 [Claim 1]). As a result, water-soluble potassium and chlorine are eluted in water or hot water and removed from the plant material (Patent Documents 1 [0022] [0023]).

JP2016-125030A

  The plant raw material disclosed in Patent Document 1 is sent to a dehydrator together with an aqueous solution from which potassium and chlorine are eluted, dehydrated to 25% or less, and then pelletized (Patent Document 1 [0038] [0039]). Thus, the plant raw material which patent document 1 discloses contains the water | moisture content which potassium and chlorine eluted, even if pelletized, and will contain the eluted potassium and chlorine as solid biomass fuel, and is unpreferable. Then, the method of removing potassium and chlorine from a plant raw material was examined for the purpose of further reducing potassium and chlorine of solid biomass fuel.

Was developed result of the examination is a solid biomass fuel produced from plant-derived raw material oil palm, plant material derived from this oil palm is the ground state, and stirred in hot water at 80 ° C. to 100 ° C. Potassium and chlorine are eluted in the hot water by rinsing later, and the vegetable oil and animal fat that solidify at room temperature are melted in a state of further eluting the potassium and chlorine into pellets and having a temperature of 190 ° C to 200 ° C. It is a solid biomass fuel characterized in that it is fried with oil to increase the calorific value and shape retention of the pellets . The plant raw material derived from oil palm is angiosperms remaining after taking out seeds or fruits, and branches, leaves, trunks, roots which are not used or discarded after harvesting or cutting. For example, oil palm seed husks (PKS), empty fruit bunches (EFB), pulp fibers (PPF) and old oil palm trees (TRUNK), such as oil palm, remaining after squeezing palm oil are also included in plant materials.

  In the pulverized state, the plant raw material is agitated in hot water to elute potassium and chlorine into the hot water, and further rinsed with hot water eluting potassium and chlorine to remain. prevent. The plant material should be pulverized so that the maximum width is 10 mm or less, preferably 6 mm or less. The ground plant material has a large specific surface area and is easy to elute potassium and chlorine into hot water. Thus, when the plant raw material is pelletized, the potassium and chlorine in the solid biomass fuel are greatly reduced by removing water containing potassium and chlorine.

  The hot water is preferably 80 ° C to 100 ° C. The hot water stirring means may be based on circulation of the hot water itself, or may be mechanical stirring means. The rinsing of the plant material is a mode in which another water or hot water is injected while discharging hot water from which potassium and chlorine are eluted, or another plant material is taken out from the hot water from which potassium and chlorine are eluted. It is transferred to water or hot water, or plant raw materials are taken out from hot water from which potassium and chlorine are eluted and exposed to flowing water or hot water. If plant raw materials are put into hot water that circulates while separating potassium and chlorine, stirring and rinsing in hot water can be performed continuously and repeatedly.

  Plant raw materials are dehydrated when fried in oil with potassium and chlorine eluted. In the dehydration, water is discharged from the plant raw material together with the eluted potassium and chlorine, and oil is infiltrated into the voids containing the water. The pulverized plant material has a specific surface area that is easily transferred from the surface to the entire interior, and is dehydrated uniformly in a short time. Thus, the solid biomass fuel is further reduced in potassium and chlorine, and the calorific value is increased by the absorbed oil. Moreover, the plant raw material is good to be fried in oil in a state of being formed into pellets. A pellet is a granule formed by pressing and crushing a pulverized plant material into a certain outer shape. For example, when a cylindrical pellet is fried in oil, heat is uniformly transferred from the surface to the entire interior, and is dehydrated uniformly in a short time.

  When the plant raw material is fried with oil obtained by melting vegetable oil or animal fat that solidifies at room temperature, it becomes a solid biomass fuel containing oil that does not flow out by solidifying at room temperature. The normal temperature is 20 ° C. ± 15 ° C. (JIS Z 8703). Any vegetable oil or animal fat may be used as long as it solidifies in the normal temperature range. Furthermore, when the plant raw material is fried with hydrogenated vegetable oil or animal oil and fat, it becomes a solid biomass fuel containing the hydrogenated vegetable oil or animal fat in a solidified state at room temperature. In particular, since vegetable oils and fats have a low melting point except for palm oil, they are preferably hydrogenated and solidified at room temperature. Palm oil can also have a high melting point by hydrogenation.

