九、發明說明： 【發明所屬之技術領域】 發明領域 本發明係一種有關鹼金屬碳酸鹽溶液之精製方法、精 製裝置及以該方法精製之驗金屬碳酸鹽溶液而該驗金屬 碳酸鹽係㈣於製造_材或木㈣存鮮補之驗性碳 酸銅等之碳酸納為主。 C 前好;J 發明背景 通常，鹼性碳酸銅（以下，稱為碳酸鋼)係作為鋼鍍材料 補給源之氧化銅或木材保存劑等之原料，而廣泛利用於工 業上。例如，碳酸銅可由氯化銅等無機銅鹽水溶液，與碳 酸鈉等驗金屬碳酸鹽水溶液反應製造。 目前已知的是’以驗金屬碳酸鹽製造碳酸銅時，一旦 於驗金屬碳酸鹽中含有例如鈣或鎂之化合物等不純物，則 幾乎其全量將混入碳酸銅。若以混有該等不純物之碳酸銅 作為銅錢材料使用時’則在電鍍過程中不純物將被濃縮並 析出於被鍍材料上，使電鐘精加工受到不良影響。另，作 為木材保存劑之原料使用時，則於木材保存劑之製造過程 中，該等不純物成為不溶解殘渣析出，造成製品之過濾步 驟等之負荷加重。 例如，工業兩碳酸鈉粉末中，含有數十〜100重量ppm 以上之鈣或鎂之化合物，該等含量會依製造方法或製造批 號等不同而改變，故希望有一種可從作為碳酸銅原料之鹼 金屬碳酸鹽，將該等不純物穩定地去除的技術β 對於此種需求’專利文獻1中記載一種技術，即於碳酸 鈉水溶液中’灌入二氧化碳氣體，使碳酸氫鈉或倍半碳酸 納成為固體析出，且使水溶液中之鈣離子吸附於該固體表 面以分離不純物。但在該方法中，為了要分離不純物，會 消耗製造碳酸銅等所需之原料的一部分，故在經濟上效率 不佳。 專利文獻1 :特公平6-21033號公報 C發明内容】 發明概要 本發明係鑑於前述事情而作成者，且本發明之目的在 於提供一種不會耗損鹼金屬碳酸鹽、並可低成本且簡便地 去除含於鹼金屬碳酸鹽中之鈣化合物的鹼金屬碳酸鹽之精 製方法、精製裝置及以該方法精製之驗金屬碳酸鹽溶液。 本發明之鹼金屬碳酸鹽溶液之精製方法，包含有： 一調製步驟’係對於含有由鈣化合物形成之不純物的 鹼金屬碳酸鹽，將鹼金屬碳酸鹽之濃度調製為15重量％以 上之鹼金屬碳酸鹽溶液者； 一析出步驟，係在使鹼金屬碳酸鹽不析出之狀態下， 保持該鹼金屬碳酸鹽溶液一定時間後，使溶解於鹼金屬碳 酸鹽溶液中之不純物析出者；及 一固液分離步驟，係使析击之不純物與鹼金屬碳酸鹽 溶液固液分離者。 該精製方法中，更以包含有一稀釋步驟，係以水稀釋 1331985 分離出前述析出之不純物後之鹼金屬碳酸鹽溶液，以製造 預定濃度之鹼金屬碳酸鹽溶液者為佳。或在析出步驟中， 以水稀釋前述不純物析出後之驗金屬竣酸鹽溶液（稀釋步 驟），接著使析出之不純物與鹼金屬碳酸鹽溶液固液分離（固 ' 5 液分離步驟)之構成亦可。 . 在前述調製步驟之鹼金屬碳酸鹽溶液的濃度，係以溶 解有相對於鹼金屬碳酸鹽之飽和溶解度為60%以上，且未 達飽和溶解度之鹼金屬碳酸鹽量的濃度為宜。另本精製方 ^ 法中，前述驗金屬碳酸鹽以碳酸納或碳酸钾為宜。 10 根據本發明相關之鹼金屬碳酸鹽溶液的製造方法，使 溶解於鹼金屬碳酸鹽溶液中之不純物的鈣化合物析出，而 可將其分離去除。因此，使水溶液中之鹼金屬碳酸鹽作為 固體析出，而使鈣離子等不純物吸附於該析出的固體上之 習知方法有異，故成為製品之鹼金屬碳酸鹽既無耗損，且 • 15 可經濟地，有效率地精製鹼金屬碳酸鹽溶液。另，本精製 方法中，由於可僅對鹼金屬碳酸鹽溶液邊進行溫度管理， • 並保持一定時間後，不純物就可析出，故例如該水溶液無 需與其他的物質進行反應等之特別步驟的必要。因此，用 以實施該方法之裝置構成或其他操作可簡化，可低成本且 20 簡便地精製鹼金屬碳酸鹽溶液。 ' 圖式簡單說明 /ris 1 Τ^Ί η口 p 曰 ττ/ ν —山 Αλ. Τ> 、·Λ- ·1 走 «φίΐ —X- *1. 乐丄固1乐s兄口月峒Γ剧貫把ττ，悲之吸S文鈉D谷狀稱裝刀法 之流程圖。 第2圖係顯示有關實施形態之碳酸鈉水溶液精製裝置 7 1331985 之一例之構成圖。 第3(a)、（b)圖係顯示用以確認本發明之效果所進行之 試驗結果之特性圖。 第4圖係顯示用以確認本發明之效果所進行之試驗結 5 果之特性圖。 【實施方式】 實施發明之最佳形態IX. INSTRUCTIONS OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for refining an alkali metal carbonate solution, a refining device, and a metal carbonate solution refined by the method, and the metal carbonate system (IV) The production of _ wood or wood (four) fresh and precious copper carbonate and other carbonated sodium. C. Background of the Invention In general, alkaline copper carbonate (hereinafter referred to as carbon steel) is widely used in industrial applications as a raw material for copper oxide or wood preservative for replenishing steel plating materials. For example, copper carbonate can be produced by reacting an aqueous solution of an inorganic copper salt such as copper chloride with an aqueous solution of a metal carbonate such as sodium carbonate. It is known that when copper carbonate is produced from a metal carbonate, once the metal carbonate contains an impurity such as a compound such as calcium or magnesium, almost the entire amount thereof is mixed with copper carbonate. If copper carbonate mixed with such impurities is used as a copper material, the impurities will be concentrated and deposited on the material to be plated during the electroplating process, which adversely affects the finishing of the electric clock. Further, when used as a raw material for a wood preservative, the impurities are precipitated as insoluble residues in the production process of the wood preservative, and the load such as the filtration step of the product is aggravated. For example, in the industrial sodium carbonate powder, a compound containing tens to 100 ppm by weight or more of calcium or magnesium is used, and the content may vary depending on the manufacturing method or the manufacturing lot number, etc., so it is desirable to have a material which can be used as a raw material of copper carbonate. Alkali metal carbonate, a technique for stably removing such impurities. For such a demand, Patent Document 1 describes a technique in which carbon dioxide gas is poured into an aqueous sodium carbonate solution to make sodium hydrogencarbonate or sodium sesquicarbonate A solid precipitates and calcium ions in the aqueous solution are adsorbed on the solid surface to separate the impurities. However, in this method, in order to separate the impurities, a part of the raw materials required for the production of copper carbonate or the like is consumed, so that it is economically inefficient. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a low-cost and simple method that does not consume alkali metal carbonate. A method for purifying an alkali metal carbonate of a calcium compound contained in an alkali metal carbonate, a refining device, and a metal carbonate solution purified by the method. The method for purifying an alkali metal carbonate solution of the present invention comprises: a preparation step of: preparing an alkali metal having a concentration of an alkali metal carbonate of 15% by weight or more for an alkali metal carbonate containing an impurity formed of a calcium compound; a carbonate solution; a precipitation step, in which the alkali metal carbonate solution is not precipitated, the alkali metal carbonate solution is maintained for a certain period of time, and the impurities dissolved in the alkali metal carbonate solution are precipitated; The liquid separation step is to separate the precipitated impurities from the alkali metal carbonate solution. In the refining method, it is preferred to include an alkali metal carbonate solution obtained by separating the precipitated impurities by diluting 1331985 with water to prepare a predetermined concentration of the alkali metal carbonate solution. Or in the precipitation step, diluting the metal citrate solution after the precipitation of the impurities (diluting step) with water, and then separating the precipitated impurities from the alkali metal carbonate solution by solid-liquid separation (solid separation step) can. The concentration of the alkali metal carbonate solution in the above-mentioned preparation step is preferably such that the concentration of the alkali metal carbonate which is saturated with respect to the alkali metal carbonate is 60% or more and the amount of the alkali metal carbonate is not reached. In the refining method, the aforementioned metal carbonate is preferably sodium carbonate or potassium carbonate. According to the method for producing an alkali metal carbonate solution according to the present invention, a calcium compound which is dissolved in an alkali metal carbonate solution is precipitated, and can be separated and removed. Therefore, the alkali metal carbonate in the aqueous solution is precipitated as a solid, and the conventional method of adsorbing impurities such as calcium ions on the precipitated solid is different, so that the alkali metal carbonate of the product is neither depleted, and The alkali metal carbonate solution is efficiently purified economically. Further, in the present purification method, since the temperature can be managed only for the alkali metal carbonate solution, and the impurities are precipitated after being held for a certain period of time, for example, it is necessary to carry out a special step such as the reaction of the aqueous solution with other substances. . Therefore, the apparatus configuration or other operations for carrying out the method can be simplified, and the alkali metal carbonate solution can be easily purified at low cost and at a low cost. 'Simple description of the figure / ris 1 Τ ^ Ί η mouth p 曰ττ / ν — Hawthorn λ. Τ> 、·Λ- ·1 Walking «φίΐ —X- *1. 乐丄固1乐s 兄口月峒Γ The trajectory of ττ, sorrow sucks S Sodium D gluten-like knives. Fig. 2 is a view showing a configuration of an example of a sodium carbonate aqueous solution refining device 7 1331985 according to an embodiment. Fig. 3 (a) and (b) are graphs showing the results of tests conducted to confirm the effects of the present invention. Fig. 4 is a graph showing the characteristics of the test results performed to confirm the effects of the present invention. [Embodiment] The best form of implementing the invention
