Treatment Reuse Research Articles

Improving the Performance of the Reverse Osmosis Process with Fiber Filter and Ultrafiltration: Promoting Municipal Sewage Reclamation and Reuse for Industrial Processes

Wastewater reuse presents a promising solution to the growing need for the sustainable use of available water resources. The reclamation of municipal sewage through reverse osmosis can be applied for diverse uses to alleviate chronic water scarcity. In this study, a pilot plant was fabricated to measure the efficiency and the costs that are associated with pretreatment by the fiber filtration and ultrafiltration of secondary effluent from a water resource recovery facility in Taiwan. The results of this dual-membrane process meet the quantity and quality standards for industrial reuse. The pretreatment produced feedwater with a silt density index (SDI15) lower than 4.1, and with average turbidity removal rates of 42.7% (fiber filtration) and 99.2% (ultrafiltration). Following reverse osmosis, a 97.9% rejection of the electrolyte conductivity was achieved in the reclaimed water. The fouling of the membranes was controlled through the application of intensive backwash, chemically enhanced backflushing, and cleaning in place. The proposed system improves the feasibility, reliability, and economy of the dual-membrane process as a tertiary treatment for safe water reuse, and it thereby demonstrates that this technology has reached maturity for the full-scale implementation of sustainable water reuse.

An assessment of technological development and applications of decentralized water reuse: A critical review and conceptual framework

AbstractRapid development, urbanization, and population growth have contributed to water stress in many parts of the world. As freshwater sources are finite, it is essential to source for alternatives to ensure water security. Reclamation of non‐conventional water sources (i.e., rainwater and greywater) can be a viable alternative to alleviate water stress. In this work, various laboratory, pre‐commercialization scale, and commercialized products for rainwater harvesting and greywater treatment and reuse were reviewed. As a result, a conceptual framework is proposed to provide an overview on the applicability of technologies under various settings, which were mapped against the intended use of treated water and the potential for water supply expansion. This conceptual framework could aid decision makers in deciding on a suitable decentralized solution for water reclamation depending on limiting criteria. Decentralized systems of rainwater harvesting and greywater treatment for reuse are going to be crucial in reducing the dependence on the centralized water supply.This article is categorized under: Engineering Water > Planning Water Water and Life > Conservation, Management, and Awareness Science of Water > Water Quality

Sulfite-activated ferrate for water reuse applications

Ferrate is a promising, emerging water treatment technology. However, there has been limited research on the application of ferrate in a water reuse paradigm. Recent literature has shown that ferrate oxidation of target contaminants could be improved by “activation” with the addition of reductants or acid. This study examined the impact of sulfite-activated ferrate in laboratory water matrix and spiked municipal wastewater effluents with the goal of transforming organic contaminants of concern (e.g., 1,4-dioxane) and inactivating pathogenic organisms. Additionally, the formation of brominated disinfection byproducts by activated ferrate were examined and a proposed reaction pathway for byproduct formation is presented. In particular, the relative importance of reaction intermediates is discussed. This represents the first activated ferrate study to examine 1,4-dioxane transformation, disinfection, and brominated byproduct formation. Results presented show that the sub-stoichiometric ([Sulfite]:[Ferrate] = 0.5) activated ferrate treatment approach can oxidize recalcitrant contaminants by >50%, achieve >4-log inactivation of pathogens, and have relatively limited generation of brominated byproducts. However, stoichiometrically excessive ([Sulfite]:[Ferrate] = 4.0) activation showed decreased performance with decreased disinfection and increased risk of by-product formation. In general, our results indicate that sub-stoichiometric sulfite-activated ferrate seems a viable alternative technology for various modes of water reuse treatment.

