High rate of biological removal of sulfate, organic matter, and metals in UASB reactor to treat synthetic acid mine drainage and cheese whey wastewater as carbon source

Abstract

The anaerobic biological treatment of sulfate‐rich effluents, such as acid mine drainage (AMD), is mediated by sulfate‐reducing bacteria (SRB). This process involves the reduction of sulfates in the presence of an electron donor. Complex carbon compounds can be used as electron donors. In the present study, was used an upflow anaerobic sludge blanket (UASB) reactor to co‐treat a low‐pH synthetic AMD and cheese whey wastewater (CWW). Were observed higher sulfate and COD removal rates (1,114 ± 88 and 1,214 ± 128 mg L−1 day−1, respectively) at higher sulfate and applied COD loading rates (1,500 mg L−1 day−1). The overall pH of the effluent remained above 6.4 without any bicarbonate supplementation. Almost 100% of the Fe, Zn, and Cu was removed and the presence of metals improved the process. The use of a single reactor to treat AMD and CWW is promising. Practitioner points Wastewater cheese whey was electron donor for treating acid mine drainage in an UASB reactor. Metals additions in the system indicated an increased removal of COD. About 99% of the metals were removed with the treatment.

A review on upflow anaerobic sludge blanket reactor: Factors affecting performance, modification of configuration and its derivatives

“…If toxic substances were present, it would be adsorbed onto granules. If toxic substances are present in wastewater in moderate range, as a self‐defense mechanism, EPS is secreted by biomass to strengthen the granules (Mungray et al, 2016; Sampaio et al, 2019). The operating conditions played a major role in the achievement of better substrate removal, and it is evident that the operating conditions chosen to carry out experiments depend on the type and characteristics of the substrate.…”

“…Unlike typical UASB reactor, co‐digestion requires longer HRT to digest the additional substrate. Substrate with high carbon content is generally preferred to maintain large energy recovery potential and to reduce the competition between the SRB and MPA for the treatment of sulfate‐containing wastewater (Sampaio et al, 2019). The increase in COD/SO 4 2− ratio due to addition of carbon source favors methanogenesis by suppressing the SRB (Mainardis et al, 2020).…”

Up-Flow Anaerobic Sludge Blanket (UASB) Technology for Energy Recovery: A Review on State-of-the-Art and Recent Technological Advances

“…The addition of metals and natural elements showed to have a positive effect both on COD removal and on biogas production in UASB co-digestion of high-loaded substrates [ 76 , 77 ]. Carbon-rich co-substrates can be strongly beneficial, instead, when working with sulfate rich-wastewater, given the competition between sulfate-reducing bacteria (SRB) and methanogenic biomass [ 80 ], which is reduced by C addition. On the other hand, nutrient and alkalinity can be provided by animal residues when working with highly degradable and acidifying substrates [ 81 ].…”

Mine drainage: Remediation technology and resource recovery

“…An upflow anaerobic sludge blanket (UASB) reactor was used to simultaneously treat AMD and cheese whey wastewater where cheesy whey also served as electron donor (Sampaio, dos Santos, da Costa, Rodriguez, & Sancinetti, 2020). A rapid removal rate of metals, sulfate, and organic matter was observed.…”