JP5566578B2 - Salt production equipment - Google Patents

Description

  The present invention relates to a salt production technique using seawater collected from the ocean as a raw material.

  In the process of heating and concentrating natural seawater to produce sodium chloride, calcium sulfate that is not edible is produced, so it is necessary to remove it. Since calcium sulfate is difficult to dissolve in water and has the property of precipitating in water, in the conventional salt making process, the seawater boiled until the salt concentration becomes 12 to 15% in the concentration kettle is transferred to the precipitation removing tank. A technique has been proposed in which calcium sulfate is precipitated in a calm state and then discharged and removed from a drain pipe provided at the lower end of the precipitation removing tank (see, for example, Patent Document 1).

JP 2001-213620 A

  In the salt production method described in Patent Document 1, since the entire amount of seawater boiled in a concentration kettle has to be transferred to a precipitation removing tank, a long time is required for the transfer operation. Further, when calcium sulfate is removed in the precipitation removing tank, a part of the precipitated salt may flow out, which causes the yield to deteriorate.

In addition, the salt production method described in Patent Document 1 is a configuration in which concentrated seawater (supernatant) from which calcium sulfate has been removed in a precipitation removal tank is further transferred to an evaporation crystal kettle to obtain salt, so that at least concentration is performed. kettle, a sedimentation removal tank及beauty evaporation crystallization kettle, and the like requires a large number of pipes for transporting concentrated salt water between these devices has led to complication of salt production facility.

  The problem to be solved by the present invention is to provide a salt production technique capable of simplifying the salt production facility and improving the efficiency of the salt production process.

The salt production facility of the present invention includes a main processing container for storing raw salt water such as natural seawater, a heating means for heating the contents in the main processing container, and a stirring mechanism for stirring the contents in the main processing container. A first drainage path provided at the bottom of the main processing container for discharging the sediment in the concentrated salt water generated in the main processing container, and a crystalline salt generated in the main processing container A second drainage path provided at the bottom of the main processing container for discharging saturated salt water, and an upper end provided in a state of projecting upward from the bottom in the main processing container in communication with the first drainage path A concentrating device having a cylindrical liquid collection part having an opening in
A sub-treatment container containing concentrated salt water containing the precipitate discharged from the main treatment container via the first drainage path; and a re-precipitate formed in the concentrated salt water in the sub-treatment container. A separator having a discharge path provided at the bottom of the sub-processing container for discharging.

  With such a configuration, precipitates such as calcium sulfate generated in the concentrated salt water generated by heating the raw salt water in the main treatment container of the concentrator are separated via the first drainage path. It can be transferred to the secondary processing vessel of the apparatus. At this time, since the precipitate is discharged through the cylindrical liquid collection portion protruding upward from the bottom portion in the main processing container, the crystalline salt deposited on the bottom portion in the main processing container flows out together with the precipitate. Can be suppressed. In addition, since the supernatant concentrated brine after the sediment in the main processing container has been transferred to the sub-processing container remains in the main processing container, the entire amount of the contents in the main processing container is transferred to another processing container. Compared to the case, the transfer time can be shortened.

  When it is left to stand after completion of transfer to the sub-treatment container, a reprecipitation layer such as calcium sulfate is formed at the bottom of the sub-treatment container, and a supernatant concentrated brine is formed above it. It can be selectively discharged via the discharge path at the bottom of the sub-processing container. Moreover, the concentrated salt water (supernatant liquid) remaining in the sub-treatment container can be returned to the main treatment container and again subjected to the heating and concentration step.

  As described above, the salt production facility of the present invention performs concentration of raw salt water and precipitation of calcium sulfate in the main treatment container of the concentration apparatus, and reprecipitation and discharge removal of calcium sulfate and the like in the sub-treatment container of the separation apparatus. In addition, it is not necessary to transfer the entire amount in the main processing container to the sub-processing container, and the efficiency of the salt making process can be improved. In addition, since the concentrated salt water (supernatant) remaining in the sub-treatment container is returned to the main treatment container and again used for the heating and concentration step, the salt production operation should be carried out in the two reaction vessels, the main treatment container and the sub-treatment container. This makes it possible to simplify the salt production facility.