PFAS Complicate Potable Reuse and Advanced Treatment

<scp>PFAS</scp> Complicate Potable Reuse and Advanced Treatment

Comparative Evaluation of Membrane Filtration on the Tertiary Treatment of Synthetic Secondary Effluent

Wastewater reuse is essential for sustainable water management. However, it requires tertiary treatment within the plant to ensure suitable water quality. This project aims to investigate the comparative performance of conventional tertiary treatment (sand filtration) against membrane filtration technology to demonstrate the viability of membrane treatment for wastewater reuse. Sand filtration along with two membrane filtrations, Nano Filtration (NF) and Reverse Osmosis (RO), were tested for their efficiency in removing the target pollutants: chromium, phosphate, and UV-254 from secondary effluent. Standard medium-sized laboratory setups were used. Synthetic secondary effluent was used for comparison among the different treatment processes. The synthetic effluent was compared to the real wastewater to demonstrate the reliability of using synthetic effluent. Evaluation of the role of time and pressure on the treatment efficiency was also examined. Based on the experimental results, RO had the highest removal efficiency for all pollutants with more than 90% removal. The experimental results also showed that synthetic wastewater was reliable in representing the treatability of real wastewater. Time did not seem to have an impact on the quality of filtration. Moreover, as pressure increased there was a slight increase in the efficiency. This trend was observed in all pollutants except UV-254. ANOVA showed different results of the effect of pressure on the removal efficiency in both RO and NF as well as time in NF.

Water reuse to free up freshwater for higher‐value use and increase climate resilience and water productivity

AbstractThe impact of climate change on the availability of water affects all types of land use and sectors. This complexity calls for integrated water resources management and negotiations between sectors on the most important, cost‐effective, and productive allocation of water where it is a limited resource. This reflection paper shows examples of adaptation efforts to water scarcity at a scale where gains in water productivity can be derived from inter‐sectoral water reuse and wastewater–freshwater swaps, complementing other water scarcity coping strategies (water savings, long‐distance transfer, and desalination). Wastewater treatment for reuse offers opportunities across scales as it allows, for example, donor regions to be compensated with reclaimed water for the release of freshwater for higher‐value use, increasing overall economic water productivity in this way. In such water swaps, farmers are compensated with higher water volumes in exchange for higher quality. The reuse of water between sectors offers opportunities to (i) expand the traditional (agricultural) water productivity concept and (ii) significantly increase water productivity at the system level. While rural–urban water reallocation can help mitigate the impacts of climate change, compensating farmers with reclaimed water remains limited for the reasons discussed in the paper.

Characteristics of the formation and toxicity index of nine newly identified brominated disinfection byproducts during wastewater ozonation

Ozonation plays an important role in wastewater treatment for reuse. However, the toxicity of wastewater treated with ozone considerably increases with bromide (Br−) concentration >100 μg/L. Nine newly identified brominated disinfection byproducts (Br-DBPs) that are highly toxic in ozonated Br−-containing wastewater were found in our recent work, including 2-bromostyrene, 1-bromo-1-phenylethylene, 2-bromobenzaldehyde, 3-bromobenzaldehyde, 4-bromobenzaldehyde, 2-bromophenylacetonitrile, 3-bromophenylacetonitrile, 4-bromophenylacetonitrile, and 2,4,6-tribromophenol. In the present study, the formation and calculated toxicity index of the nine newly identified Br-DBPs were evaluated. The correlations between the water quality index and the formation of nine Br-DBPs were also analyzed. With the increase of ozone dosage, the concentrations of bromostyrenes, 3-bromobenzaldehyde, 4-bromobenzaldehyde, 2-bromophenylacetonitrile, and 2,4,6-tribromophenyl in the ozonated samples gradually increased. With the increase of Br− concentration, the concentrations of bromostyrene, 2-bromobenzaldehyde, and 2,4,6-tribromophenol gradually increased. With the increase of NH4+ concentration, the concentrations of bromophenylacetonitriles gradually increased. Among the nine Br-DBPs, the bromophenylacetonitriles and 2,4,6-tribromophenol contributed the most to the cytotoxicity index, 2,4,6-tribromophenol and bromostyrenes contributed the most to the genotoxicity index, and bromophenylacetonitriles and bromostyrenes contributed the most to the oxidative damage index. The dissolved organic carbon levels strongly correlated with the formation of 3-bromophenylacetonitrile and 4-bromophenylacetonitrile, and the fluorescence I–V region intensity integral was correlated with the formation of 4-bromobenzaldehyde and 2,4,6-tribromophenol. The results of the present study clarified the formation potential of the nine widely existing newly identified Br-DBPs, confirmed the high calculated toxicity indices, and are of great value for future research on Br-DBPs.

