JP2013230091A - Method for alga culture, apparatus for alga culture, liquid for alga culture and production method thereof, and method for microalga culture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for culturing alga by effectively utilizing plating waste fluid, an apparatus for alga culture, a liquid for alga culture and a production method thereof, and a method for microalga culture.SOLUTION: There are provided methods for effective alga culture in a reduced cost including alga culture using a plating waste fluid containing a phosphorous component or organic acid component or both components among plating waste fluids, or alga culture using liquid containing a phosphorous component or organic acid component or both components derived from the plating waste fluid, consequently, the plating waste fluid can be effectively used, and reduces time and cost required for treatment of plating waste fluids.

Description

  The present invention relates to an algae culture method, an algae culture apparatus, an algae culture solution and a production method thereof, and a microalgae culture method using a plating waste solution such as electroless nickel plating.

  In recent years, attention has been focused on efforts to cultivate algae and use the collected algae as a new energy source. As a method for culturing algae, for example, a method of culturing algae in a dedicated liquid medium (culture solution) is generally used (see Patent Document 1).

Japanese Unexamined Patent Publication No. 7-75555

  In the conventional algae culture method, since a liquid medium adjusted to a predetermined composition is prepared, it takes time and cost.

  Therefore, the present invention provides a mechanism for culturing algae using the plating waste solution effectively.

  The algal culture method of the present invention is characterized by culturing algae using a plating waste solution having a phosphorus component, an organic acid component, or both.

  The present invention is also applicable to a method for culturing microalgae that produces hydrocarbons, characterized in that the above algal culture method is used for culturing microalgae that produce hydrocarbons.

  Furthermore, the algal culture apparatus according to the present invention includes a culture tank that contains a plating waste solution having a phosphorus component or an organic acid component, or both, and a supply unit that supplies the algae into the culture tank. The algae are cultured in a liquid containing the plating waste liquid.

  Moreover, the algal culture solution which concerns on this invention contains the plating waste liquid which has a phosphorus component or an organic acid component, or both at least.

  Furthermore, the algal culture solution according to the present invention is characterized by containing at least a phosphorus component or an organic acid component derived from the plating waste solution recovered from the plating waste solution, or both.

  The present invention also includes a method for producing an algae culture solution characterized in that a liquid containing at least a phosphorus component or an organic acid component or both is obtained by reducing the amount of heavy metal components from the plating waste solution. It is.

  According to the present invention, algae can be effectively cultivated by effectively utilizing the plating waste liquid, and in particular, by reusing the phosphorus component and organic acid component in the waste liquid as nutrient sources for the algae. Therefore, it is possible to reduce time and effort for preparing the culture solution of algae, and to reduce costs.

The schematic block diagram which shows an example of the algae culture apparatus which concerns on one Embodiment of this invention.

Hereinafter, an exemplary embodiment of the present invention will be described in detail.
The present invention uses a plating waste liquid having a phosphorus component or an organic acid component, or both of the plating waste liquid, or algae using a liquid containing a phosphorus component or an organic component derived from the plating waste liquid, or both. It is in the point to culture. In particular, the present invention focuses on the phosphorus component or the organic acid component contained in the plating waste liquid, and each of these components is utilized as a nutrient component in the culture of algae. Thereby, the effort which prepares the culture solution of algae can be reduced and cost reduction can be aimed at. In addition, according to the present invention, the plating waste liquid having a high environmental load can be effectively used, so that the capital investment required for processing for disposal as industrial waste and the cost of the processing agent can be reduced. In the first place, since the plating waste liquid has a high environmental load, it is necessary to perform a process for reducing the environmental load by using dedicated processing equipment and various processing agents. For example, in the conventional electroless nickel plating waste liquid treatment, it is necessary to secure equipment costs, operating costs, and equipment locations for providing equipment for recovering nickel and equipment for recovering phosphorus, respectively. According to the present invention, by using at least a part of the plating waste liquid to be treated for the plating waste liquid for algae culture, not only the plating treatment load can be reduced, but also the plating waste liquid can be effectively used.

