Providing clean and sufficient drinking water to the population implies that a country is implementing proper water management programmes. Water quality gets degraded due to increased untreated sewage, industrial discharge, and agricultural runoff while also contaminating water reservoirs.
Most of this untreated water merges with water and is consumed by people making them open to diseases like polio, cholera, typhoid, and dysentery. Water treatment is critical and will remain so when meeting rising water demand, depending on how efficiently a country can treat water.
Contributing to the ongoing problem, a research group has demonstrated a process through which wastewater resource recovery facilities would be empowered to obtain revenue. As per the team, this would be possible by converting sludge into biofuel. Further, the system would also be an outstanding contribution to the Waste Disposal Treatment Market. It would decrease disposal costs, thus providing a method that could enable agencies to treat the water better.
The team made use of HTL (Hydrothermal Liquefaction), a biocrude conversion technology developed by PNNL. It helped them analyze around 15,000 wastewater resource recovery facilities. They discovered various challenges these facilities face, such as emerging regulatory requirements, rising operations costs, and aging infrastructure and equipment. Moreover, their study also considered factors such as revenue, 30-year operating period, operating and capital costs, and avoided disposal linked with drying and landfilling/incinerating sewage sludge.
The researchers discovered that facilities with as little as 5 million gallons of wastewater per day could profit financially from employing HTL. These facilities have the potential to handle 79 percent of total untreated municipal sludge in the United States each year, producing almost 1 billion gallons of biocrude and creating a new revenue stream.
Further, researchers also compared their innovation with another widely popular treatment process that converts anaerobic digestion to biogas. The team in the analysis realized that if untreated sludge is changed into biofuels through HTL, it could reduce biosolids disposal costs in the United States itself by $1.4 billion a year, i.e., 43 percent reduction. In addition, it would also lead to an increase in total energy recovery by 188 percent.
Now, the team is set to undertake the task of exploring the potential synergies that may exist between HTL and anaerobic digestion.