Evaluation of changes in activated sludge and sewage sludge quality by FTIR analysis and laser diffraction

Preliminary analysis: Effect of a rotary generator of hydrodynamic cavitation on rheology and methane yield of wastewater sludge

“…Additionally, significant differences were observed in the band regions associated with amino acids that constitute the microbial cell walls, specifically with peaks at 1648 and 1537 cm −1 [59] . Furthermore, distinctions were observed in the band characteristic of bacterial cell walls for both Gram-positive and Gram-negative bacteria with its peak at 1234 cm −1 [60] . Further analytical details can be found in the Supplementary material 5 .…”

Electrochemical Phosphorus Recovery from Anaerobically Digested Sludge: Improving Product Purity and Concentration

“…The FTIR peak at wavelength 1650 cm –1 suggested the presence of amide in the ADS filtrate product, which was not found in the EPRS product (Figure S9). The EPRS process significantly reduced Zn, Al, and Mn levels by more than 90% compared to the direct precipitation in the ADS filtrate (Figure S10). The EPRS product had heavy metal contents at 6.49 mg kg –1 for Ni, 0.02 mg kg –1 for Cd, 16.93 mg kg –1 for Cr, 1.19 mg kg –1 for Pb, and 1.71 mg kg –1 for Cu, which represented 78–99% of reduction compared to those in the ADS filtrate product (Figure B) and 2 orders of magnitude lower than those in a solid product via cathodic precipitation reported previously .…”