JP6668169B2 - Vaporizer - Google Patents

Description

  The present invention relates to a vaporizer for vaporizing a liquefied gas that is a low-temperature fluid.

  2. Description of the Related Art Conventionally, as a vaporizer for vaporizing various liquefied gases such as LNG (liquefied natural gas), which is a low-temperature fluid, an open rack vaporizer is known in Patent Document 1 and the like.

  When LNG is vaporized by this type of vaporizer, a heating liquid such as seawater having a higher temperature than LNG is used as a heat source. That is, heat is exchanged between the LNG and the seawater through the heat transfer tube by flowing LNG into the heat transfer tube and flowing seawater along the outer surface of the heat transfer tube. Thereby, LNG is vaporized by the heat received from seawater.

  The open rack type vaporizer described in Patent Document 1 has a panel having a number of heat transfer tubes extending in a vertical direction, and troughs arranged on both sides of the panel. In the open rack type vaporizer, seawater is continuously supplied to the trough, and the seawater overflows from the upper opening of the trough and flows down along the surface of the heat transfer tube. Thus, while continuously supplying seawater to the surface of the heat transfer tube to form a liquid film flow by the seawater on the surface, that is, a so-called liquid film flow, heat exchange between the LNG and the seawater via the heat transfer tube. It is possible to do.

JP-A-10-103896

  In the above evaporator, seawater flows down along the surface of the heat transfer tube from the top of the heat transfer tube, so the seawater disturbs the surface of the liquid film while flowing down the surface of the heat transfer tube, causing the liquid film flow to entrain air. , So-called air entrapment may occur.

  When air entrainment of such a liquid film flow occurs, a liquid film flow covering the surface of the heat transfer tube separates from the surface, that is, a so-called liquid film separation occurs, which may reduce the heat transfer coefficient of seawater. is there. Further, when the amount of cold heat of LNG is constant, the product of the temperature difference between seawater and the surface of the heat transfer tube multiplied by the heat transfer coefficient of seawater is equal to the amount of cold heat of the LNG, so that the heat transfer coefficient of seawater decreases. If this is the case, the temperature difference between seawater and the surface of the heat transfer tube increases in inverse proportion. Therefore, when the seawater temperature is low, the seawater is easily frozen on the surface of the heat transfer tube, and the amount of icing may increase.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vaporizer capable of suppressing air entrapment of seawater flowing down the surface of a heat transfer tube.

In order to solve the above-mentioned problem, a vaporizer according to claim 1 of the present invention vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas. A heat transfer tube panel in which a plurality of heat transfer tubes into which the liquefied gas is introduced are arranged in an upright state, and the heat transfer tube panel extends in a direction in which the plurality of heat transfer tubes are arranged. A trough which is disposed along the outer surface of each heat transfer tube to form a liquid film flow by the heating liquid on the outer surface of the heat transfer tube by continuously flowing the heating liquid along the outer surface of each heat transfer tube; An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the liquid film flow and joins the additional heating liquid to the liquid film flow . Liquid film flow and air entrainment In the height range of the heat transfer tube flows occur repeatedly, characterized in that to merge the additional heating liquid to the liquid film flow.

  In such a configuration, the trough causes the heating liquid to continuously flow down along the outer surface of each heat transfer tube, thereby forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube. In this state, the intermediate supply unit supplies the additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow. The liquid film flow descending along the outer surface of the heat transfer tube is pressed against the heat transfer tube by the additional heating liquid when joining with the additional heating liquid, so that the liquid film surface is stabilized. Therefore, it is possible to suppress the possibility that the liquid film flow entrains air. Accordingly, the flow of the liquid film covering the surface of the heat transfer tube can be prevented from separating from the surface, and a decrease in the heat transfer coefficient of the heating liquid flowing down the surface of the heat transfer tube can be suppressed. As a result, the amount of icing on the surface of the heat transfer tube can be reduced.

In the liquid film flow, a phenomenon occurs in which the flow state becomes discontinuous due to the above-described air entrainment, and the liquid film flow and the air entrainment flow are repeatedly generated. Therefore, in the above configuration, the intermediate supply unit joins the additional liquid for heating to the liquid film flow in the height range of the heat transfer tube where the liquid film flow and the air entrainment flow occur repeatedly . With this configuration , it is possible to stabilize the liquid film surface more effectively, and to further suppress the possibility that the liquid film flow causes air entrainment in which air is entrained. Thus, it is possible to further suppress a decrease in the heat transfer coefficient of the heating liquid due to the liquid film peeling, and it is possible to further reduce the amount of icing when the temperature of the heating liquid is low.

The vaporizer according to claim 2 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas is A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough And an intermediate supply unit for supplying the heating liquid of the liquid film flow and merging the additional heating liquid with the liquid film flow, the intermediate supply unit being caused by air entrainment of the liquid film flow. The heat transfer coefficient of the heating liquid In the height range of the heat transfer tube to be lowered, it characterized Rukoto is combined with the additional heating liquid to the liquid film flow.

  When the change in the heat transfer coefficient of the heating liquid flowing down the surface of the heat transfer tube is viewed in the height direction of the heat transfer tube, the liquid film flows through the air as the heating liquid flows down the surface of the heat transfer tube. Phenomenon that the heating liquid decreases in a certain height range of the heat transfer tube due to the inflow, that is, at a position of a certain first height, the heat transfer coefficient of the heating liquid starts to decrease and the heat transfer coefficient becomes lower than the first height. It has been found by experiments of the present inventor that the phenomenon of the end of the decrease and the increase of the heat transfer coefficient occurs again at the position of the second height below. Therefore, as in the above configuration, the intermediate supply unit is added to the liquid film flow in the height range of the heat transfer tube where the heat transfer coefficient of the heating liquid is reduced due to the entrainment of the heating liquid in the air. It is possible to stabilize the liquid film surface more effectively by joining the heating liquids, and to further suppress the possibility that the liquid film flow causes air to be entrained. Thus, it is possible to further suppress a decrease in the heat transfer coefficient of the heating liquid due to the liquid film peeling, and it is possible to further reduce the amount of icing when the temperature of the heating liquid is low.