  Here, it is desirable to provide a separating member disposed so as to be able to be taken in and out at the boundary between the re-precipitate formed in the concentrated brine in the sub-treatment container and the supernatant concentrated brine. With such a configuration, remixing of the supernatant concentrated brine formed in the sub-treatment container and the re-precipitate can be prevented, so that the re-precipitate in the sub-treatment container can be efficiently discharged. it can.

  In this case, it is desirable that the bulk density of the separating member is smaller than the specific gravity of the precipitate and larger than the specific gravity of the concentrated salt water. With such a configuration, if the separating member is gently inserted into the sub-treatment container in which the re-precipitate and the supernatant concentrated brine are separated, the separating member is separated from the supernatant concentrated saline by the above-described specific gravity difference. Is settled and stops at the boundary between the supernatant concentrated brine and the re-precipitate, so that the arrangement work is facilitated.

  On the other hand, the bulk density of the isolation member is made smaller than the specific gravity of the supernatant concentrated brine, and the isolation member is submerged to the boundary between the re-precipitate formed in the concentrated brine in the sub-treatment container and the supernatant concentrated brine. Can be detachably attached to the isolation member. With such a configuration, by inserting the isolation member without a weight into the sub-treatment container and floating on the supernatant concentrated salt water, a weight with an appropriate mass is attached to the isolation member. The isolation member can be sunk to the boundary between the re-precipitate and the supernatant concentrated brine. Therefore, even when the specific gravity of the supernatant concentrated brine varies, the isolation member can be accurately arranged at the boundary between the re-precipitate and the supernatant concentrated brine by increasing or decreasing the mass of the weight.

  Here, it is desirable to provide a through hole in the liquid collection part. With such a configuration, the precipitate such as calcium sulfate is discharged through the through hole of the liquid collecting part and then transferred into the sub-processing container, so that the transfer time can be further shortened. In addition, since the salt deposited near the bottom in the processing container quickly forms a bridge when flowing into the through-hole, it is possible to suppress subsequent inflow of salt into the through-hole.

  It is desirable that the peripheral shape of the opening of the second drainage path on the bottom surface in the main processing container is an ellipse or an oval. With such a configuration, when the crystal salt precipitated in the processing vessel is discharged from the second drainage path together with the saturated salt water, it is possible to avoid the formation of a crystal salt bridge in the opening. Therefore, it is effective for improving the efficiency of the drainage work.

On the other hand, the salt production method using the salt production facility according to the present invention includes a primary calming step in which concentrated salt water formed by reducing moisture in raw salt water such as seawater is left in a main processing vessel to generate a precipitate. A secondary calming step of transferring the precipitate generated in the main processing vessel into the sub-processing vessel and allowing it to stand; a separation step of discharging the re-precipitate generated in the sub-processing vessel; and And a step of transferring the concentrated salt water left in the sub-treatment vessel in the separation step into the main treatment vessel, and in the separation step, at the boundary between the re-precipitate in the sub-treatment vessel and the supernatant concentrated salt water. The re-precipitate is discharged in a state where the separating member is arranged.

  With such a configuration, it is possible to concentrate the raw salt water and remove precipitates such as calcium sulfate in the main processing vessel, and to remove reprecipitates such as calcium sulfate in the sub-treatment vessel. Therefore, it is possible to perform salt making operations in the two main and sub processing containers, the simplification of salt making equipment can be achieved, and it is not necessary to transfer the entire amount of the contents of the main processing container to the sub processing container, and the salt making process Can be made more efficient.

