JP2007302462A - Belt conveyor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce volume and weight of excavated sediment and dredged sediment with high water content during conveyance. <P>SOLUTION: This belt conveyor 1 is constituted by hanging an endless belt 4 around a head pulley 2 disposed on the nose side and a tail pulley 3 disposed on the tail end side, and as shown in a sectional drawing, a belt 4 is formed by covering the conveying surface of a belt body 5 with a water absorbing/draining layer 6 formed of a temperature-sensitive water absorbing/draining water-retaining agent. Further, the belt conveyor 1 is constituted to form high temperature environment on the tail end side by providing a heater 8 serving as a heating means near the tail pulley 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a belt conveyor that conveys a conveying material having a high water content.

  In the mud pressure shield method, excavated earth and sand taken into the chamber of the shield machine is carried to the ground by a mud pump, a screw conveyor, a belt conveyor, etc., and stored in an earth and sand pit.

  Here, the mud pressure shield has a high moisture content of the excavated earth and sand because of the stability of the face by the mud pressure, so it is handled as industrial waste and the disposal cost is high. In addition, since a large amount of water is contained in the gaps between the soil particles, the weight per unit volume is large and the transportation cost is high. Furthermore, because of tunnel excavation, the amount of excavated sediment is enormous.

  For this reason, attempts have been made to reduce the volume and weight of excavated soil.

Japanese Patent Laid-Open No. 7-291419

  Here, if the excavated sediment is dried by a method such as sun drying, the moisture content will decrease and it can be used as general residual soil, but securing a vast site for sun drying in urban areas is not possible. Not realistic. In addition, if the water content ratio is reduced and the strength is improved by adding cement-based materials such as lime, it can be reused as construction materials. The material cost and the work cost for the addition become high, and it is difficult to apply in terms of economy, coupled with securing the processing site. Moreover, since the pH increases due to the addition of cement-based materials, disposal as general residual soil may be difficult.

  Thus, all the conventional methods for reducing the volume and weight of excavated sediment generated in the mud pressure shield method have room for improvement, and new technical development has been desired. In addition, the handling of other excavated sediments and dredged soils with a high water content ratio had the same problems as the mud pressure shield.

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a belt conveyor capable of reducing the volume and weight of excavated sediment and dredged soil having a high water content ratio during conveyance.

  In order to achieve the above object, a belt conveyor according to the present invention has an endless belt hung on a head pulley disposed on the nose side and a tail pulley disposed on the tail end side as described in claim 1. In the belt conveyor configured, the belt is configured by covering the transport surface of the belt main body with a water absorption / drainage layer made of a temperature-sensitive water absorption / retention water retention agent.

  In addition, the belt conveyor according to the present invention is a belt conveyor configured by applying an endless belt to a head pulley arranged on the nose side and a tail pulley arranged on the tail end side, as described in claim 2. The belt is constructed by covering the transport surface of the belt main body with a water-absorbing drainage layer in which a water-permeable material is used as a base material and a temperature-sensitive water-absorbing and water-retaining agent is mixed in the base material.

  In addition, the belt conveyor according to the present invention is a belt conveyor configured by applying an endless belt to a head pulley disposed on the nose side and a tail pulley disposed on the tail end side, as described in claim 3. In this case, the belt is constituted by a water-absorbing / draining belt obtained by mixing a water-permeable rubber with a temperature-sensitive water-absorbing water retaining agent.

  Further, as described in claim 4, the belt conveyor according to the present invention is a belt conveyor configured by hanging an endless belt between a head pulley disposed on the nose side and a tail pulley disposed on the tail end side. A water-absorbing and draining belt formed by mixing a temperature-sensitive water-absorbing and water-retaining agent into an impermeable rubber and forming at least a portion of the temperature-sensitive water-absorbing and water-retaining agent to be exposed on the conveying surface. The belt is configured as described above.

  Moreover, the belt conveyor which concerns on this invention is provided with the cooling means which cools this temperature-sensitive water absorption / drainage water retention agent when the said temperature-sensitive water absorption / drainage water retention agent exists in a waste_water | drain state.

