Chapter 10 Water Treatment and Hydration

Article 224. General provision

Purpose of water quality management is to preventscale buildup and corrosion etc. of boiler, steam turbine and auxiliaries due to water and steam quality and keep high efficiency of power plant at all times. Structure, temperature, pressure and operation status of power plant are different various ways. And, in recent years, efficiency of power plant is enhanced by high temperature, high pressure, increasing in size and combined cycle system and type of boiler operation is diversified byfluctuation of electric power supply-demand situation. Therefore, there is a possibilitythat trouble which power plant is stopped due to scale buildup and corrosion is caused if water quality of condensed water, feed water and boiler water are not managed strictly.Thus, water quality management is very important to maintain and enhance the reliability of power plant. It must beredreferto Article 142 of this guideline regarding sample of water quality management standard.

Article 225. Water treatment

It must be operated and maintained water treatment systemadequately to maintain water quality and operate power plant stably. Water treatment system of power plant is composed of feed water (make up water) treatment system, condensate demineralizerand chemical dosing equipment. And, it must be managed these equipments by daily patrol and inspection. Point to be checked at daily patrol and inspection is shown as follows;

1.Feed water treatment system

(1)It must be conducted daily patrol and inspection according to procedures developed by each power plant.

(2)Pump (Chemical injection pump, filtrate pump, purified water pump, waste water pump etc.)

1)Pump outlet pressure etc.

2)Abnormal noise, abnormal odor, vibration and leakage

3)Heating, abnormal noise and oil leakage for bearing

4)Level, change in color and leakage for lubricant oil

5)Leakage and corrosion of piping

6)Leakage and corrosion of valves

7)Corrosion and peeling for painting

(3)Tank (Purified water tank, chemical tank)

1)Level of purified water or chemical etc.

2)Leakage and corrosion of tank body

3)Leakage and corrosion of piping

4)Leakage and corrosion of valves

5)Corrosion and peeling for painting

(4)Tower (H-tower, OH-tower, vacuum degasifier tower)

1)Electric conductivity and silica concentration of H-tower and OH-tower outlet etc.

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2)Vacuum and water level of vacuum degasifier tower etc.

3)Leakage and corrosion of tower body

4)Leakage and corrosion of piping

5)Leakage and corrosion of valves

6)Corrosion and peeling for painting

Photo 225- 1 Feed-water treatment system

2.Condensate demineralizer

(1)It must be conducted daily patrol and inspection according to procedures developed by each power plant.

(2)Pump (Coil cooling water pump, makeup water pump, waste water pump etc.)

It must be referred to paragraph 1 of this article regarding pump of condensate demineralizer.

(3)Condensate polisher and electromagnetic filter

1)Sodium concentration and electric conductivity of condensate polisher etc.

2)Differential pressure and flow of electromagnetic filter etc.

3)Leakage and corrosion of condensate polisher and electromagnetic filter body

4)Leakage and corrosion of piping

5)Leakage and corrosion of valves

6)Corrosion and peeling for painting

(4)Tank (Chemical tank, resin tank, coil cooling water tank)

It must be referred to paragraph 1 of this article regarding tank of condensate demineralizer.

Photo 225-2 Condensate demineralizer

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3.Chemical dosing equipment

(1)It must be conducted daily patrol and inspection according to procedures developed by each power plant.

(2)Pump (Ammonia dosing pump, hydrazine dosing pump etc.)

It must be referred to paragraph 1 of this article regarding pump of chemical dosing equipment.

Photo 225-3 Chemical pump

(3) Tank (Ammonia tank, hydrazine tank)

It must be referred to paragraph 1 of this article regarding tank of chemical dosing equipment.

Article 226.

(Nothing)

Article 227. Safety for chemical agent

Equipment, devices and vehiclesmust be safe for loading, storing and transporting caustic soda,

Cough, sore throat, short breath

(2) Skin

Reddening, pain, burn injury, bulla

(3) Eye

Reddening, pain, bleary eyes, burn injury

(4) Oral intake

Stomach ache, burn injury, nauseous, vomit

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2.Ammonia

(1)Inhalation

Burning sensation, cough, feeling of smothering, sore throat, short breath

(2) Skin

Reddening, burn injury, pain, bulla, cold injury (in case of touching liquid ammonia)

(3) Eye

Reddening, pain, burn injury

3.Hydrazine

(1)Inhalation

Cough, burning sensation, headache, head trip, nauseous

(2) Skin

Reddening, pain, burn injury

(3) Eye

Reddening, pain, burn injury

(4) Oral intake

Burn injury, stomachache, diarrhea, vomit

Article 228. Wastewater treatment

Waste water quality management is different from quality management of boiler water and makeup water. It plays a major role in environmental protection of power plant. It must be treated all kinds of waste water properly and complied with waste water quality standard and agreement with local authority. Waste water is composed of steady waste water and unsteady one. Steady waste water is waste water which each equipment of power plant discharge continuously and by fits. Unsteady waste

water is waste water which discharges at periodic inspection.

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Table 228-1 Category of waste water

Photo 228-1 Wastewater treatment equipment

Article 229. Chemical analyses

Chemical analyses in power plant must satisfy the following content:

1.Corrosive and residue condition of water treatment and thermo equipment must be had thorough grasp on.

It must be checked corrosive and residue condition of water treatment and thermo equipmentat daily operation and inspection. It must be referred to Article 225 of this Guideline regarding point to be checked at daily operation and inspection.

2.Quality of water, steam, remaining salt, chemicals, organic fuel, ash, slag, gas and oil must be defined;

It must be checked quality of water, steam, remaining salt, chemicals, organic fuel, ash, slag, gas and oil during operation or periodic inspection to operate power plant safely and stably. It must be referred

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