Question

Waste water treatment is a crucial process to ensure that the waste water can be safely recycled back to the environment. However, there are certain challenges or issues related to this waste water treatment that can endanger the environment. In your opinion (supported by journal or academic references), what are those challenges and how can civil engineers prevent those happening>

Answer 1

1.Energy consumption is one of the largest expenses in operating a wastewater treatment plant. Wastewater treatment is estimated to consume 2 - 3% of a developed nation’s electrical power, or approximately 60 tWh (terawatt hours) per year. In municipal wastewater treatment, the largest proportion of energy is used in biological treatment, generally in the range of 50 - 60% of plant usage.

The solution for this is Changes in biological treatment processes have the potential to significantly reduce the energy demand at a treatment plant. Some examples of solutions include; use of fine screens in primary treatment; membrane technology for the aeration process; and direct treatment of high concentration return streams.

2. Sludge is the residue generated during physical, chemical and biological treatment. A major environmental challenge for wastewater treatment is the disposal of excess sludge produced during the process

The solution for this is Safe and long term solutions for the destination of sludge produced by wastewater treatment plants are a vital element of a sustainable functioning facility. The recycling of sludge, containing useful organic matter and nutrients in agriculture is considered as the best solution. Some more modern treatment technologies are even able to reduce the burden of sludge by lowering its production