  The belt conveyor according to the present invention comprises heating means for heating the temperature-sensitive water-absorbing and water-retaining agent when the temperature-sensitive water-absorbing and water-retaining agent is in a water-absorbing state.

  The belt conveyor according to the present invention uses excavated earth or dredged earth and sand as a conveying material.

  In the belt conveyor according to the present invention, the belt is formed by covering the conveyance surface of the belt body with a water-absorbing / draining layer made of a temperature-sensitive water-absorbing water-retaining agent, and a water-permeable material is used as a base material. A belt is formed by covering a belt main body with a water absorption / drainage layer mixed with a drainage water retention agent, and the belt is a water absorption / drainage belt formed by mixing a temperature-sensitive water absorption / drainage water retention agent with a permeable rubber. Or a water-absorbing and draining water formed by mixing a temperature-sensitive water-absorbing and water-retaining agent into the water-impermeable rubber, and at least a part of the temperature-sensitive water-absorbing and water-retaining agent is exposed on the conveying surface. The said belt is comprised with the property belt.

  The temperature-sensitive water-absorbing and water-retaining agent is a water-retaining agent having a function of absorbing and holding water below the temperature-sensitive point and discharging water when exceeding the temperature-sensitive point.

  The temperature-sensitive water-absorbing and water-retaining agent is configured as described above, and a high-temperature environment exceeding the temperature-sensitive point is formed in a predetermined section excluding the conveyance section where the conveyance material is placed on the belt, and the high-temperature environment is A low heat environment below the temperature sensing point is formed in all sections except the section to be formed.

  If it does in this way, in the area where the low heat environment is formed, the temperature-sensitive water-absorbing water retention agent can absorb or hold the moisture contained in the transport material, or the temperature-sensitive water-absorption water retention agent can absorb water. Maintained in a state. On the other hand, in the section where the high heat environment is formed, the moisture retained in the temperature-sensitive water-absorbing water retaining agent is discharged from the temperature-sensitive water-absorbing water retaining agent.

  In other words, the temperature-sensitive water-absorbing and water-retaining agent absorbs moisture contained in the conveying material in a low heat environment, and plays a role of discharging the moisture in a high heat environment while maintaining this. Thus, the conveying material is dehydrated from the conveying material in a form absorbed by the temperature-sensitive water-absorbing water retaining agent in a low heat environment, and the water content ratio is lowered.

  In addition, about the water discharged | emitted from the temperature sensitive water-absorbing water retention agent, water collection means, such as a pit, may be provided as needed, and it collect | recovers suitably.

  As the temperature-sensitive water-absorbing and water-retaining agent, for example, a product marketed by Kojin Co., Ltd. under the trade name “Thermogel” can be used. These “thermogels” are “a new material with a new function in the water-absorbing polymer”, “temperature-sensitive water-absorbing and draining resin that automatically drains the absorbed water when the set temperature is reached” and “temperature-sensitive point” Can be arbitrarily set according to the application between 15 ° C and 60 ° C, and there are "20, 25, 30, 35, 40 ° C as standard grades". "The thermosensitive absorption and drainage characteristics of thermogel are reversible, and the absorption and drainage characteristics do not change even if the absorption and drainage is repeated 10,000 times or more" (http: // www. (quoted from kohjin.co.jp/newbiz/projectgreen/thermogel.html)

  As described above, a section in which a high heat environment is formed is a section in which the temperature-sensitive water-absorbing and water-retaining water retaining agent is maintained in a temperature environment exceeding its temperature-sensitive point, and a section in which a low-heat environment is formed is a temperature-sensitive water absorption and drainage. The temperature-sensitive water-retaining agent is maintained in a temperature environment below the temperature-sensitive point, and the temperature-sensitive water-absorbing water-retaining agent contained in the belt circulates between the head pulley and tail pulley together with the belt. In a temperature environment.

  Note that the low heat environment and the high heat environment do not only indicate a case where it is formed by an active temperature operation using a cooling means such as a cooler or a heating means such as a heater, but also includes a passive temperature environment caused by outside air. It is a concept to do.

