Knowledge Agora



Similar Articles

Title Ferric Oxide-Containing Waterworks Sludge Reduces Emissions of Hydrogen Sulfide in Biogas Plants and the Needs for Virgin Chemicals
ID_Doc 14002
Authors Persson, T; Persson, KM; Åström, J
Title Ferric Oxide-Containing Waterworks Sludge Reduces Emissions of Hydrogen Sulfide in Biogas Plants and the Needs for Virgin Chemicals
Year 2021
Published Sustainability, 13, 13
Abstract Ferric oxide-containing waterworks sludge can be used to reduce the formation of hydrogen sulfide during anaerobic digestion. The ferric compound is reduced biochemically in the digester and forms insoluble pyrite in digester sludge. Virgin ferric chloride is often used to solve the hydrogen sulfide problem. Since 2013, Sydvatten AB has supplied a growing number of digestion plants in Sweden with ferric-containing dewatered waterworks sludge derived from the drinking water treatment plant Ringsjoverket to limit the formation of hydrogen sulfide. At the waterworks, ferric chloride is added to enhance the coagulation of organic matter from the source water. The sludge formed in this process is dewatered and landfilled, but also recycled in biogas production in order to decrease the hydrogen sulfide concentration. In this study, the use of sludge for hydrogen sulfide removal in digesters was technically and economically evaluated via case studies from 13 full-scale digesters in Sweden. Compared with the use of fresh ferric chloride, the operational costs are reduced by up to 50% by using sludge. The quality of the sludge is high and its content in metals is low or very low, especially when compared with the requirements of different certification standards for biosolid reuse applied in Sweden. The addition of waterworks sludge containing iron to a digester for the removal of dissolved hydrogen sulfide is a technically and economically good alternative when producing biogas. It is also one step closer to a circular economy, as replacing the use of virgin chemicals with the by-product waterworks sludge saves energy and materials and reduces the carbon footprint of the waterworks.
PDF

Similar Articles

ID Score Article
28042 Udaondo, A; Montes, V; Gimeno, O; Rivas, FJ Excess secondary sludge reuse by H2O2 thermal dehydration(2024)
25376 Salehin, S; Rebosura, M; Keller, J; Gernjak, W; Donose, BC; Yuan, ZG; Pikaar, I Recovery of in-sewer dosed iron from digested sludge at downstream treatment plants and its reuse potential(2020)
6204 Salehin, S; Kulandaivelu, JK; Rebosura, M; Van der Kolk, O; Keller, J; Doederer, K; Gernjak, W; Donose, BC; Yuan, ZG; Pikaar, I Effects of aging of ferric-based drinking water sludge on its reactivity for sulfide and phosphate removal(2020)
8430 Kuokkanen, M; Mentausta, O; Kuokkanen, T Eco- and Material-Efficient Utilization Applications of Biotechnologically Modified Fiber Sludge(2018)Bioresources, 13.0, 1
26265 Górka, J; Cimochowicz-Rybicka, M; Poproch, D Sludge Management at the Krakow-Plaszow WWTP-Case Study(2022)Sustainability, 14, 13
Scroll