Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.

Shiv Nadar University

River sand is used as fine aggregate in concrete and cement mortar. The rapid expansion in construction activity witnessed in the country over the last decade has led to an incessant demand for river sand. Hence river sand is being excessively mined at the riverbeds and is leading to fast depletion of the precious natural resource. This presses the need for exploration of alternative materials which can be adopted as fine aggregate by construction industry to build concrete and masonry buildings. One possible candidate is coal bottom ash. Coal-based thermal power plants produce tonnes of coal bottom ash along with fly ash during power generation. Coal bottom ash is coarse particles settled at the bottom of cooling towers. The coarse nature of coal bottom ash particles can be harnessed and explored. The present study focuses on utilization of coal bottom ash as fine aggregate in cement mortars. River sand is fully and partially replaced by coal bottom ash. Five different proportions of river sand being replaced with coal bottom ash are adopted, namely 0, 25, 50, 75 and 100%. Performance of replacement of river sand with coal bottom ash is assessed in terms of particle size distribution (PSD) curves, workability and mechanical properties. Sieve analysis and mortar flow table test are conducted to assess the PSD curves and workability. Compression tests are conducted on cement mortar cubes (with different proportion of coal bottom ash) to determine compressive strength. Further, compression test is conducted on cement mortar cylinders in a displacement-controlled universal testing machine (UTM) to obtain the stress–strain curve and modulus of elasticity. The study found that river sand replaced with up to 50% coal bottom ash exhibited satisfactory performance as fine aggregate in cement mortar.

Civil Engineering

(SoE) School of Engineering

Sustainable Cities and Resilience

Replacement of River Sand with Coal Bottom Ash as Fine Aggregate in Cement Mortar

The treatment of domestic sewage using a moving bed hybrid <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/bioreactor">bioreactor</a> (MBHBR) was investigated by varying the concentrations of <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/chemical-oxygen-demand">chemical oxygen demand</a> (COD) (156&nbsp;±&nbsp;14-1141&nbsp;±&nbsp;78 mg/L), ammonia (NH3-N) (2&nbsp;±&nbsp;0.08-48.24&nbsp;±&nbsp;0.93 mg/L), phosphorus (PO4-P) (97&nbsp;±&nbsp;3.2-281&nbsp;±&nbsp;2.65 mg/L), and hydraulic retention times (HRTs). Initially, the reactor was operated at start-up mode (COD: 156&nbsp;±&nbsp;14 mg/L), and gradually the COD concentrations were increased from phase-I (257&nbsp;±&nbsp;24 mg/L) to phase-V (1141&nbsp;±&nbsp;78 mg/L) by reducing the HRTs from 48 to 3 h. A significant improvement in COD removal, maximum up to 96%, was observed at a concentration of 858&nbsp;±&nbsp;51 mg/L (phase-IV), then a sudden drop up to 81% was observed at a higher concentration of 1141&nbsp;±&nbsp;78 mg/L (phase-V). Due to the increase in COD concentrations, average NH3-N removal was dropped from 85 to 32% from phase-I to Phase-V, respectively. In addition, the stability of MBHBR was studied to understand its performance in shut-down and shock loading phases. The co-treatment of sewage and leachate was also performed in MBHBR (COD: 864-881 mg/L and HRT: 6 h), which showed a COD removal of 77%–80% and NH3-N removal of 60%–94%. Proteobacteria was identified as a predominant species in MBHBR, which played a significant role in the co-treatment of sewage and leachate. The maximum biodegradation rate (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub is="true"><mrow is="true"><mi is="true">r</mi></mrow><mrow is="true"><mi mathvariant="normal" is="true">max</mi></mrow></msub></math>) and half-saturation constant (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub is="true"><mrow is="true"><mi is="true">K</mi></mrow><mrow is="true"><mi mathvariant="normal" is="true">s</mi></mrow></msub></math>) were estimated as 13.3 mg/L h and 361.8 mg/L, respectively.