作為本發明相關之鹼金屬碳酸鹽溶液之精製方法之實 施形態之一例’邊參照第1圖說明有關含有不純物的約之碳 酸納精製方法。第丨圖係有關碳酸鈉精製處理之流程圖。在 本實施之形態中，例如在工業用一般販售之碳酸鈉粉末(鹼 灰)作為原料’將其實施精製處理，例如就有關作為用以製 造銅鍍材料之碳酸銅的預定濃度碳酸鈉水溶液之精製情形 加以說明。工業用碳酸鈉粉末中，製造過程等之碳酸約等 不純物例如約含有數十〜1〇〇重量ppm。「精製」係指為要從 該等碳酸鈉去除不純物，獲得不含有不純物或不純物含量 少之高純度碳酸鈉所進行之處理。 首先，如第1圖所示，將不純物之鈣例如含有210重量 ppm之工業用碳酸鈉粉末，例如使之溶解於加溫至3〇ec水 20 中’例如將碳酸鈉濃度調製為30重量％之碳酸鈉水溶液【步 驟S1(調製步驟）】。此時，鈣濃度係依原料之碳酸鈉粉末， 及該水溶液濃度而決定，在本實施形態中為63重量ppm。通 常，用以製造碳酸銅之碳酸鈉水溶液，為欲在於碳酸銅生 成時之碳酸鈉與氯化銅等反應，穩定進行而獲得粒徑分布 8 均勻之板I銅起見，濃度例如約作成1G重量％之水溶液上 市。與其相對於本步料，為欲作成製品上市時之約3倍濃 度’而調衣為冋’農度之水溶液。$，相對於刚呂、贼之 水之飽和'谷解度’係由於碳酸鈉約為31.2重量％、鈣(例如 碳酸妈)約為0.7重量。/❶’故調製之碳酸銅水溶液中所含的任 何之物質，亦未達到飽和狀態。 其么’調製步驟所得之碳酸鈉水溶液，例如就與調製 時之同樣/皿度的加溫狀態，例如保持—天，則從該水溶液 析出躬化合物之固體【步驟S2(析出步驟）】。該步驟中，所 調製之奴酸鈉水麵巾之詞，即使未達龍和狀態仍可成 為固體使之析iB。其認域由於來自碳酸鈉之碳酸離子或 其他不純物之/辰度成為高濃度，故在於以碳酸約為主之齊 化合物之生成方向，形成水減可保持於平衡狀態所致。 與此相對，習知上雖將作為製品上市時之碳酸鈉水溶 液約調製為1〇重量％並將其保持後，由於使鈣化合物析出 之反應的反應速度遲緩，無法處理充分之量，故難適用於 工業的製程。對於此類問題經專研結果，發明人發現由於 使原料之石厌酸納粉末尚濃度溶解於水中，因而發現弼化合 物可在較短時間内析出。通常在溶液中所溶解之物質的反 應速度，會依反應物質之濃度比例而加速。因此，由於若 將碳酸納水溶液調製成高濃度，例如水溶液中所溶解之碳 酸離子或鈣濃度亦提咼，該結果認為使碳酸鈣等鈣化合物 析出之反應的反應速度可提高。 再者，碳酸鈉水溶液中所溶解之鈣可否析出之平衡問 題，認為係由於根據該水溶液中之碳酸離子或詞等之濃度 而決定，故該等之濃度愈高’則飼化合物析出之量可提高。 換言之，認為由於調製碳酸鈉水溶液之濃度愈高，愈多之 鈣作為鈣化合物析出，因此鈣被去除之比例提高。 在此，工業用碳酸鈉粉末所含之鈣量，由於會依其製 造廠或製造批號之不同而變化，故於精製碳酸鈉之各步驟 無法控制。因此’為要調製辦以南漢度存在之碳酸納水溶 液’須儘可能將多量之碳酸鈉粉末溶解於水中，亦必須將 同時被溶解之妈濃度調製為ifj》農度。但如同前述，由於相 對於30°c之水’碳酸鈉粉末之溶解度約為31.2重量％，故使 飽和溶解度以上之碳酸鈉粉末溶解時，製品之碳酸鈉與不 純物同時析出，因而關連到經濟上損失。 因此，本實施之形態中，係將碳酸鈉保持於不析出之 狀態，且若可將鈣濃度儘可能提高，而在於碳酸鈉的溶解 I未達到飽和溶解度之程度時，儘可能調製為高濃度之碳 酸鈉水溶液。由於諸如此類之理由，在調製步驟中，將碳 醆鈉水'谷液濃度調製成為例如30重量％，使碳酸鈉飽和溶 =之濃度少於約31.2重量％，且飽和溶解度成為6〇%以上之 令解度（約18.7重量％以上）。如此調製成之碳酸鈉水溶液保 j如天摘》農度可由數十重量ppm降低到約⑴重An example of the embodiment of the method for purifying the alkali metal carbonate solution according to the present invention will be described with reference to Fig. 1 for a method for purifying a sodium carbonate containing an impurity. The second chart is a flow chart for the sodium carbonate refining process. In the embodiment of the present invention, for example, sodium carbonate powder (alkali ash) which is generally sold in industry is used as a raw material, and it is subjected to a refining treatment, for example, a predetermined concentration of sodium carbonate aqueous solution as copper carbonate for producing a copper plating material. The refinement situation is explained. In the industrial sodium carbonate powder, an impurity such as carbonic acid in a production process or the like contains, for example, about several tens to about 10,000 ppm by weight. "Refining" means the treatment of removing impurities from such sodium carbonate to obtain high-purity sodium carbonate which does not contain impurities or impurities. First, as shown in Fig. 1, the calcium of the impurity contains, for example, 210 ppm by weight of industrial sodium carbonate powder, for example, dissolved in 3 〇 ec water 20, for example, the sodium carbonate concentration is adjusted to 30% by weight. Sodium carbonate aqueous solution [Step S1 (modulation step)]. At this time, the calcium concentration is determined by the sodium carbonate powder of the raw material and the concentration of the aqueous solution, and is 63 ppm by weight in the present embodiment. In general, the sodium carbonate aqueous solution for producing copper carbonate is stabilized by the reaction of sodium carbonate and copper chloride in the formation of copper carbonate, and the plate I having a uniform particle size distribution is obtained. The concentration is, for example, about 1 G. A weight percent aqueous solution is available. Instead of this step, it is an aqueous solution of about 3 times the concentration of the product to be made into a product. The saturation of the water relative to the water of the ruthenium and the thief is about 31.2% by weight of sodium carbonate and about 0.7% by weight of calcium (for example, carbonic acid mother). /❶' Therefore, any substance contained in the aqueous solution of copper carbonate prepared has not reached saturation. The aqueous solution of sodium carbonate obtained by the preparation step is, for example, the same as the heating state of the dish at the time of preparation, for example, a solid state of the ruthenium compound is precipitated from the aqueous solution [step S2 (precipitation step)]. In this step, the word "sodium sulphate" is prepared to form a solid even if it is not reached and the state is analyzed. Since the recognition range is such that the carbonic acid ions or other impurities from sodium carbonate have a high concentration, the formation of the water is reduced to a balanced state in the direction in which the carbonic acid is about the formation of the main compound. On the other hand, in the conventional case, since the sodium carbonate aqueous solution at the time of product introduction is prepared to about 1% by weight and is maintained, the reaction rate of the reaction for precipitating the calcium compound is delayed, and it is difficult to handle a sufficient amount, which is difficult. Suitable for industrial processes. As a result of special research on such problems, the inventors found that the ruthenium compound was precipitated in a relatively short period of time because the concentration of the analytic sodium powder of the raw material was dissolved in water. The rate of reaction of the substance normally dissolved in the solution is accelerated by the concentration ratio of the reactant. Therefore, when the aqueous sodium carbonate solution is prepared to a high concentration, for example, the concentration of the carbonic acid ion or calcium dissolved in the aqueous solution is also improved, and as a result, it is considered that the reaction rate of the reaction for precipitating the calcium compound such as calcium carbonate can be improved. Furthermore, the problem of the balance of the dissolution of calcium dissolved in the aqueous sodium carbonate solution is considered to be determined by the concentration