200946903 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種硫離子含量檢測方法，詳言之，係關 於一種煉焦廢水硫化物含量之線上檢測方法。 【先前技術】 煉焦廢水係來自於800°C之煉焦爐，該煉焦廢水包括多種複 雜成分，包括銨離子、氰離子、硫氰離子、氯離子、微量鐵 離子及極性芳香族化合物。其中，以硫化物為對象進行分 析，其他雜質成分之含量遠大於硫化物之含量。因大量雜質 之存在，習知之檢測方法皆會受到干擾，而無法直接進行線 上檢測。 習知之硫化物檢測方法包括銀電極之硝酸銀電位滴定法、 銀電極之硫酸銅電位滴定法、具硫化銀塗層（Coating-Ag2S)Ag 電極之電位滴定法、離子選擇電極（Ion Selective Electrode)法 及甲烯藍比色法。其中，因煉焦廢水之其他雜質成分（干擾物 質）之含量遠大於硫化物之含量，其會造成銀電極電位滴定法 受到干擾，使得檢測結果嚴重失真。另外，煉焦廢水之鐵離 子則會干擾離子選擇電極法之檢測，導致檢測結果產生偏 差。 如上所述，對於銀電極而言，會因受到其他雜質成分之干 擾，而無法找到終點電位；離子選擇電極法及甲烯藍比色法 則由於分析數值非常不穩定，檢測結果容易產生較大之偏 差。 因此，有必要提供一創新且富有進步性之煉焦廢水硫化物 123107.doc 200946903 含量之線上檢測方法，以解決上述問題。 【發明内容】 本發明之目的在於提供一種煉焦廢水硫化物含量之線上檢 測方法，該檢測方法包括：（a)提供一樣本煉焦廢水；（b)計算 該樣本煉焦廢水之一干擾性硫化物含量及一實際硫化物含 量；（c)根據該干擾性硫化物含量及該實際硫化物含量計算一 比例常數；（d)提供一線上分析裝置，該線上分析裝置具有一 _ 鉑電極，且通入一待測煉焦廢水至該線上分析裝置中，該待 測煉焦廢水具有待測硫化物，該待測硫化物具有一當量值； 及（e)進行一第一滴定步驟，加入一第一滴定溶液至該線上分 析裝置内之該待測煉焦廢水中，部分該第一滴定溶液與該待 測硫化物反應，以還原形成硫；⑴進行一第二滴定步驟，以 一第二滴定溶液與與未反應之部分該第一滴定溶液反應，並 利用該鉑電極量測一滴定終點電位；及（g)根據所加入之該第 一滴定溶液及該第二滴定溶液之體積及濃度、該當量值及該 φ 比例常數，以該線上分析裝置計算得出該待測硫化物之含 量。 本發明之煉焦廢水硫化物含量之線上檢測方法，係以該鉑 電極作為滴定電極，其不易受到煉焦廢水之其他雜質成分之 干擾，且該鉑電極可量測至極低之終點電位，故可準確地檢 測出煉焦廢水中硫化物之含量。並且，本發明之煉焦廢水硫 化物含量之線上檢測方法，可直接於線上檢測煉焦廢水中硫 化物之含量，故檢測方法簡單且快速。 【實施方式】 123107.doc 200946903 圖1顯示本發明煉焦廢水硫化物含量之線上檢測方法之流程 圖。參考步驟S11，首先提供一樣本煉焦廢水。參考步驟 S12，計算該樣本煉焦廢水之一干擾性硫化物含量及一實際硫 化物含量。參考步驟S13，根據該干擾性硫化物含量及該實際 硫化物含量計算一比例常數。在本實施例中，該比例常數係 為該實際硫化物含量及該干擾性硫化物含量之比值。較佳 地，該比例常數係為0.01至0.5之間。 ' 在本實施例中，其係以鉑電極電位滴定法進行初步之硫化 物含量檢測，以獲得該樣本煉焦廢水之該干擾性硫化物含 量。 在本實施例中，該實際硫化物含量之計算包括以下步驟。 首先，加入一參考醋酸鋅（Zn(CH3COO)2)溶液於該樣本煉焦廢 水中，以反應生成硫化鋅（ZnS)，其化學反應式如下：200946903 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a method for detecting a sulfur ion content, and more particularly to an on-line detection method for a sulfide content of a coking wastewater. [Prior Art] The coking wastewater is derived from a coke oven at 800 ° C. The coking wastewater includes various complex components including ammonium ions, cyanide ions, thiocyanate ions, chloride ions, trace iron ions, and polar aromatic compounds. Among them, the sulfide is used for analysis, and the content of other impurity components is much larger than the content of the sulfide. Due to the presence of a large amount of impurities, conventional detection methods are subject to interference, and it is not possible to directly perform on-line detection. The known sulfide detection methods include silver titanate potentiometric titration of silver electrode, copper titanate potentiometric titration of silver electrode, potentiometric titration method of coating with silver sulfide coating (Coating-Ag2S), and ion selective electrode (Ion Selective Electrode) method. And the methene blue colorimetric method. Among them, the content of other impurity components (interfering substances) of the coking wastewater is much larger than the content of the sulfide, which causes the silver electrode potentiometric titration to be disturbed, and the detection result is seriously distorted. In addition, the iron ions of the coking wastewater interfere with the detection of the ion selective electrode method, resulting in a deviation of the detection results. As described above, for the silver electrode, the end point potential cannot be found due to interference with other impurity components; the ion selective electrode method and the methine blue colorimetric method are very unstable due to the analysis value, and the detection result is likely to be large. deviation. Therefore, it is