Fulltext

Environmental Technology & Innovation

<a href="https://www.sciencedirect.com/science/article/pii/S2352186421006465">Treatment of domestic sewage and leachate using a moving bed hybrid bioreactor</a>

Worldwide, solid waste disposal is a serious problem rising day by day with the increase in population. Open dumping and incineration is a common practice for municipal solid waste disposal in India and other developing countries. This practice raises the acute pollution problem as well as a health risk. There is an urgent need for sustainable techniques to address this problem to generate a minimal impact on the environment. There are many sustainable methods for solid waste management, viz., sanitary landfilling, composting, vermicomposting, anaerobic digestions, and ethanol production. Among all the microbes and biological agents are playing a very important role. This chapter presents a detailed review of solid waste management and sustainable solution to this problem with the help of microbes and biological agent.

Environmental and Agricultural Microbiology: Applications for Sustainability

<a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119525899.ch18">Role of Microbes and Microbial Consortium in Solid Waste Management</a>

Aeration or oxidation is one of the crucial steps during the plant-derived natural indigo dye production process. However, the lack of scientific information to determine adequate aeration conditions during natural indigo dye production is one of the significant limitations of the process. Therefore, the present study focuses on selecting suitable parameters to assess the optimum oxidation for indigo dye formation. Initially, the effect of direct oxidation parameters, such as dissolved oxygen (DO), oxidation-reduction potential (ORP), and pH on indigo dye formation, were evaluated. However, insignificant ( p &gt; 0.05) co-relation was observed between the direct parameters on indigo dye formation. Alternatively, due to the agglomeration and water insolubility properties of indigo dye, particle size measurement was considered for real-time monitoring of indigo dye formation. It was established that the minimum indigo particle agglomeration size of ≥ 100 μm could be considered as a significant parameter to determine the indigo dye formation. It can act as an indirect indicator of adequate oxidation.

Environmental Challenges

Influence of various oxidation parameter(s) for natural indigo dye formation from Indigofera tinctoria L. biomass

Worldwide, solid waste disposal is a serious problem rising day by day with the increase in population. Open dumping and incineration is a common practice for municipal solid waste disposal in India and other developing countries. This practice raises the acute pollution problem as well as a health risk. There is an urgent need for sustainable techniques to address this problem to generate a minimal impact on the environment. There are many sustainable methods for solid waste management, viz., sanitary landfilling, composting, vermicomposting, anaerobic digestions, and ethanol production. Among all the microbes and biological agents are playing a very important role. This chapter presents a detailed review of solid waste management and sustainable solution to this problem with the help of microbes and biological agent. © 2021 Scrivener Publishing LLC.

World University root node

Environmental and Agricultural Microbiology: Advances and Applications

Role of microbes and microbial consortium in solid waste management

Abstract: The emerging demand of natural indigo dye due to the environmental and sociological concerns imparted by the synthetic dye helps in leveraging the conventional natural indigo dye production process in many developing countries, including India. Despite having remarkable global market potential, the high price of natural indigo dye impedes its extensive commercialization. Therefore, in the present study, the economics of natural indigo dye is evaluated through life cycle cost (LCC) analysis by considering the traditional indigo dye production process in India using the plant biomass Indigofera tinctoria L. The life cycle model includes cultivation of Indigofera biomass, as well as the production and processing of indigo dye and the cost involved in each step. Along with the detailed cost analysis, the present study also includes socio-economic analysis and possibilities of cost reduction based on the outcome of sensitivity analysis. From the LCC analysis, the life cycle cost of Indigofera biomass cultivation is $420.74 ha−1 year−1, whereas the indigo dye production cost is $113 ton−1 of Indigofera biomass. For an annual dye production of 1000 tons, the present study estimated the economic stabilization of rural farmers and labours by an annual employment generation of 196,250 man-days year−1 and 12,50,000 man-days year−1, respectively. By sensitivity analysis, the raw material price was identified as the major contributor in the total indigo dye production cost. As a cost reduction measure, the combination of biomass yield (70 tons) and reduction in the biomass production cost (50\%) was found to be suitable. Utilization of by-product generated from the dye industry into value-added products could contribute towards a cost reduction of 22\% in the Indigofera biomass cultivation and a cost saving of $37.4 ton−1 of biomass in the indigo dye production cost. Graphic Abstract: [Figure not available: see fulltext.]. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.