Further, in the above separation process, the Rukoto to discharge the re precipitate in a state in which the placing the isolation member in the boundary of the re-precipitates produced sub-processing vessel and concentrated salt water is the supernatant, the sub-process Since remixing of the supernatant concentrated brine formed in the container and the reprecipitate can be prevented, the reprecipitate in the sub-treatment container can be efficiently discharged. In this case, the bulk specific gravity of the separating member can be set larger than the specific gravity of the supernatant concentrated salt water and smaller than the specific gravity of the re-precipitate, or a removable weight can be attached to the separating member.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a salt production technique capable of simplifying a salt production facility and improving the efficiency of a salt production process.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a partially omitted vertical sectional view showing a concentrating device constituting a salt production facility according to an embodiment of the present invention, FIG. 2 is a partially enlarged view of FIG. 1, and FIG. FIG. FIG. 4 is a partially omitted vertical sectional view showing a separation device constituting a salt production facility according to an embodiment of the present invention, and FIGS. 5 and 6 are partially omitted vertical views showing a state in the separation device shown in FIG. It is sectional drawing.

  The salt production facility of the present embodiment includes a concentration device 10x shown in FIG. 1 and a separation device 10y shown in FIG. As shown in FIG. 1, the concentrating device 10 x can store raw salt water such as natural seawater, and a main processing container 11 for performing a subsequent salt making operation, and heating means for the stored material in the main processing container 11. A jacket 16 for passing water vapor, a stirring mechanism 12 for stirring the contents in the main processing container 11, and a bottom 11b of the main processing container 11 for discharging the contents in the main processing container 11. The first drainage path 24 and the second drainage path 25 are provided.

  The first drainage path 24 and the second drainage flow path 25 are provided with on-off valves 24a and 25a, respectively. Although not shown, a suction pump and a condenser for discharging water vapor generated in the main processing container 11, an exhaust pipe communicating the main processing container 11 and the condenser, a condenser and a suction pump, And a suction tube communicating with each other.

  The main processing container 11 is an airtight container in which the central part 11c has a cylindrical shape, and the ceiling part 11a and the bottom part 11b each have a smooth convex curved shape. The main processing container 11 includes a plurality of support columns 15 that are erected on the installation surface G. The shaft center (not shown) of the central portion 11c is fixed in a vertical direction. As shown in FIG. 1, the agitation mechanism 12 rotates and drives a shaft 12a disposed at the axial position in the main processing vessel 11, a propeller-like agitation blade 12b attached to the lower end portion thereof, and the shaft 12a. Therefore, a motor (not shown) and a speed reducer 14 disposed on the ceiling portion 11a of the main processing container 11 are provided. The rotation of the motor (not shown) is transmitted to the shaft 12a via the speed reducer 14, and the stirring blade 12b rotates along the inner surface of the bottom portion 11b as the shaft 12a rotates.

  An air supply tube (not shown) for supplying water vapor into a jacket 16 provided along the lower surface of the bottom portion 11b of the main processing container 11, and an exhaust tube (for discharging water vapor circulated in the jacket 16) (Not shown) is connected to the lower surface of the jacket 16. In addition, a drain (not shown) is provided on the lower surface of the jacket 16 in order to discharge moisture accumulated in the jacket 16.

  As shown in FIGS. 1 to 3, the bottom 11 b in the main processing container 11 communicates with the first drainage path 24 and protrudes upward in the main processing container 11. A portion 26 is provided. An opening 26a is provided at the upper end of the liquid collection part 26, and a plurality of through holes 26b are arranged at equal intervals along the circumferential direction in the vicinity of the boundary between the liquid collection part 26 and the bottom part 11b in the main processing container 11. Is provided. Further, as shown in FIG. 3, the peripheral shape of the opening 25b of the second drainage path 25 that opens to the bottom 11b in the main processing container 11 is elliptical.

  On the other hand, as shown in FIG. 4, the separation device 10 y can accommodate a material (such as a calcium sulfate precipitate) transferred from the main processing container 11 via the first drainage path 24, and has a cylindrical shape. A sub-processing container 60 having a shallow main body portion 60a and a bottom portion 60b having a shallow slope and connected to the lower portion thereof, and a discharge path 27 communicating with the opening 60c at the lower end of the bottom portion 60b. Yes. The discharge path 27 is provided with an on-off valve 27a.