The vaporizer according to claim 3 of the present invention is a vaporizer which vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough And an intermediate supply unit that supplies the heating liquid of the heat transfer tube and joins the additional heating liquid to the liquid film flow, wherein the intermediate supply unit has a height of not more than half of the total height of the heat transfer tube. The liquid film flow Characterized Rukoto is combined with the additional heating liquid to.

  With such a configuration, the intermediate supply unit joins the additional heating liquid to the liquid film flow in a range of a height equal to or less than half of the total height of the heat transfer tube in which air entrainment of the heating liquid easily occurs, By stabilizing the liquid film surface more effectively, it is possible to further suppress the possibility that the liquid film flow causes air entrainment in which air is entrained. Thus, it is possible to further suppress a decrease in the heat transfer coefficient of the heating liquid due to the liquid film peeling, and it is possible to further reduce the amount of icing when the temperature of the heating liquid is low.

  Further, when the liquefied gas is introduced from the lower end of the heat transfer tube and exchanges heat with the heating liquid outside the heat transfer tube while the liquefied gas rises inside the heat transfer tube, the height of the heat transfer tube is less than half of the total height. In the range, the liquefied gas undergoes a phase change from liquid to gas, so as described above, by further suppressing the decrease in the heat transfer coefficient of the heating liquid in the range, the liquefied gas can be more efficiently vaporized. Is possible.

The vaporizer according to claim 4 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas is A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough An intermediate supply unit for supplying the heating liquid of the liquid film flow and merging the additional heating liquid with the liquid film flow. The inflow angle θ into the flow is 0 such that θ ≦ 60 °, and wherein the Rukoto is combined with the additional heating liquid to the liquid film flow.

  When the additional heating liquid flows into the liquid film flow within the above range, the heating liquid can be combined with the liquid film flow without disturbing the liquid film flow.

The vaporizer according to claim 5 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough And an intermediate supply unit that supplies the heating liquid of the liquid film flow and merges the additional heating liquid with the liquid film flow. Spills when spilled from department Degree U is,

(Where θ ₁ is the angle with respect to the horizontal plane when the additional heating liquid flows out of the intermediate supply unit, L is the horizontal movement distance of the additional heating liquid from the intermediate supply unit to the liquid film flow, and g is the gravity Acceleration)
So that, characterized Rukoto is combined with the additional heating liquid to the liquid film flow.

  When the additional heating liquid flows into the liquid film flow within the above range, the heating liquid can be combined with the liquid film flow without disturbing the liquid film flow.

  The vaporizer, a trough supply pipe connected to the trough, a pump that sends the heating liquid to the trough through the trough supply pipe, one end is connected in the middle of the trough supply pipe, the other end An intermediate supply pipe connected to the intermediate supply unit.

  In such a configuration, a part of the heating liquid sent from the pump to the trough via the trough supply pipe can be sent to the intermediate supply section via the intermediate supply pipe. It becomes possible to distribute the heating liquid to the respective supply units. Therefore, it is possible to prevent the entrainment of air in the liquid film flow by the additional heating liquid supplied from the intermediate supply unit without increasing the pump power, and to improve the heat transfer performance of the heating liquid. It is possible.

The vaporizer according to claim 7 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas, A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough An intermediate supply unit that supplies the heating liquid of the above, and joins the additional heating liquid to the liquid film flow, a trough supply pipe connected to the trough, and the trough supply pipe. To the trough via A pump that sends a heating liquid, a bypass line that returns a part of the heating liquid discharged from the pump to a supply source of the heating liquid, one end of which is connected in the middle of the bypass line, and the other end of which is characterized that you have further comprising an intermediate supply tube connected to the intermediate feed unit.

  In such a configuration, a part of the heating liquid returned to the heating liquid supply source via the bypass line can be sent to the intermediate supply unit via the intermediate supply pipe. Therefore, it is possible to prevent the entrainment of air in the liquid film flow by the additional heating liquid supplied from the intermediate supply unit without increasing the pump power, and to improve the heat transfer performance of the heating liquid. It is possible. Moreover, in this configuration, the flow rate of the heating liquid sent from the pump to the trough via the trough supply pipe is not reduced by the heating liquid sent to the intermediate supply section via the bypass line, so that the flow from the trough to the heat transfer pipe decreases. The heat transfer performance of the heating liquid does not decrease.

The vaporizer according to claim 8 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas is A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough And an intermediate supply unit that supplies the heating liquid of the liquid film flow and joins the additional heating liquid to the liquid film flow. The intermediate supply unit extends in a direction in which the plurality of heat transfer tubes are arranged. To the heat transfer tube panel A tubular member disposed Wait, characterized Rukoto comprising a tubular member having a plurality of supply ports for supplying said additional heating liquid toward the outer surface of each heat transfer tube in its circumferential surface.

  In such a configuration, it is possible to supply additional heating liquid dispersedly from the plurality of supply ports to the outer surface of each heat transfer tube, and air entrainment of the liquid film flow is performed using a small amount of additional heating liquid. It is possible to reliably suppress it.

  The heat transfer tube includes a tubular main body in which a passage through which the liquefied gas passes is provided, and a plurality of fins protruding outward from an outer peripheral surface of the main body. The additional heating liquid may be supplied from the supply port toward a range including an area between an outer surface of the fin provided at a position closest to the tubular member and a fin adjacent thereto. .

