WATER CYCLE IN THERMAL POWER PLANTS

VARIOUS WATER QUALITIES INSIDE THERMAL POWER PLANT

• COOLING WATER (BCW,ACW)• BOILER WATER• CONSUMPTIVE WATER

WATER TREATMENT

• PRE-TREATMENT OF RAW WATER• FILTER WATER FOR SOFTENING AND DM

PLNAT• DM WATER FOR BOILER

WHY AND HOW

• The purpose of a water treatment program is to provide heat-exchange surfaces that are sufficiently intact and free of deposits so that design specifications are met. At KSTPS suspended and soluble water impurities are removed with the help of PAC (Poly Aluminium Chloride) while treatment of organic impurities at raw water & circulating cooling water is being carried out with the help of Liquid Chlorine.

WATER FLOW DIAGRAM

CLARIFLOCULATOR

GRAVITY FILTER

U/G STORAGE

TANK

BOILER MAKE

UP

DM PLNAT

RAW WATER

DRINKING WATER

BCW MAKE

UP

SOFTENING PLANT

DM PLANT

For removal of Total Dissolved solids such as Ca, Mg, Na,Cl,So4, Alkalinity, Silica etc.

ACF

WEAK BASE

ANIONDEGASSER

STRONG ACID

CATION

STRONG BASE

ANION

MIXED BED

DM STORAGE WATER TANK

UCFT

COOLING WATER

• TO AVOID SCALE FORMATION• TO CONTROL CORROSION• TO CONTROL MICRO BIOLOGICAL GROWTH• TO CONTROL VACUUM IN CONDENSER

VARIOUS COOLING WATER SYSTEMS

• ONCE THROUGH COOLING WATER SYSTEM• OPEN RECIRCULATION COOLING SYSTEM• CLOSED CYCLE COOLING WATER SYSTEM

pH• pH is a measure of how acidic/basic water is. • The range goes from 0 - 14, with 7 being neutral. pHs

of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.

• pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water. Water that has more free hydrogen ions is acidic, whereas water that has more free hydroxyl ions is basic.

• pH is reported in "logarithmic units. Each number represents a 10-fold change in the acidity/basicity of the water. Water with a pH of five is ten times more acidic than water having a pH of six.

Importance of pH

• The pH of water determines the solubility (amount that can be dissolved in the water) and biological availability (amount that can be utilized by aquatic life) of chemical constituents such as nutrients (phosphorus, nitrogen, and carbon) and heavy metals (lead, copper, cadmium, etc.).