JP4459752B2 - Method for producing nutrient salt reference material and production apparatus used therefor - Google Patents

Description

  The present invention relates to a method for producing a nutrient salt reference material and a production apparatus used therefor, and more specifically, a method for producing a nutrient salt reference material that serves as an index when measuring the nutrient salt concentration of seawater as a sample, and the method thereof The present invention relates to an apparatus used for the method.

As is well known, it is speculated that approximately 9 billion tons of carbon is exchanged as CO ₂ gas annually between the surface layer of the atmosphere and the ocean, but the CO ₂ partial pressure of the ocean surface layer is CO _2. whereas _{the 2} partial pressure is increased in welling riser mixing high deep seawater decreases with use, etc. of inorganic carbon by photosynthesis phytoplankton. Thus, CO ₂ is consumed by photosynthesis of phytoplankton and organic matter is generated. On the other hand, as an energy source for phytoplankton to perform photosynthesis, nitrate, nitrite, phosphate, silicate, and Nutrient salts that are salts such as ammonium salt are required.

  Therefore, in the marine survey, measurement of the above-mentioned nutrients that are closely related to biological activities has been carried out in order to find changes in the global environment centering on global warming. In this measurement, it is an essential item to measure the concentration of nutrients. In this case, a nutrient reference material that can be used as an index when comparing measurement data on nutrients in different seawater samples is manufactured and used. It is important to use it.

  In order to respond to such a request, according to the following Patent Document 1, a plurality of types of raw material seawater filtration processing steps with different nutrient concentrations collected from different water depths in a predetermined sea area, and the raw material seawater at a predetermined ratio. A method for producing a nutrient reference material having a mixing treatment step for mixing and a sterilization treatment step for killing microorganisms in raw seawater is disclosed.

  In this case, including the case where the manufacturing method disclosed in the above-mentioned Patent Document 1 is carried out, the conventional apparatus used for manufacturing a nutrient reference material is a large-capacity container capable of storing a predetermined amount of seawater. It is configured to sterilize by heating seawater (raw seawater) containing nutrient salt in this large capacity container, but the inner surface of this large capacity container is pickled without being polished. It was a surface that had been polished or buffed.

JP 2003-214996 A

  However, if the inner surface is only pickled or buffed like the large-capacity container used for the production of the above-mentioned conventional nutrient salt reference material, the surface roughness Rz of the inner surface is large. Then, a situation occurs in which a nutrient salt composed of silicate or phosphate adheres to the inner surface of the container after sterilization. For this reason, the concentration of the nutrient salt in the nutrient salt reference material, which is seawater after sterilization, is reduced, and a nutrient salt reference material with a uniform concentration cannot be obtained over the entire area of the large-capacity container, resulting in a deterioration in quality. Will be invited.

  Furthermore, after storing seawater in the above-mentioned large-capacity container and performing sterilization treatment by heating, the temperature of the large-capacity container was lowered to room temperature and held until the seawater (nutrient reference substance) was taken out. In this case, water vapor adheres to the inner surface of the upper lid of the container, and when seawater is taken out as a nutrient salt reference material, the water vapor is mixed therein, and the concentration of the nutrient salt partially decreases. Therefore, even in this case, a nutrient reference substance having a uniform concentration cannot be obtained, resulting in deterioration of quality.

  The present invention has been made in view of the above circumstances, and avoids a situation in which the nutrient salt concentration of seawater (nutrient reference material) after sterilization in a large-capacity container is unduly lowered and has a uniform concentration. A technical issue is to obtain a nutrient reference substance.

  The method according to the present invention, which has been made to solve the above technical problem, is a method in which seawater containing nutrient salts is subjected to sterilization treatment including at least heat treatment in a state where the seawater is stored in a large-capacity container. A method for producing a nutrient reference substance that serves as an index for measuring the nutrient concentration of a seawater sample by distributing and pouring the sterilized seawater into a plurality of small-capacity bottles from the large-capacity container. The sterilization treatment is performed in a state in which seawater containing nutrient salts is stored in a large-capacity container made of metal and having an inner surface electropolished.