Clean Technologies and Environmental Policy

Life cycle cost analysis of natural indigo dye production from Indigofera tinctoria L. plant biomass: a case study of India

In present study, statistical optimization of biodiesel–derived crude glycerol fermentation to DHA by immobilized G. oxydans cells over polyurethane foam is reported. Effect of DHA (product) inhibition on crude glycerol fermentation was analyzed using conventional biokinetic models and new model that accounts for both substrate and product inhibition. Optimum values of fermentation parameters were: pH = 4.7, temperature = 31 °C, initial substrate concentration = 20 g/L. At optimum conditions, DHA yield was 89% (17.83 g/L). Effect of product inhibition on fermentation was trivial for DHA concentrations ≤30 g/L. At higher concentrations (≥50 g/L), kinetics and yield of fermentation showed marked reduction with sharp drop in Vmax and KS values. Inhibition effect was more pronounced for immobilized cells due to restricted transport of fermentation mixture across polyurethane foam. Retention of fermentation mixture in immobilized matrix resulted in higher localized DHA concentration that possibly enhanced inhibition effect. © 2017 Elsevier Ltd

Bioresource Technology

Process optimization and analysis of product inhibition kinetics of crude glycerol fermentation for 1,3-Dihydroxyacetone production

Rotating biological filter (RBF), which provides higher oxygen mass transfer has been developed for treating gaseous volatile organic compounds (VOCs) such as BTEX (Benzene, toluene, ethylbenzene and xylene) at higher concentrations. The screening of enriched cultures has been done initially to enhance the performance of RBF for treating xylene, toluene and xylene, and BTEX at various loading rates. The removal efficiency of BTEX was maximum (82%), higher than toluene and xylene (79%), and xylene (72%). The presence of xylene enhanced the removal of toluene in the mixture. In the BTEX, toluene was found to be highly biodegradable followed by ethylbenzene, benzene and xylene. The RBF also removed nutrients from wastewater along with VOCs. The stability study of RBF showed that supply of nutrient media influenced the RBF performance more. Further, the predominant strain identified in the mixed culture was Enterobacter cloacae SP4001, responsible for biodegradation of BTEX. © 2017 Elsevier Ltd

Treatment of gaseous volatile organic compounds using a rotating biological filter

Benzene is one of hazardous pollutants generated from paint, chemical, and petrochemical industries have a harmful impact on human health and the atmosphere. This study reports benzene biodegradation by indigenous mixed microbial culture in shake flasks over a concentration ranging from 25 to 600 mg/l, and the kinetics involved in the process has been modeled. Experimental data obtained were fitted to both inhibition and noninhibition models to determine the biokinetic constants. Haldane model was best to predict the experimental data. The central composite design was further used for optimization of pH and benzene concentration to enhance the benzene biodegradation. At an optimum pH of 7.05 and benzene concentration of 332.82 mg/l, the maximum estimated specific growth rate and degradation rate were 0.05 1/h and 6.01 mg/l h, respectively. The LC-MS analysis of sample indicate the presence of catechol, cis-1,2-dihydrobenzene-1,2-diol, and 2-hydroxymuconate semialdehyde as intermediates, which justifies the developed pathway of benzene biodegradation. The predominant microorganism in the mixed culture responsible for benzene degradation was later identified to be Enterobacter cloacae SG208. The results provide insight into the process of benzene biodegradation and prove the potential of indigenous mixed culture for treatment of benzene. © 2016 Elsevier Ltd