of carbonate ions or words in the aqueous solution, so that the higher the concentration, the amount of the feed compound can be precipitated. improve. In other words, it is considered that the higher the concentration of the aqueous sodium carbonate solution is, the more calcium is precipitated as a calcium compound, so that the proportion of calcium removed is increased. Here, the amount of calcium contained in the industrial sodium carbonate powder varies depending on the manufacturer or the manufacturing lot number, so that the steps of purifying the sodium carbonate cannot be controlled. Therefore, in order to modulate the sodium carbonate solution present in the South Han Dynasty, it is necessary to dissolve a large amount of sodium carbonate powder in water as much as possible, and it is also necessary to adjust the concentration of the mother dissolved at the same time as ifj. However, as described above, since the solubility of the sodium carbonate powder with respect to 30 ° C is about 31.2% by weight, when the sodium carbonate powder having a saturated solubility or more is dissolved, the sodium carbonate of the product precipitates simultaneously with the impurities, thereby being related to the economy. loss. Therefore, in the embodiment of the present embodiment, sodium carbonate is maintained in a state where it is not precipitated, and if the calcium concentration can be increased as much as possible, and the dissolution I of sodium carbonate does not reach the saturation solubility, it is adjusted to a high concentration as much as possible. An aqueous solution of sodium carbonate. For the reasons of the above, in the preparation step, the carbon sodium sulphate water solution is adjusted to a concentration of, for example, 30% by weight, the sodium carbonate is dissolved at a concentration of less than about 31.2% by weight, and the saturated solubility is at least 6% by weight. The degree of solution (about 18.7% by weight or more). The sodium carbonate aqueous solution thus prepared can be reduced from tens of ppm to about (1).
Ppm。 、 析出步驟巾’使㈣成為g體析击後之碳酸釣水溶 液例如可由過遽器等去除辦化合物【步驟幻（固液分離步 帮）】。該固液分離步鄉中，在碳酸納水溶液中混雜之舞化 合物被分離。 析出之不純物被分離後之碳酸鈉水溶液’所使用之濃 度例如10重買％為止，以不含鈣元素之離子交換水等稀釋 【步驟S4(稀釋步驟)】。被稀釋之碳酸鈉水溶液巾的的濃度 約降低到2〜3重量ppm。 其次，被稀釋之碳酸鈉水溶液，導入於充填有離子交 換樹脂之吸附塔等與離子交換樹脂接觸，將析出步驟中未 析出而於水溶液中呈溶解狀態之約離子吸附去除【步驟 S5(吸附辣）】。吸时射所制之料交換则旨，例如， 如安白來交換樹脂【（Ambedite)，亦稱苯酚曱醛離子交換 樹脂（登錄商標）】IRC748等，以與鈉離子比較可選擇性地 吸附釣離子或鎭離子之型者為佳。由於接觸離子交換樹 脂’故溶解於碳酸鈉水溶液中之_子濃度例如可降低到 0.1重量ppm以下。 其次’根據前述流程圖說明有關精製碳酸納之精製袭 置。第2 _辭該精奴置之構成例。該裝置係由用以使 碳酸納粉末溶解於水’調製高濃度碳_水溶液之溶解槽 10 ;用以使碳錢水溶液中之触合物作成固體而析^ 滯留槽20;用以使析出之糾合物分離去除之過濾器3〇; 用以使触合物分雜之魏釣水雜稀釋之稀釋槽· 及用以使稀釋後之碳_水溶液中之如容解、吸附去除之 樹脂塔50等所構成。 詳而。之’ a解槽10係藉由原水供給闕U所介設之肩 水供給管，與未_之原水供給鋪接。原水供給仙 1331985 係用以達成使預定量之原料水連續地供給於溶解槽10之功 能。另，在溶解槽10之上方，設有儲藏碳酸鈉粉末之料斗9。 溶解槽10設有未圖示之計量器，作為一種供給方法以達成 使預定量之碳酸鈉粉末連續地、或間歇地供給於溶解槽10 5 之功能。 再者’溶解槽10中，設有用以攪拌溶解槽10内之碳酸 鈉水溶液之攪拌器12，及用以供給加溫之碳酸鈉水溶液蒸 氣之蒸氣供給管13a。另於溶解槽10之底部，安裝有底層配 管14a，構成可藉由底層泵14從溶解槽1〇抽取碳酸鈉水溶 10 液。在底層配管14a設有未圖示之溫度計，該溫度計連接於 溫度控制器15。溫度控制器15係具有因應貫流於底層配管 14a之碳酸鈉水溶液的溫度以開關蒸氣供給閥13，而藉由蒸 氣供給量之增減，以控制溶解槽10内之溶液維持於一定溫 度之功能。 15 底層配管14a係分支成回流配管16及抽取配管17，回流 配管16係用以達成貫流於底層配管14a之碳酸鈉水溶液的 一部分回流於溶解槽10之功能。另，抽取配管17係與滯留 槽20連接，將用以達成未回流於溶解槽10之碳酸鈉水溶液 抽取到滞留槽20之功能。 2〇 其次，就滯留槽20詳細說明。滯留槽20係從溶解槽10 接受之碳酸納水溶液之滯留時間’例如係具有可容納滯留6 小時容量之容器，周以作為析岀槽以達成使溶解於該溶液 中之碳酸鈉析出成為固體之功能。滯留槽20設有攪拌器21 及加熱器22，構成可將滯留槽20内之碳酸納水溶液保持於 12 1331985 均勾加溫。加熱器22介未圖示之溫度控制器，連接設置於 滞留槽20内未圖示之溫度計，由於調整加熱器^之輸出， 構成可將滞留槽20内之碳酸鈉水溶液之溫度保持於一定。 在滯留槽2G之底部，安裝有底層配管23a，構成可使躬 5化合物析出後之碳酸納水溶液，藉由底層粟23從滞留槽烈 ' 抽取底層栗23之排出侧之底層配管23a内，例如介設有收 納於過濾E等之過滤器3〇。過遽器3〇係用以達成從滯留槽 20抽取之碳酸鈉水溶液’使鈣化合物過濾後分離之固液分 ® 離方法之功能。固液分離方法如利用例示之過濾器30時不 10受限定；例如沈澱槽或液體旋風分離器等亦可利用。底層 配官23a於過濾器3〇之出口側，分支成回流配管24及抽取配 官25 ’回流配管24係用以達成使過濾器3〇過濾後之碳酸鈉 水溶液之一部分回流到滯留槽2〇之功能，而抽取配管25係 用以達成將殘餘之水溶液抽取到稀釋槽4〇之功能。 15 接著就稀釋槽40詳細說明。稀釋槽40係從滯留槽20接 支過;慮器30過渡妈化合物後之碳酸納水溶液’將其以水稀 • 釋成預定之濃度，例如係用以作為製品稀釋止上市時之濃 度的容器。稀釋槽40係藉由稀釋水供給闊41介設之稀釋水 供給管41a ’與未圖示之稀釋水供給桶連接。稀釋水供給閥 20 41，係用以達成使不含鈣元素等不純物之離子交換水等稀 釋水，連續供給於稀釋槽4〇之功能。稀釋水供給閥41係例 如藉介未圖示之流量控制器，與未圖示之線上(Online)分析 計連接’構成使被稀釋之碳酸鈉水溶液濃度，應線上控制 器測量之結果，可予以增減稀釋水之供給量β稀釋槽40内， 13 1331985 更S又有攪拌器42，用以達成使碳酸鈉水溶液與稀釋水攪拌 混合之功能。 在稀釋槽40之底部，安裝有底層崎―，構成將稀釋 成預定濃度之碳酸鈉水溶液，以底層泵43從稀釋槽4〇抽取 5之配置。底層配管43&係分支成回流配管44與抽取配管45 , - _流配管44係用以達成使被稀釋之碳酸納水溶液之一部 分回流於稀釋槽4〇之功能；抽取配管45係用以達成將殘餘 之水溶液抽取到樹脂塔5〇之功能。 樹脂塔50係作為吸附塔，具有使在於滯留槽2〇之未經 10分析而溶解於碳酸鈉水溶液中之約吸附去除之機能。樹脂 塔50係例如充填有球狀之離子交換樹脂之充填塔。樹脂塔 5〇具有之容量，可使溶解於碳酸鈉水溶液之㈣有充分的 _時間，以降低至製品規格之濃度。在樹脂塔50之底部 ι料有抽取配管5卜制以達精製之碳_水溶液抽 15取到未圖示之製品桶之功能。 % 其次，說明關於本實施形態之相關作用。由料斗9以預 疋之供給速度供給之碳賴粉末，與從原水供給管Ua供給 的預疋1之原水混合，在溶解槽1〇内以攪拌器 -2〇合’例如調製為製品之約3倍濃度(30重量％)之碳酸鈉水溶 ' 相當於第1圖之步驟叫。此時’碳酸鈉水溶液中溶解之 ，很度例如成為約數十重量ppm。另，碳義水溶液與從蒸 給官13a供給之蒸氣接觸，例如被加溫至3〇它。將調製 成之碳酸鈉水溶液輪送到滯留槽2〇。 輸送到♦留槽20之碳酸納水溶液，一邊受到搜拌器21 14 授拌與加熱器22之加溫，保持於平均滯留時間約6小時。 進行該保持之期間巾’從碳酸鈉水溶液析出不純物之辦 化合物’岭狀紐度降低至約1G重量ppm(第之步驟 52) 。鈣化合物析出之碳酸鈉水溶液，經過濾器3〇過濾，鈣 化合物被分離而輸送溶液到稀釋槽4〇(相當於第旧之步驟 53) 。 輸送到稀釋槽40之碳酸鈉水溶液，以攪拌器42邊攪拌 與從稀釋水供給管41a供給之稀釋水混合，將碳酸鈉水溶液 稀釋至作為製品上市之濃度(例如1〇重量％)為止(相當於第 1圖之步驟S4)。此時，水溶液中例如溶解有約2〜3重量卯m 之鈣，以該狀態輸送溶液至樹脂塔5〇。 輸送到樹脂塔50之碳酸鈉水溶液，在塔内與離子交換 樹脂接觸，選擇性地吸附去除溶解於水溶液中之鈣離子(相 當於第1圖之步驟S5)。經過以上之各種處理，碳酸鈉水溶 液，將溶解之鈣濃度例如精製到1重量ppm以下之狀態，將 水溶液輸送到製品桶。 根據以上所說明的本實施之形態，僅將碳酸鈉水溶液 調製成高濃度且予以保持’就可從該水溶液使鈣作成固體 析出。由於不需與其他物質等進行特別的反應操作，就可· 使不純物作成固體析出’故以簡單之裝置構成則可精製碳 酸鈉水溶液。該結果，碳酸鈉水溶液之精製裝置簡單化， 運轉操作之内容亦簡便，故設備成本或運轉成本可降低。 再者，由於將碳酸鈉水溶液之濃度提高到15重量％以 上，不純物之析出速度加快，而與水溶液之濃度低時比較， 在單位時間内可精製之碳酸鈉水溶液之處理量增加。另由 於將碳酸鈉水溶液之濃度作成高濃度，對於不純物去除之 比例亦可提高。此時，由於將碳軸水溶液之濃度，作成 相對於溶解有碳酸納之飽和溶解度為60%以上，且未達飽 5和冷解度之碳酸鈉量的濃度，不但使不純物析出之速度最 快，同時製品之碳酸鈉與不純物一起析出之固液分離步驟 中不被去除的最有效率之良好條件。 再者，析出之不純物被分離後，由於溶解於碳酸鈉水 /合液中之1¾，與離子交換樹脂接觸吸附去除，可使該水溶 液中之不純物展度更為降低。該結果，例如不純物之濃度 可精製成0.1重量卯心乂下的高純度之碳酸納水溶液。 根據本發明可精製之鹼金屬碳酸鹽，不受實施形態中 例不之碳酸鈉所限制。例如有關作為針鹽類等原料之碳酸 卸之精製，本發明亦可適用。另，原料之驗灰中亦含有由 15鎂所成之不純物時，經由接觸離子交換樹脂，可從碳酸納 水溶液去除該不純物。 再者，調製步驟中調製高濃度碳酸鈉水溶液之方法， 亦不受實施形態之例示者限制。例如採購含有不純物之低 浪度碳酸納水溶液，經由蒸發水分、濃縮水溶液以調製成 20高濃度亦可。 再者κ施形態中，將析出之鈣化合物分離後之碳酸 鈉水溶液，在稀釋步驟經稀釋後，雖於吸附步驟中使溶解 於該水溶液中之詞吸附去除，但對於稀釋步驟或吸附步驟 之有無’或該等步驟之順序，不受例示者所限制。例如， 16 1331985 析出之不純物於固液分離步驟中分離後，就以該碳酸納水 >谷液之原狀上市亦可；在稀釋步驟中僅經稀釋後上市亦 可另於固液分離步驟之後立即，於吸附步驟中使溶解之 不純物吸附去除，就以該碳酸鈉水溶液之原狀上市亦可； 5在吸附步驟之後，移行於稀釋步驟亦可。 此外，固液分離步驟與稀釋步驟之順序互換，將不純 物析出後之鹼金屬碳酸鹽溶液以水稀釋後，使析出之不純 物於固液分離步驟中分離之構成亦可，此後，更於吸附步 驟中使溶解之不純物吸附去除亦可。由於已知一旦析出之 10 不純物不會再度溶解。 (實施例） (實驗1) 有關石厌酸納水溶液之濃度對於約化合物析出反應之影 響進行評價。 15 (實施例1-1) 碳fee鈉粉末(工業用驗灰：转化合物含量為2職量即 溶解於離子交換水，濃度調製為3G重量％之碳酸納水溶 液。該等碳酸鈉水溶液邊授拌於室溫保持1小時，對於該全 量經吸引過渡所得母液中妈濃度進行測定。接著，將吸引 2〇過遽後之碳酸鈉水溶液，未作授拌而保持於室溫’共計經 則天後/再將全量吸引過渡所得母液中之妈濃度進行測 接$將及'^心濾後之碳酸鈉水溶液，未作攪拌而保 ； ^ °十’”二過4天後，再將全量吸引過濾所得母液中 之詞濃度進行測定。另於預定之適當時間，以目視觀察破 17 1331985 酸鈉水溶液之狀況。過濾時，以保持粒子徑0.5μιη之玻璃過 濾器過濾。實驗之結果顯示於第1表。另於第2表顯示，將 實驗結果所得之碳酸鈉水溶液，例如作為製品稀釋成上市 之10重量％水溶液時之鈣濃度的換算值。另於第1表、第2 5 表中，同時顯示實施例1-2〜1-3、比較例1-1之結果。 (第1表） 依碳酸鈉水溶液濃度之不同，鈣濃度（重量ppm)之經時變化 實施例 1-1 實施例 1-2 實施例 1-3 比較例 1-1 碳酸鈉濃度 30重量％ 20重量％ 15重量％ 10重量％ 初期》辰度 63 42 32 21 經過1小時後 27 24 20 14 經過1天後 8 12 12 12 經過4天後 9 13 14 13 (第2表） 10 顯示於第1表之結果，換算成10重量％之碳酸鈉水溶液之值 (約濃度：重量ppm) 實施例 1-1 實施例 1-2 實施例 1-3 比較例 1-1 碳酸鈉濃度 30重量％ 20重量％ 15重量％ 10重量％ 初期濃度 21 21 21 21 經過1小時後 9 12 13 14 經過1天後 3 6 8 12 經過4天後 3 6 9 13 18 1331985 (實施例1-2、1-3) 、15重量％之外， 將碳酸納水溶液之濃度分別作成2〇 與實施例卜1相同之條件進行試驗。 (比較例卜1) 量％之外，與實施例 將碳酸鈉水溶液之濃度作成1〇重 1-1相同之條件進行試驗。 (實驗1之考察) 根據實驗中之目視觀察的結果，調製碳酸納水溶液經 • 過1小時後’實施例w〜實施例卜3，比較例1-1之各個水溶 10液，發現有淡白色混濁。另，碳酸鈉水溶液之濃度俞古， 混濁程度愈大。在經過H、時之時間點，進行碳酸納^液 之吸引過濾時，獲得無混濁且清澄之水溶液。接著，在於 從保持開始經過1小時之時間點進行觀察，則於碳酸鈉水溶 液為15重量％(實施例1-3)、20重量％(實施例^2)、^重量％ 15 (實施例卜丨)之水溶液，發現淡白色混濁、白色沈澱物。另 一方面，10重量％(比較例1-1)之水溶液中，未曾發現類似 鲁 該等之混濁。對於該等之碳酸納水溶液再進行吸引過減， 獲得無混濁且清澄之水溶液。在於從保持開始經過4天之時 間點進行觀察，對於任何濃度之碳酸鈉水溶液，亦未發現 20 白色混濁或沈殿物。 - 將第1表、第2表所顯示之鈣濃度的經時的變化，標繪 之結果分別顯示於第3(a)圖、第3(b)圖。第3(a)圖、第3(b) 圖之橫軸係表示經過時間，縱軸係表示碳酸納水溶液中之 鈣濃度。碳酸鈉水溶液30重量％之結果以又形（X)標繪，其 19 趨勢線以實線表示。同樣的20重量％之結果以三角形（△) 標繪並以一點虛線表示趨勢線，而15重量％之結果以四角 形（_)標繪並以二點虛線表示趨勢線，另1〇重量％之結果以 菱形(◊)標繪並以虛線表示趨勢線。 根據第3(a)圖所顯示之實驗結果，對於實施例M〜實施 例M’比較例1-1之任—例，碳酸鈉水溶液中之鈣濃度皆平 穩地減少。鈣濃度之減少，認為係由於鈣化合物析出，碳 酸鈉水溶液中之鈣被消費的結果。另，關於任一之結果， 在於從保持開始經過時間1小時起至1天之期間中，鈣濃度 之減少速度亦快速，且隨著經過時間愈拉長則減少速度愈 遲緩；經過時間從1天到4天之期間中鈣濃度幾乎無變化。 關於這一點’認為係由於鈣化合物之析出，碳酸鈉水溶液 中之鈣濃度變為平衡狀態所致。 將碳酸鈉水溶液保持，從經過1小時後起至經過1天為 止’其水溶液内之鈣減少的速度，與實施例1-1〜實施例1-3， 比較例Μ之各實驗結果比較，則碳酸鈉水溶液之濃度愈 高，鈣之減少速度亦快速。關於這一點’認為係由於隨著 調製成高濃度之碳酸鈉水溶液，鈣或碳酸離子之濃度亦 兩’每化合物析出之速度加快，結果鈣之減少速度轉為快 速所致。 就顯示於第3(b)圖之圖表考察。第3〇?)圖係顯示各實施 例、比較例所得之實驗結果，稀釋成10重量％之碳醍鈞水 溶液時之鈣濃度(換算值”在10重量％濃度換算值中，各實 施例、比較例中之弼的初期濃度，雖於21重量ppm時一致， 差:著Γ持時間之經過’各個碳酸鈉水溶液之鈣濃度發生 、一 ρ在妷醆鈉水溶液作為30重量％(實施例M)時， 尺'合液保持1天’換算成10重量％後之鈣濃度減少到 重里ppm 4目對於初期濃度可去除約87%之舞。相對於此， 5隨著濃度為20重晉。/+ # 里里/〇之碳酸鈉水溶液時約71%(實施例 2)而15重5 %之水溶液時約57%(實施例1 -3)所調製之水 /合液之/辰度減低’鈣被去除之比例降低。因此，在1〇重量 /。之碳酸納水溶液巾，僅能去除43%之㈣（比較例M)。另， 以飼濃度作為重點’則在碳酸鈉濃度為3〇、2〇、15重量％(實 10 k例1_1〜實施例⑼時，相對於在於一天以内之保持時間， Τ使稀釋後之水溶液中之辦濃度成為1〇重量ppm以下’而在 水溶液之濃度為1〇重量％時，雖經過一天後仍無法使鈣濃 度成為10重量ppm以下。因此認為稀釋後之水溶液濃度，若 能於一天内可使成為10重量ppm以下，則本發明相關之精製 15方法可充分適用於工業的過程。 (實驗2) 關於在保持時間比較短促之時間帶，對碳酸鈉水溶液 中之轉濃度變化進行評價。 (實施例2-1) 20 調製與實施例Μ同樣條件之碳酸鈉水溶液(碳酸鈉濃 度30重量％)並保持，在經過1小時、2小時' 4小時、6小時 後’對於採取樣品之水溶液吸引過濾所得母液中之鈣濃度 進行測定。在本實施例中，為要更接近於第2圖所示的滯留 槽20内之狀態，將調製碳酸鈉水溶液之燒杯，安置於恆溫 21 1331985 槽内將水溶液加溫至30°C之點，與水溶液於保持期間中持 續以電磁片攪拌之點，與在室溫保持且僅於最初1小時進行 攪拌之實施例1-1的條件不同。另，對於燒杯内之碳酸鈉水 溶液之一部分，採取樣品吸引過濾後分析其結果之點，與 5 每於分析時將水溶液全量吸引過濾後分析之實施例1-1的 條件不同。換言之，由於在水溶液内所析出之辦化合物， 無法以過濾去除而蓄積之點，則與實施例1-1不同。關於該 等以外之實驗條件，由於與實施例1-1相同略去說明。實驗 結果顯示於第3表。另於第3表中，同時顯示比較例2-1之結 10 果及用以參考之實施例1-1之結果。 (第3表） 鈣濃度之變化 實施例 2-1 實施例 1-1 比較例 2-1 初期濃度 63 63 10 經過1小時後 29 27 5 經過2小時後 15 - 5 經過4小時後 8 - 5 經過6小時後 6 - 6 經過1天後 - 8 - 經過4天後 - 9 -Ppm. The precipitation step towel is used to remove (4) the carbonated water solution after the g-body is precipitated, for example, by removing the compound by a filter or the like [step magic (solid-liquid separation step)]. In the solid-liquid separation step, the mixed dance compound in the aqueous sodium carbonate solution was separated. The concentration of the sodium carbonate aqueous solution after the separation of the precipitated impurities is, for example, 10% by weight, and is diluted with ion-exchanged water containing no calcium element [Step S4 (dilution step)]. The concentration of the diluted sodium carbonate aqueous solution is reduced to about 2 to 3 ppm by weight. Next, the diluted sodium carbonate aqueous solution is introduced into an adsorption column packed with an ion exchange resin, and is contacted with an ion exchange resin, and is adsorbed and removed in the dissolution state without being precipitated in the precipitation step. [Step S5 (Adsorption Spicy )]. The exchange of materials by suction and injection is intended to, for example, be exchanged resin (Ambedite, also known as phenol furfural ion exchange resin (registered trademark)] IRC748, etc., to selectively adsorb with sodium ions. It is better to catch ions or cesium ions. The concentration of the sol that is dissolved in the aqueous sodium carbonate solution can be reduced to, for example, 0.1 ppm by weight or less due to contact with the ion exchange resin. Next, the refinement of refined sodium carbonate is described based on the above-described flowchart. The second _ resignation of the composition of the fine slave. The device is prepared by dissolving sodium carbonate powder in water to prepare a high-concentration carbon-water solution dissolution tank 10; for causing the contact compound in the carbon money aqueous solution to be solid and analyzing the retention tank 20; a filter for removing and removing the extracting compound 3; a dilution tank for diluting the mixed salt of the mixed salt, and a resin tower 50 for dissolving and adsorbing the diluted carbon-aqueous solution And so on. Detailed. The a tank 10 is provided by the shoulder water supply pipe provided by the raw water supply port U, and is supplied to the raw water supply. The raw water supply 1331985 is used to achieve the function of continuously supplying a predetermined amount of raw material water to the dissolution tank 10. Further, above the dissolution tank 10, a hopper 9 for storing sodium carbonate powder is provided. The dissolving tank 10 is provided with a meter (not shown), and as a supply method, a function of continuously or intermittently supplying a predetermined amount of sodium carbonate powder to the dissolving tank 10 5 is achieved. Further, the dissolution tank 10 is provided with a stirrer 12 for stirring the sodium carbonate aqueous solution in the dissolution tank 10, and a vapor supply pipe 13a for supplying the heated sodium carbonate aqueous solution vapor. Further, at the bottom of the dissolution tank 10, an underlayer pipe 14a is attached, and the bottom pump 14 is used to extract the sodium carbonate water-soluble solution from the dissolution tank 1 . A thermometer (not shown) is provided in the bottom pipe 14a, and the thermometer is connected to the temperature controller 15. The temperature controller 15 has a function of controlling the temperature of the solution in the dissolution tank 10 to be maintained at a constant temperature by switching the vapor supply valve 13 in response to the temperature of the sodium carbonate aqueous solution flowing through the bottom piping 14a. The bottom pipe 14a is branched into a return pipe 16 and an extraction pipe 17, and the return pipe 16 serves to recirculate a part of the sodium carbonate aqueous solution flowing through the bottom pipe 14a to the dissolution tank 10. Further, the extraction pipe 17 is connected to the retention tank 20, and functions to extract the sodium carbonate aqueous solution which is not returned to the dissolution tank 10 to the retention tank 20. 