Technical overview of

DEWATS Modules

Technical overview

Septic tank / SettlerAnaerobic Baffled Reactor

Biogas settler

Anaerobic FilterPlanted Gravel Filter

Pond Systems

OR

Technical overview

Septic tank / settler

• Consists of min. 2 to 3 compartments

• Settling / sedimentation tanks for retaining particle

• Outlet is free from settleable solids

• Dissolved & suspended matter passes untreated to next treatment stage

• Efficiency 25% to 40%

• Desludging period 1 to 3 yrs - depends on sludge storage

Technical overview

Biogas settler

• Sedimentation tanks for retaining particles

• Biogas is formed due to digestion of settled organic matter in anaerobic condition

• Outlet is free from settleable solids

• Dissolved & suspended matter passes untreated to next treatment stage

• Efficiency 25% to 40%

• Desludging period 1 to 3 yrs, depending on sludge storage

• Biogas production: Gas storage is needed (gas tight)

Technical overview

Anaerobic baffle reactor

• Treatment in absence of oxygen (anaerobic)

• Wastewater passes through a series of chambers in up-flow form

• Sludge (activated) at the bottom of each chamber

• Further treatment (degradation) of suspended & dissolved solids by available bacteria

• Efficiency 75% to 85%

• Desludging needed only if excess sludge (activated) is generated

Technical overview

Anaerobic fixed bed filter

• Treatment occurs in absence of oxygen (anaerobic)

• Wastewater passes in a series of chambers through the filter material in up-flow form

• Filter is made out of gravel, slag or plastic elements

• To avoid plugging pre-treatment (sedimentation) is necessary

• Efficiency 75% to 90%

• Desludging is needed only if excess sludge (activated) is generated

Technical overview

Planted gravel filter

• Treatment occurs in presence of oxygen (aerobic)

• Treatment concentrates more on removal of smell & color

• Planted gravel filter consist of plants (reeds) & filter materials (graded gravels, river pebbles)

• Filter is permanently soaked (up to 50 cm from bottom) in water

• Flow direction is horizontal

• Suitable for pre-treated wastewater

internal water level

inflow manhole

upper sand layer central outlet shaft

final outlet

cross distribution trench filled with rocks

main filter body filled with coars gravel cross collection

trench filled with rocks

perforated pipe connected to

swivel pipe for adjustable height

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Technical overview

Flow principle of horizontal filter

Inlet

Slope protection with gravel

Outlet Pre- treatment

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