  The solid biomass fuel of the present invention is a production method for producing a solid biomass fuel from a plant raw material, and includes a pulverization step for pulverizing the plant raw material, and rinsing the plant raw material that has undergone the pulverization step after stirring in hot water. Solid biomass fuel comprising a removal step for eluting potassium and chlorine into hot water, a forming step for pelletizing the plant raw material after the removal step, and a reforming step for frying the pellet after the forming step with oil It is manufactured by the manufacturing method.

  In the pulverization step, potassium and chlorine are easily eluted in hot water in the removal step, and pellets are easily formed in the forming step. In the removing step, potassium and chlorine are eluted from the pulverized plant raw material into hot water, and the plant raw material is rinsed to wash off the hot water from which potassium and chlorine have been eluted, thereby removing potassium and chlorine from the plant raw material. In the molding process, the pulverized plant material is pelletized to reduce volume and improve handling. In the reforming step, the pellets are hardened by dehydration by discharging moisture together with the eluted potassium and chlorine, and oil is soaked into the voids containing the moisture to obtain a solid biomass fuel having an increased calorific value.

  In the reforming step, the pellets that have undergone the molding step may be fried with oil obtained by melting vegetable oil or animal fat that solidifies at room temperature. This reduces the risk of oil flowing out of the solid biomass fuel that has returned to ambient temperature. Further, in the reforming step, the pellets that have undergone the molding step may be fried with oil obtained by melting hydrogenated vegetable oil or animal fat. Thereby, melting | fusing point of vegetable oil or animal fat is made high, and there is no fear that oil will flow out from solid biomass fuel. In particular, vegetable oils and fats other than palm oil are preferably hydrogenated. Palm oil can also have a high melting point when hydrogenated.

  The present invention can further reduce potassium and chlorine in the solid biomass fuel as compared with the case where the plant raw material is simply exposed to water or hot water to remove potassium and chlorine. In addition to eluting potassium and chlorine by stirring the pulverized plant raw material in hot water, the plant raw material is rinsed so that the hot water from which the potassium and chlorine are eluted adheres to the plant raw material. This is the effect of preventing the remaining. The water or hot water in which the plant material is rinsed is first mixed with hot water from which potassium and chlorine have been eluted, concentrated, and used as fertilizer (see Patent Document 1).

  The plant raw material is dehydrated when it is fried in oil in a state where potassium and chlorine are eluted. Water is discharged from the plant raw material together with the eluted potassium and chlorine, and the oil enters the voids containing the water. Thus, the solid biomass fuel is further reduced in potassium and chlorine, and the calorific value is increased by the absorbed oil. In addition, when the plant raw material is formed into pellets and fried in oil, the volume can be reduced to a solid biomass fuel as compared with the pulverized state. The pellets fried in oil have a high shape retaining property that retains the outer shape even when submerged, and enable outdoor storage exposed to rain, for example.

  When the plant raw material is fried with oil obtained by melting vegetable oil or animal fat that solidifies at room temperature, the risk of oil flowing out from the solid biomass fuel transported or stored at room temperature can be reduced. Further, the plant raw material is made available by using a vegetable oil or animal oil that normally melts at room temperature when fried with a hydrogenated vegetable oil or animal oil. In addition, hydrogenation increases the melting point of vegetable oil or animal fat that solidifies at room temperature, and makes it difficult for oil to flow out from the solid biomass fuel that is transported or stored even when the outside air temperature exceeds 40 ° C.

  The method for producing a solid biomass fuel according to the present invention makes it possible to produce pellets of solid biomass fuel with an increased calorific value by removing potassium and chlorine from plant raw materials. Potassium and chlorine are better removed than before by rinsing the pulverized plant material in hot water and rinsing, and further in the reforming process in which the plant material is fried in oil to increase the calorific value. Removed. Then, the oil is absorbed into the plant raw material by the reforming step, thereby making it possible to produce a solid biomass fuel that avoids high temperature corrosion of the boiler while increasing the calorific value.