  Here, when the cooling means is provided, it is installed so that the temperature-sensitive water-absorbing and water-retaining agent can be cooled when the temperature-sensitive water-absorbing and water-retaining agent is in a drained state. Similarly, when a heating means is provided, the temperature-sensitive water-absorbing water retaining agent is installed so that it can be heated when the temperature-sensitive water-absorbing water retaining agent is in a water-absorbing state.

  The base material which is a water-permeable material can be composed of a porous material such as a sponge.

  The water-permeable rubber is formed by foaming a rubber material or a plastic material, and it is desirable to increase the content ratio of open cells rather than closed cells in order to increase water permeability.

  The water-impermeable rubber is formed of a commonly used general rubber material, and in order to form at least a part of the temperature-sensitive water-absorbing and water-retaining agent to be exposed on the conveying surface, for example, Add and mix a temperature-sensitive water-absorbing and water-retaining agent into a general rubber material, cure and form the temperature-sensitive water-and-drainage water-retaining agent as uniformly as possible, and then polish the surface that will be the conveying surface. do it.

  In addition, the belt conveyor according to the present invention is applicable to all conveying materials for which the water content ratio is desired to be reduced during conveyance, regardless of the field, excavation earth and sand generated during mud pressure shield construction, dredging work, etc. When dredged sand generated in the above is transported or used, it becomes possible to efficiently reduce the water content ratio of excavated sand and dredged sand generated in large quantities.

  Embodiments of a belt conveyor according to the present invention will be described below with reference to the accompanying drawings. Note that components that are substantially the same as those of the prior art are assigned the same reference numerals, and descriptions thereof are omitted.

  FIG. 1 is a view showing a belt conveyor according to the present embodiment. As can be seen in the figure, the belt conveyor 1 according to the present embodiment is configured by a belt 4 having an endless shape hung on a head pulley 2 disposed on the nose side and a tail pulley 3 disposed on the tail end side. However, as can be clearly seen in the cross-sectional view, the belt 4 is configured by covering the conveyance surface of the belt body 5 with a water absorption / drainage layer 6 made of a temperature-sensitive water absorption / drainage water retention agent.

  A temperature-sensitive water-absorbing and water-retaining agent is a water-retaining agent that absorbs and retains water below the temperature-sensitive point, and discharges water when the temperature-sensitive point is exceeded. You can use what is marketed by Kojin Co., Ltd. by name.

  Here, the water-absorbing / draining layer 6 made of a temperature-sensitive water-absorbing and water-retaining agent is covered with a belt body 5 and covered with a water-permeable sheet 7 made of a mesh sheet or the like. The edge is fixed to each side edge portion of the belt main body 5 by adhesion or the like, and with this configuration, peeling from the belt main body 5 can be prevented.

  The water-permeable sheet 7 can be comprised, for example with a nonwoven fabric.

  The belt conveyor 1 according to the present embodiment includes a heater 8 as a heating unit so that the belt 4 receives radiant heat in the vicinity of the tail pulley 3, more specifically, in the vicinity of the tail end on the return side after turning around the tail pulley 3. Is provided.

  In order to convey a conveyance material having a high water content ratio using the belt conveyor 1 according to the present embodiment, first, as shown in FIG. 2 (a), a conveyance material 11 having a high water content ratio is placed on the belt 4 on the nose side. Placed on.

  The transport material 11 can be any transport material as long as it is intended to dehydrate and remove moisture, but excavated sediment generated during mud pressure shield construction and dredged sediment generated during dredging work not only have a high water content ratio. Since it occurs in large quantities, if the belt conveyor 1 that can also remove moisture while also carrying is used, it is possible to efficiently remove and carry moisture.

  Here, assuming that the outside air temperature is 10 ° C., the temperature sensing point of the temperature-sensitive water-absorbing water retaining agent is set to 20 ° C., for example, and the high-temperature environment formed by the heater 8 is 30 °. Set to C.

  In this way, when the temperature sensitive point is 20 ° C., the temperature environment received by the temperature-sensitive water-absorbing and water-retaining agent of the belt 4 is as shown in FIG. From the point B to the point A, the temperature is over 20 ° C. which is a temperature sensitive point due to the influence of the heater 8, and this section becomes a high heat section. Further, the heating section by the heater 8 is included in the high heat section B to A and is a section from the B point to the C point. On the other hand, the point A to the point B is affected by the outside air temperature and becomes a temperature sensitive point of 20 ° C. or less, and this section becomes a low heat section. In addition, the conveyance area in which the conveyance material 11 is conveyed becomes ab.