International Biodeterioration and Biodegradation

Benzene biodegradation by indigenous mixed microbial culture: Kinetic modeling and process optimization

Rotating biological contactors (RBCs) are low-cost, efficient and an eco-friendly volatile organics control technique. In this study, a state-of-art disk-based RBC has been modified to a drum-based with sponge supporting medium and its performance at different inlet loading rates (ILR) of gaseous benzene, and its effect on elimination capacity (EC) and removal efficiency (RE) have been investigated. The results showed that the RE remained over 90% up to the ILR of about 8 g m-3 h-1, and decreased to about 80% with the further increase in ILR. The EC reached maximum to about 45 g m-3 h-1 at a benzene load of about 69 g m-3 h-1. The EC of benzene increased with the increase in loading rate, but the RE showed an opposite trend. The production of carbon dioxide, which determines the degree of pollutant degradability, also increased with the increase in EC. Along with benzene the nutrients (NH3-N and PO4-P) from liquid phase also got removed in RBC, which shows its potential application in industries. Furthermore, a potential benzene degrader was tentatively identified as genera Enterobacter. The maximum biodegradation rate (rmax) and half saturation constant (Ks) were determined as 21.46 g m-3 h-1 and 1.71 g m-3, respectively. © 2016 Elsevier Ltd.

Benzene control from waste gas streams with a sponge-medium based rotating biological contactor

Volatile organic compounds (VOCs) prevalent in our atmosphere are of major environmental concerns. Several methods of controlling VOCs exist. Most of them have direct or indirect environmental consequences in terms of materials they use and wastes they produce albeit control VOCs. It has been found that conventional techniques especially of physical and chemical nature pose a number of problems such as high on cost, high material requirement, produce lots of waste and contribute to climate change and environmental degradation. Various biological oxidation methods adopted in various reactors for controlling gaseous VOCs have been reviewed, pros and cons of these technologies have been studied and the sensitive parameters for improving removal efficiency along with their environmental implications have been identified. It has been found that rotating biological contactor (RBC) could be an effective alternative to control gaseous VOCs because of its simple design and operation. Further, it provides higher oxygen transfer, offers better mixing, consumes low energy and has potential of higher removal efficiency as compared to the other biological techniques. There is, moreover, an ample scope in improving its gaseous-control efficiency by optimizing the parameters like rotational speed, hydraulic loading rate, and hydraulic retention time and similarly by the use of different media, biofilm characteristics and dissolved-oxygen levels. With these scopes, RBC can be an eco-friendly, and promising option for controlling gaseous VOCs. © 2014 Elsevier Ltd. All rights reserved.

Journal of Environmental Chemical Engineering

Biological oxidation of gaseous VOCs - Rotating biological contactor a promising and eco-friendly technique

Agro-industrial waste is one of the most abundant, renewable, and low-cost biomass, which is mainly composed of lignocellulose. In addition to this, these biomasses are a rich source of bioactive compounds and are widely used for the production of high-value products. Further utilization of these biomasses reduces environmental contamination, ecological damage, and other hazards associated with it. Compared to chemical treatment methods, which require harsh operating conditions and toxic chemicals, biological treatment is a promising technology with low-cost and environmentally friendly processes. These agro-industrial wastes are mainly produced from different industries, either in the form of solid or liquid. In this context, the present chapter has highlighted the utilization of various agro-industrial wastes for the production of various value-added products like biogas, biofuel, compost, biomolecules, and biomaterials. The use of agro-industrial wastes as raw materials can make the agro-industries more sustainable.