  Here, if algae such as Botryococcus brownie that produces hydrocarbons is cultured, it can be effectively used as a raw material for natural energy conversion using algae. Examples of algae include unicellular algae or microalgae (particularly algae having a relatively small size). Furthermore, the present invention is suitable for culturing algae using a phosphorus component or an organic acid component, or both as nutrients, with or without photosynthesis, for example, Botryococcus brownie, Euglena, Algae that produce hydrocarbons such as auranthiochytrium can also be suitably used. Algae such as chlorella that can grow regardless of photosynthesis are also suitable for culturing.

  Here, the plating waste solution may be used as it is as a culture solution, but it is preferable to use a solution after reducing or removing heavy metal components. Further, as the plating waste liquid, it is preferable to use an electroless nickel plating waste liquid containing a phosphorus component and an organic acid component. In addition, when an electroless nickel plating waste solution is used as an algae culture solution, it may be used as it is, but a process for recovering a heavy metal component (here, a nickel component), for example, a reduction process such as electrodialysis or an ion exchange method. Alternatively, it is particularly preferable to use the waste liquid after the removal. The reason for this is that in addition to being able to reuse by recovering heavy metal components such as nickel, the phosphorus component and / or organic acid component in the plating waste solution, or both components in the waste solution after treatment rather than in the waste solution after plating This is because the ratio of these components can be increased. Thus, if the plating waste liquid after removing a heavy metal component is used as a culture solution, the culture efficiency of algae can be improved.

  In addition, as said plating waste liquid, phosphorus components (phosphates, such as hypophosphorous acid, phosphorous acid, nickel phosphite, etc.) or organic acid components (citric acid, succinic acid, malic acid, lactic acid, acetic acid, etc.) In addition, it is possible to use a plating waste solution containing at least one component selected from the group consisting of nitrogen (such as ammonia), inorganic salts, and sulfuric acid.

  Here, as the plating waste liquid, it is preferable to use the plating waste liquid repeatedly used in the plating treatment. This is because the plating waste liquid after repeatedly performing the plating treatment has a relatively high concentration of phosphorus components and organic acid components that are nutrient components of algae. Specifically, as the plating waste liquid, it is preferable to use a plating waste liquid of one turn or more that has been subjected to repeated plating treatment by replenishing the phosphorus component or the organic acid component or both according to the progress of the number of turns. It is effective to use plating waste liquid of preferably 3 turns or more, more preferably 5 turns or more.

  Table 1 below shows the component content for each turn per 1 liter of electroless nickel plating solution. Here, “turn” is an index for knowing the aging condition of a continuous type plating solution. For example, in Table 1 below, all the nickel contained in the bath during bathing (theoretical) is used. The time of use is represented as one turn. As shown in Table 1 below, as the number of turns increases, the content of each component of sulfate ion, phosphite ion, and each of the organic acids A to C contained in 1 liter of plating solution (waste solution) increases. . That is, it can be seen that a plating solution having a larger number of turns has more nutritional components as an algae culture solution and is very advantageous in culturing algae. Here, as shown in Table 1 below, the plating solution having a large number of turns has a phosphite ion content higher than a hypophosphite ion content and a sulfate ion content of hypophosphorous acid. It turns out that there is more than content. The phosphite ions include those in which at least a part of hypophosphite ions has changed with the plating treatment. Since the plating solution having a larger number of turns has more nutrient components of algae, if this is used as a culture solution, the culture efficiency of algae can be increased. If the plating waste solution is used as a culture solution as it is, the nutrient component has a high concentration. Therefore, it is preferable to use a culture solution that has been diluted 100 to 1000 times with dilution water such as water or tap water.

