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Water & Wastewater Treatment
Filtration, ion exchange and RO for boiler make-up and industrial water, plus plant wastewater treatment
Process
Water treatment
- Raw
- In process
- Product
- Brine & waste
- Chemical
01Raw water tank
Stores the incoming raw water and sends it to the following process at a steady flow. The feed pump starts and stops according to the water level.
Main components
- Storage tank
- Level gauge
- Outlet piping and valve
- Overflow pipe
02Auto backwash filter
A screen element removes coarse particles such as sand and debris from the raw water to protect the UF membranes that follow. When the pressure difference across the screen rises, the filter backwashes itself without stopping operation and flushes out the trapped debris.
Main components
- Filter housing
- Screen element
- Backwash valve
- Differential pressure gauge
03UF
Hollow-fibre membranes remove the fine particles and colloids from the strained water, protecting the ion exchange resin downstream. They are backwashed regularly and cleaned with chemicals when needed.
Main components
- UF modules
- Upper and lower headers
- Rack frame
- Automatic valves
04Cation exchanger
Hydrogen-form cation resin exchanges cations such as calcium, magnesium and sodium for hydrogen ions. The carbonic acid formed in the water is removed in the degasifier that follows. When the resin is exhausted it is regenerated with acid.
Main components
- Rubber-lined pressure vessel
- Cation exchange resin
- Upper and lower distributors
- Valve nest
05Degasifier
Water from the cation exchanger trickles down the tower against air blown in from below, stripping out dissolved carbon dioxide. This reduces the ionic load on the anion exchanger and the amount of regenerant it needs.
Main components
- Tower shell
- Packing
- Water distributor
- Blower
06Anion exchanger
Hydroxide-form anion resin exchanges anions such as chloride, sulphate and silica for hydroxide ions, which combine with the hydrogen ions from the cation exchanger to form water. When the resin is exhausted it is regenerated with caustic soda.
Main components
- Pressure vessel
- Anion exchange resin
- Upper and lower distributors
- Valve nest
07Mixed-bed exchanger (MBE)
Cation and anion resins mixed in one vessel remove the last traces of ions. For regeneration the two resins are separated by backwashing, using their difference in density, and regenerated with acid and caustic soda respectively.
Main components
- Pressure vessel
- Mixed resin bed
- Middle collector
- Sight glass
08Regenerant tanks (acid, caustic)
Stores the acid and caustic soda used to regenerate the ion exchange resins. The tanks stand inside a bund wall in case of leaks, and their material is chosen to suit each chemical.
Main components
- Chemical tanks
- Bund wall
- Level gauge
- Regeneration ejector
09Demineralized water tank
Stores the demineralised water and sends it on, for example as boiler make-up. The vent may carry an absorber so that carbon dioxide from the air does not dissolve into the water.
Main components
- Storage tank
- Level gauge
- Vent
- Outlet piping and valve
Wastewater treatment
- In process
- Product
- Brine & waste
01Equalization tank
Collects the plant wastewater and evens out changes in flow and quality. A steady flow to the following process keeps treatment performance stable.
Main components
- Concrete tank
- Submersible pumps
- Mixing equipment
- Level gauge
02Coagulation and neutralization tank
Acid or alkali adjusts the pH, and coagulant is mixed in so that fine particles and heavy metals gather into flocs. The flocs settle out in the clarifier that follows.
Main components
- Reaction tank
- Agitator
- pH meter
- Chemical dosing line
03Clarifier
Settles the flocs and separates clear supernatant from sludge. Inclined plates increase the settling area, and the sludge collected at the bottom is drawn off to the dewatering equipment.
Main components
- Clarifier
- Inclined plates
- Overflow trough
- Sludge draw-off line
04Bioreactor (aeration tank)
Air blown in through diffusers on the floor lets microorganisms break down the organic matter in the wastewater. Blowers supply the air, and surplus biomass is drawn off as excess sludge.
Main components
- Concrete basin
- Diffusers
- Blowers
- Air piping
05Sand filter
Media beds of anthracite and sand remove the suspended solids and turbidity left after biological treatment and settling. Two units are installed and backwashed in turn when the pressure difference rises.
Main components
- Two pressure vessels
- Inlet distributor
- Media bed (anthracite, sand)
- Underdrain
06Activated carbon filter (ACF)
Activated carbon adsorbs the organic matter, colour and odour left in the sand filter effluent. It is the last filtration step for meeting discharge limits or reuse quality, and two units are installed for alternate operation.
Main components
- Two pressure vessels
- Activated carbon bed
- Inlet distributor
- Underdrain
07Discharge and reuse
Stores the treated water before it is discharged or reused as process water. Water quality is measured and recorded before discharge.
Main components
- Treated water tank
- Level gauge
- Water quality analysers
- Discharge line
Selected deliveries
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01Daelim Industrial · 2,200 m³/day · boiler make-up water -
02POSCO E&C · 960 m³/day · boiler make-up water -
03Doosan Heavy Industries · 5,760 m³/day · boiler make-up water -
04Doosan Heavy Industries · 4,320 m³/day · boiler make-up water -
05Doosan Heavy Industries · 4,800 m³/day · boiler make-up water -
06Doosan Heavy Industries · 5,280 m³/day · boiler make-up water -
07Doosan Heavy Industries · 1,152 m³/day · boiler make-up water -
08Doosan Heavy Industries · 1,152 m³/day · boiler make-up water -
09Doosan Heavy Industries · 7,200 m³/day · boiler make-up water -
10Kolon E&C · 3,600 m³/day · industrial water -
11Kolon E&C · 3,600 m³/day · industrial water -
12Daelim Industrial · 5,300 m³/day · boiler make-up water -
13ITT Water & Wastewater Korea · 27,000 m³/day · drinking water -
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Water and wastewater treatment plants produce boiler make-up water, industrial water and drinking water for power plants and industrial plants, and treat the wastewater those plants discharge. Depending on the source water and the required quality, we combine sand filtration, ACF (activated carbon filters), ion exchange (cation, degasifier, anion and MBE), RO and EDI.
We have delivered wastewater treatment systems to Korean industrial plants including Samsung Fine Chemicals (2003, 1,100 m³/day), Kolon E&C (2003, 1,200 m³/day) and Haitai Confectionery's Hayang plant (2004, 600 m³/day). For overseas power plants we supplied a wastewater treatment system for the Alcatrana power plant (LOTTE ENGINEERING, 2010) and a water and wastewater treatment system with clarifier, DMF, ACF, RO and EDI for the Puerto Bravo power plant (POSCO E&C, 2014, 960 m³/day).
For overseas power plants we delivered demineralized water systems for boiler make-up under Doosan Heavy Industries (now Doosan Enerbility): the Fujairah water and power plant in the UAE (2001, 7,200 m³/day), the Sohar power and water plant in Oman (2005, 5,280 m³/day) and the Qatalum combined cycle plant in Qatar (2008, 4,320 m³/day). In Korea we delivered a 27,000 m³/day MF system for the Muju and Geumsan water purification plants (ITT Water & Wastewater Korea, 2011).