  In this case, the large-capacity container is preferably made of stainless steel, and is preferably capable of storing 100 to 1000 liters (appropriate value is 200 liters) of seawater to be a nutrient reference material. Moreover, it is preferable that the said small capacity | capacitance bottle is poured into 50 milliliters-200 milliliters (appropriate value is 100 milliliters). Therefore, it is preferable that the nutrient reference substance is distributed and supplied from a single large-capacity container to 1000 to 3000 (2000 as an appropriate value) small-capacity bottles. The sterilization treatment is performed under conditions of high temperature and high pressure with a heat treatment of about 100 ° C. to 150 ° C., preferably about 120 ° C., and a pressure treatment of about 0.1 to 0.2 MPa, preferably about 0.12 MPa. It is preferable to be performed at Further, the electrolytic polishing finish includes a case where electrolytic polishing is performed after buff polishing, and in any case, it means that the inner surface finishing method is electrolytic polishing. Further, the nutrient reference substance is a substance whose nutrient salt concentration is stable for a long time at room temperature in a sealed state.

  According to such a method, since the inner surface (preferably the entire inner surface) of the large-capacity container for storing seawater as a raw material for the nutrient reference material is subjected to electrolytic polishing finish, conventional pickling finish or buff polish finish As compared with the case of the above, the surface roughness Rz of the inner surface can be greatly reduced. In this case, the surface roughness Rz of the inner surface obtained by electropolishing is, for example, 1.5 μm or less, preferably 0.7 μm or less. Thus, if the surface roughness Rz of the inner surface of the large-capacity container is reduced, phosphate or silicate adheres to the inner surface of the large-capacity container when seawater to be a nutrient reference material is sterilized. The situation is avoided as much as possible, and it is possible to suppress a decrease in the concentration of the nutrient reference material (nutrient concentration), and the nutrient reference material with a uniform concentration throughout the large-capacity container Can be obtained. As a result, the nutrient reference substance having a uniform concentration can be bottling all over the plurality of small-capacity bottles.

  In the above method, after sterilization, the temperature of the large-capacity container is lowered to room temperature, and then the large-capacity container is shaken so that water vapor adhering to the inner surface of the upper part of the container is mixed in the seawater and stirred. It is preferable.

  In this way, the water vapor adhering to the inner surface of the upper part of the container accompanying the temperature drop of the large capacity container (decrease from the range of 23 ° C. to 24 ° C.) is shaken by swinging the large capacity container, etc. Since it will be mixed and stirred in the seawater stored in the inside, the density | concentration nonuniformity resulting from water vapor | steam is suppressed. Therefore, from the initial stage to the late stage of the bottling process, a uniform concentration of the nutrient reference material is poured into a plurality of small volume bottles in sequence, and the variation in the concentration of the nutrient reference material between each of the small volume bottles. Will not occur.

  In the above method, before the seawater that has been sterilized is distributed and poured from a large-capacity container into a plurality of small-capacity bottles, the sterilized seawater that has been sterilized inside the large-capacity container is stirred by a stirring means. Is preferred.

  In this way, since the seawater is stirred by the stirring means in the large capacity container before the bottling process is performed, the concentration of nutrients in the seawater in the entire area of the large capacity container becomes uniform, and a plurality of small volumes A more uniform concentration of the nutrient reference material will be poured into the bottle sequentially.

  On the other hand, an apparatus according to the present invention made to solve the above technical problem includes a large-capacity container that stores seawater containing nutrient salts, and heating that heats the seawater stored in the large-capacity container. An apparatus for producing a nutrient reference material that serves as an index when measuring the nutrient concentration of a seawater sample, wherein the large-capacity container is made of metal and the inner surface thereof is electropolished. It is characterized by being.

  According to such an apparatus, since the surface roughness Rz of the inner surface of the large-capacity container is electropolished to be smaller than that of the conventional one, the same effect as the manufacturing method described above can be obtained. It is done. It should be noted that the components common to the manufacturing method already described, such as the fact that a pressurizing means may be provided in addition to the heating means, the size of the large-capacity container, and the significance of electrolytic polishing, etc. The device has the same significance.

  In the above apparatus, the large-capacity container has a container main body having a large opening at the upper end, and a lid that has a small opening that can be opened and closed and covers the large opening, and the inner surface of the container main body and It is preferable that the inner surface of the lid body is electropolished.

  In this way, a large amount of seawater can be poured at once from the large opening at the upper end of the container body, and the nutrient reference substance is sequentially supplied to a plurality of small-capacity bottles through the small opening that can be opened and closed. The work efficiency can be improved. The advantages obtained by electropolishing the inner surface of the container main body and the inner surface of the lid are the same as those already described.

