treatment options for rainwater harvesting systems

Treatment Options for Rainwater Harvesting Systems

For more information go to: www.cleanwaterstore.com

Malaysian Rainwater in Abundance

Rainwater often used for non-potable water applications

Benefits of Rainwater

Provide water for rural areas

Reduce the dependence and demand of public water supply

Reduction of water bills

Additional water supply for fire protection or emergency use

Reduce land erosion and flooding

Reduce salt accumulation in soil which can be harmful to root growth

Rainwater quality affected by atmospheric contamination

Carbon dioxide (CO2) levels - affect pH, creating acidic waterPollution from industry - industrial pollution such as sulfur dioxidePollution from agriculture – pesticides and herbicides

Rainwater quality affected by roof or other catchment surfaces

Maintaining Roof Water Quality

• Regularly inspect and clean gutters, roof catchments and tank screens.

• Remove overhead branches and clear trees near roof.

• Consider installing gutter screens or guards.

• Ensure tank does not become a mosquito breeding site by preventing access and

cleaning screens regularly.

• Examine tank for accumulation of sludge every year and remove by siphon or by

empting the tank.

• Shock sanitize by adding 40 mm of liquid bleach or 7 grams of granular calcium

hypo-chlorite per 1000 liters of water.

Basic Rainwater System with manual roof-washer

Basic Roof Washers

Commercial Roof Washer Valves

• The roof washer is sized to collect at least 30 liters of water for every 100 sq m of catchment area.

Commercially Available Roof Washer

Large capacity rainwater storage tanks

Polyethylene Tanks

Polyethylene tanks are light

Underground Tanks

Ferro Cement Tank

Water Quality of Rain Water

Rainwater Quality Malaysia

Typical rainwater LSI

Corrosive water can cause heavy-metals such as lead to leach into water from: • Fixtures• Appliances • Water heaters• Brass fixtures• Brass valves

Copper corrosion from rainwater

Langelier Index

• pH• Alkalinity• Calcium carbonate • Total dissolved solids• Temperature

Calcite – Calcium Carbonate

Calcite pH Neutralizers/Filter Systems

www.cleanwaterstore.com/acid-neutralizer.html

Neutralizer with UV Sterilizer

UV Sterilizers

www.cleanwaterstore.com/ultraviolet-sterilizers

Chlorination

Liquid bleach chlorine feeder

Solid pellet chlorine feeders

http://www.cleanwaterstore.com/chlorinator.html

Ozone Treatment

http://www.cleanwaterstore.com/ozone-systems.html

Corona Discharge Ozone Generator with Air Dryer

Ozone Bubbler with Compressor

Rainwater Collection Tank with Ozone Bubbler and automatic ORP controller

Ozone Bubbler in Outside Shed

Ozone Bubbler in Shed

Ozone Bubbler With UV and Calcite Carbon Filter System

Ozone Diagram with Contact Tank

Ozone Recirculation System with UV and Calcite-Carbon Filtration System

Automatic Controls

• ORP can be used to control disinfection

Filtration 50 / 5 Micron

Filtration 1 Micron

Ultra-Filtration

www.cleanwaterstore.com/ultra-filtration