Wastewater byproduct holds profit potential
New technologies to boost energy extraction from sludge, report says.
The potential to harness energy from wastewater sludge will almost double over the next decade, a recent study suggests.
Sludge can represent 20% and 50% of wastewater treatment cost, as plants need to dispose vast quantities of the byproduct on a regular basis. As a result, utility companies have started to look at ways to extract value from the waste material, developing technologies that already hold the potential to recover value to the tune of US$25bn, according to Lux Research, who conducted the study.
Lux Research estimates that the development of those technologies will increase the market opportunity for resource recovery to US$45bn by 2020.
Technologies focused on recovering energy from sludge show the most promising value proposition, according to the report, and are expected to capture 64% of the overall market in 2020.
The report finds that improving production of biogas are most likely to recoup costs. Several technologies – including ultrasonic cavitation, mechanical disintegration and thermal hydrolysis – aim to improve on anaerobic digestion, a well-established method for extracting biogas from sludge.
Deriving alternative fuels, such as syngas and biodiesel, from sludge is also viable. These approaches offer benefits such as relatively low capital costs, and high solids removal, but have the drawback of being equipment-intensive.
Nutrient and material recovery technologies are as yet too complex and energy-intensive to produce value added, according to Lux Resarch. The exception is crystallization technology, which uses a minimum of chemicals and a simple process design to recover up to 85% of phosphorus from wastewater.
“Sludge production volumes will continue to grow with increasing population and country wealth,” concludes Heather Landis, an analyst for Lux Research and the report’s lead author. “By turning sludge from a costly material to treat into a profitable revenue stream, recovery technologies make fertile hunting grounds for executives and investors looking for opportunities in the hydrocosm.”