High Efficiency Regeneration Performance of Exhausted Activated Carbon by Superheated Steam and Comparison with Conventional Chemical Regeneration Method

Spent activated carbon is a common by-product of pollution treatment with granular activated carbon (GAC) adsorption and therefore spent activated carbon treatment for reuse is critical to maximize cost-effectiveness and sustainability. Superheated steam regeneration is a novel treatment technology that uses water vapor and is more energy- and cost-efficient than other thermal regeneration methods. This work has value in that two modes of operation are compared in a small-scale process, whose experiment is well designed to reflect its large-scale process. Our study evaluated the effects of superheated steam regeneration on phenol-saturated activated carbon using a rapid small-scale column test (RSSCT) and evaluated this approach with the conventional chemical regeneration method. Our findings indicated that superheated steam regeneration achieved optimal performance at 500°C for 60 min, whereas chemical regeneration performance was optimal using 4% NaOH coupled with a low flow rate. Based on these observations, cyclic adsorption/regeneration tests were conducted six times. Additionally, differences on the carbon surface after regeneration were explored via scanning electron microscopy (SEM). The results indicated that superheated steam was more efficient and rendered cleaner carbon surfaces.

Characterization of produced water and surrounding surface water in the Permian Basin, the United States

A thorough understanding of produced water (PW) quality is critical to advance the knowledge and tools for effective PW management, treatment, risk assessment, and feasibility for beneficial reuse outside the oil and gas industry. This study provides the first step to better understand PW quality to develop beneficial reuse programs that are protective of human health and the environment. In total, 46 PW samples from unconventional operations in the Permian Basin and ten surface water samples from the Pecos River in New Mexico were collected for quantitative target analyses of more than 300 constituents. Water quality analyses of Pecos River samples could provide context and baseline information for the potential discharge and reuse of treated PW in this area. Temporal PW and river water quality changes were monitored for eight months in 2020. PW samples had total dissolved solids (TDS) concentrations ranging from 100,800–201,500 mg/L. Various mineral salts, metals, oil and grease, volatile and semi-volatile organic compounds, radionuclides, ammonia, hydraulic fracturing additives, and per- and polyfluoroalkyl substances were detected at different concentrations. Chemical characterization of organic compounds found in Pecos River water showed no evidence of PW origin. Isometric log-ratio Na-Cl-Br analysis showed the salinity in the Pecos River samples appeared to be linked to an increase in natural shallow brine inputs. This study outlines baseline analytical information to advance PW research by describing PW and surrounding surface water quality in the Permian Basin that will assist in determining management strategies, treatment methods, potential beneficial reuse applications, and potential environmental impacts specific to intended beneficial use of treated PW.

Crop fertilisation potential of phosphorus in hydrochars produced from sewage sludge

Sewage sludges are a rich underused source of phosphorus (P) which contributes to environmental degradation, yet if recaptured, could return significant amounts of P to agricultural systems. Hydrothermal carbonisation (HTC) can efficiently recover P, with the added ability to transform P species into potentially more desirable forms for direct application to crops. P dynamics in hydrochars have primarily examined P speciation and chemical extractability as indicators of P bioavailability, but few studies directly evaluate the agronomic effectiveness of hydrochars as P fertilisers. As such, there is a clear need to assess the suitability of hydrochar as a source of bioavailable P in plant systems and the influence of HTC synthesis conditions. Response Surface Modelling of HTC synthesis conditions (pH, temperature and time), revealed initial pH significantly influence P distribution. Mild conditions of 180 °C for 30 min at pH 8.0 maximised P recovery (99%) along with carbon (62%) and nitrogen (43%) in hydrochars. Systematic characterisation of hydrochar P by chemical extraction and P L2,3-edge X-ray absorption near edge spectroscopy revealed H2O, NaHCO3 and NaOH- P fractions were significantly (p < 0.05) reduced in all hydrochars, while HCl-P fraction increased with HTC temperatures at pH 7. In contrast, P L2,3-edge XANES spectra were remarkably similar in raw sludges and corresponding hydrochars, regardless of HTC temperature or pH, revealing P was predominantly present as ferric phosphate with some hydroxyapatite. Multiple linear regression modelling suggested a significant relationship between chemical extractability and P bioavailability to wheat present in the raw sludges and hydrochars. This research provides further insight into the potential to use hydrothermal treatment for recovery and agricultural reuse of P, the importance of operational conditions on P transformation and the relationship between P speciation and bioavailability. The value of sewage sludge in a more sustainable global P cycle is also highlighted.

