The use of sludge as a micronutrient for the improvement of biogas production from seaweed: the integration of two sources of environmental concern to bring new opportunities

Large quantities of seaweed in marine environments and coastal areas can cause serious hygienic environmental problems. Anaerobic digestion (AD) could provide a solution also be useful for the production bioenergy fertilizer. However, AD algae biomass has some limitations further work is required on process. To increase efficiency process, batches 350 mL feedstock containing (Sargassum sp.), inoculum, different dosages sludge from drinking water treatment (DWTS) as micronutrient source to improve biogas were digested 500 glass reactor under mesophilic conditions, leading significantly enhanced methane production. The highest yield (199 NmL g−1 VS) was observed when 6 mg L−1 DWTS added, which showed 30% improvement compared with control digester accounted 249.4 kWh net energy per ton. biodegradability index increased by 10% after addition DWTS. © 2021 Society Chemical Industry John Wiley & Sons, Ltd