Field of the Invention

The present invention relates to a device used to remove impurities from raw material and an ethanol preparation system and method. More particularly, the present invention relates to a device used to remove impurities from raw material in the course of conveyance of raw material, as well as an ethanol preparation system including the device and the method thereof.

Background of the Invention

On various occasions of industrial application, raw material often needs to be conveyed. For example, in a pulverized coal processing plant, the pulverized coal is often conveyed from one location to another by a belt conveyer; and in a grain processing plant, grain particles like corn as raw material are often conveyed by various kinds of conveyors to subsequent steps (crushing for example); for another example, in the cassava-to-ethanol system, a belt conveyer is often used to realize the conveyance of granular or blocky raw material cassava in order to carry out the subsequent steps, such as, crushing or sand removing.

However, on these application occasions, some impurities are inevitably mingled in the conveyed raw material, such as: fine dirt, large stone blocks, plastic cloth or woven bag shreds and remnants of plastic products. Moreover, before raw material enters processing and treatment steps, it can't be thoroughly cleaned, particularly in the case of a large amount of raw material.

The impurities mingled in the raw material fall into two main categories by density. The density of the impurities in one category is much higher than the density of raw material, for example: the dirt as impurity relative to the cassava as raw material; and the stone blocks as impurity relative to the coal blocks as raw material. These impurities may be separated by centrifugation or sedimentation method by making use of the density difference between the impurities and raw material. The impurities in another category are lighter materials, for example: the remnants of woven bags or plastic bags in cassava raw material. It is difficult to remove these impurities (particularly the strip/cotton-like light and soft impurities) from the raw material.

If the raw material mingled with such soft and light impurities (such as: remnants of woven bags or plastic bags) enters the subsequent treatment step, on the one hand, the impurities will probably be accumulated in the subsequent conveyance process and result in blockage after some time. The operators have to check and clear up the blocked location. This work is time and energy consuming and affects the normal operation of the whole production line; and on the other hand, if the impurities enter (for example, in the cassava-to-ethanol process) the subsequent step, such as: crushing, fermentation or enzymolysis, they will seriously affect normal chemical reactions, thereby resulting in decline of the quality of the obtained product. Therefore, these impurities should be removed from raw material as completely as possible.

However, the methods adopted in the prior art typically are to decrease the generation of these impurities to some extent, for example: maximally reduce the tearing of woven bags and prevent the remnants of woven bags from entering cassava raw material. So far, no device can initiatively remove these soft and light impurities during conveyance of raw material.

Therefore, how to effectively remove these impurities (band-like light impurities in particular) from the raw material being conveyed has become an urgent technical problem in this field.

Summary of the Invention

The object of the present invention is to provide a device that can remove impurities from the raw material, particularly applicable to the removal of band-like light impurities, such as: strip/cotton-like plastic cloth.

According to one aspect of the present invention, a device used to remove impurities from raw material is provided. The device comprises a conveying unit and an impurity removing unit. The conveying unit is used to convey the raw material along a conveying line. The impurity removing unit is in a location where the raw material in the conveying line must pass, and is used to remove the band-like light impurities from the raw material conveyed along the conveying line

According to another aspect of the present invention, an ethanol preparation system is provided. The system comprises the foregoing device used to remove impurities from the raw material; a crushing device used to crush the raw material coming from the conveying unit of the device used to remove impurities from raw material; a pulp making device used to make the crushed raw material into pulp; an enzymolysis device used to enzymatically decompose the pulp to obtain enzymolytic product; and a fermentation device used to ferment the enzymolytic product to obtain ethanol.

According to another aspect of the present invention, an ethanol preparation method is provided. The method includes: conveying raw material by the conveying unit of the foregoing device used to remove impurities from raw material; crushing the conveyed raw material; making the crushed raw material into pulp; enzymatically decomposing the pulp to obtain enzymolytic product; and fermenting the enzymolytic product to obtain ethanol.

As the device provided according to the present invention and used to remove impurities from raw material has an impurity removing unit installed in a location where the raw material in the conveying line must pass, the impurity removing unit may retain the impurities of the raw material containing for example, band-like soft and light impurities when the raw material is conveyed along the conveying line, thereby playing a role of removing impurities. This impurity removing unit is particularly applicable to soft and light impurities.

Further, the ethanol preparation system and method provided according to the present invention adopt the technical solution of the device provided by the present invention and used to remove impurities from raw material, so they can remove the band-like light impurities from the raw material that is used to prepare ethanol, to avoid pipeline blockage and the problems that affect industrial production.