  The reforming process in which the pellets are fried with oil obtained by melting vegetable oil or animal fat that is solidified at room temperature reduces the pulverized plant raw material, and enables production of pelletized solid biomass fuel that can be handled in the same manner as before. The reforming process in which pellets are fried with hydrogenated vegetable oil or animal oil / fat is increased by increasing the melting point of vegetable oil or animal fat, increasing the available vegetable oil or animal fat, The oil in which the fats and oils are melted is made difficult to flow out of the solid biomass fuel. When the vegetable oils and fats that can be used increase, the vegetable oils and fats that can be used in the present invention can be easily obtained, and the vegetable oils and fats that are available at different times can be switched and used. This makes it possible to produce a flexible and stable solid biomass fuel.

It is a block diagram showing an example of the production line of the solid biomass fuel to which this invention is applied.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The solid biomass fuel of the present invention is produced, for example, by a production line seen in FIG. The production line of this example produces solid biomass fuel from oil palm seed shell (PKS), empty fruit bunch (EFB), pulp fiber (PPF) and old oil palm tree (TRUNK) remaining after squeezing palm oil. It is an example. Oil palm seed husks, empty fruit bunches, pulp fibers and oil palm old trees may each be used alone as a plant material, or some or all of them may be used as a plant material. In addition, oil palm seed shells, empty fruit bunches, pulp fibers and old oil palm trees may be mixed with other plant materials.

  The production line of this example includes a crushing device 11 and a crushing device 12 that execute a crushing process, a cleaning device 21 that executes a removing process, a dehydrating device 31 that performs a forming process, a drying device 32, a quantitative supply device 33, and a manufacturing device. It comprises a granule device 34 and a flyer 41 for executing the reforming process. Each apparatus constituting each process is free as long as it can perform a pulverization process, a removal process, a molding process, or a modification process, and may have a configuration or combination other than this example. For example, the pulverization process may be configured only by the pulverization apparatus 12, or the molding process may be configured only by the granulation apparatus 34.

  In the pulverization step, the pulverized plant raw material 121 is obtained by the pulverizer 11 and the pulverizer 12. Oil palm seed shells (PKS), empty fruit bunches (EFB), and pulp fibers (PPF) may be directly pulverized by the pulverizer 12 without passing through the pulverizer 11. The old oil palm tree (TRUNK) is crushed by the crushing device 11 and then crushed by the crushing device 12. The crushed plant material is crushed with a maximum width of 50 mm or less as a guide, and is sequentially sent to the pulverizer 12 by a conventionally known conveyance means (conveyor or air conveyance). The pulverized plant raw material 121 is pulverized to a maximum width of 10 mm or less, preferably 6 mm or less, and is sequentially sent to the cleaning device 21 by a conventionally known conveyance means (conveyor or air conveyance).

  In the removing step, the plant raw material 211 from which potassium and chlorine have been removed is obtained by the cleaning device 21. The cleaning device 21 elutes potassium and chlorine from the plant raw material 121 into hot water by removing the ground plant raw material 121 into a container storing hot water at 80 ° C. to 100 ° C. and stirring it. To do. The hot water may be produced by another device outside the cleaning device 21 and transferred to the container at the start of the removal process, or the water stored in the container at the start of the removal process may be boiled by heating means. The heating means also has a function of heating hot water as needed so that the temperature of the hot water does not decrease while the pulverized plant raw material 121 is stirred in the hot water.

  The hot water may be stirred together with the pulverized plant raw material 121 in a state where the pulverized plant raw material 121 is charged. For this reason, the stirring means is not limited. In the cleaning device 21 of this example, three stirring rollers are arranged in the longitudinal direction of the container, and the plant raw material 121 pulverized with hot water is stirred together. Thus, the stirring means may be configured to use convection generated by boiling hot water in addition to a mechanical stirring roller, or may be configured to intermittently absorb and inject hot water. .

