Water Treatment preliminary learning

STANDARD SOLUTION PREPARATION:
1. N/50 EDTA SOLUTION: - 3.724 gm. OF ETHYLENE DIAMINE TETRAACETIC ACID DISODIUM SALT DISSOLVED IN 1000 ml DISTILLED WATER.
2. N/50 HCL SOLUTION: - 1.8 ml OF CONC. HCL MIXED WITH 1000 ml. OF DISTILLED WATER.
3. N/50 AgNO3 SOLUTION: - 3.398 gm. OF SILVER NITRATE DISSOLVED IN 1000 ml. OF DISTILLED WATER.
4. AMMONIA BUFFER SOLUTION: - 67.6 gm. OF AMMONIUM CHLORIDE AND 568 ml. OF AMMONIUM HYDRAUXIDE MIXED UP IN 1000ml. OF DISTILLED WATER.
5. ERIOCHROME BLACK T INDICATOR: - 0.25 ERIOCHROME BLACK T AND 0.25 gm OF HYDRAUXL AMMONIUM HYDROCHLORIDE DISSOLVED IN 50 ml ETHANOL.
6. PHENOPTHALEIN INDICATOR SOLUTON:- 0.25 gm OF PHENOPTHALEIN DISSOLVED IN 50 ml. OF WATER
7. METHYL ORANGE INDICATOR SOLUTION:- 0.1 gm. METHYL ORANGE DISSOLVED IN 100 ml. WATER
8. POTASSIUM CHROMATE SOLUTION :- 5 gm. OF POTASSIUM CHROMATE DISSOLVED IN 100 ml. OF DISTILLED WATER.
9. MUREDIX INDICATOR :- 0.5 gm. OF MUREDIX WITH 100 gm. NaCl
10. HCL SOLUTION :- 100 ml. HYDROCHLORIC ACID MAKE UP IN 100 ml. OF DISTILLED WATER.
11. 10% AMMONIUM MOLYBDATE SOLUTION :- 20 gm. AMMONIUM MOLYBDATE DISSOLVED IN 200 ml. DISTILLED WATER.
12. 10% OXALIC ACID SOLUTION:- 20 gm. OF OXALIC ACID DISSOLVED IN 200 ml. DISTILLED WATER.
13. A.N.S.A. SOLUTION:- 0.25 gm. AMINO NAPTHOL SULPHONIC ACID , 0.5 gm. SODIUMSULPHATE AND 8.25 gm. SODIUM META BI SULPHITE DISSOLVED IN 200 ml. DISTILLED WATER.
14. PHOSPHATE 1 SOLUTION:- 0.85 ml. NITRIC ACID 63 ml. SULPHURIC ACID AND 7.85 gm. AMMONIUM MOLYBDATE DISSOLVED IN 200 ml. DISTILLE WATER.
15. PHOSPHATE 2 SOLUTION:- 0.15 gm. AMINO NAPTHOL SULPHONIC ACID , 8.4 M. SODIUM SULPHITE & 14 gm. SODIUM META BI SULPHITE DISSOLVED IN 200ml. WATER
16. HCL SOLUTION:- 20 ml. CONC. HCL AND DISTILLED WATER 200 ml. MIX.
17. P-DIMETHYL AMINO BENZELDEHYDE SOLUTION :- 15 gm. PDAB DISSOLVED IN CONC. HCL AND MAKE UP WITH DISTILLED WATER UP TO 500ml.

INDICATIVE TYPICAL WATER QUALITY PARAMETES;


PARAMETERS
RAW WATER
SOFT WATER
D.M.WATER

Ph
7.8- 8.0
7.8-8.0
6.8-7.2

CONDUCTIVITY
1000-1100
1000-1100
< 1

TDS IN ppm
670-750
670-750
< 1

TOTAL HARDNESS AS CACO3 IN ppm
250-300
0-50
NOT DETECTABLE

CALCIUM HARDNESS AS CACO3 IN ppm
200 MAX
35 MAX
NOT DETECTABLE

MAGNESIUM HARDNESS AS CACO3 IN ppm
100 MAX
10 MAX
NOT DETECTABLE

TURBIDITY IN NTU
<1
<1
<1

P ALKALINITY AS CACO3 IN ppm
NIL
NIL
NIL

M ALKALINITY AS CACO3 IN ppm
200- 220
200-220
NIL

CHLORIDE AS CACO3 IN ppm
250-300
250-300
NIL

SILICA AS SIO2 IN ppm
5-10
5-10
<0.02






ABOVE PARAMETERS ARE INDICATIVE ONLY IT WILL VARY PLACE TO PLACE AND SOURCE OF WATER. .WATER QUALITY PARAMETERS ARE TO BE CHECKED BEFORE DECIDING WATER TEATMENT PROCESS SELECTION AND APPLIATION OF SUITABLE TECHNOLOGY