2〇 Next, the retention tank 20 will be described in detail. The retention time of the retention tank 20 in the sodium carbonate aqueous solution received from the dissolution tank 10 is, for example, a vessel capable of accommodating a capacity of 6 hours of residence, and is used as a precipitation tank to precipitate a sodium carbonate dissolved in the solution to be solid. Features. The retention tank 20 is provided with a stirrer 21 and a heater 22, and is configured to maintain the carbonic acid aqueous solution in the retention tank 20 at 12 133 1985. The heater 22 is connected to a thermometer (not shown) provided in the retention tank 20 via a temperature controller (not shown), and the temperature of the sodium carbonate aqueous solution in the retention tank 20 can be kept constant by adjusting the output of the heater. The bottom layer pipe 23a is attached to the bottom of the retention tank 2G, and an aqueous solution of the carbonic acid solution which can precipitate the cerium 5 compound is formed, and the bottom millet 23 is used to extract the bottom piping 23a of the bottom side of the bottom pump 23 from the stagnation tank, for example, A filter 3 收纳 housed in the filter E or the like is interposed. The filter 3 is used to achieve the function of the solid-liquid separation method for separating the calcium compound from the retention tank 20 to separate the calcium compound. The solid-liquid separation method is not limited as long as the filter 30 is exemplified; for example, a sedimentation tank or a liquid cyclone may be used. The bottom layer distribution member 23a is branched on the outlet side of the filter 3, and branches into a return pipe 24 and a discharge valve 25'. The return pipe 24 is used to achieve a partial return of the sodium carbonate aqueous solution filtered by the filter 3〇 to the retention tank 2〇. The function of the extraction pipe 25 is to achieve the function of extracting the residual aqueous solution into the dilution tank 4 . 15 Next, the dilution tank 40 will be described in detail. The dilution tank 40 is connected from the retention tank 20; the sodium carbonate aqueous solution after the transition of the mother compound is discharged into a predetermined concentration by water, for example, as a container for diluting the concentration at the time of market release. . The dilution tank 40 is connected to a dilution water supply tank (not shown) by a dilution water supply pipe 41a' interposed by the dilution water supply tank 41. The dilution water supply valve 20 41 is a function for continuously supplying the diluted water such as ion-exchanged water containing no impurities such as calcium to the dilution tank 4 . The dilution water supply valve 41 is connected to an on-line analyzer (not shown) by a flow controller (not shown), for example, and the concentration of the aqueous sodium carbonate solution to be diluted is measured by the on-line controller. The supply amount of the dilution water is increased or decreased in the dilution tank 40, and 13 1331985 further has a stirrer 42 for achieving the function of stirring and mixing the aqueous sodium carbonate solution and the dilution water. At the bottom of the dilution tank 40, a bottom layer is mounted, and an aqueous solution of sodium carbonate which is diluted to a predetermined concentration is formed, and the bottom pump 43 is taken out from the dilution tank 4〇. The bottom pipe 43& is branched into a return pipe 44 and an extraction pipe 45, and the -_flow pipe 44 is used to achieve a function of returning a portion of the diluted sodium carbonate aqueous solution to the dilution tank 4; the extraction pipe 45 is used to achieve The residual aqueous solution is extracted to the function of the resin column 5〇. The resin column 50 serves as an adsorption column and has a function of removing adsorption in the sodium carbonate aqueous solution in the retention tank 2 without being analyzed by the 10 analysis. The resin column 50 is, for example, a packed column filled with a spherical ion exchange resin. The resin column has a capacity to dissolve (4) of the aqueous sodium carbonate solution for a sufficient period of time to reduce the concentration to the product specification. At the bottom of the resin tower 50, there is a function of extracting a pipe 5 to obtain a refined product carbon-aqueous solution. % Next, the related effects of the present embodiment will be described. The carbon leaching powder supplied from the hopper 9 at the pre-twisting supply speed is mixed with the raw water of the pre-crush 1 supplied from the raw water supply pipe Ua, and is kneaded by the agitator-2 in the dissolving tank 1 ' to prepare, for example, a product. The 3 times concentration (30% by weight) of sodium carbonate water-soluble is equivalent to the step of Figure 1. At this time, it is dissolved in the sodium carbonate aqueous solution, and is, for example, about several tens of ppm by weight. Further, the aqueous carbon solution is brought into contact with the vapor supplied from the steaming member 13a, for example, heated to 3 Torr. The prepared sodium carbonate aqueous solution was sent to the retention tank 2〇. The aqueous solution of sodium carbonate which is transferred to the hopper 20 is heated by the stirrer 21 14 and heated by the heater 22, and maintained at an average residence time of about 6 hours. During the period in which the holding was carried out, the compound ridge of the precipitate from the aqueous sodium carbonate solution was reduced to about 1 G by weight (step 52). The sodium carbonate aqueous solution precipitated from the calcium compound is filtered through a filter 3, and the calcium compound is separated to transport the solution to the dilution tank 4 (equivalent to the first step 53). The sodium carbonate aqueous solution sent to the dilution tank 40 is mixed with the dilution water supplied from the dilution water supply pipe 41a while stirring by the agitator 42 to dilute the sodium carbonate aqueous solution to a concentration (for example, 1% by weight) which is listed as a product (equivalent to In step S4) of Fig. 1. At this time, for example, about 2 to 3 parts by weight of calcium is dissolved in the aqueous solution, and the solution is transferred to the resin column 5 in this state. The aqueous sodium carbonate solution sent to the resin column 50 is contacted with the ion exchange resin in the column to selectively adsorb and remove calcium ions dissolved in the aqueous solution (corresponding to step S5 in Fig. 1). After the above various treatments, the aqueous sodium carbonate solution is refined to a state of, for example, 1 ppm by weight or less, and the aqueous solution is transported to the product drum. According to the embodiment of the present embodiment described above, calcium can be solidified from the aqueous solution by preparing only a sodium carbonate aqueous solution at a high concentration and holding it. Since it is not necessary to carry out a special reaction operation with other substances or the like, the impurities can be precipitated as solids. Therefore, the sodium carbonate aqueous solution can be purified by a simple apparatus. As a result, the refining device for the sodium carbonate aqueous solution is simplified, and the contents of the operation operation are also simple, so that the equipment cost or the running cost can be reduced. Further, since the concentration of the aqueous sodium carbonate solution is increased to 15% by weight or more, the