  Next, based on FIGS. 1-6 and FIGS. 7-9, the salt production method by the salt production equipment provided with the concentration apparatus 10x and the separation apparatus 10y is demonstrated. 7 and 8 are vertical sectional views showing a state in the concentrating device, and FIG. 9 is a vertical sectional view showing a state in which the saturated salt water and the crystalline salt are discharged in the concentrating device.

  By adding salt water (not shown) having a salinity higher than that of natural seawater to natural seawater (not shown) stored in the main processing vessel 11, high-concentration seawater having a salt concentration of 18 to 22% by mass is formed. (Concentration step). Then, high-temperature seawater is heated by supplying high-temperature steam to the jacket 16 of the main processing vessel 11 while rotating the stirring blade 12b to evaporate the water (heating process). Thereby, the water | moisture content of the high concentration seawater in the main processing container 11 reduces gradually (start of a primary concentration process).

  In the heating step, since the main processing vessel 11 is kept in an airtight state, water vapor generated from the heated high-concentration seawater passes through an exhaust pipe (not shown) by a suction pump (not shown). Discharged. The water vapor discharged from the main processing vessel 11 is collected in a condenser (not shown), liquefied inside, and then discharged to a predetermined place.

  When the moisture in the high-concentration seawater decreases due to the evaporation of water in the heating step, the suction by a suction pump (not shown) is stopped, and the natural seawater of approximately the same amount as the decreased water is replenished into the main processing vessel 11 ( Replenishment step), and then restart the heating step. When the water in the high-concentration seawater in the main processing container 11 is reduced to a predetermined amount by resuming the heating process, natural seawater is replenished in the same procedure as described above. When such a heating step and a replenishment step are repeated a plurality of times, the high-concentration seawater is gradually concentrated, and a concentrated salt water 30 having a higher salinity is formed, and calcium sulfate 40 is contained in the concentrated salt water 30. Precipitate (end of primary concentration step).

  When the concentrated salt water 30 is formed in the main processing vessel 11 by the primary concentration step, the rotation of the stirring blade 12b and the suction pump (not shown) are stopped, and the supply of water vapor to the jacket 16 is stopped. 1 (primary standing step), a precipitate 40a such as calcium sulfate 40 and concentrated salt water 30 as the supernatant appear in the main processing vessel 11 as shown in FIG. In addition, if cold water is supplied into the jacket 16 and the high-concentration salt water is cooled during the primary standing step, the precipitation rate of the calcium sulfate 40 and the like can be increased.

  After the state shown in FIG. 1 is reached, if the on-off valve 24a of the first drainage path 24 connected to the bottom of the main processing container 11 is opened, the precipitate 40a of the calcium sulfate 40 in the main processing container 11 is drained. It is discharged via the path 24 (purification step) and transferred into the sub-processing container 60 of the separation device 10y as shown in FIG. In this case, as shown in FIG. 2, the crystalline salt S may be deposited on the upper surface of the bottom portion 11b in the main processing vessel 11, but the calcium sulfate 40 precipitated above the crystalline salt S is separated from the bottom portion 11b. Since it flows in into the opening part 26a of the liquid collection part 26 in a higher position, it can suppress that the crystalline salt S flows out with the calcium sulfate 40. FIG.

  In addition, since a plurality of through holes 26b are provided at intervals of 90 degrees along the circumferential direction in the portion near the bottom portion 11b of the liquid collection portion 26, the calcium sulfate 40 precipitated in the vicinity of the bottom portion 11b It is efficiently discharged via the through hole 26b. A part of the crystalline salt S deposited near the bottom 11b in the main processing vessel 11 flows into the through hole 26b immediately after opening the on-off valve 24a, but since a bridge is quickly formed during the inflow, Inflow of the crystalline salt S into the through-hole 26b of can be suppressed.

  Thus, almost the entire amount of calcium sulfate 40 precipitated and precipitated in the main processing container 11 in the primary concentration step is transferred into the sub-processing container 60 of the separation device 10y via the first drainage path 24. The When the calcium sulfate 40 is completely transferred into the sub-processing vessel 60 and left standing (secondary standing step), as shown in FIG. 4, the re-precipitate 40b of the calcium sulfate 40 in the sub-processing vessel 60, The concentrated salt water 30 which is the supernatant appears.