Brief Description of the Drawings

FIG. 1 is a schematic of an embodiment of the device used to remove impurities from the raw material;

FIG. 2-FIG 5 are schematics of several embodiments of the impurity removing claw;

FIG. 6 is a perspective view of an alternative embodiment of the impurity removing claw;

FIG. 7 is a side view of the impurity removing claw shown in FIG. 6;

FIG. 8 is a perspective view of an alternative embodiment of the impurity removing claw;

FIG. 9 is a perspective view of a part of the conveying pipeline;

FIG. 10 is a sectional view of the conveying pipeline in FIG. 9;

FIG. 11 is a schematic of an ethanol preparation system according to the present invention. Detailed Description of the Embodiments

The embodiments of the present invention will now be described in detail by referring to the accompanying drawings.

The device according to the present invention and used to remove impurities from the raw material comprises a conveying unit and an impurity removing unit. The conveying unit is used to convey the raw material along a conveying line. The impurity removing unit is in a location where the raw material in the conveying line must pass, and is used to remove the band-like light impurities from the raw material conveyed along the conveying line.

Here, the conveying line refers to the line or route the raw material passes when it is conveyed by a conveying unit. For example, the raw material may be conveyed by a belt conveyer. In this case, the route the raw material passes on the conveyer belt of the belt conveyor is the conveying line of the raw material. As an impurity removing unit is installed in a location where the raw material in the conveying line must pass, when the raw material passes the impurity removing unit, the impurity removing unit will retain the impurities mingled in the raw material, thus realizing separation between the raw material and impurities and achieving the object of removing impurities. In other words, the device according to the present invention used to remove impurities from raw material can remove impurities from raw material while the raw material is being conveyed, thereby overcoming the foregoing defects of the prior art.

The conveying unit may have a plurality of forms. For example, as shown in FIG. 1, the conveying unit may comprise a belt conveyer 10. Although the belt conveyer 10 shown in FIG. 1 is horizontally disposed, the way of its disposition is not limited to this and it may be disposed obliquely. The impurity removing unit may have a plurality of forms, such as: various kinds of screens or electrostatic or magnetic impurity removing units. Preferably, to deal with strip/cotton-like or band-like light impurities, as shown in FIG. 1, the impurity removing unit comprises an impurity removing claw 20 under the location where the conveyer belt of the belt conveyer 10 outputs raw material.

Therefore, when the raw material conveyed by the conveyer belt of the belt conveyer 10 leaves the conveyer belt, the raw material will move downward or obliquely downward under the action of gravity. As the impurity removing claw 20 is disposed under the location where the conveyer belt outputs raw material, the raw material will certainly pass the impurity removing claw 20 and receive impurity removing treatment of the impurity removing claw 20. Consequently, the impurity removing claw 20 retains the impurities mingled in the raw material and allows the raw material to move on, thereby achieving the object of removing impurities.

According to an alternative optional form, the conveying unit may comprise a belt conveyer 10 and a conveying pipeline 40. The conveying pipeline 40 cooperates with the belt conveyer 10 to receive the raw material coming from the belt conveyer 10.

According to an embodiment of the present invention, the conveying pipeline 40 is even lower than the belt conveyer 10, or in other words, the conveying pipeline 40 is extended downward or obliquely downward from the location where the conveyer belt outputs raw material, so the raw material may be easily conveyed in the conveying pipeline 40 under gravity.

The conveying pipeline 40 as shown in FIG. 1 may be set as a suction-type elevator, i.e. the conveying pipeline 40 is extended upward or obliquely upward from the location where the conveyer belt outputs raw material. The suction-type elevator forms a high negative pressure in the conveying pipeline 40 through a high-power exhaust fan, so when the raw material passes the port of the conveying pipeline 40, it will be sucked into the conveying pipeline 40 and conveyed in the conveying pipeline 40. In this case, the impurities with high density in the raw material, like stone blocks, won't be sucked into the conveying pipeline 40 due to larger gravity. Therefore, this embodiment has the function of removing heavier impurities.

In order to remove the impurities from the raw material in the conveying pipeline 40, preferably, the impurity removing unit comprises an impurity removing claw 20. The impurity removing claw 20 is located inside the conveying pipeline 40, or under the location where the conveyer belt of the belt conveyer 10 outputs raw material, or inside the conveying pipeline 40 and under the location where the conveyer belt of the belt conveyer 10 outputs raw material, to achieve a better impurity removing effect. Therefore, when the raw material is conveyed in the conveying pipeline 40, naturally it will receive the action of the impurity removing claw in the conveying pipeline 40, thereby the impurities are removed. There may be one or a plurality of the foregoing impurity removing claws 20. The number and positions of the impurity removing claws 20 may be selected according to the specific application occasion.

