Effluent Treatment Plant Sludge Research Articles

Harnessing hazardous wastes: the production, characterization, and performance of controlled low strength materials using common effluent treatment plant sludge

India's rapid industrialization has led to an increase in waste generation, necessitating efficient disposal methods. This research addresses this challenge by exploring the use of Common Effluent Treatment Plant (CETP) sludge, a hazardous waste, in the production of Controlled Low-Strength Materials (CLSM). The study aims to mitigate the environmental impacts associated with CETP sludge disposal while providing a sustainable solution. To assess the feasibility of this approach, an experimental program was conducted with variations in the mix ratio of CETP sludge and slag sand, a byproduct of steel production. The properties of the produced CLSM, such as flowability and unconfined compressive strength (UCS), were thoroughly examined using Scanning Electron Microscopy, X-ray Diffraction, and X-ray Fluorescence analyses. The results reveal that the CLSM produced with CETP sludge and slag sand exhibits promising performance, with excellent flowability and UCS values ranging from 1.8 to 5.5 MPa. This research underscores the potential of waste materials in creating sustainable and environmentally friendly construction materials, contributing to effective waste management practices and sustainable industrial growth.

Evaluation of textile effluent treatment plant sludge as supplementary cementitious material in concrete using experimental and machine learning approaches

The growing demand for readymade garments is leading to the production of a large amount of textile effluent sludge (TES) from wastewater treatment plants, which is currently disposed of as backfill, causing land and groundwater contamination. This scenario has prompted researchers to explore the use of industrial waste, such as TES, as a supplementary cementitious material (SCM) to mitigate the carbon footprint of cement production. Therefore, this study aims to investigate the fresh, mechanical, non-destructive characteristics, and predictive modeling of mechanical strengths of TES-based concrete. Machine learning models, including random forest (RF) and artificial neural networks (ANN), were utilized to predict compressive and tensile strengths from various input variables. This study also evaluated the alkalinity, specific gravity, oxide content, and surface area of TES. The findings showed a pH of 9.4 and a CaO content of 33.3 %, indicating TES's potential as an SCM. The research further investigated the properties of concrete with 5–20 % cement-replaced TES, using a total binder content of 488.1 kg/m3 and a water-binder ratio of 0.32. The fresh state properties of the 5–15 % TES incorporated concrete produced normal density concrete, with a slump of 100 ± 20 mm, Kelly ball penetration of 45 ± 7 mm, a compaction factor of 0.92 ± 0.05, and a fresh density of 2464 ± 152 kg/m3. At 28 days, concrete with 15 % TES replacement showed a compressive strength of 25.6 MPa and a tensile strength of 2.88 MPa, achieving 76 % of the strength activity index and 72 % of the relative tensile strength. However, the 15 % TES concrete displayed a water permeability coefficient of 4.4 × 10−12 m/s and an electrical resistivity of 31.5 kΩ cm, compared to the control mix's 2.0 × 10−12 m/s and 37.7 kΩ cm. However, the hardened properties declined significantly after replacing 15 % of cement with TES. The mechanical properties were also estimated using ultra pulse velocity and rebound hammer tests, showing a coefficient of determination (R2) higher than 0.87. The RF model demonstrated superior performance with an R2 value of 0.8802 for compressive strength and 0.8518 for tensile strength, outperforming the ANN model's R2 values of 0.8126 and 0.695, respectively. Scanning electron microscopy confirmed the consistent development of hydration products in the TES-enhanced concrete samples.

Characterization of Denim Effluent Treatment Plant Sludge and its Influence on Concrete Hardened Properties

Characterization of Denim Effluent Treatment Plant Sludge and its Influence on Concrete Hardened Properties

Characterization of textile effluent treatment plant sludge and its industrial application in fired clay bricks with health risk assessment

The textile industry in Bangladesh faces environmental and health challenges due to the disposal of solid waste from Effluent Treatment Plants (ETPs). To address this issue, a study was conducted using soil from a brick industry near Dhaka, amending it with varying amounts of dry sludge to create clay bricks. The original soil had a loam texture and medium plasticity. The research found that adding 9 wt% of sludge resulted in Grade A commercial bricks with a compressive strength of 15.33 MPa and water absorption of 13.33 wt%, meeting BDS 208 standards. However, these sludge-incorporated bricks experienced more shrinkage during the burning process due to organic content, requiring additional soil to maintain conventional dimensions. Also, to assess the health hazards of these sludge-incorporated bricks, a leaching test was performed, revealing that no toxic heavy metals (Pb, Cd, Cr, Cu, Ni, and Zn) in the leachate exceeded the limits set by the United States Environmental Protection Agency (USEPA). The study indicates that textile ETP sludge can serve as a sustainable raw material for bricks, potentially reducing the environmental burden caused by textile sludge disposal by 28.75%. This innovative approach offers a promising solution to both environmental and health concerns associated with textile waste in Bangladesh's industrial sector.