  When the re-precipitate 40b of calcium sulfate 40 and the concentrated salt water 30 are clearly separated in the sub-treatment container 60 from the secondary standing step, as shown in FIG. 5, the concentrated salt water 30 in the sub-treatment container 60 is entered. A non-water-permeable sheet-like isolation member 61 is inserted. Since the bulk specific gravity of the separating member 61 is smaller than the specific gravity of the re-precipitate 40b of the calcium sulfate 40 and larger than the specific gravity of the concentrated salt water 30, the sub-treatment in which the re-precipitate 40b and the supernatant concentrated brine 30 are separated. When the separating member 61 is gently inserted into the container 60, the separating member 61 sinks in the supernatant concentrated brine 30 due to the above-described difference in specific gravity, and as shown in FIG. Since it stops at the boundary with 40b, the arrangement | positioning operation | work of the isolation member 61 is easy.

  After the isolation member 61 is stationary at the boundary between the supernatant concentrated brine 30 and the re-precipitate 40b, when the on-off valve 27a below the sub-treatment container 60 is opened, the re-precipitate 40b is removed from the discharge path 27 as shown in FIG. It is gradually discharged and transferred to a predetermined place. Thus, if the separating member 61 is arranged in the sub-processing container 60, the re-mixing of the supernatant concentrated brine 30 and the re-precipitate 40b formed in the sub-processing container 60 can be prevented. The re-precipitate 40b in 60 can be discharged efficiently.

  When the discharge of the calcium sulfate 40 re-precipitate 40b in the sub-treatment container 60 is completed, the on-off valve 27a is once closed, the isolation member 61 is taken out from the sub-treatment container 60, and the downstream side of the discharge path 27 is shown in FIG. The liquid supply pipe 28 shown in FIG. When the on-off valve 27a is opened, the concentrated salt water 30 in the sub-processing container 60 is transferred into the main processing container 11 of the concentration apparatus 10x, and the concentrated salt water 30 remaining in the main processing container 11 in the purification step. (See Fig. 1).

  Thereafter, the main processing vessel 11 is brought into an airtight state, a motor and a suction pump (both not shown) are operated, high temperature steam is supplied to the jacket 16 to heat the concentrated salt water 30 in the main processing vessel 11. The water in the concentrated brine 30 is evaporated (secondary concentration step). When a predetermined amount of water evaporates from the concentrated salt water 30 in the secondary concentration step, as shown in FIG. 8, the volume decreases and crystal salt S precipitates in the main processing vessel 11, and a saturated salt water 50 is generated as the supernatant. Is done.

  When the secondary concentration step is completed, as shown in FIG. 9, the stirring blade 12b is rotated through the shaft 12a, and the saturated salt water 50 and the crystalline salt S in the main processing vessel 11 are sufficiently stirred. When the saturated salt water 50 and the crystalline salt S are sufficiently mixed by this stirring, the opening / closing valve 25a of the second drainage path 25 provided in the bottom portion 11b is opened, and the saturated salt water 50 and the salt particles S are opened. The mixed fluid is discharged from the main processing container 11 and sent to a predetermined centrifugal separator (not shown).

  As shown in FIG. 3, since the opening 25b of the second drainage path 25 that opens to the bottom 11b in the main processing vessel 11 is elliptical, the crystalline salt S gathers to form a bridge. Can be suppressed. Therefore, the mixed fluid of the saturated salt water 50 and the crystalline salt S is smoothly discharged from the main processing vessel 11 and sent to a centrifugal separator (not shown). Then, when the saturated salt water 50 is separated and removed from the crystalline salt S in the centrifugal separator, the product salt (aggregate of the crystalline salt S) is obtained.

