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Oil spill contamination occurs due to exploration activities in the deep sea and downstream activities such as oil transportation via pipelines, oil-tankers (marine and terrestrial), re-fineries, finished product storage, distribution, and retail distribution setup. Physico-chemical technologies are accessible for oil spill clean-up, but oil bioremediation technologies are proven to be more affordable and environmentally friendly. The aim of this book chapter is to give deeper knowledge about the bioremediation technology of oil spills. This chapter discusses the nature and composition of crude oil, bioremediation agents and strategies, bioremediation on different matrices (water, soil sludge), application strategy, and future prospect of bioremediation technology.

The most problematic issue related to textile wastewater is dyes. The occurrence of toxic and carcinogenic compounds in textile dyes creates aesthetic problems and affects the aquatic ecosystem. Dyestuff removal methods include physical, chemical, and biological-based technology. For a more environmentally friendly process that is low cost, produces less sludge, and needs a lesser amount of chemicals, biological treatment is preferable technology. To get maximum effectiveness and efficiency, integrations/ hybrids consisting of several technologies are commonly used. This chapter is dedicated to exploring the potential of biological technology to remove dyes from wastewater, especially dyes used in textile industries. This chapter briefly discusses dyes' characteristics, their utilization, and toxicity. Deeper reviews about the biodegradation potential of dyes are elaborated, along with a discussion about biodegradation mechanisms and reviews of either lab-scale or full-scale applications of biological-based technology for dyes treatment. Lastly, this chapter also gives future insight into the biological treatment of dyes.&nbsp

Sustainable wastewater treatment necessitates the application of natural and green material in the approach. Thus, selecting a natural coagulant in wastewater treatment is a crucial step to prevent secondary environmental pollution due to residual inorganic coagulant in treated effluent. Present study investigated the application of Musa paradisiaca (banana) peels in domestic wastewater treatment. From the experimental results, the banana peels were found to have a higher yield with lower moisture content compared to the other fruit wastes. The surface charge of the banana peels was +6.53 meq/g MLSS while the recorded protein composition was 0.248 mg/L. The scanning electron microscopy (SEM) showed that banana peels has rough and pore surfaces compared to the others fruit wastes. At optimum conditions of 50 mg/L dosages, pH 4, and 100 rpm of agitational speed, the maximum turbidity removal of up to 89.9% with initial turbidity of 76 NTU was obtained. The banana peel was also evidenced in efficiently removing COD and NH4-N from domestic wastewater up to 80.0% and 62.5%, respectively. Overall, the findings suggested that Musa paradisiaca (banana) peels is efficient and suitable to be applied as the natural coagulant in treating domestic wastewater.

Microbial electrolysis cells (MECs) are a new bio-electrochemical method for converting organic matter to hydrogen gas (H2). Palm oil mill effluent (POME) is hazardous wastewater that is mostly formed during the crude oil extraction process in the palm oil industry. In the present study, POME was used in the MEC system for hydrogen generation as a feasible treatment technology. To enhance biohydrogen generation from POME in the MEC, an empirical model was generated using response surface methodology (RSM). A central composite design (CCD) was utilized to perform twenty experimental runs of MEC given three important variables, namely incubation temperature, initial pH, and influent dilution rate. Experimental results from CCD showed that an average value of 1.16 m3 H2/m3 d for maximum hydrogen production rate (HPR) was produced. A second-order polynomial model was adjusted to the experimental results from CCD. The regression model showed that the quadratic term of all variables tested had a highly significant effect (P

Pharmaceutical wastewaters presently remain as one of the primary roots of environmental pollution. The current study mainly concentrated on removing cefazolin (CEZ) from pharmaceutical wastewater employing the electrocoagulation (EC) process using iron electrodes. The EC experimental conditions were achieved by using response surface methodology (RSM) with an efficiency of 85.65% under optimal working conditions of pH = 8.0, current density (16 mA/cm2), initial CEZ concentration (25 mg/L), and inter-electrode distance (d = 1.0 cm) at an equilibrium electrolysis time of 40 min. The experimental results obtained were in good agreement with the predicted CEZ removal efficiency of 86.7%. Besides, Analysis of variance (ANOVA) revealed that the experimental model was best suited to a second-order polynomial equation, with an R2 value of 0.92. Moreover, the fisher's F-value of 13.67 and low probability value (p

The discharge of phosphorus from urban and industrial wastewater into water bodies causes eutrophication and algae blooms. What it seems essential is that treatment of such wastewater before its di...