  In such a temperature environment, while the conveying material 11 is continuously placed on the belt 4, a motor (not shown) of the belt conveyor 1 is driven to convey the conveying material 11 in the belt circulation direction indicated by the arrow in the figure. . At this time, since the sections A to B including the nose are low heat sections as described above, the moisture exuded from the transport material 11 overlaps the low heat sections A to B and the transport sections a to b. Water is absorbed by the temperature-sensitive water-absorbing and water-retaining agent constituting the water-absorbing and draining layer 6 in the sections a and b, and the absorbed water is held in the temperature-sensitive water-absorbing and water-retaining agent in the sections b and B.

  That is, the moisture contained in the transport material 11 is absorbed by the temperature-sensitive water-absorbing water retaining agent in the transport sections a and b, and water absorption using the transport distance (transport time) becomes possible.

  On the other hand, the transport material 11 having a reduced moisture content flows to the next processing step on the tail end side.

  Next, the moisture held in the temperature-sensitive water-absorbing water retaining agent in the sections b to B is sensed in the high heat sections B to A including the sections B to C heated by the heater 8 after the belt 4 rotates around the tail pulley 3. Drained from hot water-absorbing water retention agent.

  Next, since the temperature environment changes from the high heat zone to the low heat zone from the point A, the temperature-sensitive water-absorbing and water-retaining agent returns to a water-absorbable state.

  As described above, according to the belt conveyor 1 according to the present embodiment, the moisture in the transport material 11 placed at the nose is absorbed by the temperature sensitive material that constitutes the water absorption / drainage layer 6 in the transport sections a and b. Unless the water-absorbing function of the water-absorbing water-retaining agent is saturated and the water-absorbing function of the temperature-sensitive water-absorbing water-retaining agent is saturated, dehydration proceeds according to the conveying distance, and the moisture content of the conveying material 11 decreases. On the other hand, in the high heat zone B to A, since it is a high heat environment higher than the temperature sensing point, the water retained in the temperature sensitive water absorbing / draining water retaining agent is quickly drained from the temperature sensitive water absorbing / draining water retaining agent. The

  Thus, using the water absorption and drainage function of the temperature-sensitive water-absorbing water retaining agent that depends on the temperature difference, the water content of the transport material 11 is reduced to reduce the volume and weight, and the transport material 11 has a reduced water content. Can be reused as general residual soil.

  In the present embodiment, the belt 4 is configured by covering the conveyance surface of the belt body 5 with the water absorption / drainage layer 6 made of a temperature-sensitive water absorption / retention water retaining agent, but instead of this, as shown in FIG. Alternatively, a belt 4 'may be employed in which a base material 5 is coated with a water-absorbing / draining layer 6' formed by mixing a temperature-sensitive water-absorbing water retaining agent into the base material. .

  As the water permeable material, for example, a porous material such as a sponge may be used.

  Further, the belt may be constituted by a water-absorbing / water-absorbing belt formed by mixing a water-permeable rubber with a temperature-sensitive water-absorbing / water-retaining water retaining agent. As shown in FIG. The water retaining agent 43 may be mixed, and the belt 41 may be configured by a water absorbing / draining belt formed so that at least a part of the temperature sensitive water absorbing / draining water retaining agent is exposed to the conveying surface 44.

  Further, in the present embodiment, the belt main body 5 is covered with the water absorption / drainage layer 6, and the water permeable sheet 7 made of a mesh sheet or the like is covered thereon, and both edges of the water permeable sheet are adhered to the belt main body 5 by adhesion or the like. Although fixed to each side edge portion, the water-permeable sheet 7 may be omitted if there is no concern that the water absorption / drainage layer 6 is peeled off from the belt body 5.

  Further, in this embodiment, the heater 8 is provided as a heating means so that the belt 4 receives radiant heat at a position near the tail end on the return side after turning around the tail pulley 3, but this is shown in FIG. As described above, a cooler 51 as a cooling means may be provided in the vicinity of the head pulley 2.