  In the salt production facility of the present embodiment, the precipitate 40a of the calcium sulfate 40 formed by leaving the concentrated salt water 30 formed by heating and concentrating in the main processing container 11 of the concentration apparatus 10x is first discharged. It can be transferred to the sub-processing container 60 of the separation device 10y via the liquid path 24. At this time, the precipitate 40a of the calcium sulfate 40 flows into and discharges from the bottom 11b of the main processing container 11 into the cylindrical liquid collecting section 26 that protrudes upward, and thus is discharged. It is possible to suppress the crystal salt S precipitated in the vicinity of the inner bottom portion 11b from flowing out together with the precipitate 40a of the calcium sulfate 40.

  Moreover, since the concentrated salt water 30 (supernatant liquid) after transferring the precipitate 40a of the calcium sulfate 40 in the main processing container 11 to the sub-processing container 60 remains in the main processing container 11, the total amount in the main processing container 11 is reduced. The transfer time can be shortened compared to the case where the transfer is performed for other processing.

  Further, since the opening / closing valve 27a of the discharge path 27 is opened with the isolation member 61 disposed between the reprecipitate 40b of the calcium sulfate 40 formed in the sub-treatment container 60 and the concentrated salt water 30 of the supernatant, Remixing of the concentrated brine 30 and the calcium sulfate 40 reprecipitate 40b can be prevented. After discharging the re-precipitate 40b of the calcium sulfate 40, the concentrated salt water 30 remaining in the sub-treatment vessel 60 can be returned to the main treatment vessel 11 and again subjected to the concentration step.

  In this way, the concentration of the raw material in the concentrator 10x and the precipitation of the calcium sulfate 40 are performed, and the calcium sulfate 40 is reprecipitated and removed in the separation device 10y, so that the entire amount in the main processing container 11 is subprocessed. Since the trouble of transferring to the container 60 can be saved, the efficiency of the salt making process can be improved. In addition, since the saturated salt water 50 and the crystalline salt S can be formed by the two devices of the concentration device 10x and the separation device 10y, the salt production facility can be simplified.

  Further, since the precipitate 40a of the calcium sulfate 40 in the main processing container 11 of the concentration apparatus 10x is transferred into the sub-processing container 60 through the plurality of through holes 26b as well as the opening 26a of the liquid collection part 26, The transfer time can be further shortened. In addition, since the crystalline salt S deposited near the bottom 11b in the main processing vessel 11 quickly forms a bridge when flowing into the through hole 26b, the subsequent inflow of the crystalline salt S into the through hole 26b is suppressed. Can do.

  In addition, since the peripheral shape of the opening 25b of the second drainage path 25 that opens to the bottom 11 in the main processing vessel 11 is an ellipse, the crystalline salt S precipitated in the main processing vessel 11 together with the saturated brine 50 Since it is possible to avoid the formation of the bridge of the crystal salt S in the opening 25b when being discharged from the second drainage path 25, the drainage operation is effective.

  Next, based on FIG. 10, FIG. 11 and FIG. 12, other embodiments relating to the separation device will be described. 10, FIG. 11 and FIG. 12 are partially omitted vertical sectional views showing a separating apparatus according to another embodiment. 10 to 12, the parts denoted by the same reference numerals as those in FIGS. 1 to 9 are parts having the same structure and function as the constituent parts of the separation device 10 described above, and description thereof is omitted.

  As shown in FIG. 10, the separating member 65 used in the separation device 10v is erected at the center of the float 65a having a shape covering the entire surface of the supernatant concentrated brine 30 in the sub-treatment container 60 and the upper surface of the float 65a. A support pole 65b; a weight mounting portion 65d provided above the support pole 65b to hold the weight 66 in a detachable manner; and a detected body 65c provided below the support pole 65b. The bulk specific gravity of the float part 65a is smaller than the specific gravity of the supernatant concentrated brine 30 and is set to float on the supernatant concentrated brine 30 without the weight 66 attached. Further, a sensor 67 is provided for detecting when the support pole 65b is lowered in the axial direction and the detected body 65c reaches a predetermined position, and closes the on-off valve 27b.

