鈉的測定翻譯（PNa電極法）-中英對照
1、概述：用PNa電極和甘汞參比電極浸入被測水樣中，組成電極對，PNa電極的電位隨液中鈉離子的活度而變化，用DWS—51型鈉度計即可測出鈉離子的含量。
PNa=-lg[Na+]
2、測定方法
（1）接通電源，儀器預熱半小時。
（2）調零：溫度補償和刻度“校正”。
（3）定位：定位和復定位誤差不超過±0.02至±0.03PNa（定位液PH要調至10以上）。
 （4）水樣測定：用二異丙胺調PH為10以上的好水清洗電極，洗至PNa值大于6.5以上然后用調過PH的水樣進行測定，取穩定值。

五．  磷酸根的測定
1、概述：
在0.6N酸度下,磷酸鹽與鉬酸銨生成磷鉬黃,用氯化亞錫還原成磷鉬蘭后，與同時配制的標準色進行比色測定，反應如下。
  PO43-+12Mo2-+27H+→H3[P（Mo3O10）4]+12H2O
                              （磷鉬黃）
[P（Mo3O10）4]3-+11H++4Sn2+→H3[P（Mo3O9）4]+4Sn4+4H2O
2、測定方法：
（1）量取0.2、0.5、0.7、0.9、1.1、1.3毫升磷酸鹽工作液（1ml=0.025mgPO43-）及水樣2.5ml，分別注入一組比色管中，用好水稀釋約20ml，搖勻。
（2）于上述比色管中加入3.5ml硫酸—鉬酸銨混合液，用好水稀釋至刻度，搖勻。
（3）于每支比色管中加入5滴氯化亞錫溶液搖勻，待3分鐘后進行比色。PO43-按下式計算：

PO43-
   a：與水樣顏色相當的標準中加入PO43-工作液體積，毫升；
V：水樣體積。
六．  溶解氧的測定（靛藍二磺酸鈉葡萄糖比色法）
概要
（1）在PH為12.5左右時，靛藍二磺酸鈉葡萄糖還原成淺黃色的還原物。當其與水中溶解氧相遇時，即與溶解氧反應產生紅色半靛醌中間產物。此中間產物在有溶解氧的情況下，還會繼續被氧化成為藍色的靛藍二磺酸鈉。
（2）在高堿性的情況下，還原型靛藍二磺酸鈉在氧化過程中會出現紅色半靛醌中間產物，因此就大大提高了在溶解氧測定過程中各色階的變化范圍，更有利于目視比色的測定。其色澤的變化范圍為淺綠黃色、黃色、桔紅色、紅色、絳紅色、紫色、藍色，最后為藍綠色。
（3）由于有副反應，因此在中間階段的變色范圍內，根據在測試中條件的不同（例如試劑批號、分析時水溫以及水樣中雜質等因素），會出現所發生的色澤與標準色階不甚匹配的現象。本法的測定范圍為0~100ug/L，假色標準還可擴大至160ug/L。其中以0~20以及50~100ug/L區間為最靈敏。
試劑
（1）靛藍二磺酸鈉貯備液。
（2）葡萄糖貯備溶液。
（3）氫氧化鉀溶液。
（4）靛藍二磺酸鈉葡萄糖溶液：量取上述靛藍二磺酸鈉和葡萄糖貯備溶液各5ml，氫氧化鉀溶液5ml，加水10ml，充分混合后，立即注入25ml滴定管內，并用礦物油作油封。使其充分變成檸檬黃色后使用，時間通常為1 ~2小時。
3、測定方法
（1）標準色的配制。
瓶號 溶解氧含量 溶液顏色
1 0.000 黃帶綠色
2 0.005 微綠黃色
3 0.010 橙黃色
4 0.015 橙黃帶紅色
5 0.020 粉紅色
6 0.025 桔紅色
7 0.030 紅色
8 0.035 絳紅色
9
0.040 絳紅色
10 0.050 絳紅微紫
11 0.060 紅紫色
12 0.070 淺紅紫色
13 0.080 紫色
14 0.100 深紫色
（2）水樣的測定：用1只125mL的專用溶氧瓶取樣，然后迅速加入1.0mL還原型靛藍二磺酸鈉葡萄糖工作溶液，立即塞緊瓶蓋，放置1~2min，立即在自然光或白色日光燈下，以白色作背景，同標準色進行比較。
注：①按規定的加藥量，最后水樣的PH值為12.0～12.5的規定。
②由于本方法是在較高的PH條件下測定的，因此如水樣中含有較多的鈣、鎂、鐵等金屬離子時，由于會產生沉淀，均不宜采用此方法。
③由于所配試劑堿性較大，當用堿式滴定管情況下，如較長時間不用或出現活塞有滲漏時，應將管內剩余試劑放掉，并用蒸餾水沖洗干凈。必要時再擦上潤滑脂，以防活塞固死。
④顯色后水樣堿性很大，應盡量避免同皮膚接觸，每次測試完畢后，應立即用清水將手沖洗干凈，以免侵蝕皮膚。
⑤靛藍二磺酸鈉葡萄糖工作溶液配好后，如室溫較高，放置時間可以短些。但最好是隔夜配好，并放置于陰冷處。否則，如還原反應未完全，工作溶液尚未完全變成淺黃色，則所測結果會大大偏高。
VI．Acid Rinsing:
On electrolyzing seawater, it is unavoidable to generate precipitates as calcium and magnesium besides sodium hypochlorite and hydrogen gas, which accumulate on the cathode of the electrolytic cell, resulting in the increase of cell voltage, the decrease of current efficiency and the growth of power consumption as well. Therefore, it is necessary to do some acid rinsing to the electrolytic cell regularly so as to remove the precipitates on the surface of cathode. At this moment, PLC is used to analyze the running time and the abnormality of cell voltage in order to judge if acid rinsing is required. Giving alarming signal during acid rinsing and light warning on the panel of control cabinet is necessary for acid rinsing. During the course of acid rinsing, the generator will be locked till the acid rinsing is completed, which shall be unlocked automatically for standby after it. 
 Operation mentioned above does not need disassemble any equipment or pipeline and do no harm to operators.