  In such a configuration, it is assumed that the outside air temperature is 30 ° C., the temperature sensing point of the temperature-sensitive water-absorbing water retaining agent is set to 20 ° C., and the cooling temperature by the cooler 51 is set to 10 ° C. Set to.

  In this way, when the temperature sensitive point of 20 ° C. is used as a reference, the temperature environment received by the temperature-sensitive water-absorbing and water-retaining agent of the belt 4 is as shown in the figure, and from the point A along the circulation direction of the belt 4. Up to point B, the temperature is less than 20 ° C. due to the influence of the cooler 51, and this section becomes a low heat section. Further, the cooling section by the cooler 51 is included in the low heat sections A to B, and is a section from the point A to the point D. On the other hand, from point B to point A is affected by the outside air temperature and exceeds the temperature sensing point of 20 ° C., and this section becomes a high heat section.

  In such a temperature environment, while the conveying material 11 is continuously placed on the belt 4, a motor (not shown) of the belt conveyor 1 is driven to convey the conveying material 11 in the belt circulation direction indicated by the arrow in the figure. . At this time, since the sections A to B are the low heat sections as described above, the moisture exuded from the transport material 11 is the sections a to b where the low heat sections A to B and the transport sections a to b overlap. The water absorption is performed by the temperature-sensitive water-absorbing and water-retaining agent constituting the water-absorbing and draining layer 6, and the absorbed water is retained by the temperature-sensitive water-absorbing and water-retaining agent in the sections b to B.

  That is, the moisture contained in the transport material 11 is absorbed by the temperature-sensitive water-absorbing water retaining agent in the transport sections a and b, and water absorption using the transport distance (transport time) becomes possible.

  On the other hand, the transport material 11 having a reduced moisture content flows to the next processing step on the tail end side.

  Next, the moisture retained in the temperature-sensitive water-absorbing and water-retaining agent in the sections b to B is drained from the temperature-sensitive water-absorbing and water-retaining agent in the high-heat sections B to A after the belt 4 rotates around the tail pulley 3. .

  Next, since the temperature environment changes from the high heat zone to the low heat zone from the point A, the temperature-sensitive water-absorbing and water-retaining agent returns to a water-absorbable state.

  Incidentally, it can be said that the temperature environment of the present embodiment is a setting suitable for the winter season, and the temperature environment of the modified example is a setting suitable for the summer season.

  Here, it is possible to set the temperature sensitive point of the temperature-sensitive water-absorbing water retaining agent to 15 ° C., for example, the low temperature environment by the cooler 51 to 10 ° C., and the high heat environment by the heater 8 to 20 ° C. Even when the heater 8 and the cooler 51 are used in combination, there is no change in that a low temperature environment and a high temperature environment based on the temperature sensing point are formed.

  On the other hand, the heater 8 as the heating means and the cooler 51 as the cooling means are not essential. For example, in dredging work, the fact that mud that has just been dredged is close to the temperature of the bottom of the water, for example, 10 ° C. in the conveyance section. While considering the low heat environment, the return side may be considered to be a high heat environment of, for example, 20 ° C., and the temperature sensing point of the temperature-sensitive water-absorbing water retaining agent may be set to, for example, 15 ° C.

  In such an example, mud that has just been dredged is the cooling means. In addition, when it is difficult to form a low heat environment only with dredged mud, dry ice may be added as a cooling means. In this configuration, when the dredged mud is placed on the belt conveyor according to the present invention, the dry ice is preferably placed and placed so that the dry ice is sandwiched between the dredged mud and the belt.

  FIG. 6 shows the relative temperature relationship between the set temperature Tmin in the low heat environment, the set temperature Tmax in the high heat environment, the temperature sensing point T0, and the outside air temperature T. The transition from (a) to (e) is shown. It shows how the outside air temperature is relatively rising as you go. As can be seen from these figures, in cases (a) and (b), since the outside air temperature is relatively low, the cooling means is not necessary, but in case (a), the burden on the heating means becomes considerably large. In cases (d) and (e), since the outside air temperature is relatively high, no heating means is required, but in case (e), the burden on the cooling means is considerably increased, and cases (a) and (e) Neither of them has good thermal efficiency.