precipitation rate of the impurities is increased, and the amount of the sodium carbonate aqueous solution which can be purified per unit time is increased as compared with the case where the concentration of the aqueous solution is low. Further, since the concentration of the aqueous sodium carbonate solution is made high, the ratio of removal of impurities can be increased. At this time, since the concentration of the aqueous solution of the carbon axis is set to be higher than the concentration of sodium carbonate in which the saturated solubility of sodium carbonate is 60% or more, and the amount of sodium carbonate which is not saturated with 5 and the degree of cold solution is formed, not only the precipitation of impurities is fastest. At the same time, the most efficient and good condition for the solid-liquid separation step in which the sodium carbonate of the product is precipitated together with the impurities is not removed. Further, after the precipitated impurities are separated, they are dissolved in the sodium carbonate water/liquid mixture, and are adsorbed and removed by contact with the ion exchange resin, whereby the impurity spread in the aqueous solution can be further lowered. As a result, for example, the concentration of the impurities can be refined into a high-purity aqueous solution of sodium carbonate under a weight of 0.1 part by weight. The alkali metal carbonate which can be purified according to the present invention is not limited by the sodium carbonate which is not exemplified in the embodiment. For example, the present invention is also applicable to the purification of carbonic acid as a raw material such as a needle salt. Further, when the ash test of the raw material also contains an impurity formed of 15 mg, the impurity can be removed from the aqueous solution of sodium carbonate by contacting the ion exchange resin. Further, the method of preparing a high-concentration sodium carbonate aqueous solution in the preparation step is not limited by the examples of the embodiment. For example, a low-wavelength sodium carbonate aqueous solution containing impurities may be purchased, and a high concentration may be prepared by evaporating water and concentrating the aqueous solution. Further, in the κ application form, the sodium carbonate aqueous solution obtained by separating the precipitated calcium compound is diluted in the dilution step, and the word dissolved in the aqueous solution is adsorbed and removed in the adsorption step, but for the dilution step or the adsorption step The presence or absence of ' or the order of the steps is not limited by the instantiator. For example, after the separation of the impurities formed in 16 1331985 is separated in the solid-liquid separation step, it may be listed as the raw material of the sodium carbonate and the gluten solution; after dilution in the dilution step, it may be listed after dilution or after the solid-liquid separation step. Immediately, in the adsorption step, the dissolved impurities are adsorbed and removed, and the sodium carbonate aqueous solution may be listed as it is; 5 after the adsorption step, it may be transferred to the dilution step. Further, the order of the solid-liquid separation step and the dilution step are interchanged, and the alkali metal carbonate solution after the precipitation of the impurities is diluted with water, and the precipitated impurities are separated in the solid-liquid separation step, and thereafter, the adsorption step is further performed. The dissolved impurities may be adsorbed and removed. It is known that once the precipitated impurities are not dissolved again. (Example) (Experiment 1) The concentration of the aqueous solution of the anaerobic acid solution was evaluated for the influence of the precipitation reaction of the compound. 15 (Example 1-1) Carbon Fee sodium powder (industrial ash test: a sodium carbonate aqueous solution dissolved in ion-exchanged water at a concentration of 2 parts by weight, and adjusted to a concentration of 3 g% by weight. The mixture was kept at room temperature for 1 hour, and the concentration of the mother liquid in the mother liquor obtained by the total amount of the suction was measured. Then, the aqueous sodium carbonate solution after the adsorption of 2 〇 was sucked and kept at room temperature without being mixed. After / after the full amount of the mother's concentration in the transitional mother liquor is measured and measured, and the sodium carbonate aqueous solution after the filtration of the heart will be protected without stirring; ^ ° ten '" after two days, the full amount will be attracted The concentration of the word in the mother liquor obtained by filtration was measured, and the condition of the sodium sulphate solution of 17 133 1985 was visually observed at the appropriate time. When filtering, the glass filter was kept at a particle diameter of 0.5 μm. The results of the experiment are shown in Table 1. Further, in Table 2, the sodium carbonate aqueous solution obtained by the experiment, for example, is converted into a converted value of the calcium concentration of the product into a 10% by weight aqueous solution of the market. In Tables 1 and 5, The results of Examples 1-2 to 1-3 and Comparative Example 1-1 are shown. (Table 1) Change in time of calcium concentration (ppm by weight) depending on the concentration of aqueous sodium carbonate solution Example 1-1 Example 1-2 Example 1-3 Comparative Example 1-1 Sodium carbonate concentration 30% by weight 20% by weight 15% by weight 10% by weight Initial "Changing degree 63 42 32 21 After 1 hour 27 24 20 14 After 1 day 8 12 12 12 After 4 days, 9 13 14 13 (Table 2) 10 The value shown in Table 1 is converted into a 10% by weight aqueous sodium carbonate solution (approximate concentration: ppm by weight). Example 1-1 Example 1 -2 Example 1-3 Comparative Example 1-1 Sodium carbonate concentration 30% by weight 20% by weight 15% by weight 10% by weight Initial concentration 21 21 21 21 After 1 hour 9 12 13 14 After 1 day 3 6 8 12 After 4 days, 3 6 9 13 18 1331985 (Examples 1-2, 1-3) and 15% by weight, the concentrations of the aqueous sodium carbonate solution were respectively determined to be 2 〇 and tested under the same conditions as in Example 1. In the example, 1) the amount of % was measured in the same manner as in the example, the concentration of the aqueous sodium carbonate solution was set to 1 〇 1-1. Examination) According to the results of visual observation in the experiment, the aqueous solution of sodium carbonate was prepared for 1 hour, and then each of the water-soluble liquids of Example 1-1 was found to have a pale white turbidity. The concentration of the aqueous solution of sodium carbonate is Yugu, and the degree of turbidity is greater. When the H, liquid adsorption and filtration are carried out at the time point