  In the case of the intermediate supply section having the tubular member as described above, the supply port is added from the supply port to the outer surface of the heat transfer tube to a range including a region sandwiched between the fin closest to the tubular member and the fin adjacent thereto. By supplying the heating liquid of the above, the additional heating liquid supplied to the area flows on the peripheral surface of the heat transfer tube from a position close to the intermediate supply part to a position far from the intermediate supply part, so that additional fins are also supplied to other fins. It becomes possible to apply liquid. This makes it possible to improve the effect of suppressing the entrainment of air in the liquid film flow by the additional heating liquid. Further, in this case, since the additional heating liquid flows from the position close to the intermediate supply section to the position far from the intermediate supply unit, the tubular member is arranged close to the heat transfer tube without impairing the air entrainment effect. Becomes possible. Furthermore, the additional heating liquid flows through the heat transfer tube from a position close to the intermediate supply unit to a position farther from the intermediate supply unit, so that it is possible to suppress scattering of the liquid film flow when the additional heating liquid joins the liquid film flow. Become.

  The intermediate supply unit is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged, and by causing the additional heating liquid to flow down along the outer surface of each heat transfer tube, A sub trough for joining the additional heating liquid to the liquid film flow may be provided.

  In such a configuration, by causing the additional heating liquid to flow down along the outer surface of each heat transfer tube from the sub trough along the liquid film flow, the additional liquid is applied to the liquid film flow on the outer surface of each heat transfer tube. It is possible to reliably join the heating liquids.

The vaporizer according to claim 11 of the present invention is a vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid having a higher temperature than the liquefied gas, wherein the liquefied gas is A plurality of heat transfer tubes to be introduced are arranged side by side in a standing state, and a heat transfer tube panel is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged. By continuously flowing down along the outer surface of each heat transfer tube, a trough forming a liquid film flow by the heating liquid on the outer surface of the heat transfer tube, and a trough added toward the heating liquid flowing down from the trough And an intermediate supply unit for supplying the heating liquid of the liquid film flow and merging the additional heating liquid with the liquid film flow , wherein the intermediate supply unit has a flow rate lower than the flow rate of the liquid film flow. Of said additional heating liquid Characterized Rukoto are merged in the liquid film flow.

  In such a configuration, the average flow velocity of the liquid film flow can be reduced by joining an additional heating liquid having a flow velocity lower than the flow velocity of the liquid film flow to the liquid film flow. Entanglement can be reliably suppressed.

  As described above, according to the vaporizer of the present invention, it is possible to suppress the entrainment of seawater flowing down the surface of the heat transfer tube.

It is a figure showing roughly the whole composition of the vaporization device concerning an embodiment of the present invention. It is the figure which looked at the heat exchanger tube panel of FIG. 1, and its peripheral part from the front side of the said heat exchanger tube panel. (A) is an explanatory view showing how seawater is supplied to the outer surface of the heat transfer tube from the trough and the sparge pipe, and (b) shows how the liquid film flow and additional seawater merge on the outer surface of the heat transfer tube. FIG. (A) is a figure which shows arrangement | positioning of the trough and the heat transfer tube of FIG. 1, (b) is a graph which shows the relationship between heat transfer tube height and seawater side heat transfer efficiency ho. (A) is a figure which shows the state of the liquid film flow in a stable area, (b) is a figure which shows the state in which air entrainment of the liquid film flow is occurring in the air entrainment section. It is a graph which shows the relationship between the distance from the lower end of the heat exchanger tube and the heat transfer coefficient of seawater in the case of this embodiment and a comparative example. It is a figure which shows typically the inflow angle (theta) and the outflow velocity U of the additional seawater which joins a liquid film flow. (A) is a diagram showing a state in which the sparged pipe of FIG. 1 supplies additional seawater near the fin closest to the heat transfer tube, and (b) is a comparative example in which the sparged pipe has additional seawater near the fin farthest from the heat transfer tube. It is a figure which shows the state which supplies. It is a figure which shows roughly the whole structure of the vaporization apparatus provided with the sub trough which concerns on the modification of this invention. (A) is an explanatory view showing a state where seawater is supplied to the outer surface of the heat transfer tube from the trough and the sub trough of FIG. 9, and (b) is a state where the liquid film flow and additional seawater join on the outer surface of the heat transfer tube. FIG. It is a figure which shows schematically the whole structure of the vaporizer in which the sparge pipe | tube which concerns on the other modification of this invention was connected to the bypass line via the intermediate | middle supply pipe. It is a figure which shows roughly the whole structure of the vaporization apparatus with which the sub trough which concerns on the other modification of this invention was connected to the bypass line via the intermediate supply pipe. It is a table | surface which shows the relationship between the inflow angle of additional seawater, and the scattering of a liquid film.

  Hereinafter, embodiments of the vaporizer of the present invention will be described in more detail with reference to the drawings.

  The vaporizer 1 of the present embodiment vaporizes LNG as a liquefied gas by performing heat exchange between LNG as a liquefied gas and seawater as a heating liquid higher than the LNG.

  The liquefied gas vaporized by the vaporizer 1 may be other than LNG (for example, liquefied nitrogen). Further, the heating liquid may be a liquid other than seawater, for example, water (specifically, industrial water or the like), an ethylene glycol aqueous solution, or the like.

  As shown in FIG. 1, the vaporizer 1 includes a heat transfer pipe panel 2, a trough 3, a sparge pipe 4 (intermediate supply unit) for supplying seawater to the heat transfer pipe panel 2 below the trough 3, and a trough 3. A connected trough supply pipe 6, a pump 5, and an intermediate supply pipe 7 are provided.