  On the other hand, in case (c), since the outside air temperature is close to the temperature sensing point T0, both the heating means and the cooling means are required, but the thermal efficiency is not bad.

  If necessary, it is desirable to appropriately select three cases (b) to (d) while taking into account the initial cost and running cost.

  As can be seen from the above description, in carrying out the present invention, in the case where the outside air temperature is constant at all points along the belt circulation path, the heating energy including the case of using the heat energy of the conveying material itself is used. It is necessary to use in combination with at least one of the means and the cooling means.

  However, this is not the case when the outside air temperature differs in the section along the belt circulation path.

  Specifically, in mud pressure shield construction, the outside air temperature differs between the nose side and the tail end side due to the long conveyance section, and the outside air temperature is 10 ° C due to the influence of underground temperature on the nose side. On the tail end side, when the outside air temperature becomes 30 ° C due to the influence of the ground temperature through the shaft, if the temperature sensing point of the temperature-sensitive water-absorbing water retaining agent is set to 20 ° C, the heating means and Even if both of the cooling means are omitted, dehydration during transport using the water-absorbing / drainage function of the temperature-sensitive water-absorbing water retaining agent becomes possible.

It is a figure of the belt conveyor 1 which concerns on this embodiment, (a) is a whole side view, (b) is detailed sectional drawing which follows the EE line. It is the figure which showed the effect | action of the belt conveyor 1 which concerns on this embodiment, (a) is a figure which showed a mode that the conveyance material 11 was dehydrated, (b) was a figure which showed temperature environment. Sectional drawing which showed belt 4 'which concerns on a modification. Sectional drawing which showed the belt 41 which concerns on a modification. The figure which showed the temperature environment at the time of using the belt conveyor which concerns on a modification. The figure which showed the relative temperature relationship with the setting temperature Tmin of a low heat environment, the setting temperature Tmax of a high heat environment, the temperature sensing point T0, and the outside temperature T.

Explanation of symbols

1 Belt conveyor 4, 4 'Belt 5 Belt body 6, 6' Absorption / drainage layer 8 Heater (heating means)
11 Transport material 42 Impervious rubber 43 Temperature-sensitive water-absorbing water retaining agent 51 Cooler (cooling means)

Claims (7)

A belt conveyor configured by suspending an endless belt between a head pulley arranged on the nose side and a tail pulley arranged on the tail end side, and the belt is connected to the conveying surface of the belt body with temperature-sensitive water absorption and drainage A belt conveyor comprising a water absorption / drainage layer made of a water retention agent. A belt conveyor constructed by suspending an endless belt between a head pulley arranged on the nose side and a tail pulley arranged on the tail end side. A belt conveyor characterized in that the belt is constituted by covering a conveyance surface of a belt body with a water absorption / drainage layer formed by mixing a water-retaining agent. It is a belt conveyor constructed by hanging an endless belt between a head pulley arranged on the nose side and a tail pulley arranged on the tail end side, and a temperature-sensitive water-absorbing water retaining agent is mixed into the water-permeable rubber. A belt conveyor characterized in that the belt is constituted by a water-absorbing and draining belt. It is a belt conveyor constructed by hanging an endless belt between a head pulley arranged on the nose side and a tail pulley arranged on the tail end side, and a temperature-sensitive water-absorbing and water-retaining agent is mixed into the impermeable rubber. In addition, a belt conveyor comprising the water-absorbing and draining belt formed so that at least a part of the temperature-sensitive water-absorbing and water-retaining agent is exposed on the conveying surface. The belt conveyor as described in any one of Claims 1 thru | or 4 provided with the cooling means which cools this temperature-sensitive water-absorbing water-retaining agent when the said temperature-sensitive water-absorbing water-retaining agent is in a drainage state. The belt conveyor as described in any one of Claims 1 thru | or 4 provided with the heating means which heats this temperature-sensitive water absorption / drainage water retention agent when the said temperature-sensitive water absorption / drainage water retention agent exists in a water absorption state. The belt conveyor according to any one of claims 1 to 6, wherein excavated earth or dredged earth is used as a conveying material.

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