<Table 1> Main composition examples of electroless nickel plating solution

  Moreover, in this invention, it is preferable to use the plating waste liquid containing the additive containing nitrogen or an inorganic salt, or both components as a plating waste liquid. When components such as nitrogen components and inorganic salts are added in the plating process, the plating waste solution may be used as it is, or if the components such as nitrogen components and inorganic salts are insufficient in the plating waste solution. Can be separately added as an additive to obtain the algal culture solution of the present invention. Thereby, the culture efficiency of algae can further be improved.

  Here, in the present invention, a protozoan that proliferates while performing photosynthesis by selecting algae that can use nutrients as components contained in the plating waste liquid and preparing a culture environment suitable for photosynthesis in the plating waste liquid. Can also be cultured.

  When cultivating algae and protozoa for photosynthesis, install LED lighting, metal halald lamp, high pressure sodium lamp, white fluorescent lamp, incandescent lamp, etc. in the upper and lower parts of the culture tank, respectively. Coupled with the stirring mechanism, light can be irradiated on the algae and the whole protists in the culture tank. In addition, the depth of the culture tank at that time is preferably within a range where light can be appropriately transmitted to algae on the bottom side of the culture tank, for example, but a stirring mechanism or the like may be provided if necessary. However, the present invention is not limited to this. In addition, assuming that plants perform respiration and photosynthesis alternately, the light irradiation time may be adjusted as appropriate. In addition, such a culture apparatus has equipment for appropriately supplying outside air (air), carbon dioxide and the like as one of the culture environment conditions.

  In addition, the algae culture method of the present invention as described above includes, for example, a tank that stores a plating waste solution having a phosphorus component or an organic acid component, or both, a culture tank that includes a stirring mechanism for culturing algae, The apparatus can be efficiently implemented by an algae culture apparatus that includes a supply means for supplying the plating waste liquid and the algae in the culture tank and that cultures the algae using the plating waste liquid in the culture tank.

  Here, with reference to FIG. 1, an embodiment of the algal culture apparatus of the present invention will be described. FIG. 1 is a schematic configuration diagram showing an example of an algal culture apparatus according to the present invention.

  As shown in FIG. 1, in the algal culture apparatus 1 of the present embodiment, a waste liquid storage tank 11 and a diluent storage tank 12 are connected to an algal culture tank 13 via individual pipes 11a and 12a, respectively. In addition, filter devices 11b and 12b for removing impurities and the like are disposed in the pipes 11a and 12a that connect the waste liquid storage tank 11 and the diluent storage tank 12 and the culture tank 13, respectively. Although not shown, the culture tank 13 is provided with an inlet through which algae can be appropriately introduced from the outside. Further, a nozzle 14 for taking in outside air (air) and a discharge pipe 15 for discharging the culture solution from the inside of the culture tank 13 are connected to the bottom side of the culture tank 13. Note that an algae recovery device (for example, a filtration device) 17 is connected to the discharge pipe 15 via a valve 16, and the culture solution that has been recovered from the algae is returned to the culture tank 14 via the recovery device 17. A return circulation pipe 18 is connected. In addition, each piping 11a, 12a, 15, 18 mentioned above is connected with the pump for liquid feeding, respectively, and the flow volume is controllable. The algae cultured in the culture tank 13 may be collected directly from the culture tank 13 or may be collected from the collection device 17. In the former case, the collection device 17 plays a role of collecting the algae remaining at the time of collection from the culture tank 13.

  In the algae culture apparatus 1 having such a configuration, a predetermined plating waste liquid (high concentration stock solution) is placed in the waste liquid storage tank 11, and the high concentration plating waste liquid is placed in the culture tank 13 together with a diluent (for example, water). Supply. In the culture tank 13, the high-concentration plating waste liquid is adjusted to have a predetermined concentration with dilution water, and in this state, algae is introduced and air is appropriately supplied from the nozzle 14 to culture the algae. It has become. In addition, a stirring means may be provided in the culture tank 13 and the tank may be stirred as necessary. The dilution water may be pure water or tap water. In addition, the culture solution after draining the cultured solution from the culture vessel 13 is returned to the culture vessel 13 again through the algae recovery device 17, but the plating waste solution and dilution water are used for the next cultivation. An appropriate amount is supplied to prepare the culture solution in the culture tank 13. In such a blending process, the plating waste liquid or the like is controlled by controlling the driving of each pump for liquid feeding by a control unit (not shown) so as to adjust the nutrient components of the algae in the culture tank 13 to a predetermined amount. Each supply amount and discharge amount are adjusted.