The raw material mentioned here may be a plurality of materials, such as: blocky, flaky or granular cassava, sweet potato, potato and corn.

The impurity removing claw 20 will now be described in detail by referring to FIG. 2-FIG. 8.

As shown in FIG. 2-FIG 5, the impurity removing claw 20 comprises a rod- like base part 1 and a plurality of toothed parts 2 connected to the base part 1. The toothed parts 2 are arranged along the base part 1.

When the raw material mingled with soft and light impurities passes the impurity removing claw 20, the raw material will fully contact the toothed parts 2 of the impurity removing claw 20. As a result, the impurities are retained by the toothed parts 2 and the raw material passes the device. This process can remove impurities from raw material and realize the object of the present invention.

The base part 1 mainly plays a role of supporting so that the toothed parts 2 are mounted to it, but it may also play a combing role and retain part of the impurities when the impurities pass it.

In order to easily install the toothed parts 2 along the base part 1 , the base part 1 is rod- like and its cross sectional shape may be rectangle, square, circle or any appropriate shape, such as: a flat shape.

The toothed parts 2 are arranged along the base part 1, thereby the toothed parts 2 form a combing area where the toothed parts 2 interact with the raw material mingled with impurities. When the raw material mingled with impurities passes the combing area of the toothed parts 2, the toothed parts 2 will play a combing role like a comb, thereby retaining the impurities in the raw material and hanging the impurities on the toothed parts 2, to prevent the impurities from moving together with the raw material towards the subsequent step.

The toothed parts 2 have a plurality of forms, such as: in a shape of a round rod or grid, as long as the shape can realize the combing role of the toothed parts 2 and impurities can be removed.

In the device according to the present invention used to remove impurities, the base part 1 and the toothed parts 2 may be made from various kinds of appropriate materials, such as metal materials like steel, cast iron and stainless steel, or nonmetal materials like plastic and ceramic. The materials of the base part 1 and the toothed parts 2 may be selected based on the type of the raw material.

As shown in FIG. 2-FIG 5, the toothed parts 2 may be in a same plane. According to this embodiment, in the device used to remove impurities, the toothed parts 2 are all in a same plane. Therefore, the combing area where this device used to removing impurities interacts with raw material is the planar area where the toothed parts 2 are located.

In the device of this embodiment, when the raw material mingled with impurities passes the combing area of the toothed parts 2, the raw material will pass through the clearances of the toothed parts 2 and the toothed parts 2 will play a combing role to the raw material passing through them and retain the impurities in the raw material, thereby realizing separation between the raw material and the impurities and removing the impurities from the raw material.

In this embodiment, as the combing area where the device interacts with raw material is planar, it has low resistance to the raw material flowing through this area, the raw material may pass through the combing area of the toothed parts 2 at a high speed and the impurities in the raw material can be removed at the same time.

Further, as shown in FIG. 2-FIG 4, the toothed parts 2 may be extended in parallel from the base part 1 along the base part 1. As the toothed parts 2 are parallel with each other, the space between two adjacent toothed parts 2 is large and the distribution is even so as to facilitate high-speed passing of the raw material.

Further, the toothed parts 2 may also be disposed onto the base part 1 in different ways. As shown in FIG. 2, in this embodiment, a plurality of parallel toothed parts 2 are disposed on the base part 1 and on the same side of the base part 1 and form a shape similar to a comb.

In the form shown in FIG. 3, a plurality of parallel toothed parts 2 are distributed on each of the two opposite sides of the base part 1. Therefore, in comparison with the embodiment shown in FIG. 2, the toothed parts 2 in the embodiment shown in FIG. 3 have a larger active area, thereby having higher impurity removing ability.

Further, as shown in FIG. 4, through adjusting the mounting positions of the toothed parts 2 in the embodiment shown in FIG. 3, the spacing of the toothed parts 2 may be adjusted to adapt to the requirements of different active area. The sparser area is applicable to the raw material containing impurities with a larger volume, while the denser area is applicable to the raw material containing impurities with a smaller volume.