necessary to provide an innovative and progressive method for the determination of the content of sulfide wastewater in the coking wastewater 123107.doc 200946903 to solve the above problems. SUMMARY OF THE INVENTION An object of the present invention is to provide an on-line detection method for sulfide content of coking wastewater, which comprises: (a) providing the same coke wastewater; (b) calculating one of the sample coking wastewaters And an actual sulfide content; (c) calculating a proportionality constant based on the interfering sulfide content and the actual sulfide content; (d) providing an on-line analysis device having a platinum electrode and accessing a coking waste water to be tested in the online analysis device, the coking waste water to be tested has a sulfide to be tested, the sulfide to be tested has an equivalent value; and (e) performing a first titration step, adding a first titration The solution is sent to the coking waste water to be tested in the analysis device, and part of the first titration solution reacts with the sulfide to be tested to reduce sulfur to form sulfur; (1) performing a second titration step, and a second titration solution and The unreacted portion of the first titration solution is reacted, and the platinum electrode is used to measure a titration end point potential; and (g) according to the first titration solution added and the first Volume and concentration of titration solution, should the magnitude and φ proportional constant, means to calculate the line analysis results of the sulphide content of the test. The on-line detection method for the sulfide content of the coking wastewater of the present invention uses the platinum electrode as a titration electrode, which is not easily interfered by other impurity components of the coking wastewater, and the platinum electrode can be measured to a very low end potential, so that it can be accurately The content of sulfide in the coking wastewater was detected. Further, the on-line detection method of the sulfur content of the coking wastewater of the present invention can directly detect the content of sulfide in the coking wastewater on the line, so the detection method is simple and rapid. [Embodiment] 123107.doc 200946903 Fig. 1 is a flow chart showing an on-line detection method for the sulfide content of the coking wastewater of the present invention. Referring to step S11, the same coke wastewater is first provided. Referring to step S12, one of the sample coking wastewater is calculated as an interfering sulfide content and an actual sulfide content. Referring to step S13, a proportionality constant is calculated based on the interfering sulfide content and the actual sulfide content. In this embodiment, the proportionality constant is the ratio of the actual sulfide content to the interfering sulfide content. Preferably, the proportionality constant is between 0.01 and 0.5. In the present embodiment, the preliminary sulfide content was measured by a platinum electrode potentiometric titration to obtain the interfering sulfide content of the sample coke wastewater. In the present embodiment, the calculation of the actual sulfide content includes the following steps. First, a reference zinc acetate (Zn(CH3COO)2) solution is added to the sample coke waste water to react to form zinc sulfide (ZnS), and the chemical reaction formula is as follows:
