Impact of silver nanoparticles on wastewater treatment in the SBR

Abstract

The commonly application of nanoparticles (NPs) in commercial and industrial products inevitably increases their release into the natural environment which poses a threat to human health and ecosystems. A recent study of nanoparticles in wastewater treatment showed that most NPs are retained in the equipment used for biological wastewater treatment. The aim of the study was to determine the effects of silver nanoparticles (Ag NPs) on wastewater treatment in the SBR bioreactor. The effluent from the SBRs was analyzed for total organic carbon (TOC), suspended solids (SS), pH and total silver. Microbial observations of activated sludge were made and, on this basis, the Madonia biotic index was specified. After nanoparticles were added, the composition of microorganism communities of the activated sludge changed, and the largest community was the one of creeping ciliates. The efficiency of the effluent treatment measured by the concentration of TOC removal showed that Ag NPs were found to have remarkable effects on TOC removal in the SBR. The obtained results showed that purified wastewater included a low concentration of Ag nanoparticles. The main removal pathway of Ag NPs was via sorption as well as possible aggregation and sedimentation onto the sludge.

Influence of Polyvinylpyrrolidone Concentration on Properties and Anti-Bacterial Activity of Green Synthesized Silver Nanoparticles

“…Noble metal nanoparticles, mainly silver nanoparticles (AgNPs) have been an attractive research subject due to their exceptional properties [ 1 ], such as biocompatibility, high surface area, quantum confinement, variable size, shape and structure (nanosphericals, nanorods, nanocubes and nanotriangles). AgNPs are extensively incorporated in various fields [ 2 ] such as in cosmetics [ 3 ], food packaging [ 4 ], bioengineering, biomedicine [ 5 , 6 , 7 , 8 , 9 , 10 , 11 ] (biosensing, anticancer, antimicrobial, antileishmanial, antioxidant, medical treatment, drug delivery and cell imaging), catalysis [ 12 ], antimicrobial paints [ 13 ], surface cleaners, air and water disinfection [ 14 ] and wastewater treatment [ 15 ]. Various methods were successfully reported for the synthesis of silver nanoparticles including chemical and physical routes [ 16 ].…”

Advances in the Applications of Nanomaterials for Wastewater Treatment

“…Silver nanoparticles have been shown to be effective against drug-resistant bacteria and biofilm-forming bacteria, as they prevent the biofilm from forming [106]. Madeła [107] examined the influence of 2 mg/L AgNPs on the biological wastewater treatment process in an SBR reactor. The AgNPs showed enhancing effects on the efficiency of the treatment process, as determined by the TOC removal (Figure 6).…”

Removal of Contaminant in Electroplating Waste Water and Its Toxic Effect Using Biosynthesized Silver Nanoparticles

“…During the wastewater treatment with Ag NPs, the pH increased from 0.83 to 5.98. The pH changes observed in the treated wastewater may be due to their exposure to Ag NPs (Madela, 2018). Variations of pH can stimulate aggregation of particles by altering their surface charge properties and under acidic conditions, accumulation and sedimentation do not occur (Li et al, 2013).…”