Further, as shown in FIG. 5, at least some of the toothed parts 2 may cross each other. In this embodiment, as the toothed parts 2 are not all parallel with each other and some of them cross each other, they may play a combing role in a direction oblique from the base part 1 to maximally retain the impurities in the raw material. In the embodiment shown in FIG. 5, the active area of the toothed parts 2 is larger than the active area in the embodiment shown in FIG. 2, so it has higher impurity removing ability.

According to a preferred embodiment of the present invention, as shown in FIG. 6 and FIG. 8, the toothed parts 2 are divided into a plurality of groups along the axial direction of the base part 1. These groups of toothed parts 2 are spaced out at an equal angle along the peripheral direction of the base part 1.

In the embodiment shown in FIG. 6 and FIG. 8, the toothed parts are not in a same plane and form a three-dimensional structure like a "spiked club" around the base part 1, therefore the combing area that can play a combing role is three-dimensional.

When the raw material mingled with impurities passes the three-dimensional toothed parts 2, the toothed parts 2 can remove the impurities in the raw material repeatedly, so they have even higher impurity removing ability.

In the embodiment shown in FIG. 6 and FIG. 8, the toothed parts 2 are divided into a plurality of groups along the longitudinal direction of the base part 1 (i.e. axial direction). For example, the toothed parts 2 may be divided into three groups in FIG. 7. However, the present invention is not limited to this and there may be 2, 3, 5, 6 groups and etc. Further, preferably, these groups of toothed parts 2 are spaced out at an equal angle along the peripheral direction of the base part 1. As a result, the toothed parts 2 are evenly distributed in the space around the base part 1 and form a three-dimensional combing area. Of course, these groups of toothed parts 2 may also be spaced out at unequal angles along the peripheral direction of the base part 1.

As shown in FIG. 6, the toothed parts 2 in any group are in a same plane. Under the circumstance shown in FIG. 6, the toothed parts 2 are divided into three groups along the axial direction of the base part 1, i.e. the first group 21, the second group 22 and the third group 23. The three groups of toothed parts are spaced out at an equal angle along the peripheral direction of the base part 1. That is to say, the included angle a of any two adjacent groups of toothed parts is 120°, as shown in FIG. 7. Further, the three tooth parts in the first group 21 are parallel with each other and are in a same plane, and the three tooth parts of the second group 22 and the third group 23 are arranged in the same way.

However, the present invention is not limited to this. For example, the toothed parts in each group may be not parallel with each other.

Further, as shown in FIG. 8, the toothed parts 2 in any group are helically arranged along the axial direction of the base part 1. That is to say, the difference of this embodiment between the embodiment shown in FIG. 6 and FIG. 7 is that the toothed parts in one group are not in a same plane and are helically arranged along the axial direction of the base part 1.

Specifically, as shown in FIG. 8, the preferred base part 1 is a cylinder and the three toothed parts in the first group 21, the second group 22 and the third group 23 are arranged on the base part 1 along three different helical lines. Preferably, in order to easily arrange these three groups of toothed parts 2, the helical radii of the three helical lines are all the radius of the base part 1, their axes are all the central axis of the cylinder of the base part 1, and they have the same lead and hand of helix and only they have different starting points. Further, the included angle a of the groups of toothed parts 21, 22 and 23 is same, i.e. 120°.

However, the embodiments of the present invention are not limited to this. The helical lines of the groups of toothed parts 2 may have different or same helical radius, cylinder central axis or lead.

Although the toothed parts are divided into three groups 21, 22 and 23 in FIG. 6 and FIG. 8, the present invention is not limited to this. In different embodiments, 2, 4, 5 or 6 groups of toothed parts may be arranged along the base part 1 and the included angle between two adjacent groups of toothed parts a is 180°, 90°, 72° or 60°. In the case that adjacent toothed parts are spaced out in unequal angles, the included angle between two adjacent groups of toothed parts a may be 20°~180°.

Preferably, the ends of the toothed parts 2 have hook structure. When the light and soft impurities receive action from the toothed parts 2, this hook structure may more reliably and sufficiently retain impurities to the toothed parts 2.

According to a preferred embodiment of the present invention, in order to facilitate installation in the conveying pipeline 40, the impurity removing unit also comprises at least one screen. The at least one screen is inside the conveying pipeline 40 and the plane where the screen is located is perpendicular to the longitudinal direction of the conveying pipeline 40. Therefore, when the raw material is conveyed in the conveying pipeline 40, the impurities mingled in the raw material may be removed through the screen.