THE PROCESS OF DEMINERALISATION:

THE MOST BASIC PROCESS OF DEMINERALISATION THROUGH ION EXCHANGE IS TWO STAGE DEMINERALISATION . THE FIRST STAGE IS REMOVAL OF CATION FOLLOWED BY REMOVAL OF ANIONS.
THE CATION EXCHANGE UNIT CONTAINS A STRONG ACID CATION EXCHANGER IN A REGENERATED FORM. THE EXCHANGER TAKES UP CATIONS IN WATER IN EXCHANE OF HYDROGEN IONS WHICH IT GIVES UP .

THE CATIONS LIKE CALCIUM, MAGNESIUM, AND SODIUM EXIST IN THE FORM OF CHLORIDE, SULPHATE CARBINATE AND BICARBONATE SALTS WHICH GETS CONVERTED TO THEIR EQUIVALENT ACIDS.

CHEMICAL REACTION

NACL + RH = R NA + HCL
SODIUM HYDROGEN SODIUM
CHLORIDE EXCHANGER EXCHANGER

MGSO4 + RH = R2 MG + H2SO4
MAGNESIUM HYDROGEN MAGNESIUM
SULPHATE EXCHANGER EXCHANGER

CA(HCO3) + RH = R2CA + H2CO3
(CO2+H20)



RENEGERATION

RNA + HCL = RH + NA, CA MG CHLORIDESALTS
RCA + H2SO4 = RH + NA, CA MG
SULPHATE
SODIUM, MAGNESIUM, ACID
CALCIUM EXCHANGER






ANION EXCHANGE

HCL + ROH = RCL + H20
HYDRAUXIL CHLORIDE
EXCHANGER EXCHANGER
H2SO4 + ROH = R2SO4 + H20
HYDRAUXIL
EXCHANGER

REGENERATION

RCL + NAOH = ROH + NACL

R2SO4 + 2NAOH = 2ROH + NA2SO4


CARBONATES /BICARBONATES IN THE CATION EXCHANGE PROCESS ARE CONVERTED TO CARBONIC ACID WHICH DISSOCIATES AS IT IS A WEAK ACID, INTO CABONDIOXIDE AND WATER. THIS CARBON DIOXIDE IS REMOVED BY DEGASSED AIR. OTHERWISE IT WOUL BE ABSORBED BY THE STRONG BASE ANON EXCHANGER.
THE STRONG ACID CATION, WEAK BASE ANION,AND STRONG BASE ANION EXCHANGERS ARE REGENERATED WITH SPECIFIC QUALITIES OF ACID AND ALKALI.TO GET A SPECIFIC EXCHANGE CAPACITY . WHEN THIS CAPACITY IS EHAUSTED THE QUALITY OF TREATED WATER DETERIORATES, POINTING TO THE NEED FOR REGENERATION.

WATER SOFTENING

WHEN RAW WATER PASSES THROUGH THE ION EXCHANGE WATER SOFTENER CALCIUM AND MAGNESIUM IONS IN THE RAW WATER ARE EXCHANGED FOR SODIUM IONS.
THERE IS NO DESCREASE IN THE TOTAL DISSOLVED SOLIDS CONTENT OF THE TREATED WATER.
THERE IS NO CHANGE IN THE PH OR TOTAL ALKALINITY CONTENT.
THE SPECIFIED OUTPUT OF THE SOFTENER IS BASED ON SPECIFIED RAW WATER HARDNESS, IF THERE IS AN INCREASE IN RAW WATER HARDNESS THERE WILL BE A PROPORTIONATE DECREASE IN CAPACITY.
THE RAW WATER HARDNESS MUST BE CHECKED PERIODICALLY.
TREATED WATER HARDNESS MONITORING IS REQUIRED AT THE END OF THE RINSE