  After a predetermined treatment time, the cleaning device 21 drains hot water in which potassium and chlorine are dissolved from the container, supplies another hot water or water to the container, and supplies the plant raw material 211 from which potassium and chlorine have been removed. rinse. The plant raw material 211 from which potassium and chlorine have been removed may be rinsed with another hot water or water stored in a container, or may be rinsed in running water by continuing to supply and drain the other hot water or water. Good. The plant raw material 211 from which potassium and chlorine have been removed is separated from other hot water or water used for rinsing, and then sent to the dehydrating device 31 by a conventionally known conveying means (conveyor or air conveying).

  In the molding step, pellets 341 of plant raw material molded into a predetermined shape are obtained by the granulator 34. In the molding process of this example, it is difficult to pelletize plant raw materials that are oil palm seed husks, empty fruit bunches, pulp fibers and old oil palm trees immediately after the removal process. The removed plant raw material 211 is dehydrated, and after the moisture content of the plant raw material 211 is adjusted by the drying device 32, the plant raw material 211 is sent to the granulating device 34 by the quantitative supply device 33. The plant raw material 211 from which potassium and chlorine have been removed may be sent directly to the granulator 34 without intermediate treatment (dehydration treatment, drying treatment, quantitative supply) depending on the type.

  The plant raw material 211 from which potassium and chlorine have been removed is sent between the dehydrating device 31, the drying device 32, the quantitative supply device 33 and the granulating device 34 by a conventionally known conveying means (conveyor or air conveying). The granulator 34 forms the moisture-adjusted plant raw material 211 into plant raw material pellets 341 having a predetermined shape. The granulator 34 preferably uses a ring die from the viewpoint of molding a large amount of plant raw material 211. The pellet 341 formed by the granulating apparatus 34 using a ring die is usually cylindrical. The pellets 341 thus obtained are sequentially sent to the fryer 41 by a conventionally known conveying means (conveyor or air conveying).

  In the reforming step, pellets 411 that are deep-fried and modified by the fryer 41 are obtained. The flyer 41 of this example is stored and heated in an oil tank while moving the pellets 341 on a net conveyor so that the pellets 341 of plant raw materials sequentially sent from the granulator 34 are fried in oil. It is a structure to be immersed in the oil. The flyer 41, which is stored in an oil tank and submerged in heated oil while moving the pellets 341 of plant material on the net conveyor, has the advantage that the time to fry with oil can be adjusted by adjusting the moving speed of the net conveyor There is.

  The heated oil stored in the oil tank can be used as long as it can dehydrate the plant raw material pellets 341 by frying. From this point of view, the oil to be used may be, for example, mineral oil, but from the viewpoint of reducing or preventing outflow from the obtained pellet 411, oil obtained by melting vegetable oil or animal oil that solidifies at room temperature is preferable. The oil used in this example is used by heating palm oil that melts at 27 ° C to 35 ° C to 190 ° C to 200 ° C. Palm oil produces oil palm seed husks, empty fruit bunches, and pulp fibers, which are plant raw materials during the collection process, so that it can be procured at the same time as the plant raw materials and is a vegetable oil that solidifies at room temperature. preferable.

  When the plant material pellets 341 are fried in oil, the water containing potassium and chlorine is removed by dehydration and hardened, and the oil is infiltrated into the voids after the water is removed to reduce the amount of potassium and chlorine. Thus, the pellet 411 of solid biomass fuel with an increased calorific value is obtained. The pellets 411 of the solid biomass fuel are sequentially taken out from the fryer 41, stored indoors or outdoors, and shipped in a certain unit. The pellets 411 of solid biomass fuel fried with oil obtained by melting vegetable oil or animal oil solidified at normal temperature, for example, do not flow out even during cargo handling during rainfall. Moreover, since the solid biomass fuel pellet 411 does not lose its outer shape, it can be stored outdoors exposed to rainfall, for example.

  A solid biomass fuel (Example 1) was produced using an empty palm bunch (EFB) as a plant raw material and using a production line based on the above example. Oil palm empty fruit bunch is a plant material obtained when palm oil is collected. The prepared oil palm bunch is about 2 kg. First, empty fruit bunches were pulverized in the pulverization step so that most of the fiber length was 6 mm or less. In the removal process, all the crushed empty fruit bunches are poured into 40 L of hot water of about 100 ° C. and stirred for about 20 minutes, and then the hot water is drained, and then about 15 minutes with running water of about 15 ° C. Rinse.

