hach水质常规分析(COD、氨氮、SS、总磷、色度)

Safety Good safety habits and laboratory techniques should be used throughout the procedure. Consult the Material Safety Data Sheets for information specific to the reagents used. For additional information, refer to Section 3.
干扰物质最大允许含量及消除干扰的办法 将水样的 pH 值调节至中性：对于酸性水样，加入 1N 的氢 氧化钠；对于碱性水样，加入 1N 的盐酸 最大允许含量 50,000 mg/L，以 CaCO3 计 会导致被测水样的颜色加深 最大允许含量 300,000 mg/L，以 CaCO3 计 可以按照以下步骤扣除铁的干扰： 3. 测量水样中总铁的含量 4. 在第 4 步操作之前，在空白溶液中加入同样浓度的铁 最大允许含量 600 mg/L，以 NO2－N 计 最大允许含量 5,000 mg/L，以 NO3－N 计 最大允许含量 5,000 mg/L，以 PO4－P 计 最大允许含量 5,000 mg/L，以 SO4 计 硫化物会导致产生过深的颜色，可以按照以下步骤扣除硫 化物的干扰： 5. 在 500mL 厄氏容量瓶中，加入 350mL 待测水样； 6. 加入一份硫化物抑制试剂(Hach #2418-99)，摇匀 用滤纸(Hach #692-57)过滤待测水样， 会导致测量结果偏高。如果干扰过大，建议对水样先进行 蒸馏，可以采用 HACH 公司的通用蒸馏用装置 。
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Method Performance Precision In a single laboratory, using a standard solution of 50 mg/L ammonia nitrogen (NH3-N) and two representative lots of reagent with the instrument, a single operator obtained a standard deviation of +5 mg/L NH3-N. Estimated Detection Limit The estimated detection limit for program 67 is 1 mg/L NH3-N. For more information on the estimated detection limit, see Section 1.
所需试剂
AmVer.氨氮试剂一套, TNT (25 tests) ……………………………………................26069-45
包括: (1) 23952-66, (1) 23954-66, (1) 272-42, *(50) AmVer HR Vials
所需数量
试剂种类
每次测试
单位
货号
Summary of Method Ammonia compounds combine with chlorine to form monochloramine. Monochloramine reacts with salicylate to form 5-aminosalicylate. The 5-aminosalicylate is oxidized in the presence of a sodium nitroprusside catalyst to form a blue-colored compound. The blue color is masked by the yellow color from the excess reagent present to give a green-colored solution.
7．盖紧瓶盖。大力摇 晃是粉末完全溶解。
注：如果氨存在，溶 液将呈现绿色。
8．按下： TIMER ENTER
将开始 20 分钟的反 应计时。
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9．用布擦干瓶外壁。 10．按 ZERO，指针将 计时器鸣响后，将空 右移，屏幕显示： 白试样放入样品适配 0.00 mg/L NH3-N 器中，盖紧遮光盖。
试管架 ……….............................................................. 1-3 ...................个................18641-00
漏斗 .................................................................................1 ….................个.................25843-35
Accuracy Check Standard Additions Method a) Snap the top off an Ammonia PourRite Ampule Standard, 150 mg/L NH3-N. b) Use the TenSette Pipet to add 0.2, 0.4 and 0.6 mL of standard to three 25-mL samples. Swirl to mix. c) Analyze each sample as described above. The ammonia concentration should increase approximately 1.2 mg/L NH3-N for each 0.2 mL of standard added. d) If these increases do not occur, see Standard Additions in Section 1 for more information. Standard Solution Method To check accuracy, use a 10 or 50 mg/L Nitrogen, Ammonia Standard Solution or use a Nitrogen, Ammonia Voluette Ampule Standard, 50 mg/L.
氨水氰尿酸盐粉末试剂 ……………………........ 2 包 .................50/pkg ..........239适配器...........................................................1 .....................个.................48464-00
Sampling and Storage Collect samples in clean plastic or glass bottles. Best results are obtained with immediate analysis. If chlorine is known to be present, add one drop of 0.1 N sodium thiosulfate for each 0.3 mg/L Cl2 in a one liter sample. Preserve the sample by reducing the pH to 2 or less with hydrochloric acid (at least 2 mL). Store at 4 ¡ãC (39 ¡ãF) or less. Preserved samples may be stored up to 28 days. Before analysis, warm samples to room temperature and neutralize with 5.0 N sodium hydroxide. Correct the test result for volume additions.
Pollution Prevention And Waste Management The ammonia salicylate reagent contains sodium nitroferricyanide. Cyanide solutions are regulated as hazardous wastes by the Federal RCRA. Collect cyanide solutions for disposal as reactive (D001) waste. Be sure cyanide solutions are stored in a caustic solution with pH >11 to prevent release of hydrogen cyanide gas. See Section 3 for further information in proper disposal of these materials.
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OPTIONAL REAGENTS
Nitrogen, Ammonia Standard Solution, 50 mg/L NH3-N ..................... 500 mL ..........14791-50
Nitrogen, Ammonia Standard Solution, 10 mg/L NH3-N ..................... 500 mL ..............153-49
氨氮 水杨酸法 低量程 (0 to 50 mg/L NH3-N)
Test ‘N Tube
方法号：10031
1.输入检测高量程氨
氮Test‘N Tube的
程序编号。 按下：PRGM 屏幕将显示：
PRGM？
2．按下：67 ENTER 屏幕将显示： 0.00 mg/L、 NO3-N 和ZERO图标。
注：如检测其他形态 的氮(NH3)， 按下： CONC