  In addition, although the algal culture apparatus 1 of this embodiment provided the insertion port into which the algae is input, the present invention is not limited to this, for example, a means for automatically supplying the algae to the culture tank is connected. May be. Moreover, although the example which provided the culture tank 13 of one algae is demonstrated in FIG. 1, when providing the culture tank 13 with two or more, what is necessary is just to be able to supply a plating waste liquid and dilution water to each culture tank. . Furthermore, a storage tank for temporarily storing the solution after algae recovery may be provided in a circulation pipe (pipe) 18 that connects the algae recovery device 17 and the culture tank 13. In any case, the present invention is not limited to the specific configuration of the algae culture apparatus 1 described above.

  Here, this invention is applicable also to the algal culture solution which contains the plating waste liquid which has a phosphorus component or an organic acid component, or both. Such an algal culture solution of the present invention can be realized by using only the plating waste solution, but may be appropriately diluted with water or the like, and in order to further promote the culture of algae, nitrogen components (nitric acid, nitrate, ammonia) Etc.) and components suitable for culturing algae such as inorganic salts (potassium sulfate, potassium nitrate, etc.) are more preferably adjusted and mixed.

  By the way, there are two methods for depositing a metal from an aqueous solution containing metal ions: an electroplating method using an external current and an electroless plating method that does not require the action of electricity, and the latter involves chemical reduction. There are chemical plating methods used. In the chemical plating method, for example, a metal film can be formed on a solid surface with metals including nickel, cobalt, silver, gold, copper, and high alloy steel. In particular, electroless nickel plating has high corrosion resistance, high hardness, and high gloss, so it can be used for surface treatment of all metal materials such as electronic parts, home appliances, automobile parts, chemical equipment, industrial equipment, plastics, ceramics, etc. Has been.

  Electroless nickel plating waste liquid contains nickel salts, inorganic phosphorus components such as hypophosphorous acid as a chemical reducing agent and phosphorous acid as its oxide, complex for preventing precipitation of nickel hydroxide and nickel phosphite. Organic additives such as organic acids are included as an agent and a pH buffer, and sulfuric acid, sodium hydroxide, ammonia and the like are further included as a pH adjuster.

  Here, as a method for recovering nickel from such electroless nickel plating waste liquid, electrodialysis, ion exchange method, solvent extraction method, displacement precipitation method, etc., in which nickel ions are taken in and recovered by an anion exchange membrane, etc. is there. By these methods, the waste liquid from which the nickel component is selectively removed from the electroless nickel plating waste liquid, that is, one algae culture solution according to the present invention can be efficiently produced.

  As a method for recovering phosphorus, hypophosphite ions are reacted with hydrogen peroxide under ultraviolet irradiation, oxidized to normal phosphate ions, and then removed from the waste liquid as insoluble salts. Hypophosphite Is treated with persulfate to form phosphorous acid or orthophosphoric acid, and is treated as an insoluble salt from the waste liquid. Nickel phosphite or a metal compound other than nickel is used as a catalyst to convert hypophosphorous acid to phosphorous acid. After oxidation to an acid, a method of removing it from waste liquid as an insoluble salt after oxidation to orthophosphoric acid with a hypochlorous acid oxidizing agent can be used. Thereby, a phosphorus component can be selectively extracted from the plating waste liquid, and the phosphorus component derived from such a plating waste liquid can be effectively reused as an algae culture component. That is, the phosphorus component derived from the plating waste solution may be used as the culture component as it is, or the phosphorus component derived from the plating waste solution is added as an additive for the algae culture solution to the existing culture solution to obtain the algae culture solution of the present invention. It is also possible. That is, the present invention also includes a culture component composed of a phosphorus component derived from a plating waste solution, or an algal culture solution additive containing such a culture component. In addition, if the phosphorus component derived from the plating waste liquid (culture component extracted from the plating waste liquid) is added to the plating waste liquid, and the waste liquid in which the concentration of the phosphorus component in the plating waste liquid is adjusted to a high concentration is used as the algae culture liquid, Algal culture efficiency can be increased. The “phosphorus component or organic acid component derived from the plating waste liquid” indicates a phosphorus component or organic acid component recovered from the plating waste liquid, and includes a case where the component of the plating waste liquid is contained therein.