There may be only one screen, but it is preferred to have a plurality of screens in order to give full play to their role in removing impurities. The screen may be disposed inside the conveying pipeline 40 by various methods. For example, the screen may be mounted to the inner surface of the side wall of the conveying pipeline 40 in a fixed manner (such as: welding , Snap-fit or screw fastener).

However, in order to clear the impurities on the screen in time and maintain smooth passage of the conveying pipeline 40, preferably, as shown in FIG. 9 and FIG. 10, at least one slot 44 is opened on the side wall of the conveying pipeline 40 and the at least one screen is inserted into the at least one slot 44.

The screen is inserted into the slot 44 and enters the conveying pipeline 40 to comb the impurities that pass the conveying pipeline 40 so as to remove impurities. Preferably, the plane where the screen is located is perpendicular to the longitudinal direction of the conveying pipeline 40, thereby the passing raw material can be fully combed.

The screen in the slot 44 may be supported by various methods. For example, a heave 45 (as shown in FIG. 10) may be disposed inside the conveying pipeline 40 or the wall of the conveying pipeline 40 at the slot 44 is directly used as a support.

During use, the screen is put into the conveying pipeline 40 (i.e. inserting the screen into the slot 44). When the impurities on the screen need to be cleared, the screen may be drawn out from the slot 44 and the impurities on the screen are removed and then the screen is inserted back into the slot 44 for continued use.

The device provided by the present invention and used to remove impurities from raw material has been described in details above. The use method or process of the device will be described below.

First of all, the raw material is conveyed through a belt conveyer as a conveying unit and output by the belt conveyer in the output location of the conveyer belt. When the raw material passes an impurity removing claw 20, the raw material will receive the combing action of the impurity removing claw 20 and consequently, the impurities mingled in the raw material will be retained, the normal raw material will pass and the raw material and the impurities will be separated.

When the raw material subsequently passes a conveying pipeline 40, at least one screen disposed inside the conveying pipeline 40 can further remove the impurities in the raw material. The raw material without impurities may be conveniently conveyed to the subsequent treatment device to go through the subsequent steps, for example: as shown in FIG. 1, it may be conveyed into a crusher 50 to be crushed.

In the process of using the conveying pipeline 40, the size and shape of sieve meshes of the screen may be selected based on the actual raw material and the form of the impurities. For example, if the raw material and the impurities are small, the screen with small meshes will be preferred.

Preferably, in order to make full use of the impurity removing role of the impurity removing claw 20 and the screen, the impurity removing claw 20 is in a location first contacting the raw material inside the conveying pipeline 40 and the screen is in a location later contacting the raw material inside the conveying pipeline 40. Therefore, in the process when the raw material passes the conveying pipeline 40, it contacts the impurity removing claw 20 at first to remove larger impurities and then contacts the screen to remove smaller impurities so as to obtain purer raw material.

The device provided by the present invention and used to remove impurities from raw material is not only applicable to remove impurities in granular raw material (such as: corn kernels or cassava granules) but also applicable to remove the impurities mingled in fluid. For example, it may remove the weed, plastic bags and other impurities in river water and may also be used to remove the textile fabrics (such as: woven fabric and spun yarn) in the air.

Further, the present invention also provides an ethanol preparation system that is equipped with the foregoing device used to remove impurities from the raw material, as well as an ethanol preparation method. The ethanol preparation system and method provided by the present invention will be described below.

As shown in FIG. 11, the ethanol preparation system provided by the present invention comprises the foregoing device used to remove impurities from the raw material; a crushing device 50 used to crush the raw material coming from the conveying unit of the device used to remove impurities from raw material; a pulp making device 100 used to make the crushed raw material into pulp; an enzymolysis device 400 used to enzymatically decompose the pulp to obtain enzymo lytic product; and a fermentation device 500 used to ferment the enzymo lytic product to obtain ethanol.

When the ethanol preparation system operates, the conveying unit of the foregoing device used to remove impurities from raw material will convey the pretreated (such as: cleaned, peeled and pre-crushed) raw material, such as: potato crop, to the crushing device 50 at first; then the crushing device 50 will crush the raw material into finer powdery raw material; then the crushed raw material will be conveyed to the pulp making device 100, and water will be added into the pulp making device 100 to mix with the crushed raw material and make pulp; then the pulp will be conveyed to the enzymolysis device 400 and amylase may be used to realize pulp enzymolysis and thereby obtain enzymolytic product; and finally yeast may be used to ferment the enzymolytic product in the fermentation device 500 and obtain ethanol in the end.