H2S+Zn(CH3COO)2—ZnS i +2CH3COOH 接著，過濾該硫化鋅。接著，以稀鹽酸溶解還原該硫化鋅 Φ 為硫化氫（H2S)及氯化鋅（ZnCl2)溶液，其化學反應式如下：H2S + Zn(CH3COO)2 - ZnS i + 2CH3COOH Next, the zinc sulfide is filtered. Next, the zinc sulfide Φ is dissolved in dilute hydrochloric acid to form a solution of hydrogen sulfide (H2S) and zinc chloride (ZnCl2), and the chemical reaction formula is as follows:
ZnS+2HCl^ H2S+ZnCl2 接著，進行一第一參考滴定步驟，加入碘（12)溶液至該硫化 氫及氯化鋅溶液中，部分碘與該硫化氳反應生成碘化氫（HI)及 硫（S)，其化學反應式如下：ZnS+2HCl^H2S+ZnCl2 Next, a first reference titration step is carried out, an iodine (12) solution is added to the hydrogen sulfide and zinc chloride solution, and a part of iodine reacts with the cesium sulfide to form hydrogen iodide (HI) and sulfur. (S), its chemical reaction formula is as follows:
H2S+I2->2HI+S 接著，進行一第二參考滴定步驟，加入硫代硫酸鈉溶液至 該碘溶液、該硫化氫及氣化鋅溶液之混合溶液中，使硫代硫 酸鈉與未反應之部分碘反應生成碘化鈉（Nal)及硫酸鈉 123107.doc 200946903 (Na2S406)，並且，以一參考鉑電極量測一參考滴定終點電 位，並終止該第二參考滴定步驟，其化學反應式如下： 2Na2S2〇3+l2-> 2NaI+ Na2S4〇6 最後，根據所加入之該碘溶液及該硫代硫酸鈉溶液之體積 及濃度、該硫化氫之當量值，計算得出該樣本煉焦廢水之該 實際硫化物之含量。其中，該第二參考滴定終點電位係為300 至500毫伏特（mV)。 ' 在本實施例中，該樣本煉焦廢水之該實際硫化物含量係以 下方程式（1)計算而得： ^ A (msA (Λ^χΑΓ2Κ2)χΜχ1000 實際硫化物含量I ^- -------(1) 其中，川為碘溶液之當量濃度；乂1為碘溶液加入量（mL) ; N2 為Na2S203溶液之當量濃度；V2為溶液之終點消耗量（mL) ; Μ 為硫化氳之當量值17 ; W為該樣本煉焦廢水之體積（mL)。 參考步驟S14，提供一線上分析裝置，該線上分析裝置具有 一鉑電極，且通入一待測煉焦廢水至該線上分析裝置中，該 〇 待測煉焦廢水具有待測硫化物，該待測硫化物具有一當量值 (在本實施例中為硫化氫之當量值17)。根據不同之應用，該鉑 , 電極可選擇性地為雙鉑電極。在本實施例中，本發明預先設 定一滴定終點電位設定值至該分析裝置，其中，該滴定終點 電位設定值係介於200至600毫伏特（mV)之間，較佳地，該滴 定終點電位設定值係介於300至500毫伏特之間。 參考步驟S15，進行一第一滴定步驟，加入一第一滴定溶液 至該線上分析裝置内之該待測煉焦廢水中，部分該第一滴定 溶液與該待測硫化物反應，以還原形成硫。在本實施例中， 123107.doc -9- 200946903 所加入之該第一滴定溶液係為埃溶液。 參考步驟S16,進行一第二滴定步驟，以一第二滴定溶液與 與未反應之部分該第一滴定溶液（碘溶液）反應，並利用該鉑電 極量測一滴定終點電位，並停止該第二滴定步驟。在本實施 例中，所加入之該第二滴定溶液係為硫代硫酸鈉溶液。 參考步驟S17，根據所加入之該第一滴定溶液及該第二滴定 溶液之體積及濃度、該待測硫化物之當量值及該比例常數， ' 以該線上分析裝置計算得出該待測硫化物之含量（在本實施例 中，該待測硫化物係為硫化氫）。 在本實施例中，該待測煉焦廢水之該待測硫化物含量係以 下方程式（2)計算而得： 待測硫化物含量^JN^xN2V2)><Mxl〇〇〇x{比例常數）（2) 其中，川為第一滴定溶液之當量濃度；Vi為第一滴定溶液加 入量（mL) ; N2為該第二滴定溶液之當量濃度；V2為該第二滴 定溶液之終點消耗量（mL) ; Μ為硫之當量17 ; W為該樣品煉焦 參 廢水之體積（mL)。 圖2顯示本發明三組樣本煉焦廢水中之干擾性硫化物含量及 . 待測煉焦廢水中之實際硫化物含量示意圖。其中，曲線L11、 L12及L13係分別代表三組樣本煉焦廢水中之干擾性硫化物含 量變化曲線，其數值係對應至左側之縱座標；曲線L21、L22 及L 2 3係分別代表三組待測煉焦廢水中之實際硫化物含量變化 曲線，其數值係對應至右側之縱座標。 由圖2可知，在三組樣本煉焦廢水及待測煉焦廢水中，該實 際硫化物含量及該干擾性硫化物含量之比值約為1 : 10。該實 123107.doc -10- 200946903 際硫化物含量及該干擾性硫化物含量之比值，確實符合本發 明定義之該比例常數之範圍。 圖3顯示本發明待測煉焦廢水於二作業線上實際測得之硫化 物含量示意圖。其中，樣本煉焦廢水體積為20毫升；碘溶液 之當量濃度為0.1N、體積為6毫升；硫代硫酸鈉溶液之當量濃 度0.1N。另外，曲線L1及L2係分別代表二作業線上該待測煉 焦廢水中之硫化物含量變化曲線。由圖3可知，本發明之該待 測煉焦廢水於二作業線上所測得該硫化物含量係介於10-20 ppm(mg/L)，比較實際計算之硫離子含量，其偏差量皆小於 20%，符合一般線上分析偏差不大於30%之要求。 本發明之煉焦廢水硫化物含量之線上檢測方法，係以該銘 電極作為滴定電極，其不易受到煉焦廢水之其他雜質成分之 干擾，且該鉑電極可量測至極低之終點電位，故可準確地檢 測出煉焦廢水中硫化物之含量。並且，本發明之煉焦廢水硫 化物含量之線上檢測方法，可直接於線上檢測煉焦廢水中硫 化物之含量，故檢測方法簡單且快速。 上述實施例僅為說明本發明之原理及其功效，並非限制本 發明。因此習於此技術之人士對上述實施例進行修改及變化 仍不脫本發明之精神。本發明之權利範圍應如後述之申請專 利範圍所列。 【圖式簡單說明】 圖1顯示本發明煉焦廢水硫化物含量之線上檢測方法之流程 回 · 圖， 圖2顯示本發明三組樣本煉焦廢水中之干擾性硫化物含量及 123107.doc -11 - 200946903 待測煉焦廢水中之實際硫化物含量示意圖；及 圖3顯示本發明待測煉焦廢水於二作業線上實際測得之硫化 物含量示意圖。H2S+I2->2HI+S Next, a second reference titration step is performed, and a sodium thiosulfate solution is added to the iodine solution, the mixed solution of the hydrogen sulfide and the zinc sulfide solution, so that sodium thiosulfate and Part of the reaction reacts with iodine to form sodium iodide (Nal) and sodium sulfate 123107.doc 200946903 (Na2S406), and a reference titration end point potential is measured with a reference platinum electrode, and the second reference titration step is terminated, and the chemical reaction is terminated. The formula is as follows: 