Utilization of textile and tannery sludges in cement mortar

The aim of this study is to investigate the characteristics of Textile ETP and Tannery sludges and strength characteristics of cement-sludge mortar. The textile Effluent Treatment Plant (ETP) and tannery sludges have the potential to become a serious environmental burden for Bangladesh in the future because of their high rate of generation, with a very limited safe disposal option. On the other hand, day by day the demand and price of cement are increasing. This study was devoted to evaluate the technical feasibility of utilizing textile ETP and tannery sludges in cement mortar both as separate and mixed modes. An attempt was taken to replace 5%, 10%, 15% and 20% by weight of cement in mortar with textile ETP and tannery sludges both as a separate and mixed modes. To evaluate the characteristics of the textile ETP and tannery sludges, the pH, moisture content, organic matter content, chemical composition (XRF), TCLP (Heavy Metal) tests were studied. The initial and final setting time, compressive strength, tensile strength, and water absorption of mortar by partial replacement of cement by textile ETP and tannery sludges both as separate and mixed modes were studied to evaluate the properties of cement-sludge mortar. It was found that the textile ETP and tannery sludges both as separate and mixed modes can be a replacement of cement up to 10% in cement mortar and can be used for the purposes of S-type of mortar. The textile ETP sludge as a separate and mixed modes of the sludges can be a replacement of cement up to 20% and can be used for the purposes of N-type of mortar.

Utilization of Domestic Wastewater and Textile Effluent Treatment Plant Sludge as Brick Material

Utilization of Domestic Wastewater and Textile Effluent Treatment Plant Sludge as Brick Material

Comprehensive assessment of ceramic ETP sludge waste as a SCM for the production of concrete

With the intention of improving sustainability of ceramic manufacturing and construction industry this study evaluates the use of ceramic effluent treatment plant (ETP) sludge as a supplementary cementitious material (SCM). ETP sludge which was source from the manufacturing plant of vitrified porcelain stoneware tiles had a specific surface area of 22858 cm2/g. This waste was used to replace cement in steps of 10% from 0 to 50% for the manufacture of concrete with two different w/b ratios of 0.35 and 0.45. Tests like slump, hardened density, compressive, flexural, split tensile strengths, resistance to water penetration and abrasion, drying shrinkage were evaluated. The results indicated that at a minimal substitution rate of 10%, ETP sludge improved workability and apparent density of the mixes. Mechanical properties also increased marginally at the same utilization ratio. This improvement in properties of the mixes were due to the waste materials cohesivity and void filling capabilities. However, the water absorption capacity increased with increase in usage of ETP sludge along with a corresponding reduction in abrasion resistance. Drying shrinkage was lesser for mixes with up to 30% usage of the waste. Retrospectively, these results were verified using various microstructural analysis and was understood that ETP sludge was not pozzolanic and its excessive usage diluted the hydration products, leading to the fall in all the properties. Hence it is recommended that ceramic waste procured from the manufacturing stage can be used to replace ordinary Portland cement (OPC) to a maximum of 10% for the manufacture of medium strength concrete.

Metagenomics: An Approach for Unraveling the Community Structure and Functional Potential of Activated Sludge of a Common Effluent Treatment Plant

The common effluent treatment plant (CETP) located at Baddi treats the industrial effluent from various industries, leading to the pooling of a diverse range of substrates and metabolites. The nutrient loading and its availability decide the balance of the microbial community and its diversity. The samples thus collected from the activated sludge (BS14) of CETP and Sirsa river (SR1) from the vicinity of CETP effluent discharge were processed for the whole metagenome analysis to reveal the microbial community and its functional potential. The taxonomic classification of the BS14 sample showed the dominance of the bacterial community with 96% of abundance, whereas the SR1 was populated by eukaryotes representing 50.4% of the community of SR1. The bacterial community of SR1 was constituted of 47.2%. The functional analysis of BS14 and SR1 with GhostKOALA against the KEGG database assigned 43.7% and 27.8% of the open reading frames (ORFs) with functions. It revealed the xenobiotic degradation modules with complete pathways along with resistance against the beta-lactams. The analysis with the comprehensive antibiotic resistance database (CARD) revealed 33 and 32 unique types of antimicrobial resistance in BS14 and SR1, respectively. Both the samples were dominated by the beta-lactam resistance genes. The carbohydrate-active enzyme (CAZy) database assigned a total of 6,611 and 2,941 active enzymes to BS14 and SR1, respectively. In contrast, the glycosyl hydrolases (GH) and glycosyltransferases (GT) class of enzymes were found to be abundant in both the samples as compared with polysaccharide lyases (PL), auxiliary activities (AA), carbohydrate esterases (CE), and carbohydrate-binding module (CBM).