  The empty fruit buns from which potassium and chlorine have been removed in this way were formed into cylindrical pellets having an outer diameter of 6 mm and a length of 20 mm to 25 mm in the molding process. Cylindrical pellets still contain moisture and are slightly soft. In the reforming step, the cylindrical pellets were deep-fried and dehydrated for about 20 minutes in a state where all of them were put into 40 L of palm oil at about 200 ° C. The obtained solid biomass fuel pellet (Example 1) has almost no moisture and is hardened.

  About Example 1, the low calorific value which is an important parameter | index as a solid biomass fuel was measured. The measurement results are shown in Table 1. The low calorific value of Example 1 was 5286 kcal / kg (calculated from the high calorific value according to JIS M8814. The high calorific value was measured in the pump calorific value system according to JIS M8814). Considering that the conventional solid biomass fuel made from oil palm empty fruit bunches (EFB) has a low calorific value of the latter half of 4000 kcal / kg at the highest, the solid biomass fuel of the present invention has a low calorific value. It can be said that it is extremely expensive.

Further, (measured by ICP emission spectrometry) of potassium remaining in the first embodiment 280 mg / kg, residual chlorine measuring instrument measurement limit (100 mg / kg) less than (JIS Z7302-6.10.1 and 11.2 combustion ion Measurement by chromatographic method). In the state of the crushed empty fruit bunches, the residual potassium was 5900 mg / kg and the residual chlorine was 1400 mg / kg. From this, it is considered that the solid biomass fuel of the present invention has an extremely small amount of residual potassium and chlorine, and is advantageous in that it does not easily cause high temperature corrosion during combustion in a boiler.

  Further, the ash content of Example 1 is 1.3% (based on the sewage test method, Part 5, Chapter 1, Section 7, weight method), and the moisture content of Example 1 is 1.0% (WB) (Sewage test method, Part 5, Part 1). Chapter 6 section, by weight method). In the state of the crushed empty fruit bunches, the ash content was 9.6% and the water content was 7.7% (W.B.). From this, it can be seen that the solid biomass fuel of the present invention requires less ash remaining after combustion, and the amount of heat generation due to the influence of moisture is extremely small.

  Solid biomass fuel was produced using a production line in accordance with the above example using oil palm old tree (TRUNK) as a plant raw material. The old oil palm tree is a plant material obtained when replanting the oil palm. The prepared oil palm oil is about 2kg. First, the old wood was crushed in the crushing step so that the maximum width was 50 mm or less, and then crushed so that the maximum width was 10 mm or less. In the removal process, all of the crushed old wood is poured into 40 L of hot water of about 100 ° C., stirred for about 20 minutes, and then the hot water is drained, and then rinsed with running water of about 15 ° C. for about 20 minutes. It is.

  In this way, the old tree from which potassium and chlorine had been removed was formed into cylindrical pellets having an outer diameter of 6 mm and a length of 20 mm to 25 mm. Cylindrical pellets still contain moisture and are slightly soft. In the reforming step, the cylindrical pellets were deep-fried and dehydrated for about 20 minutes in a state where all of them were put into 40 L of palm oil at about 200 ° C. The obtained solid biomass fuel pellets (Example 2) have almost no moisture and are hardened.

  About Example 2, the low calorific value which is an important index as solid biomass fuel was measured. The results are shown in Table 2. As a result, the lower calorific value of Example 2 was 4880 kcal / kg (calculated from the higher calorific value according to JIS M8814. The higher calorific value was measured with a pump calorific value system according to JIS M8814). Considering that the lower calorific value of pellet-shaped solid biomass fuel produced from wood is 4000 kcal / kg to 4200 kcal / kg, the solid biomass fuel of the present invention has a lower calorific value than the existing solid biomass fuel. It can be said that the amount is high enough.