  As shown in FIG. 2, the heat transfer tube panel 2 is configured such that a plurality of heat transfer tubes 11 into which LNG is introduced are arranged in an upright state. Specifically, the heat transfer tube panel 2 includes a plurality of heat transfer tubes 11 erected in the vertical direction, a supply-side header 12 communicating with the lower end openings of these heat transfer tubes 11, and an upper end opening of these heat transfer tubes 11. And a collecting side header 13 which communicates with each other. In the vaporizer 1, the plurality of heat transfer tube panels 2 are arranged at an interval from each other, the supply header 12 is connected to the supply manifold 14 for each heat transfer tube panel 2, and the collection header 13 is connected to the collection manifold 15. Connected.

  In the present invention, the shape of the heat transfer tube 11 is not particularly limited. For example, as shown in FIG. 8A, the heat transfer tube 11 has a tubular main body having a flow path through which LNG passes. 11b and a plurality of fins 11c protruding outward from the outer peripheral surface of the main body.

  As shown in FIGS. 1 and 2, the trough 3 is a long box having an open upper surface, and has a so-called gutter shape. The troughs 3 are arranged along the heat transfer tube panel 2 on both sides of each heat transfer tube panel 2 so as to extend in a direction in which the plurality of heat transfer tubes 11 are arranged. Each trough 3 is supplied with seawater from the sea via a trough supply pipe 6 using a pump 5. The trough supply pipe 6 has a main pipe 6a connected to an outlet of the pump 5, and a distribution section 6b for distributing seawater sent through the main pipe 6a to each trough 3.

  The trough 3 causes the seawater supplied via the trough supply pipe 6 to overflow from the upper surface opening, and causes the seawater to continuously flow down along the outer surface 11a of each heat transfer pipe 11. Thus, a liquid film flow W1 (see FIGS. 3 to 5) due to seawater is formed on the outer surface 11a of the heat transfer tube 11.

  In the vaporizer 1, LNG is introduced into the inside of each heat transfer tube 11 from the lower side via the manifold 14 and the header 12 on the supply side with respect to the plurality of heat transfer tubes 11 which are set up vertically. At the same time, seawater flows down from above along the outer surface 11a of the heat transfer tube 11 via the trough 3. Thereby, heat exchange is performed between the LNG rising inside the heat transfer tube 11 and the seawater descending outside the heat transfer tube 11 via the heat transfer tube 11. Thereby, the LNG is vaporized. NG (natural gas) vaporized from the LNG is sent from the vaporizer 1 to other external equipment via the collecting header 13 and the manifold 15.

  The sparge pipe 4 supplies the additional seawater W2 toward the seawater flowing down from the trough 3, and the additional seawater W2 (see FIG. 3 (a)) with respect to the liquid film flow W1 formed by the seawater flowing down from the trough 3. ) To (b) function as an intermediate supply unit for merging.

  Specifically, the sparge pipe 4 is a tubular member that is horizontally arranged along the heat transfer tube panel 2 so as to extend in a direction in which the plurality of heat transfer tubes 11 are arranged. The sparge pipe 4 has a plurality of supply ports 4 a (see FIGS. 1 and 2) for supplying additional seawater W2 to the outer surface 11 a of each heat transfer pipe 11 on the peripheral surface.

  One end of the intermediate supply pipe 7 is connected in the middle of the trough supply pipe 6 (specifically, the distribution section 6 b thereof), and the other end is connected to the sparge pipe 4. Thereby, a part of the seawater supplied to the trough 3 via the trough supply pipe 6 can be sent to the sparge pipe 4.

  Further, the vaporizer 1 of the present embodiment further includes a bypass line 8 for returning a part of the seawater discharged from the pump 5 to a seawater supply source, and a bypass valve 9 for opening and closing the bypass line 8. The bypass line 8 communicates between the main pipe 6a of the trough supply pipe 6 on the outlet side of the pump 5 and the sea, which is a supply source of seawater. By adjusting the flow rate of seawater flowing through the bypass line 8, it is possible to adjust the flow rate of seawater sent from the pump 5 to the trough 3 via the trough supply pipe 6. Moreover, by mixing the wastewater from the vaporizer 1 with the seawater passing through the bypass line 8, it is possible to return the wastewater to the sea after adjusting the temperature of the wastewater.

  The seawater flowing down along the outer surface 11a of the heat transfer tube 11 forms a liquid film flow W1 from the upper end of the heat transfer tube 11, but the heat transfer performance of the seawater is lowered at the lower portion of the heat transfer tube 11 due to the air entrainment of the liquid film flow W1. It has been found through experiments and the like by the present inventor. Since a phase change of LNG (a change from a liquid to a gas) occurs in the lower portion of the heat transfer tube 11, a decrease in the heat transfer performance of seawater in the lower portion of the heat transfer tube 11 has a large effect on the performance of the entire vaporizer 1.

  Therefore, in the vaporizer 1 of the present embodiment, a decrease in heat transfer performance is suppressed by joining the additional seawater W2 of the lateral flow from the sparge pipe 4 to the liquid film flow W1 flowing down the heat transfer tube 11 vertically downward. ing. This will be described in detail below.