of H, a turbid and clear aqueous solution is obtained. Next, in the observation of the time from the start of the holding for 1 hour, the sodium carbonate aqueous solution was 15% by weight (Example 1-3), 20% by weight (Example 2), and % by weight 15 (Example Bu An aqueous solution of 丨) was found to be pale white turbid and white precipitate. On the other hand, in the aqueous solution of 10% by weight (Comparative Example 1-1), turbidity similar to that of Lu was not found. The aqueous sodium carbonate solution was further subjected to suction reduction to obtain a turbid and clear aqueous solution. It was observed from the time point of 4 days from the start of the holding, and no white turbidity or sediment was observed for any concentration of sodium carbonate aqueous solution. - The temporal changes in the calcium concentration shown in the first table and the second table are plotted in the third (a) and third (b) views. In the third (a) and third (b) graphs, the horizontal axis indicates the elapsed time, and the vertical axis indicates the calcium concentration in the aqueous sodium carbonate solution. The result of 30% by weight of the aqueous sodium carbonate solution is plotted in the shape of (X), and the trend line of 19 is indicated by a solid line. The same result of 20% by weight is plotted as a triangle (△) and the trend line is indicated by a dotted line, while the result of 15% by weight is plotted in a square (_) and the trend line is indicated by a two-dotted line, and the other is 1% by weight. The results are plotted in diamonds (◊) and the trend lines are indicated by dashed lines. According to the results of the experiment shown in Fig. 3(a), the calcium concentrations in the aqueous sodium carbonate solution were all reduced steadily in the examples of Examples M to M' of Comparative Example 1-1. The decrease in the calcium concentration is thought to be the result of the consumption of calcium in the sodium carbonate aqueous solution due to the precipitation of the calcium compound. In addition, as a result of either, the rate of decrease in the concentration of calcium is also rapid during the period from one hour to one day from the start of the holding, and the rate of decrease is slower as the elapsed time is longer; the elapsed time is from 1 There was almost no change in calcium concentration during the day to 4 days. In this regard, it is considered that the calcium concentration in the aqueous sodium carbonate solution is balanced due to the precipitation of the calcium compound. The sodium carbonate aqueous solution was maintained, and the rate of calcium reduction in the aqueous solution was changed from 1 hour after the lapse of one hour to the results of the respective experiments of Examples 1-1 to 1-3 and Comparative Example. The higher the concentration of the aqueous sodium carbonate solution, the faster the rate of calcium reduction. In this regard, it is considered that since the concentration of calcium or carbonate ions is increased as the concentration of calcium or carbonate ions is increased with the preparation of a high concentration aqueous solution of sodium carbonate, the rate of decrease in calcium is rapidly changed. The chart shown in Figure 3(b) is examined. Fig. 3 shows the results of the experiments obtained in the respective examples and comparative examples, and the calcium concentration (converted value) in the case of diluting into a 10% by weight aqueous solution of carbon ruthenium in the concentration conversion value of 10% by weight, each example, The initial concentration of ruthenium in the comparative example was consistent at 21 ppm by weight, and the difference was that the calcium concentration of each of the sodium carbonate aqueous solutions occurred during the holding time, and one ρ was 30% by weight in the aqueous solution of sodium hydride (Example M). In the case of the ruler's liquid retention for 1 day, the calcium concentration after conversion to 10% by weight is reduced to the weight of the ppm. The target can remove about 87% of the dance for the initial concentration. In contrast, 5 is increased with a concentration of 20. /+ # about 71% of the aqueous sodium carbonate solution of Lili/〇 (Example 2) and about 57% of the aqueous solution of 15% by weight of 5% (Example 1-3) 'The proportion of calcium removed is reduced. Therefore, only 4% of the sodium carbonate aqueous solution can be removed (IV) (Comparative Example M). In addition, the concentration of sodium carbonate is 3 〇, 2〇, 15% by weight (real 10k case 1_1~ embodiment (9), relative to the retention time within one day, Τ When the concentration of the aqueous solution is 1% by weight or less in the diluted aqueous solution, and the concentration of the aqueous solution is 1% by weight, the calcium concentration cannot be made 10 ppm by weight or less after one day. Therefore, the concentration of the aqueous solution after dilution is considered to be If it can be 10 ppm by weight or less in one day, the method of refining 15 according to the present invention can be sufficiently applied to an industrial process. (Experiment 2) Regarding the time zone in which the holding time is relatively short, the rotation in the sodium carbonate aqueous solution The concentration change was evaluated. (Example 2-1) 20 An aqueous sodium carbonate solution (sodium carbonate concentration: 30% by weight) was prepared and maintained under the same conditions as in Example ', after 1 hour, 2 hours '4 hours, 6 hours'. The calcium concentration in the mother liquor obtained by suction filtration of the aqueous solution of the sample is measured. In the present embodiment, in order to be closer to the state in the retention tank 20 shown in Fig. 2, a beaker for modulating the aqueous sodium carbonate solution is placed in the beaker. Constant temperature 21 1331985 The temperature of the aqueous solution was raised to 30 ° C in the tank, and the aqueous solution was kept at the point of stirring with the electromagnetic sheet during the holding period, and kept at room temperature and only at the initial 1 The conditions of Example 1-1 were different when stirring. In addition, for one part of the sodium carbonate aqueous solution in the beaker, the sample was suction-filtered and analyzed, and the result was analyzed, and 5 was analyzed by suction after filtration. The conditions of Example 1-1 are different. In other words, the compound which is precipitated in the aqueous solution cannot be removed by filtration and is different from Example 1-1. The experimental conditions other than these are implemented. The same is omitted in Example 1-1. The experimental results are shown in Table 3. In Table 3, the results of Comparative Example 2-1 and the results of Example 1-1 for reference are also shown. 3 Table) Variation of calcium concentration Example 2-1 Example 1-1 Comparative Example 2-1 Initial concentration 63 63 10 After 1 hour, 29 27 5 After 2 hours, 15 - 5 After 4 hours, 8 - 5 After 6 After 6 - 6 after 1 day - 8 - after 4 days - 9 -