Equilibrium, Kinetic and Thermodynamic Studies of Malachite Green Dye Removal using Activated Sludge from Common Effluent Treatment Plant

Disposal of industrial effluents containing synthetic dyes causes a potential hazard to the land and environment and therefore dyes need to be removed before disposal. In the present study, combined effluent treatment plant (CETP) sludge was activated at 200° C for 1 hour and used as an adsorbent for the removal of malachite green dye from wastewater. The adsorbent was characterized by XRF, SEM, XRD and FTIR. Batch studies were carried out under various experimental conditions by varying contact time, dye concentration, adsorption dose, pH and temperature to assess the potentiality of activated sludge for the removal of malachite green dye from wastewater. The results revealed that the removal of malachite green dye was strongly pH dependent and maximum dye removal was observed at equilibrium pH of 8.0. Optimum adsorbent dose and contact time were found to be 10 g/l and 180 minutes respectively. Thermodynamic studies showed the spontaneous and endothermic nature of the adsorption. Adsorption data have also been correlated with different isotherm models. Hence activated sludge can be used as an effective adsorbent for the removal of malachite green dye from wastewater. It could be considered as good replacement of commercially available adsorbent like zeolites, activated carbon etc. due to its significant low cost and high sorption efficiency.

Solubilization of rock phosphate by phosphate solubilizing bacteria isolated from effluent treatment plant sludge of a fertilizer plant.

This study evaluates the efficiency of Phosphate solubilizing bacteria isolated from Effluent Treatment Plant sludge of Paradeep Phosphate Limited, Odisha, India, to solubilize rock phosphate (RP) and the mechanism and structural changes during solubilization investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Out of 13 bacterial isolates, Bacillus cereus S0B4, Solibacillus isronensis S0B8, and Bacillus amyloliquefaciens S0B17 strains were found to be the best RP solubilizers. This is the first report on S. isronensis S0B8 with the ability to solubilize RP. In particular, the potent strain B. cereus S0B4 showed maximum soluble P (338.5mg/L) on the 7th day. Negative correlations (r = -0.70; p ≤ 0.01) were observed between soluble P concentration and pH, whereas positive correlation exists with the growth of B. cereus S0B4 (r = 0.91, p ≤ 0.01), S. isronensis S0B8 (r = 0.75, p ≤ 0.01), and B. amyloliquefaciens S0B17 (r = 0.77, p ≤ 0.01) respectively. The P release kinetics followed the 1st order model well (R2 = 0.8001-0.8503). It seems that H+ ions and organic anions released from the organic acids are major factors responsible for RP solubilization. The SEM observations demonstrate that B. cereus S0B4 corroded the RP surface significantly due to the proton attack. The XRD analysis confirms that the intensity of all mineral peaks decreases after treatment with B. cereus S0B4. The FTIR analysis indicated a significant decrease of calcite and fluorapatite's vibrational bands with the disappearance of quartz.

Hydrothermal Carbonization of Paper Mill ETP Sludge and Assessing its Potential Application in Agriculture

Effluent Treatment Plant Sludge (ETPS) from pulp and paper mill is produced in larger quantities and its disposal has the major problem faced by the industries. The conversion of paper mill sludge into hydrochar through the process of Hydro Thermal Carbonization (HTC) has wider opportunities in agriculture. This study explored the optimization processes which influence the preparation of hydrochar from ETPS through the approaches of Response Surface Methodology (RSM). The optimized temperature and time were 220 °C and 4 hours, respectively for hydrochar production based on higher carbon and nitrogen content. The hydrochar and ETPS was characterized using Scanning Electron Microscopy (SEM), Brunauer Emmett Teller (BET) surface area and Fourier Transform Infra-Red Spectroscopy (FTIR) for its structural morphology. Based on the optimized parameters, the hydrochar was produced and used in the pot culture experiment to study the impact of the hydrochar on bhendi (Abelmoschus esculentus) crop growth. Different concentrations of hydrochar were applied as basal in the pot. The treatment with 4% hydrochar germinated first show the good shoot and root length and 11% increase in germination percentage and 22% increase in vigour index when compared with control due to its higher nutritives which is on par with the results of 5% hydrochar.

Sustainable building materials using textile effluent treatment plant sludge: a review

A huge quantity of textile effluent sludge is generated from 21 076 textile units of India and dumped in large areas, leading to contamination of soil, surface water and groundwater. Hence, effective management of this sludge is important for its reuse and safe disposal. Considering the utilization of this waste in construction activities, the current paper explores the potential of textile sludge produced from textile industry effluent treatment plants. Many researchers have attempted to reuse this sludge for the development of sustainable construction materials and suggested its optimum usage as a partial substitution for fine aggregate, cement and clay with or without additives for the manufacturing of non-structural building components. This paper provides a critical review of the production of non-structural elements – namely, sustainable building blocks, clay bricks, mortar and paver blocks – using textile effluent treatment plant sludge and recommends optimum ranges of 5–30, 5–40, 5–50 and 20–40%, respectively. The prominent gaps are suggested as the outcome of studies such as techno-economic feasibility of the product, thermal and energy building simulation along with the life-cycle assessment and fatigue life assessment of the developed paver blocks.