  FIG. 4A is a diagram showing the speed at each height position of the liquid film flow W1 flowing down the outer surface 11a of the heat transfer tube 11 when there is no sparge tube 4 (intermediate supply unit). FIG. 4B is a graph showing the distribution of the heat transfer coefficient ho on the seawater side in the height direction of the heat transfer tube 11. As shown in FIG. 4B, the seawater flowing down from the trough 3 reaches the lower end of the heat transfer tube 11 through three regions (a running section, a stable section, and an air entrainment section) from the top of the heat transfer tube 11. I do. Specifically, when flowing down from the trough 3, the velocity of the seawater is gradually accelerated by gravity. Accordingly, the heat transfer coefficient increases, and the liquid film thickness also decreases. This area is generally called an approach section. After being accelerated in the approach section, when the speed becomes a certain speed or more, the liquid film thickness becomes a constant value and becomes stable (the state of the liquid film flow W1 shown in FIG. 5A). This area is called a stable section. Thereafter, the stable liquid film flow W1 starts to be disturbed due to the liquid film surface waving. At this time, air entrainment occurs because the liquid film flow W1 entrains air (a state in which air entrapment C in FIG. 5B occurs). This area is called an air entrainment section.

  In the vaporizer 1 of the above embodiment, as shown in FIGS. 3A and 3B, the trough 3 causes the seawater to continuously flow down along the outer surface 11 a of each heat transfer tube 11. Thus, a liquid film flow W1 due to seawater is formed on the outer surface 11a of the heat transfer tube 11. In this state, the sparge pipe 4 supplies the additional seawater W2 toward the seawater flowing down from the trough 3, and joins the additional seawater W2 with the liquid film flow W1. The liquid film flow W1 descending along the outer surface 11a of the heat transfer tube 11 is pressed against the heat transfer tube 11 by the additional seawater W2 when it joins with the additional seawater W2, so that the liquid film surface is stabilized. Further, the average flow velocity of the liquid film flow W1 is reduced by adding the seawater W2. Therefore, it is possible to suppress the possibility that the liquid film flow W1 causes air entrainment C (see FIG. 5B) in which air is entrained. Thereby, the liquid film flow W1 covering the outer surface 11a of the heat transfer tube 11 can suppress the separation from the outer surface 11a, and can suppress a decrease in the heat transfer coefficient of the seawater flowing down the outer surface 11a of the heat transfer tube 11. It is. As a result, the amount of icing on the outer surface 11a of the heat transfer tube 11 can be reduced.

  In order to verify the effect of suppressing the decrease in the heat transfer coefficient of seawater by the vaporizer 1 of the present embodiment, the inventor conducted an experiment, and the experiment result is shown in FIG. FIG. 6 shows the relationship between the standardized distance d from the heat transfer tube lower end and the heat transfer coefficient ho standardized by the average heat transfer coefficient (for example, the average value of the heat transfer coefficient of seawater over the entire length of the heat transfer tube). Show. The result of Comparative Example α in the case where the additional seawater W2 is not merged with the liquid film flow W1 is indicated by a square point, and the result of the present embodiment β in which the additional seawater W2 is merged with the liquid film flow W1 is the round point. Indicated by

  As is clear from FIG. 6, in the comparative example α in which the additional seawater W2 is not merged with the liquid film flow W1, the liquid film flow W1 passed through the approach section I and the stable section II in the process of descending. Thereafter, air entrainment of the liquid film flow W1 starts to occur from around a half height position (d = 0.5) with respect to the entire length of the heat transfer tube 11. Then, in the range B after the stable section II, the flow state of the liquid film flow W1 becomes unstable and the air entrainment section III starts. It can be seen that in the air entrainment section III, the liquid film flow W1 has a low heat transfer coefficient ho of the seawater due to the air entrainment of the liquid film flow W1.

  On the other hand, in the present embodiment β in which the additional seawater W2 is merged with the liquid film flow W1, the liquid film flow is set at a position not higher than a half height position (d = 0.5) with respect to the entire length of the heat transfer tube 11 (d = 0.5). The additional seawater W2 joins the stream W1. Thereby, also in the air entrainment section III, the entrainment of the liquid film flow W1 in the liquid film flow W1 is suppressed. Therefore, it can be seen that the heat transfer coefficient ho of seawater is improved as a whole as compared with the case of Comparative Example α described above. According to the experiment of the present inventor, in the present embodiment β, it is confirmed that the heat transfer coefficient ho of the seawater in the air entrainment section III is improved by about 30% as compared with the comparative example α.

  Based on the experimental results of FIG. 6 described above, the range of the height at which the additional seawater W2 joins the liquid film flow W1 is defined as, for example, the following (condition 1) to (condition 3).

(Condition 1)
The sparge pipe 4 may allow the additional seawater W2 to join the liquid film flow W1 in the height range of the heat transfer tube 11 where the liquid film flow W1 and the air entrainment flow occur repeatedly.

  In the range B after passing through the stable space II in FIG. 6, the liquid film flow W1 becomes discontinuous due to the above-described air entrainment, and the liquid film flow W1 and the air entrainment flow (that is, FIG. 5 (b), a phenomenon in which the liquid film flow in which the air entrainment C has occurred) occurs repeatedly. Therefore, in the height range (range B in FIG. 6) of the heat transfer tube 11 where the liquid film flow W1 and the air entrainment flow occur repeatedly, the sparge pipe 4 joins the additional seawater W2 with the liquid film flow W1. Thereby, it is possible to stabilize the liquid film surface more effectively, and to further suppress the possibility that the liquid film flow W1 entrains air. As a result, it is possible to further suppress a decrease in the heat transfer coefficient of the seawater caused by the liquid film peeling, and to further reduce the amount of icing in a state where the temperature of the seawater is low.

(Condition 2)
In the air entrainment section III shown in the graph of FIG. 6, the sparge pipe 4 applies the liquid film flow W1 to the liquid film flow W1 in a height range where the heat transfer coefficient ho of the seawater decreases due to the air entrapment of the liquid film flow W1. On the other hand, additional seawater W2 may be merged.