Acacia nilotica biomass was used to prepare activated carbon (ANAC-800) through pyrolysis at 800oC. The ANAC-800 was used as adsorbent for the fluoride sequestration in a batch and continuous column systems. The surface morphology, elemental composition as well as particle size distribution of the adsorbent was investigated with Scanning Electron Microscopy (SEM), Elemental and Particle Size Analyzers. What’s more, the influence of initial fluoride concentrations, column packing height and the flow rate on the column efficiency were examine while the efficiency of batch process as a function of contact time and temperature was also investigated. It was found that the kinetic of the process was best fitted with second order model, while the mechanism was best explained by interparticle diffusion model. In addition, the Langmuir Isotherm model showed that the maximum monolayer adsorption capacity of fluoride removal was 71.93 mg/g. The breakthrough curve and column data were well modelled by Adams-Bohart, Yoon-Nelson and Clark model. The models were judged using Akaike Information Criteria (AIC) values after statistical evaluation. ANAC-800 removed fluoride from aqueous solution comparably higher than other adsorbent in its category in batch and continuous column systems.

This study was aimed to study the potential of biogas (methane) production from vinasse wastewater in real full-scale application using a two-stage sequencing Up-flow High Rate Anaerobic Reactor (UHRAR), with effluent recirculation and substrate modification. Batch experiment was initially conducted prior full-scale application experiment. Batch experiment was done with experimental condition variable: undiluted sample (pH 6) and diluted samples (pH: 5; 6 and 7). pH and methane production were observed for 50 days. Full-scale application was carried out in two-stage UHRAR reactors with volume 60 m3, HRT 40 d and OLR 60.1 – 104 kg COD/m3.d. Observation was lasted for 32 d. Result from batch experiment showed that diluted samples achieved higher COD degradation and methane generation than undiluted sample. The optimum condition occurred at pH 7, with theoretical methane yield of 7.51 – 10.64 L CH4 per kg COD. While in full scale application, at day 32, COD removal was 71% (69.1 kg COD/d removed), with methane production was 36.72 m3 CH4/d. Methane production per COD removed was 0.53 m3 CH4/kg COD.d. Substrate modification and effluent recirculation could improve the substrate biodegradability, maintain microbial diversity and enrich nutrients in the reactor.

Bioelectrochemical systems (BES) have the potential to be used in a variety of applications such as waste biorefinery, pollutants removal, CO

© 2022 The AuthorsThe rapidly expanding global energy demand is forcing a release of regulated pollutants into water that is threatening human health. Among various wastewater remediating processes, electrocoagulation (EC) has scored a monumental success over conventional processes because it combines coagulation, sedimentation, floatation and electrochemical oxidation processes that can effectively decimate numerous stubborn pollutants. The EC processes have gained some attention through various academic and industrial publications, however critical evaluation of EC processes, choices of EC processes for various pollutants, process parameters, mechanisms, commercial EC technologies and performance enhancement via other degradation processes (DPs) integration have not been comprehensively covered to date. Therefore, the major objective of this paper is to provide a comprehensive review of 20 years of literature covering EC fundamentals, key process factors for a reactor design, process implementation, current challenges and performance enhancement by coupling EC with pivotal pollutant DPs including, electro/photo-Fenton (E/P–F), photocatalysis, sono-chemical treatment, ozonation, indirect electrochemical/advanced oxidation (AO), and biosorption that have substantially reduced metals, pathogens, toxic compound BOD, COD, colors in wastewater. The results suggest that the optimum treatment time, current density, pulse frequency, shaking speed and spaced electrode improve the pollutants removal efficiency. An elegant process design can prevent electrode passivation which is a critical limitation of EC technology. EC coupling (up or downstream) with other DPs has resulted in the removal of organic pollutants and heavy metals with a 20% improved efficiency by EC-EF, removal of 85.5% suspended solid, 76.2% turbidity, 88.9% BOD, 79.7% COD and 93% color by EC-electroflotation, 100% decolorization by EC-electrochemical-AO, reduction of 78% COD, 81% BOD, 97% color by EC-ozonation and removal of 94% ammonia, 94% BOD, 95% turbidity, >98% phosphorus by aerated EC and peroxicoagulation. The major wastewater purification achievements, future potential and challenges are described to model the future EC integrated systems.