Further, (measured by ICP emission spectrometry) of potassium remaining in the second embodiment 390 mg / kg, residual chlorine measuring instrument measurement limit (100 mg / kg) less than (JIS Z7302-6.10.1 and 11.2 combustion ion Measurement by chromatographic method). Furthermore, the ash content of Example 2 is 2.1% (based on the sewage test method, Part 5, Chapter 1, Section 7, weight method), and the moisture content of Example 2 is 0.5% (WB) (Sewage test method, Part 5, Part 1). Chapter 6 section, by weight method).

Compared to Example 2, in order to see the effect of the removal step and the modification step, the pellets of Comparative Example 1 without the removal step and the modification step and the pellets of Comparative Example 2 without the modification step are manufactured, respectively, and the lower heat generation. The amount, residual potassium and chlorine, ash and moisture were measured. The results are shown in Table 2. Comparative Example 1 does not have a removal process and a modification process, and moves from the pulverization process to the molding process to mold only the pellets. Comparative Example 2 has the same manufacturing conditions as Example 2 except that there is no reforming step.

Comparative Example 1 (pellet without removal process and modification process compared to Example 2) has a lower heating value of 4090 kcal / kg, residual potassium of 7700 mg / kg, residual chlorine of 4400 mg / kg, ash content of 3.0% And the water content was 12.1% (WB). In addition, Comparative Example 2 (pellets without a modification step compared to Example 2) has a lower calorific value of 4210 kcal / kg, residual potassium of 450 mg / kg, and residual chlorine of measurement limit (100 mg / kg) Less than 2.5 % ash and 10.5 % water (WB).

In Example 2, the lower heating value is higher than those of Comparative Example 1 and Comparative Example 2, and the residual potassium, residual chlorine, ash, and moisture are less than those of Comparative Example 1 and Comparative Example 2. From this, it is understood that the solid biomass fuel of the present invention is a good quality fuel. Example 2 shows that even if the lower calorific value does not reach that of Example 1, solid biomass fuel equivalent to conventional solid biomass fuel using empty fruit bunch (EFB) as a plant material can be produced from old oil palm trees. Prove that.

Here, when comparing the Comparative Example 1 and Comparative Example 2, lower calorific value than that of Comparative Example 1 of Comparative Example 2 was added to the removing step only pulverization step is slightly improved, potassium remaining and chlorine are greatly reduced I understand that. This confirms the usefulness of the removal step. In addition, when Example 2 and Comparative Example 2 are compared, Example 2 that has undergone the reforming process significantly reduces moisture while slightly reducing moisture. This infers that dehydration by the reforming process contributes to the reduction of the remaining potassium. From this, it can be said that the solid biomass fuel of the present invention provides the best effect when the removal step and the reforming step are combined.

11 Crusher
12 Crusher
121 Crushed plant material
21 Cleaning equipment
211 Plant material from which potassium and chlorine have been removed
31 Dehydrator
32 Drying equipment
33 Metering device
34 Granulator
341 Pellet of plant material
41 Flyer
411 Solid biomass fuel pellets

Claims (2)

Solid biomass fuel produced from oil palm derived plant material,
The plant material derived from the oil palm is pulverized and stirred in hot water at 80 ° C. to 100 ° C. and then rinsed to elute potassium and chlorine into the hot water, and further elute the potassium and chlorine. In a state of being pelletized, the solid is characterized in that it is fried in an oil of 190 ° C. to 200 ° C. in which vegetable oil or animal fat solidified at room temperature is melted to increase the heat generation amount and shape retention of the pellet. Biomass fuel. A production method for producing solid biomass fuel from oil palm derived plant material,
A pulverizing step of pulverizing the plant material,
A removal step of eluting potassium and chlorine into hot water by rinsing the plant raw material that has undergone the pulverization step after stirring in hot water at 80 ° C to 100 ° C ;
A molding step to pelletize the plant material after the removal step;
A method for producing a solid biomass fuel, comprising: a reforming step in which the pellets that have undergone the molding step are solidified at room temperature and fried with a 190 ° C to 200 ° C oil obtained by melting vegetable oils and animal fats .

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