  In the above apparatus, the large-capacity container is preferably configured to be able to be shaken so that water vapor adhering to the inner surface of the upper part of the container is mixed in the seawater and stirred.

  In this way, the water vapor adhering to the inner surface of the upper portion of the container as the temperature of the large-capacity container is lowered is mixed and stirred in the seawater stored in the large-capacity container by shaking the large-capacity container. Therefore, the concentration non-uniformity caused by water vapor is suppressed, and it is possible to obtain the same effects as the matters already described correspondingly.

  As described above, according to the present invention, since the inner surface of the large-capacity container for storing seawater as a raw material for the nutrient reference substance is subjected to electrolytic polishing, it is compared with the case of conventional pickling finish or buff polishing finish. Thus, the surface roughness Rz of the inner surface can be significantly reduced. This avoids as much as possible the situation where phosphate and silicate adhere to the inner surface of the large-capacity container when sterilizing seawater that should serve as a nutrient reference material. It is possible to suppress the decrease, and to obtain a nutrient reference material with a uniform concentration over the entire area of the large-capacity container. A salt reference material could be bottling.

  Preferably, after sterilization, the large-capacity container is shaken with the temperature of the large-capacity container lowered to room temperature, and the seawater is agitated by stirring means before bottling (preferably before bottling to the end). Since it did in this way, since the water vapor | steam adhering to the inner surface of the container upper part will be mixed and stirred in the seawater stored in the inside, the nonuniformity of the density | concentration caused by water vapor | steam is suppressed. As a result, from the initial stage to the late stage of the bottling process, a uniform concentration of the nutrient reference substance can be poured into a plurality of small-capacity bottles sequentially, and the nutrient reference substance between each small-capacity bottle can be poured. There is no variation in density.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic front view showing an apparatus for producing a nutrient reference substance according to an embodiment of the present invention. As shown in the figure, the manufacturing apparatus 1 includes a large-capacity container 2 that stores about 200 liters of seawater (seawater containing nutrient salts) that is a raw material for a nutrient salt reference material. The large-capacity container 2 includes a container body 3 having a large opening 3 a at the upper end, and a lid 4 having a small opening 4 a on the upper surface and covering the large opening 3 a of the container body 3. . In this case, the large opening 3a at the upper end of the container body 3 serves as an inlet for introducing seawater as a raw material of the nutrient reference material with the lid 4 removed, and the small opening of the lid 4 The part 4a can be opened and closed by the opening / closing means 5, and serves as an outlet for taking out seawater (nutrient reference material) that is sterilized when it is opened.

  The inner surface 3x of the container body 3 and the inner surface 4x of the lid body 4 are electropolished, and the surface roughness Rz of both the inner surfaces 3x and 4x is 1.5 μm or less, preferably 0.7 μm or less, In this embodiment, the range is 0.03 μm to 0.5 μm. And this manufacturing apparatus 1 performs sterilization by performing the heat processing heated to about 120 degreeC with respect to the seawater stored in the large capacity | capacitance container 2, and the pressurization processing pressurized to about 0.12 MPa. A heating means and a pressurizing means for performing the treatment are provided.

  Further, the manufacturing apparatus 1 swings the large-capacity container 2 by swinging or moving up and down through shaft members 6 and 6 projecting radially at positions 180 ° apart from the outer periphery of the container body 3. A possible support structure 7 is provided. In this embodiment, the large-capacity container 2 is shaken manually. If necessary, the large capacity container 2 may be automatically shaken by the operation of the driving means. Further, inside the container main body 3 of the large-capacity container 2, a stirring means 9 made of a rotatable stirrer made of, for example, Teflon (registered trademark) is disposed.

  Next, a method for manufacturing a nutrient reference substance using the manufacturing apparatus 1 having the above-described configuration will be described.

  First, 200 liters of seawater sampled in a predetermined sea area is put into the container body 3 and heated (120 ° C.) and heated with the lid 4 covering the large opening 3a at the upper end of the container body 3. A sterilization treatment for killing microorganisms in seawater is performed by pressure (0.12 MPa). This heat treatment and pressure treatment are executed twice in order to ensure the treatment. In this case, the seawater contains nutrient salts composed of nitrate, nitrite, phosphate, silicate, and ammonium salt, but the inner surfaces 3x, 4x of the container body 3 and the lid 4 are Since the surface roughness Rz is reduced by the electrolytic polishing, the situation where phosphates and silicates adhere to the inner surfaces 3x and 4x is suppressed as much as possible, and an appropriate nutrient concentration is obtained. .