The continual discharge of emerging inorganic pollutants into natural aquatic systems and their negative effects on the environment have motivated the researchers to explore and develop clean and efficient water treatment strategies. Electrocoagulation (EC) is a rapid and promising pollutant removal approach that does not require any chemical additives or complicated process management. Therefore, inorganic pollutant treatment via the EC process is considered one of the most feasible processes. The potential developments of EC process may make the process a wise choice for water treatment in the future. Thus, the present study mainly focuses on the use of EC technology to remove nutrients and other emerging inorganic pollutants from water medium. The operating factors that influence EC process efficiency are explained. The major advancement of the EC technique as well as field-implemented units are also discussed. Overall, this study mainly focuses on emerging issues, present advancements, and techno-economic considerations in EC process.

While the potable water disinfection regimen has significantly reduced waterborne diseases, development of disinfection byproducts (DBP) during this process has brought a global threat to the environment and human health. The most notorious water pollutant, humic acid (HA), transforms into carcinogenic byproducts during the disinfection process (chlorination) of water treatment. HA removal methods are neither economic nor widely available. This study addresses the most urgent global issue of HA removal by developing an innovative and self-regenerative process based on a low-cost and self-regenerative calf bone char (CBC) that removed 92.1-100% of HA. CBC-based HA removal has not been described yet. The developed CBC, as a super adsorbent of HA, was initially characterized by a scanning electron microscope. Various parameters of adsorption/desorption and self-regeneration of CBC adsorbent were experimentally determined. Results show that prepared CBC with a 112 m

The natural product Catharanthus roseus and Lawsonia inermis leaf extract enhancement in the anti-corrosion potential green corrosion inhibitor (GIC) for Bacillus oleronius EN9 biofilm forms on mild steel (MS) in re-circulating water environment is demonstrated. This re-circulating water was enhancing the corrosion due to the temperature, pH, salinity, and chloride. Therefore, we need to improve the performance of the inhibitors. The chosen GIC inhibition was examined by antibacterial assay, weight loss, surface, and electrochemical analysis. L. inermis has shown the antibacterial activity (75%) against the corrosive bacteria Bacillus oleronius than the C. roseus (44%) optimum concentration of 20 ppm. L. inermis was selected for further studies and it reduces the corrosion rate up to 75 % in the 1% NaCl system. Scanning electron microscopy confirms the formation of the protective film on MS and GC–MS confirmed the presence of complex molecules of L. inermis. Therefore, the current work concluded that green corrosion inhibitor is suitable for the inhibition of biocorrosion of MS in the re-circulating system and a promising alternative for chemical inhibitor.

A novel nanomaterial, bacterial cellulose (BC), has become noteworthy recently due to its better physicochemical properties and biodegradability, which are desirable for various applications. Since cost is a significant limitation in the production of cellulose, current efforts are focused on the use of industrial waste as a cost-effective substrate for the synthesis of BC or microbial cellulose. The utilization of industrial wastes and byproduct streams as fermentation media could improve the cost-competitiveness of BC production. This paper examines the feasibility of using typical wastes generated by industry sectors as sources of nutrients (carbon and nitrogen) for the commercial-scale production of BC. Numerous preliminary findings in the literature data have revealed the potential to yield a high concentration of BC from various industrial wastes. These findings indicated the need to optimize culture conditions, aiming for improved large-scale production of BC from waste streams.