  As shown in FIG. 10, when calcium sulfate 40 is transferred into the sub-treatment container 60 of the separation apparatus 10v and allowed to stand (secondary standing step), the calcium sulfate 40 is re-introduced into the sub-treatment container 60 as described above. The precipitate 40b and the concentrated salt water 30 which is the supernatant appear. In this step, when the re-precipitate 40b of calcium sulfate 40 and the concentrated salt water 30 are clearly separated in the sub-treatment container 60, the separating member 65 without the weight 66 is charged into the sub-treatment container 60 and the float portion 65a floats on the surface of the supernatant concentrated brine 30.

  Then, as shown in FIG. 11, by attaching a weight 66 of an appropriate mass to the weight mounting portion 65d above the support pole 65b protruding from the upper surface opening of the sub-processing container 60, the float of the isolation member 65 is floated. The part 65a is submerged to the boundary between the re-precipitate 40b and the supernatant concentrated brine 30. At this time, the settlement distance of the float portion 65a can be visually confirmed by a scale (not shown) provided on the support pole 65b.

  After the float part 65a of the separating member 65 is stationary at the boundary between the supernatant concentrated brine 30 and the re-precipitate 40b, when the on-off valve 27b below the sub-treatment container 60 is opened, as shown in FIG. 11, the re-precipitate 40b Are gradually discharged from the discharge path 27. At this time, the float 65a and the support pole 65b of the separating member 65 are also lowered as the re-precipitate 40b decreases, so that the re-precipitate 40b is discharged by visually confirming the scale (not shown) of the support pole 65b. The situation can be grasped. Thus, if the separating member 65 is arranged in the sub-processing container 60, the re-mixing of the supernatant concentrated brine 30 and the re-precipitate 40b formed in the sub-processing container 60 can be prevented. The re-precipitate 40b in 60 can be discharged efficiently.

  In the case of the separation apparatus 10v of this embodiment, when the discharge operation of the re-precipitate 40b proceeds and the detected body 65c of the support pole 65b is lowered to a predetermined position, the sensor 67 detects it and automatically closes the on-off valve 27b. Therefore, it is possible to prevent the supernatant concentrated brine 30 from being erroneously discharged after the completion of the discharge of the re-precipitate 40b. If the weight 66 is removed from the weight mounting portion 65d of the support pole 65b after the discharge of the re-precipitate 40b is completed, the float portion 65a floats on the surface of the supernatant concentrated brine 30 and is thus isolated from the sub-treatment container 60. The member 65 can be easily taken out.

  After the separating member 65 is taken out from the sub-processing container 60, the downstream side of the discharge path 27 is communicated with the liquid feeding pipe 28 shown in FIG. However, it is transferred into the main processing container 11 of the concentration apparatus 10x and mixed with the concentrated salt water 30 (see FIG. 1) remaining in the main processing container 11 in the purification step. The subsequent steps are as described based on FIGS.

  As described above, in the isolation member 65, the weight 66 can be attached to and detached from the weight mounting portion 65d of the support pole 65b. Therefore, even when the specific gravity of the supernatant concentrated brine 30 varies, the mass of the weight 66 is increased or decreased. By this, the main-body part 65a of the isolation member 65 can be correctly arrange | positioned in the boundary of the re-precipitate 40b and the supernatant concentrated brine 30.

  Next, the separation device 10z shown in FIG. 12 is capable of accommodating the contents (precipitate such as calcium sulfate) transferred from the main processing container 11 (see FIG. 1) via the first drainage path 24. A cylindrical main body 70a and a sub-treatment container 70 having a funnel-shaped coagulation sedimentation portion 70b continuously provided therebelow, and a discharge path 77 communicating with the opening 70c at the lower end of the coagulation sedimentation portion 70b. Yes. The discharge path 77 is provided with an on-off valve 77a.

  When calcium sulfate precipitates or the like are transferred into the sub-treatment container 70 via the first drainage path 24 and then left to stand (secondary standing step), the calcium sulfate 40 is re-stored in the sub-treatment container 70. Since the precipitate 40c and the supernatant concentrated brine 30 are separated, the re-precipitate 40c is discharged from the discharge path 77 and transferred to a predetermined place when the on-off valve 77a below the sub-treatment container 70 is opened. Since the funnel-shaped coagulation sedimentation part 70b is provided in the lower part of the sub-processing container 70, the calcium sulfate 40 in the reprecipitate 40c can smoothly flow into the opening 70c and be efficiently discharged from the discharge path 27. it can.