As shown in the graph of FIG. 6 described above, a case is considered in which the change in the heat transfer coefficient of seawater flowing down the outer surface 11a of the heat transfer tube 11 is viewed in the height direction of the heat transfer tube 11. In this case, as the seawater flows down along the outer surface 11a of the heat transfer tube 11, the phenomenon that the heating liquid drops in a certain height range of the heat transfer tube due to the entrainment of the liquid film flow W1 in the air, that is, At a certain first height position (ie, the ho reduction start point P ₁ in FIG. 6), the heat transfer coefficient of seawater starts to decrease, and a second height position below the first height (ie, It has been found from experiments by the present inventor that the heat transfer coefficient ends up decreasing at the ho return start point P ₂ ) in FIG. 6 and the heat transfer coefficient increases again. Therefore, as in the configuration described above, sparge tube 4, from the point P ₁ of the height range (FIG. 6 of the heat transfer tube 11 due to the seawater air entrainment decreases the heat transfer rate of the seawater to the point P ₂ ), The additional seawater W2 is combined with the liquid film flow W1. Thereby, it is possible to stabilize the liquid film surface more effectively, and to further suppress the possibility that the liquid film flow W1 entrains air. As a result, it is possible to further suppress a decrease in the heat transfer coefficient of seawater due to the liquid film peeling, and to further reduce the amount of icing in a state where the temperature of the seawater is low.

(Condition 3)
The sparging pipe 4 may allow the additional seawater W2 to join the liquid film flow W1 in a range of a height equal to or less than half of the total height of the heat transfer pipe 11.

  That is, the sparge pipe 4 has a liquid film flow W1 within a range of a height equal to or less than half of the total height of the heat transfer tube 11 in which seawater air is likely to be entrained (that is, a range where d in FIG. 6 is 0.5 or less). On the other hand, the additional seawater W2 is merged. Thereby, it is possible to stabilize the liquid film surface more effectively, and to further suppress the possibility that the liquid film flow W1 entrains air. As a result, it is possible to further suppress a decrease in the heat transfer coefficient of the seawater caused by the liquid film peeling, and to further reduce the amount of icing in a state where the temperature of the seawater is low.

  In the vaporizer 1 of the present embodiment, LNG is introduced from the lower end of the heat transfer tube 11 and exchanges heat with seawater outside the heat transfer tube 11 while rising inside the heat transfer tube 11. In this case, in a range where the height of the heat transfer tube 11 is less than half of the total height (a range where d in FIG. 6 is 0.5 or less), LNG changes phase from liquid to gas (see the LNG phase change portion in FIG. 6). ). As described above, it is possible to more efficiently vaporize LNG such as LNG by further suppressing a decrease in the heat transfer coefficient of seawater in a range of a height equal to or less than half of the total height of the heat transfer tube 11.

  It is preferable that the sparge pipe 4 join the additional seawater W2 having a flow rate lower than the flow rate of the liquid film flow W1 to the liquid film flow W1. By joining additional seawater W2 having a flow rate lower than the flow rate of the liquid film flow W1 to the liquid film flow W1, the average flow velocity of the liquid film flow W1 can be reduced, and the air flow of the liquid film flow W1 can be reduced. Intrusion can be reliably suppressed.

  Further, the flow rate of the additional seawater W2 is preferably 30% or less of the flow rate of the liquid film flow W1. If the flow rate of the additional seawater W2 is set in such a range, the scattering of the liquid film flow W1 can be suppressed. Further, it is possible to suppress a decrease in the flow rate of the liquid film flow W <b> 1 and to suppress a decrease in the heat exchange amount of seawater in the upper part of the heat transfer tube 11.

  As shown in FIG. 7, the sparge pipe 4 has an inflow angle θ at which the additional seawater W2 flows into the liquid film flow W1 (that is, an angle at which the seawater W2 contacts the surface of the liquid film flow W1). It is preferable that the additional seawater W2 is combined with the liquid film flow W1 so that 0 <θ ≦ 60 °. When the additional seawater flows into the liquid film flow W1 within this range, the seawater can be combined with the liquid film flow W1 without disturbing the liquid film flow W1. When the present inventor confirmed through experiments, as shown in FIG. 13, the scattering of the liquid film was not confirmed when the inflow angle θ was 60 ° or less, but the scattering of the liquid film was confirmed in the range larger than 60 °. I have.

  Here, as shown in FIG. 7, the sparge pipe 4 needs to set the outflow speed U when the additional seawater W2 flows out of the sparge pipe 4 so that the inflow angle θ is 60 ° or less. There is.

As shown in FIG. 7, the angle of the additional seawater W2 with respect to the horizontal plane when flowing out from the supply port 4a of the sparge pipe 4 is θ ₁ , and the horizontal movement distance of the additional seawater W2 from the sparge pipe 4 to the liquid film flow W1. Is L and the gravitational acceleration is g, the outflow velocity U at which the above-mentioned inflow angle θ is 60 ° or less can be obtained as in the following equations (1) to (6).

Therefore, the sparge pipe 4 has an outflow speed U when the additional seawater W2 flows out of the sparge pipe 4,

It is preferable to add the additional seawater W2 to the liquid film flow W1 such that When the additional seawater W2 flows into the liquid film flow W1 at the outflow velocity U within the above range, the above inflow angle θ becomes 60 ° or less, so that the seawater is removed without disturbing the liquid film flow W1. It is possible to join the flow W1.

  In the vaporizer 1 of the above embodiment, the intermediate supply pipe 7 has one end connected to the middle of the trough supply pipe 6 and the other end connected to the sparge pipe 4. Therefore, a part of the seawater sent from the pump 5 to the trough 3 via the trough supply pipe 6 can be sent to the sparge pipe 4 via the intermediate supply pipe 7, so that the trough 3 And seawater can be distributed to the sparge pipe 4 respectively. Therefore, it is possible to prevent the entrainment of air in the liquid film flow W1 by the additional seawater W2 supplied from the sparge pipe 4 without increasing the pump power, and it is possible to improve the heat transfer performance of seawater. is there.