Section two  Working Principle and Technical Specification of Main Equipment
I. Seawater Booster Pump:
 The seawater booster pump selects Dalian Acid-resistant Pump, LH vertical type   single-stage and single-suction submergible pump, 3 sets. The model: LH50—400; the flow rate: 34m3/h; the pressure: 0.35 MPa; the axial length: 4.5m; the axle, axle sleeve and impeller of the seawater booster pump are all made of 316L stainless steel form abroad. The bearing of vertical long-axle submerged pump is an inlet one; the motor speed is 1450r/min.

II．Automatic Backwashing Filter:
1．Working Principle:
Automatic backwashing filter utilizes the pressure difference of system to implement backwashing without any influence on flowing of seawater and no special cleaning fluid is required during the cleaning process. In the normal operation, crude seawater runs into sieve through the inlet of filter, all impurities with diameter larger than 0.5mm will be retained on the sieve. This process carries on until the impurities accumulate to a certain degree, which causes the increase of pressure difference, when the pressure differential controller achieves the preset value（0.035Mpa）, automatic backwashing starts up. Sliding seal plate connected to the backwashing outlet will clean each part of sieve effectively. The internal pressure in the filter shell is higher than that of backwashing outlet pipe, thus some seawater flows in an opposite direction through sieve and cleans all accumulated impurities effectively, discharging them into trench through the blowdown valve.
The whole process is carried out by the differential pressure controller automatically. After all sieves of filters were cleaned, the automatic backwash cycle stops, and filters restore to the normal mode till next action of the pressure controller takes place, washing repeatedly.
2．Characteristics of Equipment:
- It is unnecessary to shut down during backwashing and the water consumption for backwashing is quite low.
 Backwashing adopts small and light motor with low power for convenience of maintenance. 
● The lid of filter shall be easily disassembled for maintenance of the sieve,
● Unique structure of sieve prevents from being blocked by impurities with strong anti-mechanical wear and anti-scour abilities.
● The possibility of damage is eliminated due to the separation of sieve and backwashing components.
● The import 316L stainless steel has strong anti-corrosion ability to seawater and longer service life.
● The low inertia of backwashing components ensures the minimum power consumption.
 ● The blowdown valve adopts an electric ball valve, which opens automatically during backwashing and closes after it.

3．Equipment Specification:
 ZHG56-LA Automatic Backwashing Filter, water treatment capacity is 68m3/h.

III．Sodium Hypochlorite Generator:
1．Working Principle:
The seawater that passes through the electrolytic cell shall be electrolyzed at both anode and cathode with chemical reactions as below: 
Anodic reaction：    2Cl—2e→Cl2                                    （1）
Cathodic reaction：   2H2O+2e→2OH-+H2↑                            （2）
Reaction between electrodes of electrolytic cell:   Cl2+ 2NaOH→2NaClO+H2↑ （3）
 Hypochlorous acid and hypochlorous acid ion are all called effective chlorine, and prevention of sea biological defile is realized by using effective chlorine which is generated from electrolyzing seawater.

2．Characteristics of Equipment:
 Lid of electrolytic cell: the lid is made of UV-resistant organic glass which is transparent so that the operator is able to directly observe chemical reactions in the cell through the lit during operation which is helpful for operators to judge and master maintenance of electrolytic cell and time of acid rinsing well.

Shell of electrolytic cell: the shell is made of PVC with perfect corrosion resistance to the sodium hypochlorite. This material possesses features of high strength, anti-aging and corrosion resistance compared with other materials with higher safety and stability, eliminating the leakage of liquid. 

2013.7.11