Solar-activated zinc oxide photocatalytic treatment of real oil sands process water: Effect of treatment parameters on naphthenic acids, polyaromatic hydrocarbons and acute toxicity removal

Oil sands process water (OSPW) is an industrial process effluent that contains organic compounds such as naphthenic acids (NAs) and polyaromatic hydrocarbons (PAHs), as well as large quantities of inorganic compounds in its mixture. OSPW requires effective treatment for successful reclamation and water reuse. This study investigated the impact of solar-activated zinc oxide (ZnO) photocatalysis on the degradation and removal of NAs and PAHs in OSPW, as well as the elimination of its acute toxicity. With catalyst particles suspended in the effluent (at 1 g/L) under simulated solar radiation of steady irradiance of ~278 W/m2, more than 99% removal of NAs was achieved after 4 h of treatment, while nearly all PAHs were simultaneously oxidized within the same reaction time. The photocatalytic treatment appeared to selectively convert classical NAs faster than oxidized NAs. Additionally, NAs with higher double-bond equivalents (DBEs) and higher carbon numbers seemed more susceptible to photocatalytic destruction than others. An overall pseudo first-order rate constant of 1.14 × 10−2 min−1, and a fluence-based rate constant of 6.81 × 10−1 m2/MJ were recorded in apparently hydroxyl radicals (OH) and superoxide (O2−) radicals mediated NAs degradation mechanisms. Assessment of the toxicity levels in raw and treated OSPW samples by using Microtox® bioassay indicated that the photocatalytic treatment resulted in ~50% reduction in acute toxicity. Furthermore, we showed that by monitoring the expression levels of key proinflammatory genes using qPCR that treated OSPW significantly reduced the ability of raw OSPW to activate the inflammatory response of immune cells. This indicates that at acute sub-lethal exposure doses, photocatalytic treatment also reduces immunotoxicity. Overall, our results suggest that the ZnO-based photocatalytic degradation of these NAs and PAHs in OSPW could be a significant treatment process aimed at detoxifying OSPW.

Greywater characterization of an Indian household and potential treatment for reuse

• A filtration system with different filter layers was designed. • COD removal efficiency of 85.98%. • BOD removal efficiency of 86.28%. • 94.44% total suspended solids removal efficiency. Inadequate water supplies recall the environmental values of recovery and reuse of limited resources. One of the exciting opportunities in these circumstances is Grey water. Wastewater is generated from household activities like bathing, kitchen sinks, washbasins, and laundry classified as greywater. Inventing a pilot-scale greywater treatment system that treats in-house generated greywater and makes it reusable by assisting the untapped potential of physical methods of greywater purification was the main aim of this study. The study results from greywater samples' characterization from various sources in an Indian middle-class single household with four residents for six months. Moreover, the designing and analyzing of a treatment system applied to treat this in-house generated greywater was conducted. A filtration system with different filter layers was designed. It was found to have a chemical oxygen demand removal efficiency of 85.98%, biochemical oxygen demand removal efficiency of 86.28%, and total suspended solids removal efficiency of 94.44%. The filter system designed in this study describes improved removal efficiency in all respects and gives an idea of the reusability of in-house treated greywater. The study concludes that greywater can be recycled and reused for toilet flushing, gardening, car washing, and firefighting. This practice can also lead to a significant reduction in the consumption of freshwater.