  At the upper part of the heat transfer tube 11, the vaporization of LNG has been completed, but the upper part of the heat transfer tube 11 is used for heating the generated natural gas (NG). Since natural gas flows inside the heat transfer tube 11, the heat transfer performance of the heat transfer tube 11 is dominant on the inside (relatively small compared to the outside), and the heat transfer coefficient on the outside of the heat transfer tube 11 to the heat transfer performance is reduced. The effect is smaller. Therefore, it is only necessary that seawater flows down from the trough 3 to the outer surface 11a of the heat transfer tube 11 even slightly. Normally, when the flow rate of the seawater from the trough 3 is much lower than the minimum flow rate, the liquid film is cut off on the outer surface 11a of the heat transfer tube 11. Therefore, in the configuration in which part of the seawater sent to the trough 3 via the trough supply pipe 6 is sent to the sparge pipe 4 via the intermediate supply pipe 7 as described above, the maximum flow rate of seawater from the trough 3 is 10 times. Supply to the sparge pipe 4 is possible up to a flow rate of about 30%.

  In the vaporizer 1 of the above embodiment, the intermediate supply unit is a tubular member arranged along the heat transfer tube panel 2 so as to extend in the direction in which the plurality of heat transfer tubes 11 are arranged. Is formed by a sparge pipe 4 having a plurality of supply ports 4a for supplying additional seawater W2 toward the outer surface 11a of the sparge. Therefore, additional seawater W2 can be dispersed and supplied from the plurality of supply ports 4a to the outer surface 11a of each heat transfer tube 11, and air entrainment of the liquid film flow W1 can be performed using a small amount of additional seawater W2. It is possible to reliably suppress it.

  As shown in FIG. 8A, when the heat transfer tube 11 has a configuration including a plurality of fins 11 c protruding outward from the outer peripheral surface of the main body 11 b, the sparge tube 4 is a heat transfer tube. The additional seawater W2 is supplied from the supply port 4a to a range including an area 11d sandwiched between the fin 11c provided at a position closest to the sparge pipe on the outer surface 11a of the eleventh and the fin 11c adjacent thereto. Is preferred.

  Using the sparge pipe 4, the fin 11 c provided at a position closest to the sparge pipe 4 on the outer surface 11 a of the heat transfer pipe 11 from the supply port 4 a (that is, the fin denoted by reference numeral 11 cN) and the fin adjacent thereto The additional seawater W2 is supplied to a range including a region 11d sandwiched between the seawater W2 and the seawater W2. Thus, the additional seawater W2 supplied to the area 11d flows on the peripheral surface of the heat transfer tube 11 from a position close to the sparge pipe 4 to a position far from the sparge tube 4, so that the additional seawater W2 can be applied to the other fins 11c. become. As a result, it is possible to improve the effect of suppressing the entrapment of air in the liquid film flow W1 by the additional seawater W2. Further, in this case, the additional seawater W2 flows on the peripheral surface of the heat transfer tube 11 from a position close to the sparge tube 4 to a position far from the sparge tube 4, so that the tubular member is arranged close to the heat transfer tube 11 without impairing the air entrainment effect. It becomes possible. Further, the additional seawater W2 flows on the peripheral surface of the heat transfer tube 11 from a position close to the sparge tube 4 to a position far from the sparge tube 4, thereby suppressing the scattering of the liquid film flow W1 when the additional seawater W2 joins the liquid film flow W1. It becomes possible.

  On the other hand, as a comparative example, as shown in FIG. 8B, the supply port 4a is directed toward a fin 11c (ie, a fin denoted by reference numeral 11cF) on the outer surface 11a of the heat transfer tube 11 far from the sparge tube 4. When the additional seawater W2 is supplied from the fin 11cF, the additional seawater W2 impinging on the fin 11cF is scattered only on the surface of the fin 11cF, and the additional seawater W2 is sparged as shown in FIG. 8A. It cannot flow toward the fin 11c near the pipe 4. Therefore, the effect of suppressing air entrainment as shown in FIG. 8A and other effects cannot be obtained.

  In the above-described embodiment, an example in which a tubular member such as a sparge pipe 4 is provided as an intermediate supply unit has been described. However, the present invention is not limited to this. Various types of intermediate supply units may be employed as long as the additional heating liquid can be supplied toward the liquid (seawater or the like).

  For example, as in the modified example shown in FIGS. 9 to 10, a sub trough 16 may be employed instead of the sparge pipe 4 as the intermediate supply unit. The sub trough 16 is a gutter-shaped member having an opening on the upper surface, similar to the trough 3, and is smaller than the trough 3. The sub troughs 16 are arranged along the heat transfer tube panel 2 so as to extend in the direction in which the plurality of heat transfer tubes 11 are arranged. By flowing additional seawater W2 along the outer surface 11a of each heat transfer tube 11, the sub-trough 16 flows through the liquid film. The additional seawater W2 is merged with W1. The sub trough 16 communicates with the trough supply pipe 6 via the intermediate supply pipe 7.

  By flowing additional seawater W2 along the outer surface 11a of each heat transfer tube 11 along the liquid film flow W1 from the sub trough forming the sub trough 16, the liquid film flow W1 on the outer surface 11a of each heat transfer tube 11 Thus, the additional seawater W2 can be surely merged.

  The flow rate of the sub trough 16 is set to be smaller than the flow rate of the trough 3, and is set to, for example, about 10 to 30% of the flow rate of the trough 3.