  Here, in the above-described embodiment, the structure for supplying the plating waste solution and the dilution water to the culture tank has been described as the algae culture device, but the present invention is not limited to this. For example, the above-described phosphorus component recovery unit having the function of recovering the phosphorus component, organic acid component recovery unit having the function of recovering the organic acid component, or each component recovered by each of these recovery units is supplied to the culture tank By providing an active ingredient supply part or an additive supply part that supplies various additives, and providing an adjustment function (adjustment part) that adjusts each supply amount together with the supply of plating waste liquid and dilution water, the nutrient concentration of algae Can be achieved.

DESCRIPTION OF SYMBOLS 1 Algae culture apparatus 11 Waste liquid storage tank 12 Dilution liquid storage tank 13 Culture tank 14 Nozzle 15 Discharge piping 16 Valve 17 Recovery apparatus 18 Circulation piping 19 Filter apparatus

Claims (15)

  An algae culture method comprising culturing algae using a plating waste solution having a phosphorus component, an organic acid component, or both.   The algae culture method according to claim 1, wherein an electroless nickel plating waste liquid is used as the plating waste liquid.   The algae culture method according to claim 1 or 2, wherein a plating waste liquid after reducing the amount of heavy metal components is used as the plating waste liquid.   The algae culture method according to any one of claims 1 to 3, wherein a plating waste liquid repeatedly used in the plating treatment is used as the plating waste liquid.   The plating waste liquid is a one-turn or more plating waste liquid that is repeatedly subjected to plating treatment by replenishing a phosphorus component or an organic acid component or both according to the progress of the number of turns. 4. The algae culture method according to any one of 3 above.   The algae culture method according to any one of claims 1 to 5, wherein a plating waste solution containing an additive containing nitrogen or inorganic salts or both components is used as the plating waste solution.   The algae culture according to any one of claims 1 to 6, wherein a plating waste liquid containing at least one component selected from the group consisting of nitrogen, inorganic salts, sulfuric acid, and sodium is used as the plating waste liquid. Method.   The algae culture method according to any one of claims 1 to 6, wherein a plating waste liquid in which a content of phosphite ions is higher than a content of hypophosphite ions is used as the plating waste liquid.   The algae culture method according to any one of claims 1 to 6, wherein a plating waste liquid having a sulfate ion content higher than a hypophosphorous acid content is used as the plating waste liquid.   The algae culture method according to any one of claims 1 to 9, wherein a protozoan to be photosynthesized is placed in a solution containing the plating waste solution and cultured.   A method for culturing microalgae that produces hydrocarbons, wherein the method for culturing algae according to any one of claims 1 to 9 is used for culturing microalgae that produce hydrocarbons.   A culture vessel containing a plating waste solution containing a phosphorus component or an organic acid component, or both; and a supply means for supplying algae into the culture vessel, wherein the algae is contained in a solution containing the plating waste solution in the culture vessel. An algal culture apparatus characterized by culturing.   An algae culture solution comprising at least a plating waste solution having a phosphorus component, an organic acid component, or both.   An algae culture solution containing at least a phosphorus component, an organic acid component, or both derived from a plating waste solution recovered from a plating waste solution. A method for producing an algae culture solution, wherein a solution containing at least a phosphorus component, an organic acid component, or both is obtained by reducing the amount of a heavy metal component from a plating waste solution.

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