  Further, after the sterilization treatment for seawater, the large-capacity container 2 is kept at room temperature (23 ° C. to 24 ° C.), so that water vapor adheres to the inner surface of the upper portion of the container, in particular, the inner surface 4x of the lid 4. On the other hand, the large capacity container 2 is shaken and the seawater is stirred by the stirring means 9. Accordingly, the seawater is appropriately stirred over the entire area in a state where water vapor is mixed in the seawater, and as a result, the seawater in which the nutrient salt concentration is made uniform in the entire area within the large-capacity container 2, that is, the nutrient reference substance Is obtained.

  Thereafter, the small opening 4a of the lid 4 is opened, and a bottling process for sequentially pouring the nutrient reference material into a small-capacity bottle made of resin (for example, polypropylene) is executed. As a result, as shown in FIG. 2, 2000 small-capacity bottles 10 in which 100 milliliters of the nutrient reference material are enclosed are obtained. In this case, since the concentration (nutrient concentration) of the nutrient salt reference substance in the large-capacity container 2 is uniform throughout the container, all of the 2000 small-capacity bottles 10 have the same concentration of nutrition. A salt reference substance will be enclosed, and the dispersion | variation in the density | concentration between each small capacity | capacitance bottle 10 will be lose | eliminated.

  Furthermore, as shown in FIG. 3, these small-capacity bottles 10 are sealed by a vacuum suction seal 11 to be in a so-called vacuum packed state, and are supplied as products to the market. The nutrient salt reference material in the small-capacity bottle 10 is used by a user (researcher or the like) to measure the concentration of a seawater sample collected from the sea area to be investigated.

It is a schematic longitudinal front view which shows the manufacturing apparatus of the nutrient reference material which concerns on embodiment of this invention. It is the schematic which shows the several small capacity | capacitance bottle formed by sealing the nutrient reference material distributed from the manufacturing apparatus of the nutrient reference material which concerns on embodiment of this invention. It is the schematic which shows the state which sealed the several small capacity | capacitance bottle formed by sealing the nutrient reference material distributed from the manufacturing apparatus of the nutrient reference material which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nutrient salt reference substance manufacturing apparatus 2 Large-capacity container 3 Container body 3a Large opening 3x of container body 4 Inside surface of container body 4 Lid 4a Small opening 4x of lid body 7 Shaking means 10 Small capacity bottle

Claims (6)

Seawater containing nutrient salt is stored in a large-capacity container, and after sterilization including at least heat treatment, the sterilized seawater is discharged from the large-capacity container into a plurality of small-capacity bottles. A method for producing a nutrient reference material that serves as an index when measuring the nutrient concentration of a seawater sample by dispensing and dispensing
A method for producing a nutrient reference material, characterized in that the sterilization treatment is performed in a state in which seawater containing nutrient salts is stored in a large-capacity container made of metal and having an inner surface electropolished.   After the sterilization treatment, the temperature of the large-capacity container is lowered to room temperature, and then the large-capacity container is shaken so that water vapor adhering to the inner surface of the upper part of the container is mixed in seawater and stirred. A method for producing a nutrient salt reference material according to claim 1.   Before the seawater that has been sterilized is distributed and poured from a large-capacity container into a plurality of small-capacity bottles, the seawater that has been sterilized is stirred inside the large-capacity container by stirring means. The manufacturing method of the nutrient reference material of Claim 1 or 2. It has a large-capacity container for storing seawater containing nutrient salts and a heating means for heating the seawater stored in the large-capacity containers, and serves as an index when measuring the nutrient salt concentration of seawater samples An apparatus for producing a nutrient reference substance,
An apparatus for producing a nutrient salt reference material, wherein the large-capacity container is made of metal and the inner surface thereof is electropolished.   The large-capacity container has a container body having a large opening at an upper end, and a lid having a small opening that can be opened and closed and covering the large opening, and an inner surface of the container body and the lid 5. The apparatus for producing a nutrient salt reference material according to claim 4, wherein the inner surface is electropolished.   The said large capacity container is comprised so that the water vapor | steam adhering to the inner surface of the container upper part can be shake | mixed so that it may mix in seawater and may be stirred. Nutrient reference substance production equipment.

Images