(比較例2-1) 15 使用粉末中之鈣化合物含量少之碳酸鉀（鈣化合物含 量為33重量ppm)外，與實施例2-1同樣條件下進行實驗。 22 1331985 (實驗2之考察） 顯示於第3表之鈣濃度之經時變化，標繪於圖中之結果 顯示於第4表。橫軸係表示經過時間，縱軸係表示碳酸鈉水 溶液中之角濃度。實施例2-!之結果以四角形（□)標繪，比 - 5較例2_1之結果以三角形(▲)標繪。另作為參考顯示之實施 例M之結果以又形⑻標繪。另，實線係表示各個漢度變化 之趨勢線。 根據第4圖之圖表，實施例2·卜比較例2_丨之任一情形 φ 中，亦由於碳酸鈉水溶液保持，水溶液中鈣濃度顯示平穩 10地減少。另，發現鈣之減少速度的變化，在保持時間之短 促領域時變為快速，隨著保持時間之拉長而減少速度變為 遲緩，顯示了與實驗1相同之傾向。另比較實驗例2_i與比 較例2-1，則可了解碳酸鈉水溶液之濃度雖相同，但於水溶 液之調製時間點，鈣的初期濃度不同之情形時，初期濃度 15愈尚，鈣之減少速度及其去除比例愈高。另於實施例2-1與 實施例1-1，在碳酸鈉水溶液中之鈣濃度的變化，未發現有 • 顯著的差異。 (實驗3) 使碳酸鈉水溶液與離子交換樹脂接觸，實施該水溶液 • 20 中含有之鈣或鎂吸附去除實驗。 ' (實驗方法） 官柱中填充離子交換樹脂【安白來交換樹脂「登錄商 標」IRC748】 50mL，在該管柱通過濃度1〇重量％之碳酸鈉 水溶液(鈣含量1.3重量Ppm，鎂含量〇 5重量ppm)。總共通過 23 1331985 液量(相當於樹脂量之騰之量）之碳酸納水溶液對 於每通過液量150mL(相當於樹脂量之3倍之量）通過管柱之 水溶液，採取樣品、測定約濃度及鎮滚度。以流動之方向 為下降流’空間速度為n。另，管柱備有管套，在該管 5套以60°c之溫水循環。實驗結果顯示於第4表。 _ (第4表） 與離子交換觸之賴^巾之*純物的濃度 處理倍量 — 鈣濃度(重量IJpm) 鎂濃度(重量ppm) 原液 1.3 0.5 0〜3 0.1以下 0.1以下 3〜6 0.1以下 0.1以下 6^9 0.1以下 0.1以下 9〜12 0.1以下 0.1以下 12〜15 ^ 0.1以下 0.1以下 15〜18 0.1以下 0.1以下 (實驗3之考察） 1〇 滅第1表顯示之結果，有_及敎任-種，在於相 田於樹月曰量之18倍量之碳酸鈉水溶液的溶液通過期間中， 心疋將I等不純物之濃度減低到0· 1重量ppm。根據該結 果，可了解如要將碳酸納水溶液保持，使析出之不純物分 離所得之水溶液更為精製時，藉使之與離子交換樹脂接 15觸’獲得4乎不含不純物且高純度之水溶液。 【圖式簡I説明】 第1圖係說明有關實施形態之碳酸鈉水溶液精製方法 24 1331985 之流程圖。 第2圖係顯示有關實施形態之碳酸鈉水溶液精製裝置 之一例之構成圖。 第3(a)、（b)圖係顯示用以確認本發明之效果，所進行 之試驗結果之特性圖。 第4圖係顯示用以確認本發明之效果，所進行之試驗結 果之特性圖。 【主要元件符號說明】(Comparative Example 2-1) The experiment was carried out under the same conditions as in Example 2-1 except that potassium carbonate having a small calcium compound content in the powder (the content of the calcium compound was 33 ppm by weight) was used. 22 1331985 (Experiment of Experiment 2) The change in calcium concentration shown in Table 3, the results plotted on the graph are shown in Table 4. The horizontal axis represents the elapsed time, and the vertical axis represents the angular concentration in the sodium carbonate aqueous solution. The result of Example 2 -! is plotted in a square (□), and the result of Example 2_1 is plotted as a triangle (▲) than -5. The results of Example M, which is also shown as a reference, are plotted in the shape of (8). In addition, the solid line indicates the trend line of each Han degree change. According to the graph of Fig. 4, in any of the cases of Example 2, Comparative Example 2_丨, φ, the calcium concentration in the aqueous solution showed a steady decrease as the sodium carbonate aqueous solution was maintained. Further, it was found that the change in the rate of decrease in calcium became rapid in the case where the holding time was short, and the speed was slowed as the holding time was elongated, showing the same tendency as in Experiment 1. Comparing Experimental Example 2_i with Comparative Example 2-1, it can be understood that the concentration of the aqueous sodium carbonate solution is the same, but when the initial concentration of calcium is different at the time of preparation of the aqueous solution, the initial concentration 15 is more, and the rate of calcium reduction is the same. The higher the ratio and its removal rate. Further, in Example 2-1 and Example 1-1, no significant difference was observed in the change in the calcium concentration in the aqueous sodium carbonate solution. (Experiment 3) An aqueous solution of sodium carbonate was brought into contact with an ion exchange resin to carry out an adsorption removal test of calcium or magnesium contained in the aqueous solution. ' (Experimental method) Filling the ion exchange resin in the official column [Anbai to exchange resin "registered trademark" IRC748] 50mL, in the column through a concentration of 1% by weight of sodium carbonate aqueous solution (calcium content 1.3 weight Ppm, magnesium content 〇 5 ppm by weight). A total of 23 1331985 liquid amount (corresponding to the amount of resin) of sodium carbonate aqueous solution for each passing liquid amount of 150mL (corresponding to 3 times the amount of resin) through the column of the aqueous solution, taking samples, measuring the concentration and Town rolling. The flow direction is the downward flow, and the space velocity is n. In addition, the pipe string is provided with a pipe sleeve, and 5 sets of the pipe are circulated with warm water of 60 ° C. The experimental results are shown in Table 4. _ (4th table) Concentration of pure substance concentration with ion exchange touch-sensitive towel - Calcium concentration (weight IJpm) Magnesium concentration (ppm by weight) Stock solution 1.3 0.5 0~3 0.1 or less 0.1 or less 3 to 6 0.1 The following 0.1 or less 6^9 0.1 or less 0.1 or less 9 to 12 0.1 or less 0.1 or less 12 to 15 ^ 0.1 or less 0.1 or less 15 to 18 0.1 or less 0.1 or less (experiment 3) 1 annihilation The result shown in the first table, there is _ In the solution passage period of the sodium carbonate aqueous solution of 18 times the amount of the amount of the amount of the sodium sulphate in the phase of the sapling, the concentration of the impurity such as I is reduced to 0.1 ppm by weight. According to the results, it is understood that if the aqueous solution of sodium carbonate is to be maintained, and the aqueous solution obtained by separating the precipitated impurities is more refined, it is obtained by a 15 touch with the ion exchange resin to obtain an aqueous solution containing no impurities and high purity. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing a method for purifying a sodium carbonate aqueous solution according to an embodiment of the invention. Fig. 2 is a view showing a configuration of an example of a sodium carbonate aqueous solution refining device according to an embodiment. Fig. 3 (a) and (b) are graphs showing the results of tests conducted to confirm the effects of the present invention. Fig. 4 is a graph showing the characteristics of the test results performed to confirm the effects of the present invention. [Main component symbol description]
9...料斗 23...底層粟 10...溶解槽 23a...底層配管 11...原水供給閥 24..·回流配管 11a...原水供給管 25...抽取配管 12...攪拌器 30…過遽器 13…蒸氣供給閥 40...稀釋槽 13a...蒸氣供給管 41...稀釋水供給閥 14...底層泵 41a...稀釋水供給管 14a...底層配管 42...攪拌器 15...溫度控制器 43...底層泵 16...回流配管 43a...底層配管 17...抽取配管 44...回流配管 20...滯留槽 45...抽取配管 2]…攪拌器 50...樹脂槽 22...加熱器 51...抽取配管 259...hopper 23...bottom millet 10...dissolution tank 23a...bottom pipe 11...raw water supply valve 24...reflow pipe 11a...raw water supply pipe 25...extraction pipe 12 ...agitator 30...passer 13...vapor supply valve 40...dilution tank 13a...vapor supply pipe 41...dilution water supply valve 14...bottom pump 41a...diluted water supply pipe 14a...bottom pipe 42...agitator 15...temperature controller 43...bottom pump 16...return pipe 43a...bottom pipe 17...exhaust pipe 44...return pipe 20 ...retention tank 45...extraction pipe 2]...agitator 50...resin tank 22...heater 51...extraction pipe 25