How to create an energy efficient WWTP together?
According to the Electric Power Research Institute, much has changed in the water and wastewater industries in recent years: evolving environmental requirements, rising operating costs, technological breakthroughs, and improved load management opportunities.
Also, according to EPRI, energy efficiency is a top priority in the wastewater treatment business, along with methods to recover energy from the wastewater stream. Between 1998 and 2008, the number of institutions implementing techniques larger than the secondary treatment climbed all over globe. And as processing needs became more severe, the energy required increased.
What is aeration?
Aeration is commonly used in advanced wastewater treatment to remove dissolved organic matter and nutrients. According to EPRI, aeration is the most energy-intensive process in wastewater treatment, accounting for half of total wastewater treatment costs, followed by bio-solids processing and pumping.
Bio-solids handling and treatment can account for one-third of total energy consumption in wastewater treatment plants. If energy recovery cannot be achieved, the goal will be to render the bio-solids harmless so that they can be discarded. Costs could be significant if it is dewatered, which would necessitate the use of natural gas. Energy costs are low when bio-solids are dried in beds. If the bio-solids are incinerated, the costs could rise again.
Water Sector: An energy intensive industry
The water sector is one of the most energy-intensive industries, accounting for about 2% of total global electricity usage for wastewater aeration. As a result, it is in the best interests of the environment and the economics of wastewater treatment plants for operators to uncover energy-saving opportunities.
1. Performance of Existing Processes
Identify operational demands, maintenance, and defective equipment by conducting an on-site study to assess energy use and efficiency. Use data on energy consumption to better understand usage trends and determine where energy savings might be accomplished. Operational modifications should be made to implement audit recommendations.
2. Operational modifications
Process equipment should be evaluated on a regular basis for its condition, performance, and remaining useful life. Older equipment is less efficient, more expensive to repair, and typically consumes more energy than newer models. Given that the aeration step in a wastewater treatment plant consumes the most energy, this should be a starting point for efficiency improvements.
Netsol Water, a complete secondary treatment solution, would cut energy costs by at least four times and sludge production by half.
3. Using wastewater to generate renewable energy
Anaerobic digesters can help to boost energy efficiency by converting wastewater into renewable energy. An anaerobic digester produces methane that can be later employed in a system to give energy to the facility at much lower costs. The overall decrease on energy expenditures can enable the facility to become more self-sufficient.
4. Educating the Staff
Educating treatment system operators on the relationship between energy efficiency and facility operations is critical to meeting energy targets and discovering new efficiency opportunities. By involving operators in the process and soliciting feedback, efficiency measures are suggested and implemented. After all, it is the staff who deals with the processes on a daily basis throughout the facility, and this is invaluable insight.