Urban Mining for Waste Management and Resource Recovery

Valorization of Solid and Liquid Wastes Generated from Agro-Industries

In this study, aerobic granular reactor (AGR) was used to treat landfill leachate by changing the concentrations of <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/chemical-oxygen-demand">chemical oxygen demand</a> (COD) (668&nbsp;±&nbsp;110-1149&nbsp;±&nbsp;93 mg/L), ammonia (NH3–N) (30&nbsp;±&nbsp;3.3-48&nbsp;±&nbsp;1.3 mg/L), and phosphorus (PO4–P) (147&nbsp;±&nbsp;18-221&nbsp;±&nbsp;17 mg/L). The average COD removal was gradually reduced from 81 to 75%, increasing COD concentrations from 668&nbsp;±&nbsp;110 to 1149&nbsp;±&nbsp;93 mg/L. In phase I, the maximum removal of COD (94%) and NH3–N (85%) were observed at influent concentrations of 668&nbsp;±&nbsp;110 mg/L and 30&nbsp;±&nbsp;3.3 mg/L, respectively. Significant removal of PO4–P was observed, resulting in a maximum of up to 87%, further reducing up to 34% due to an increase in influent PO4–P concentration. The SVI30 reduced from 77 mL/g to 24.15 mL/g towards the end of phase III indicates the formation of granular biomass. The stability of AGR was also investigated in extreme conditions like shut-down and shock-loading phases. The treatment of real leachate diluted with wastewater (<math xmlns="http://www.w3.org/1998/Math/MathML"><mo is="true">∼</mo></math>20:80% v/v) in AGR showed a significant COD, NH3–N, and PO4–P removal of 62%–65%, 61%–93%, and 56%–64%, respectively. Mass balance analysis indicated that the AGR requires a lower nitrogen percentage for microbial assimilation than the COD and phosphorus. Proteobacteria and Planctomycetes were identified as the predominant (80%) bacterial community in aerobic granules responsible for removing COD, NH3–N, and PO4–P from leachate using AGR. The maximum biodegradation rate (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub is="true"><mrow is="true"><mi is="true">r</mi></mrow><mrow is="true"><mi mathvariant="normal" is="true">max</mi></mrow></msub></math>) and half-saturation constant (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub is="true"><mrow is="true"><mi is="true">K</mi></mrow><mrow is="true"><mi mathvariant="normal" is="true">s</mi></mrow></msub></math>) of COD in AGR were determined as 123.5 mg/L h and 309 mg/L, respectively.

<a href="https://www.sciencedirect.com/science/article/pii/S2352186422002024">Simultaneous removal of carbon, nitrogen, and phosphorus from landfill leachate using an aerobic granular reactor</a>

Landfill leachate comprises highly toxic and hazardous compounds posing adverse health effects to the ecosystem and human populations. These leachates must be subjected to suitable treatment before discharging to the environment. However, the higher operational cost and presence of recalcitrant matter in the leachate make the conventional physico-chemical processes incompetent for treatment. Recent advancements in biological processes over physico-chemical processes result in the development of aerobic granular reactor (AGR) for treating landfill leachate. Small footprint, less energy demand, high <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/microbial-activity">microbial activity</a>, long-term operational stability with better removal of organic pollutants, and resistance to high <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/shock-loads">shock load</a> make AGR a promising technique for treating leachate. Longer granulation time and instability of aerobic granules are some of the major shortcomings that limit its commercial application. Additionally, the single-stage treatment of landfill leachate using AGR poses several difficulties, such as low organic and recalcitrant <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/pollutant-removal">pollutant removal</a> efficiency, which needs post-treatment. Hence, an integrative approach is imperative for treating landfill leachate with a high organic load to meet the effluent standard. The present study highlights an in-depth critical review of various biological processes, recent developments in AGR, and the factors affecting its performance, mass balance, and the kinetics involved during landfill leachate treatment. Subsequently, the integrated process for the treatment of landfill leachate has been summarized along with the future prospects of AGR.

Environmental Nanotechnology, Monitoring & Management

<a href="https://www.sciencedirect.com/science/article/pii/S2215153222000496">Recent developments in landfill leachate treatment: Aerobic granular reactor and its future prospects</a>