Simulation Tool for the Techno-Economic Assessment of the Integrated Production of Polyhydroxyalkanoates as Value-Added Byproducts of a Wastewater Treatment Plant.

Pozo-Morales, Laura; Rosales Martínez, Antonio; Baquerizo, Enrique; del Valle Agulla, Germán

The polyhydroxyalkanoate (PHA) production process that uses mixed microbial cultures combined with main stream wastewater treatment plants (WWTPs) is a competitive integrated resource recovery process in which non-oxygen electron acceptors can be used to enrich the PHA producer. Trials carried out in operating plants are very scarce, and there are no simulation tools available to analyse the feasibility of integrating the two processes. This research presents a novel analysis tool for a techno-economic assessment of value-added biopolymers. A general model for a conventional WWTP has been designed and eventually validated using the operating data collected in the database of a fully operational plant. In the model, a simulation of a PHA production line based on thickened primary sludge as a substrate has been integrated. The assembly has been treated as a closed-loop system with an accuracy level of 0.1% with a limit of 1000 iterations. Two strategies based on internal (ADF) or external (AN/AD) limitations of some nutrients have been contrasted for the selection of a biomass capable of feast–famine PHA synthesis. The ADF strategy was found to be the most favourable system, with a production of 0.226 kg of CODPHA·kg−1 COD. The calculated production cost was EUR 0.11·kg−1 CODPHA. The sludge production was reduced by 6%.

SEWAGE disposal plants; WASTE recycling; MICROBIAL cultures; ELECTROPHILES; CLOSED loop systems

Processes, 2025, Vol 13, Issue 2, p295

2227-9717

Academic Journal

10.3390/pr13020295