Wastewater treatment by effective and economical methods is an area of investigations in environmental research. Biotechnological methods are used in the treatment technologies commonly in the form of activated sludge and trickling filters. Nanomaterials for sorptive removal of pollutants have advantages like high surface area, selectivity, and percentage removal. Silver and iron nanoparticles are used for treatment of effluent for contaminant removal. Termed as green synthesis, these biotechnology-based synthesis methods are environment friendly and sustainable. Various treatment technics such as membrane bioreactors, photocatalysis, adsorption, etc., can be made more effective and customized for specific pollutant using nanotechnology approach. The combination of these two methods termed as nanobiotechnology and bionanotechnology, based on transfer of direction advantages, has potential to address the issue of many biological and nonbiological contaminants in wastewater which cannot be effectively removed by other advanced methods.
TopIntroduction
Conventional wastewater treatment contains physical, chemical and biological treatments. The biological molecules incorporated in nanoparticles have distinct advantages in term of specificity of binding which can be utilized for capturing chemicals from environment. Presence of microbial community in pharmaceutical and healthcare discharge wastewater poses the challenges like change in antibiotic resistance and difficulty in its removal from wastewater. Nano-materials like silver nanoparticles are good antimicrobial agents. Advantages of nanofiltration can be coupled in membrane bioreactor to utilize advantages of biotechnology and nanotechnology for such cases (Al-Gheethi et al., 2020; Lu, et al., 2016; Malik et al., 2022; Rai et al., 2022). Thus, integration nanotechnology with various biological treatments namely microbial fuel cell, aerobic digestion, membrane bioreactor and biosorption can overcome the limitations and offer acceptable solution for wastewater treatment (Al-Gheethi et al., 2020; Lu, et al., 2016; Malik et al., 2022; Rai et al., 2022). This book chapter aims to shed light on applications of combination biotechnology and nanotechnology for wastewater treatment. The green, biotechnology-based modification and synthesis of nanomaterial and nanoparticles that can be used for wastewater treatment is discussed in the chapter. Also, it contains review of literature on the application of nanomaterial for wastewater treatment containing various pollutants namely heavy metals, pathogens, pesticides and dyes.
Brief Description of Industrial Wastewater Treatment Problem
The treatment of industrial wastewater is one of the major focus areas in modern industrialization. With increased awareness and stringent norms, research in wastewater treatment processes is promoted by government as private sector. The reuse, recycle and reduce (Three R) philosophy has become popular. The effluent which used to be treated to meet the regulatory norm and disposed off in the reservoir needs to be treated further to render usefulness, either in domestic, agricultural purposes. Some investigations are also focused on making it potable. Disinfection becomes crucial in such cases. The effluent needs to be treated with advanced treatment techniques to make it useful for various applications. In addition to conventional treatments, the need of specific advanced treatment methods is highlight of modern effluent treatment processes. Various advanced treatments include, advanced oxidation methods, cavitations, membrane bioreactors, adsorption on carbon nanotubes and ion exchange.
Concept of Nanotechnology and Its Advantages
Nanoparticles are being explored for adsorption of specific pollutant from wastewater. Nanoparticles are unique in terms of their properties. Nano-biotechnology aims to utilize advantages of nanotechnology to biotechnology and exploit nanotechnology-based systems and biomemitic technologies to synthesize nanostructures. Biological wastewater treatments are inherent part of conventional treatment methods for wastewater. Nanoparticles are finding application in modern wastewater treatment methods due to greater surface area, specificity, excellent catalyst and adsorption properties. Carbon nanotubes, titanium oxide, magnesium oxide are some common nano-adsorbents used in wastewater treatment.