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1. P-ALKALINITY:- THIS TEST IS CARRIED TO FIND OUT THE PRESENCE OF ALKALINE IN BOILER WATER. BOILER WATER SHOULD BE ALKALINE TO SAVE IT FROM CORROSION.ALKALINITY IS DUE TO HYDROXIDE AND CARBONATES AND HYDROXIDE. P ALKALINITY IS USED TO FIND OUT ALKALINITY DUE TO CARBONATES. “P” STANDS FOR PHENOLPHTHALEIN ALKALINITY. PHENOLPHTHALEIN IS LESS ALKALINE THAN HYDROXIDE AND CARBONATES, HENCE IT GIVES OUT ITS COLOR. 

TEST PROCEDURE:-

A) ADD 100ML OF BOILER WATER+10 DROPS OF PHEONOLPHTHALEIN. IF HYDROXIDE OR CARBONATES ARE THERE THEN IT WILL TURN PINK.

B) THEN ADD N/50 H2SO4. IF PINK COLOR VANISHES THEN IT MEANS HYDROXIDE AND CARBONATES BOTH ARE PRESENT.

C) CALCULATION:-   ML OF N/50 H2SO4 *10= PPM OF CaCO3

2. T-ALKALINITY:- IS USED TO FIND ALKALINITY DUE TO BICARBONATES.

TEST PROCEDURE:-

A) TO THE SAMPLE OF P-ALKALINITY ADD 10 ML METHYL ORANGE. IF NO YELLOW COLOR APPEARS THEN NO BICARBONATES ARE PRESENT.

B) IF YELLOW COLOR APPEARS THEN ADD N/50 H2SO4 TILL COLOR VANISHES.

C) CALCULATION :-   ML OF N/50 H2SO4 USED *10= PM OF CaCO3

3. CHLORIDE TEST:- IS CARRIED OUT TO FIND OUT PRESENCE OF CHLORINE IN BOILER WATER WHICH CAN LEAD TO CORROSION. CHLORINE PRESENCE IN BOILER WATER MEANS INGRESS OF SEA WATER IN BOILER WATER MOST PROBABLY FROM DUMP/VACUUM CONDENSER.

TEST PROCEDURE:-

A) P-ALKALINITY SAMPLE+ 2ML H2SO4.

B) THEN ADD 20 ML POTASSIUM CHROMATE.

C) THEN ADD N/35.5 AgNO3 UNTIL BROWN COLOR APPEARS.

NOTE:-  AgNO3 HAVE THE AFFINITY FOR CHLORINE. WHEN IT NEUTRALIZES CHLORINE THEN IT REACT WITH CHROMATE AND GIVE REDDISH BROWN COLOR.

4. PHOSPHATE TEST:–  IS CARRIED OUT TO FIND THE CONCENTRATION OF PHOSPHATE IN BOILER WATER WHICH HELPS IN MAKING SLUDGE IN BOILER WATER NON ADHERENT AND HENCE EASY TO REMOVE.

TEST PROCEDURE:-

A) 25 ML FILTERED SAMPLE OF BOILER WATER+ 25 ML OF VANADOMOLYBDATE REAGENT.

B) LEAVE IT FOR 3 MINUTES. AND COMPARE WITH COLORED TUBES.

5. TOTAL DISSOLVED SOLIDS:-

TEST PROCEDURE:-

A) COOL BOILER WATER TILL ROOM TEMP. AND ADD PHENOLPHATHALEIN AND H2SO4 TILL PINK COLOR DISAPPEAR.

B) PLACE CONDUCTIVITY METER WITH TEMP OF WATER SET. CONDUCTIVITY READING NOTED.

C) CALCULATION:-  TDS= CONDUCTIVITY READING*0.7

6. HYDRAZINE TEST:– THIS TEST IS CARRIED OUT TO FIND OUT RESERVE HYDRAZINE IN BOILER WATER WHICH IS AN OXYGEN SCAVENGER. RESERVE SHOULD BE BETWEEN 0.1-1 PPM.

TEST PROCEDURE:-

A)TAKE  250 ML OF COOLER BOILER WATER SAMPLE, 15 ML OF N/2 HCL AND 2 NESSLERS CYLINDERS.

B) IN 1ST CYLINDER ADD 25 ML SAMPLE AND THEN ADD 4-DIMETHYLAMINOBENZALDEHYDE.

C) IN 2ND CYLINDER ADD 35ML OF WATER.

D) MATCH SAMPLE AGAINST DISC COLOR.

CALCULATION:- DISC READING/25= PPM OF HYDRAZINE