  As described above, the sparge pipe 4 (see FIG. 1) and the sub trough 16 (see FIG. 9) constituting the intermediate supply section communicate with the trough supply pipe 6 via the intermediate supply pipe 7. It is not limited to the configuration. That is, as shown in FIGS. 11 to 12, the sparge pipe 4 and the sub trough 16 constituting the intermediate supply section may be connected to the middle of the bypass line 8 via the intermediate supply pipe 17.

  As another modified example of the present invention, the intermediate supply pipe 17 shown in FIGS. 11 to 12 has one end connected to the middle of the bypass line 8 and the other end connected to the sparge pipe 4 or the sub trough 16. Specifically, the intermediate supply pipe 17 is connected between the first part 17a, one end of which is connected to the bypass line 8 via the bypass valve 18, and the other end of the first part 17a and the sparge pipe 4 or the sub trough 16. And a second portion 17b to be connected.

  In the configuration shown in FIGS. 11 to 12, part of the seawater returned to the sea (that is, the supply source of seawater) via the bypass line 8 is connected to the sparge pipe 4 or the sparge pipe 4 forming the intermediate supply unit via the intermediate supply pipe 17. It can be sent to the sub trough 16. Therefore, it is possible to prevent the entrainment of air in the liquid film flow W1 by the additional seawater W2 supplied from the sparge pipe 4 or the sub trough 16 without increasing the pump power, thereby improving the heat transfer performance of seawater. Is possible. Moreover, in this configuration, the flow rate of seawater sent from the pump 5 to the trough 3 via the trough supply pipe 6 is not reduced by the seawater sent to the sparge pipe 4 or the sub-trough 16 via the bypass line 8, so that the trough 3 The heat transfer performance of the seawater flowing down to the heat transfer tube 11 does not decrease.

Reference Signs List 1 vaporizer 2 heat transfer tube panel 3 trough 4 sparge pipe (intermediate supply section)
Reference Signs List 5 pump 6 trough supply pipe 7, 17 intermediate supply pipe 8 bypass line 11 heat transfer pipe 16 sub trough (intermediate supply section)

Claims (11)

A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough and joins the additional heating liquid to the liquid film flow ,
The intermediate supply unit joins the additional heating liquid to the liquid film flow in a height range of the heat transfer tube where the liquid film flow and the air entrainment flow repeatedly occur.
Vaporizer. A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit may further include an additional heating unit for the liquid film flow in a height range of the heat transfer tube in which a heat transfer coefficient of the heating liquid is reduced due to air entrainment of the liquid film flow. Merge liquids,
Vaporization equipment. A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit merges the additional heating liquid with the liquid film flow in a range of a height equal to or less than half of the total height of the heat transfer tube,
Vaporization equipment. A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit supplies the additional heating liquid to the liquid film flow such that an inflow angle θ at which the additional heating liquid flows into the liquid film flow is 0 <θ ≦ 60 °. Merge,
Vaporization equipment. A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit has an outflow speed U when the additional heating liquid flows out of the intermediate supply unit,

(Where θ ₁ is the angle with respect to the horizontal plane when the additional heating liquid flows out of the intermediate supply unit, L is the horizontal movement distance of the additional heating liquid from the intermediate supply unit to the liquid film flow, and g is the gravity Acceleration)
Converging the additional heating liquid to the liquid film flow,
Vaporization equipment. A trough supply pipe connected to the trough,
A pump for sending the heating liquid to the trough through the trough supply pipe;
An intermediate supply pipe having one end connected to the middle of the trough supply pipe and the other end connected to the intermediate supply unit;
Further comprising
The vaporizer according to any one of claims 1 to 5 . A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
A trough supply pipe connected to the trough,
A pump for sending the heating liquid to the trough through the trough supply pipe;
A bypass line for returning a part of the heating liquid discharged from the pump to a supply source of the heating liquid,
An intermediate supply pipe having one end connected to the middle of the bypass line and the other end connected to the intermediate supply unit;
Further comprising
Vaporization equipment. A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit is a tubular member arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged, and the additional member is provided on a peripheral surface thereof toward an outer surface of each heat transfer tube. A tubular member having a plurality of supply ports for supplying a heating liquid,
Vaporization equipment. The heat transfer tube includes a tubular main body in which a passage through which the liquefied gas passes is provided, and a plurality of fins protruding outward from an outer peripheral surface of the main body.
The additional heating is performed from the supply port toward a range including a region sandwiched between a fin provided at a position closest to the tubular member and a fin adjacent thereto on the outer surface of the heat transfer tube. Supply liquid for
A vaporizer according to claim 8 . The intermediate supply unit is arranged along the heat transfer tube panel so as to extend in a direction in which the plurality of heat transfer tubes are arranged, and by causing the additional heating liquid to flow down along the outer surface of each heat transfer tube, Comprising a sub trough for joining the additional heating liquid to the liquid film flow,
The vaporizer according to any one of claims 1 to 7 . A vaporizer that vaporizes the liquefied gas by performing heat exchange between the liquefied gas and a heating liquid higher in temperature than the liquefied gas,
A heat transfer tube panel configured with a plurality of heat transfer tubes into which the liquefied gas is introduced and arranged side by side,
The plurality of heat transfer tubes are arranged along the heat transfer tube panel so as to extend in the direction in which the heat transfer tubes are arranged, and the heating liquid continuously flows down along the outer surface of each heat transfer tube, whereby the outer surface of the heat transfer tube A trough forming a liquid film flow by the heating liquid,
An intermediate supply unit that supplies an additional heating liquid toward the heating liquid flowing down from the trough, and merges the additional heating liquid with the liquid film flow.
With
The intermediate supply unit joins the additional heating liquid having a flow rate lower than the flow rate of the liquid film flow to the liquid film flow.
Vaporization equipment.