Electrocoagulation (EC) is an excellent and promising technology in wastewater treatment, as it combines the benefits of coagulation, flotation, and electrochemistry. During the last decade, extensive researches have focused on removal of emerging contaminants by using electrocoagualtion, due to its several advantages like compactness, cost-effectiveness, efficiency, low sludge production, and eco-friendness. Emerging contaminants (ECs) are micropollutants found in trace amounts that discharging into conventional wastewater treatment (WWT) plants entering surface waters and imposing a high threat to human and aquatic life. Various studies reveal that about 90% of emerging contaminants are disposed unscientifically into water bodies, creating problems to public health and environment. The studies on removal of emerging contaminants from wastewater are by global researchers are critically reviewed. The core findings proved that still more research required into optimization of parameters, system design, and economic feasibility to explore the potential of EC combined systems. This review has introduced an innovative collection of current knowledge on electro-coagulation for the removal of emerging contaminants.

The use of renewable energy sources as a substitute for nonrenewable fossil fuels is urgently required. Algae biorefinery platform provides an excellent alternate to overcome future energy problems. However, to let this viable biomass be competent with existing feedstocks, it is necessary to exploit genetic manipulation and improvement in upstream and downstream platforms for optimal bio-product recovery. Furthermore, the techno-economic strategies further maximize metabolites production for biofuel, biohydrogen, and other industrial applications. The experimental methodologies in algal photobioreactor promote high biomass production, enriched in lipid and starch content in limited environmental conditions. This review presents an optimization framework combining genetic manipulation methods to simulate microalgal growth dynamics, understand the complexity of algal biorefinery to scale up, and identify green strategies for techno-economic feasibility of algae for biomass conversion. Overall, the algal biorefinery opens up new possibilities for the valorization of algae biomass and the synthesis of various novel products.

The formation of bulking and foaming in biological wastewater treatment could cause a series of operational issues with biomass and effluent quality, ultimately affect the treatment performance of the system. The essential parameters influencing the growth of bulking and foaming bacteria are comprehensively summarised in this paper. Existing bulking and foaming control approached are critically reviewed and addressed, as well as their drawbacks and limitations. Despite the abundance of information and implementation, a complete control technique for limiting filamentous sludge bulking and foaming remains insufficient. Magnetic field application is emphasised as a viable control strategy in this regard. The present review study provides new insight of this application by comparing the use of magnetic fields to conventional treatments. Future outlooks on the use of magnetic fields to prevent BFB proliferation were also highlighted.

Pharmaceutical wastewater is a frequent kind of wastewater with high quantities of organic pollutants, although little research has been done in the area. Pharmaceutical wastewaters containing antibiotics and high salinity may impair traditional biological treatment, resulting in the propagation of antibiotic resistance genes. The potential for advanced oxidation processes (AOPs) to break down hazardous substances instead of present techniques that essentially transfer contaminants from wastewater to sludge, a membrane filter, or an adsorbent has attracted interest. Among a variety of AOPs, electrochemical systems are a feasible choice for treating pharmaceutical wastewater. Many electrochemical approaches exist now to remediate rivers polluted by refractory organic contaminants, like pharmaceutical micro-pollutants, which have become a severe environmental problem. The first part of this investigation provides the bibliometric analysis of the title search from 1970 to 2021 for keywords such as wastewater and electrochemical. We have provided information on relations between keywords, countries, and journals based on three fields plot, inter-country co-authorship network analysis, and co-occurrence network visualization. The second part introduces electrochemical water treatment approaches customized to these very distinct discarded flows, containing how processes, electrode materials, and operating conditions influence the results (with selective highlighting cathode reduction and anodic oxidation). This section looks at how electrochemistry may be utilized with typical treatment approaches to improve the integrated system's overall efficiency. We discuss how electrochemical cells might be beneficial and what compromises to consider when putting them into practice. We wrap up our analysis with a discussion of known technical obstacles and suggestions for further research.

As a renewable energy carrier, hydrogen gains international recognition, with the ability to substitute fossil fuels. A state-of-the-art technology called a microbial electrolysis cell (MEC) can produce viable, clean hydrogen energy and also treat wastewater using various renewable carbon sources. The key substrates tested include wastewater, fermentable, and nonfermentable organic effluents. This chapter mainly discuss the scientific fundamentals of MEC technology, including its operating principles, thermodynamics, and electron transfer mechanisms. This chapter also discusses the nutrient, heavy metal removal, and integrated technologies used for higher hydrogen production.