In order to facilitate the conveyance of raw material, the conveying unit is not limited to the form shown in FIG. 1. As shown in FIG. 11 , preferably, the conveying unit may also comprise a first conveying unit 80 (such as: scraper conveying unit), used to convey raw material from a warehouse to a needed location, for example, from an underground warehouse to a higher location; a distribution bin 70, used to receive the raw material conveyed from the first conveying unit 80 and supply the raw material to the subsequent vibrating grading screen 60 at a uniform speed; a vibrating grading screen 60, used to grade the raw material granules by means of vibration and allow the raw material granules that can pass the sieve meshes to enter the subsequent hopper 30, while the raw material granules that can't pass the sieve meshes will be treated separately, for example, pre-crushed again to a size that can pass the vibrating grading screen 60; and a hopper 30, used to store the raw material coming from the vibrating grading screen 60 and supply the raw material to the belt conveyer 10 (such as: a belt conveying unit). In the end, the raw material is conveyed to the crushing device 50. In the crushing device 50, the raw material is crushed to obtain the desired powdery raw material. The foregoing impurity removing unit may also be arranged in an appropriate location in the conveying line of the conveying unit as shown in FIG. 11.

In the ethanol preparation system provided by the present invention, the crushing device 50, the pulp making device 100, the enzymolysis device 400 and the fermentation device 500 may use various kinds of existing crushing devices, pulp making devices, enzymolysis devices and fermentation devices, respectively and adopt conventional crushing technologies, pulp making technologies, enzymolysis technologies and fermentation technologies to obtain ethanol in the end.

For example, with regard to the crushing device 50, the crushing device 50 may be a roll crusher, a hammer crusher, a jaw crusher or whatever as long as it may produce powdery raw material with acceptable grain size.

With regard to the enzymolysis device 400, during enzymolysis, zymogenic microorganisms and/or enzymes may be added into the crushed raw material and the temperature conducive to enzymolysis is maintained. The zymogenic microorganisms are the zymogenic microorganisms that can secrete amylase. The enzymes include amylase. The enzymolysis conditions are known to those skilled in the art.

With regard to the fermentation device 300, the fermentation device 300 is used to ferment the enzymolytic product. The fermentation may be completed by a method commonly used in the art, for example, adding yeast into the enzymolytic product and maintaining a temperature suitable for growth of the yeast. The yeast used for fermentation in the present invention may be commercial yeast solid preparation (such as: dry yeast powder) or yeast strain. The fermentation temperature may be any temperature suitable for growth of yeast, the preferred temperature is 30-36 ^° C and the more preferred is 30-33 ^° C . The pH value is 4-6 and the preferred is 4-4.5. The fermentation time may be 55-70h and the preferred is 60-70h. After fermentation of the enzymolytic product, fermentation product: ethanol may be obtained. According to the requirements of different industrial products (for example, the ethanol purity of fuel alcohol shall be above 99%), ethanol may be extracted by different methods, such as: distillation, concentration or dehydration.

Relative to the conventional ethanol preparation systems, the main improvement of the ethanol preparation system provided by the present invention is the introduction of the foregoing device used to remove impurities from the raw material. The device has an impurity removing unit. As described above, the impurity removing unit is in a location where the raw material in the conveying line must pass, and is used to remove the band-like light impurities from the raw material conveyed along the conveying line. Therefore, when the raw material is conveyed in the conveying line, the impurity removing unit will remove the impurities mingled in the raw material and avoid the entry of the impurities into the subsequent crushing device 50 as well as the follow-up pulp making device 100, enzymolysis device 400 and fermentation device 500, thereby overcoming the defect that the conventional ethanol preparation systems cannot effectively remove impurities.

The ethanol preparation method provided by the present invention includes: conveying the raw material by the conveying unit of the foregoing device used to remove impurities from raw material; crushing the conveyed raw material; making the crushed raw material into pulp; enzymatically decomposing the pulp to obtain enzymolytic product; and fermenting the enzymolytic product to obtain ethanol. The ethanol preparation method may be realized through the foregoing ethanol preparation system.

Above is the description of the device provided by the present invention and used to remove impurities, the ethanol preparation system including the device as well as the ethanol preparation method that makes use of this system. Although the present invention is disclosed through foregoing embodiments, the foregoing embodiments are not intended to limit the present invention. Anybody skilled in the technical field to which the present invention pertains may make various changes and modifications to the embodiments without departing from the spirit and scope of the present invention. Therefore, the scope defined by the accompanying claims shall be the protection scope of the present invention. For example, the foregoing device used to remove impurities is not limited to ethanol preparation field.