5.6 - Application of Green Technology in Industrial Waste Management

Meaning and Sectors of Green Technology

• Green Technology is technology or an application developed to minimise the harmful effects of human activities.
• Malaysia’s National Green Technology Policy, introduced in 2009, promoted wider use across economic sectors and sustainable resource management.

Sector	Application
Energy supply	Renewable solar, hydro, geothermal and wind energy
Transportation	Vehicles using alternative fuels
Buildings	Environmentally friendly materials and energy-saving buildings
Waste and wastewater management	Recycling and landfill-leachate treatment
Agriculture and forestry	Compost and forest conservation
Industry	Energy-efficient equipment and technology

Waste and Wastewater Management

• Green Technology makes waste management more efficient, reduces greenhouse-gas emissions and produces cleaner discharged wastewater, indirectly lowering the carbon footprint.
• Leachate is contaminated liquid formed when water percolates through solid waste.
• Effective solid-waste management requires community participation as well as local-authority action.
• Waste is segregated, collected and sorted. Treatment routes include recycling, composting organic waste, incineration and landfilling; landfill management includes methane-gas recovery and leachate treatment.
• Wastewater is liquid waste containing human waste, food waste, oils or chemicals.
• Wastewater includes domestic wastewater, stormwater runoff and industrial wastewater. Industrial wastewater may contain acrylonitrile, methylbenzene, toluene and heavy metals such as arsenic, mercury and lead.
• These hazardous substances are difficult to biodegrade, so systematic treatment is needed to protect the environment and human health.

Electrocoagulation of Industrial Wastewater

• Electrocoagulation applies electrolysis to landfill leachate and other wastewater.
• Carbon or copper electrodes are placed in wastewater, which acts as the electrolyte. Pollutants form flocs that separate from the water and are removed as sludge.
• Properly treated sludge may be used as agricultural fertiliser or disposed of appropriately according to its composition.
• Treated wastewater may be reused for crop irrigation or discharged as effluent.
• Effluent is liquid waste discharged into a drainage system or water source.

1. Pump in wastewater.
2. Screen out solid waste.
3. Carry out electrocoagulation.
4. Separate solids and wastewater by settling.
5. Collect sludge.
6. Treat the wastewater further.
7. Discharge effluent to a water source.

Importance in Daily Life

• Green Technology reduces pollution, improves resource management and waste treatment, provides cleaner energy, mitigates global warming and raises living standards.
• It also drives innovation, creates new industrial sectors and generates employment while retaining the original purpose of technology.