2Na2S2〇3+l2-> 2NaI+ Na2S4〇6 Finally, according to the volume and concentration of the iodine solution and the sodium thiosulfate solution added, and the equivalent value of the hydrogen sulfide, the sample is calculated to be coked. The actual sulfide content of the wastewater. Wherein, the second reference titration end point potential is 300 to 500 millivolts (mV). In the present embodiment, the actual sulfide content of the sample coking wastewater is calculated by the following equation (1): ^ A (msA (Λ^χΑΓ2Κ2)χΜχ1000 actual sulfide content I ^- ------ -(1) where, Sichuan is the equivalent concentration of iodine solution; 乂1 is the amount of iodine solution added (mL); N2 is the equivalent concentration of Na2S203 solution; V2 is the end point consumption of solution (mL); Μ is the strontium sulfide The value is 17; W is the volume (mL) of the coking wastewater of the sample. Referring to step S14, an on-line analysis device is provided, the on-line analysis device has a platinum electrode, and a coke wastewater to be tested is introduced into the on-line analysis device. The sulphur wastewater to be tested has a sulfide to be tested, and the sulfide to be tested has an equivalent value (in this embodiment, the equivalent value of hydrogen sulfide is 17). According to different applications, the platinum and the electrode are selectively selectable. The ground is a double platinum electrode. In this embodiment, the present invention presets a titration end point potential setting value to the analysis device, wherein the titration end point potential setting value is between 200 and 600 millivolts (mV), Preferably, the titration end point potential setting is between 300 Referring to step S15, performing a first titration step, adding a first titration solution to the coking waste water to be tested in the analytical device, and partially extracting the first titration solution and the sulfide to be tested The reaction is reduced to form sulfur. In the present embodiment, the first titration solution added by 123107.doc -9- 200946903 is an angstrom solution. Referring to step S16, a second titration step is performed to prepare a second titration solution. Reacting with the unreacted portion of the first titration solution (iodine solution), and measuring the titration end point potential by the platinum electrode, and stopping the second titration step. In this embodiment, the second titration is added. The solution is a sodium thiosulfate solution. Referring to step S17, according to the volume and concentration of the first titration solution and the second titration solution added, the equivalent value of the sulfide to be tested and the proportional constant, The on-line analyzer calculates the content of the sulfide to be tested (in the present embodiment, the sulfide to be tested is hydrogen sulfide). In this embodiment, the sulfur to be tested in the coking wastewater to be tested contains Calculated by the following equation (2): Sulfate content to be tested ^JN^xN2V2)><Mxl〇〇〇x{proportional constant) (2) where, Sichuan is the equivalent concentration of the first titration solution; Vi is The first titration solution is added in an amount (mL); N2 is the equivalent concentration of the second titration solution; V2 is the end consumption of the second titration solution (mL); Μ is the equivalent of sulfur of 17; W is the coking wastewater of the sample Volume (mL). Figure 