Recycling Spent Graphite Anodes into a Graphite/Graphene Oxide Composite Via Plasma Solution Treatment for Reuse in Lithium-Ion Batteries

Recycling Spent Graphite Anodes into a Graphite/Graphene Oxide Composite Via Plasma Solution Treatment for Reuse in Lithium-Ion Batteries

Nanofiltration membrane processes for water recycling, reuse and product recovery within various industries: A review

Nanofiltration (NF) membrane has been applied for the treatment of wastewater owing to its unique features such as higher selectivity towards divalent/polyvalent ions while allowing permeation for monovalent ions and small molecules of less than 100 Da. Thus, the use of NF in wastewater treatment is promising for water recycling, reuse, and recovery of other valuable products in industrial wastewater treatment. This review highlights the current application of NF for water recycling, reuse, and product recovery within multiple industries such as textile, food, oil and gas, mining, tannery, pharmaceutical as well as pulp and paper industry. The performance of NF either as stand-alone or integrated with other processes for improving the overall treatment efficiency and minimizing membrane issues is discussed. Finally, future perspectives for NF applications in industrial wastewater treatment for water recycling, reuse, and product recovery are discussed.

Chemometric characterization of textile waste waters from different processes

The aim of this work is focused on water quality classification of the textile waste water streams and evaluation of pollution. Data from the chemical characterization of the effluents were elaborated to identify a useful separation in potentially treatment for reuse. This was done with the aim of realizing a full scale characterization of effluents. In the two textile companies analyzed, machineries are used to carry out different production processes such as sizing and desizing, weaving, scouring, bleaching, mercerizing, carbonizing, fulling, dying and finishing. Different process effluents from the same machinery were found to be very diverse in pollution level. 25 and 49 samples of textile waste waters from two different textile companies were analysed and physical chemical measurements were performed. The following physicochemical and chemical water quality parameters were controlled: absorbance measured at three different wavelengths, pH, conductivity, turbidity, total suspended solids, volatile suspended solids, chemical oxygen demand, metals content (Ba, Ca, Cu, Mn, K, Sr, Fe, Al, Na) and total nitrogen content. For&#x0D; handling the results, basic statistical methods for the determination of mean and median values, standard deviations, minimal and maximal values of measured parameters and their mutual correlation coefficients, were performed. Different chemometric methods, namely, principal component analysis (PCA), cluster analysis (CA), and linear discriminant analysis (LDA) were used to find hidden information about textile waste water quality.

A critical review of advanced nanotechnology and hybrid membrane based water recycling, reuse, and wastewater treatment processes

One of the modern challenges is to provide clean and affordable drinking water. Water scarcity is caused by the growing population in the world and pollutants contaminate all remaining water sources. Innovative water treatment solutions have been provided by nanotechnology. Microorganisms, organic suspensions, and inorganic heavy metal ions, among other things, are common water contaminants. Since antiquity, a wide range of water clean-up methods have been employed to address this issue. Breakthroughs in water purification procedures have occurred during the previous four decades, with the most significant one being the use of nanomaterials and nanomembranes. Nanoparticles and nanomembranes (polymeric membranes) have recently been used in engineered materials (TiO2, ZnO, CuO, Ag, CNT's and mixed oxide nanoparticles, for example). Engineered nanomembranes, nanocomposites and nanoparticles have been used in this review article's discussion of water purification technologies. The review also discusses the risk and solutions of using nanoparticles and nanocomposites in the future.

Slaughterhouse Wastewater Treatment: A Review on Recycling and Reuse Possibilities

Slaughterhouses produce a large amount of wastewater, therefore, with respect to the increasing water scarcity, slaughterhouse wastewater (SWW) recycling seems to be a desirable goal. The emerging challenges and opportunities for recycling and reuse have been examined here. The selection of a suitable process for SWW recycling is dependent on the characteristics of the wastewater, the available technology, and the legal requirements. SWW recycling is not operated at a large scale up to date, due to local legal sanitary requirements as well as challenges in technical implementation. Since SWW recycling with single-stage technologies is unlikely, combined processes are examined and evaluated within the scope of this publication. The process combination of dissolved air flotation (DAF) followed by membrane bioreactor (MBR) and, finally, reverse osmosis (RO) as a polishing step seems to be particularly promising. In this way, wastewater treatment for process water reuse could be achieved in theory, as well as in comparable laboratory experiments. Furthermore, it was calculated via the methane production potential that the entire energy demand of wastewater treatment could be covered if the organic fraction of the wastewater was used for biogas production.