  The salt production equipment and the salt production method according to the present invention can be widely used in the field of salt production industry for producing salt from raw salt water such as natural seawater.

It is a partially abbreviated vertical sectional view showing a concentrating device that constitutes a salt production facility according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of FIG. 1. FIG. 2 is a partially omitted cross-sectional view taken along line AA in FIG. 1. It is a partially omitted vertical sectional view showing a separation device constituting the salt production facility according to the embodiment of the present invention. FIG. 5 is a partially omitted vertical sectional view showing a state in the separation apparatus shown in FIG. 4. FIG. 5 is a partially omitted vertical sectional view showing a state in the separation apparatus shown in FIG. 4. It is a vertical sectional view showing a state in the concentrator. It is a vertical sectional view showing a state in the concentrator. It is a vertical sectional view showing a state in which saturated brine and crystalline salt are discharged from the concentrator. It is a partially omitted vertical sectional view showing a separation device according to another embodiment. It is a partially omitted vertical sectional view showing a separation device according to another embodiment. It is a partially omitted vertical sectional view showing a separation device according to another embodiment.

Explanation of symbols

10x Concentrator 10v, 10y, 10z Separator 11 Main processing vessel 11a Ceiling 11b, 60b Bottom 11c Center 12 Stirring mechanism 12a Shaft 12b Stirring blade 14 Reducer 15 Strut 16 Jacket 23 Suction pipe 24 First drainage flow path 25 Second drainage path 24a, 25a, 27a, 27b, 77a On-off valve 28 Liquid supply pipe 26 Liquid collection part 26a, 60c, 70c Opening part 26b Through hole 27, 77 Discharge path 30 Concentrated salt water 40 Calcium sulfate 40a Precipitate 40b, 40c Reprecipitate 50 Saturated salt water 60, 70 Sub-treatment container 60a, 70a Main body 61, 65 Separating member 65a Float 65b Support pole 65c Detected object 65d Weight mounting part 66 Weight 67 Sensor 70b Aggregation sedimentation part G Installation surface S crystal salt

Claims (6)

A main processing container for storing raw salt water such as natural seawater, a heating means for heating the contents in the main processing container, a stirring mechanism for stirring the contents in the main processing container, and the main processing container A first drainage path provided at the bottom of the main processing container for discharging the precipitate in the generated concentrated salt water, and a saturated salt water containing crystalline salt generated in the main processing container A second drainage path provided at the bottom of the main processing container, and a cylindrical shape having an opening at the upper end provided in a state of projecting upward from the bottom in the main processing container in communication with the first drainage path A concentrating device comprising:
A sub-treatment container containing concentrated salt water containing the precipitate discharged from the main treatment container via the first drainage path; and a re-precipitate formed in the concentrated salt water in the sub-treatment container. A salt production facility, comprising: a separation device having a discharge path provided at a bottom portion of the sub-processing container for discharging.   The salt production equipment of Claim 1 provided with the isolation | separation member arrange | positioned so that withdrawing / inserting into the boundary of the reprecipitation formed in the concentrated salt water in the said sub-treatment container, and a supernatant concentrated salt water.   The salt making facility according to claim 2, wherein the bulk density of the separating member is smaller than the specific gravity of the precipitate and larger than the specific gravity of the supernatant concentrated brine.   The bulk density of the isolation member is smaller than the supernatant concentrated brine, and a weight for sinking the isolation member to the boundary between the re-precipitate formed in the concentrated brine in the sub-treatment container and the supernatant concentrated brine is The salt making equipment according to claim 2, which is detachably attached to the isolation member.   The salt making equipment according to any one of claims 1 to 4, wherein a through hole is provided in the liquid collection part.   The salt making facility according to any one of claims 1 to 5, wherein a peripheral shape of an opening of the second drainage path on a bottom surface in the main processing container is an ellipse or an oval.

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