2 is a graph showing the content of interfering sulfides in the three sets of sample coke wastewater of the present invention and the actual sulfide content in the coke wastewater to be tested. Among them, the curves L11, L12 and L13 represent the variation curve of interfering sulfide content in the three groups of coke wastewater, respectively, and the values correspond to the ordinate on the left side; the curves L21, L22 and L 2 3 represent three groups respectively. The actual sulfide content change curve in the coke wastewater is measured, and its value corresponds to the ordinate of the right side. It can be seen from Fig. 2 that the ratio of the actual sulfide content to the interfering sulfide content in the three sets of sample coking wastewater and the coking wastewater to be tested is about 1:10. The ratio of the sulphide content to the interfering sulphide content does meet the range of the proportionality constant as defined by the present invention. Fig. 3 is a view showing the content of sulfide which is actually measured on the second working line of the coking wastewater to be tested of the present invention. Among them, the sample coking wastewater volume is 20 ml; the iodine solution has an equivalent concentration of 0.1 N and a volume of 6 ml; and the sodium thiosulfate solution has an equivalent concentration of 0.1 N. In addition, the curves L1 and L2 represent the changes in the sulfide content in the wastewater to be tested on the two lines, respectively. It can be seen from FIG. 3 that the sulfide content of the coke-contaminated wastewater to be tested in the present invention is 10-20 ppm (mg/L) measured on the second line, and the actual calculated sulfur ion content is less than the deviation. 20%, in line with the general online analysis deviation of not more than 30%. The method for detecting the sulfide content of the coking wastewater of the present invention adopts the electrode as a titration electrode, which is not easily interfered by other impurity components of the coking wastewater, and the platinum electrode can be measured to a very low end potential, so that it can be accurately The content of sulfide in the coking wastewater was detected. Further, the on-line detection method of the sulfur content of the coking wastewater of the present invention can directly detect the content of sulfide in the coking wastewater on the line, so the detection method is simple and rapid. The above embodiments are merely illustrative of the principles and effects of the invention and are not intended to limit the invention. Therefore, those skilled in the art can make modifications and changes to the above embodiments without departing from the spirit of the invention. The scope of the claims of the present invention should be as set forth in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart showing the method for detecting the sulfide content of the coking wastewater of the present invention, and FIG. 2 is a view showing the content of interfering sulfide in the three groups of coke wastewater of the present invention and 123107.doc -11 - 200946903 Schematic diagram of the actual sulfide content in the coking wastewater to be tested; and Figure 3 shows a schematic diagram of the sulfide content actually measured on the second line of the coke wastewater to be tested of the present invention.
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