Microwave Sintering Rapid Synthesis of Nano/Micron β-SiC from Waste Lithium Battery Graphite and Photovoltaic Silicon to Achieve Carbon Reduction

The paper describes one promising method and approach for the recycling, reuse, and co-resource treatment of waste photovoltaic silicon and lithium battery anode graphite. Specifically, this work considers the preparation of nano/micron silicon carbide (SiC) from waste resources. Using activated carbon as a microwave susceptor over a very short timeframe, this research paper shows that nano/micron β-SiC can be successfully synthesized using microwave sintering technology. The used sintering temperature is significantly faster and more energy-efficient than traditional processes. The research results show that the β-SiC particle growth morphology greatly affected by the microwave sintering time. In a short microwave sintering time, the morphology of the β-SiC product is in the form of nano/micron clusters. The clusters tended to be regenerated into β-SiC nanorods after appropriately extending the microwave sintering time. In the context of heat conversion and resource saving, the comprehensive CO2 emission reduction is significantly higher than that of the traditional SiC production method.

Stormwater treatment for reuse: Current practice and future development – A review

Stormwater harvesting is an effective measure to mitigate flooding risk and pollutant migration in our urban environment with the continuously increasing impermeable faction. Treatment of harvested stormwater also provides the fit-for-purpose water sources as an alternative to potable water supply ensuring the reliability and sustainability of the water management in the living complex. In order to provide the water management decision-maker with a broad range of related technology database and to facilitate the implementation of stormwater harvesting in the future, a comprehensive review was undertaken to understand the corresponding treatment performance, the applicable circumstances of current stormwater treatment and harvesting technologies. Technologies with promising potential for stormwater treatment were also reviewed to investigate the feasibility of being used in an integrated process. The raw stormwater quality and the required quality for different levels of stormwater reuses (irrigation, recreational, and potable) were reviewed and compared. The required level of treatment is defined for different ‘fit-for-purpose’ uses of harvested stormwater. Stormwater biofilter and constructed wetland as the two most advanced and widely used stormwater harvesting and treatment technologies, their main functionality, treatment performance and adequate scale of the application were reviewed based on published peer-reviewed articles and case studies. Excessive microbial effluent that exists in stormwater treated using these two technologies has restricted the stormwater reuse in most cases. Water disinfection technologies developed for wastewater and surface water treatment but with high potential to be used for stormwater treatment have been reviewed. Their feasibility and limitation for stormwater treatment are presented with respect to different levels of fit-for-purpose reuses. Implications for future implementation of stormwater treatment are made on proposing treatment trains that are suitable for different fit-for-purpose stormwater reuses.

Steel slag quality control for road construction aggregates and its environmental impact: case study of Vietnamese steel industry-leaching of heavy metals from steel-making slag.

Steel slag is an industrial by product of steel manufacturing processes and has been widely utilized within civil and construction materials for road materials and environmental remediation in countries like Japan, USA, and European Union nations. However, the current utilization of steel slag in Vietnam is very low mainly because of lack of quality control of slag treatment and chances for reuse of treated steel slag. This paper presents the up to date steel slag production status in Vietnam through the extensive survey and sampling at seven large steel factories. The paper also highlights the environmental and quality control issues of these steel slags to use as road construction aggregates by assessing the heavy metals concentration in the leachate. The basic oxygen furnace (BOF) and electric arc furnace (EAF) slag samples were collected to evaluate leaching properties of metals leached from the slags. The two standardized batch leaching tests of steel slag roadbed material in Japan (JIS K 0058-1) and toxicity characteristics leaching procedure (TCLP-EPA method 1311) were performed to the evaluated the hazardous metals. The results of the leaching test show that almost all of the concentration of the metals in the leached solution does not exceed the National Standard for Industrial Wastewater Discharge (QCVN 40-2011). The pH and parameters such as total chromium, nickel, copper, lead, arsenic, and manganese differ from the two test methods. The acidic conditions employed in the EPA 1311 were not representative of condition excepted during slag reuse in road constructions because in the operation condition of the road, acidic liquid is absent. The leaching test results confirmed that JIS test which uses deionized water with gentle mixing prevents the slag sample from size degradation is suitable for the environmental assessment of steel slag use for roadbed material. This research suggests that the adjustment of pH value prior to disposal or reuse as base materials and official guideline should be promulgate by the authorities to ensure the leachate meet the surface water quality standard.