Synthesis of value-added materials from the sewage sludge of cosmetics industry effluent treatment plant

In this work, biochar and bio-oil were produced from the sewage sludge of cosmetics industry effluent treatment plant via pyrolysis under N2 atmosphere, at 500 and 600 °C and 30 and 60 min. The biochar presented micrometric particles with a porous structure, with a surface area between 203 and 231 m2 g–1 and amorphous aspect containing crystalline quartz structures. The superior calorific power (SCP) for different biochar was 5.9–7.6 MJ kg−1. Bio-oils presented fatty acids, alcohols and esters with long aliphatic chains as main constituents. The SCP of these materials showed a high value (41 MJ kg−1), with the possibility to be used as a precursor for the biofuels production. The biochar, was applied as an adsorbent for the methylene blue (MB) dye from aqueous system. The adsorption parameters such as contact time (0–120 min), adsorbent dosage (0.25–1.0 g L−1) and initial pH (5–9.5) were studied. Kinetics and adsorption isotherm studies were also carried out. Pseudo-second order and Langmuir isotherm models fit the data better, showing adsorption maximum amount of 51 mg g−1 at 45 °C. The MB removal by biochar is an endothermic process and the material can be reactivated and reused. From the results, it can be concluded that the sludge from the cosmetic industry can be used as raw material to obtain new products with added value, such as biochar and bio-oil.

Investigating leachate decontamination and biomethane augmentation through Co-disposal of paper mill sludge with municipal solid waste in simulated anaerobic landfill bioreactors

The study aims to investigate the feasibility of anaerobic co-landfilling of effluent treatment plant sludge (ETPS) from paper mill and municipal solid waste (MSW) in prismoidal shaped simulated anaerobic landfill bioreactors. Both ETPS and MSW were co-disposed in 0:100 (R1), 25:75 (R2), 50:50 (R3) and 75:25 (R4) ratios. Periodic assessments of leachate characteristics and biomethane production were carried out for 300 days. ETPS co-disposal with MSW showed considerable reduction in biochemical oxygen demand of leachate (R2: 95.9%, R3: 97.5% and R4: 93.2%). Moreover, cumulative methane gas generations were 2.974, 6.085 and 4.653 times more in R2, R3 and R4 bioreactors as compared to R1. Gompertz growth model was found in well-fitting for methane generation with the observed data. Correlogram plotted among leachate parameters exhibited exclusive relationships and justified leachate trends. This simulation of co-landfilling could be baseline study for the implementation of technology at pilot scale.

Energy generation from effluent treatment plant sludge: Design of bioreactor

The sludge generated from physical, chemical, and biological treatment of sewage and industrial wastewater is a serious problem. It is becoming a major environmental problem with the increase in urbanization & industrialization. The sludge generated contains a vast spectrum of organic, inorganic chemicals & pathogens. Presently the sludge is dewatered and disposed of as landfill. It is shifting of pollution & its problem from liquid to the solid phase. The organic pollutants from industry are the source of energy and can be used as fuel. This research work collects the latest information on recent trends in the conversion of sludge to fuel as value-added products such as briquette, energy. The present studies are carried out on the sludge generated from the Sewage Treatment Plant. The sludge is dewatered by using different types of filtering mediums. The dewatered sludge is mixed with other ingredients to make the briquettes and energy. The briquettes are sundried to use as fuel for domestic and industrial use. The briquettes are analyzed for their fuel value. We have also studied the brief design aspects of the horizontal anaerobic batch bioreactor. The cost of the briquettes is also given. Thus this research work gives the most promising value-added usage for the sludge and helps to keep the environment green and sustainable with the energy conservation concept.

Study of indiscriminate distribution of restrained antimicrobial resistome of different environmental niches.

Prophylactic usage and high persistent nature of several antibiotics have put selective pressure on the native microbial population that led to the emergence, propagation, and persistence of antibiotic resistance in nature. The surveillance of antibiotic resistome pattern and identification of points of intervention throughout the different environmental habitats will help to break the flow of antibiotic resistance from environmental bacteria to human pathogens. The present study compares the occurrence, diversity, and abundance of ARGs in industrial sludge, wetland sludge, and sediment sample contaminated with pharmaceutical discharge. Metagenomes were mined for the presence of ARGs against the ResFinder 3.2 database using BLASTn program. Pharmaceutical sample (2.52%) showed high degree of ARG abundance and richness as compared with ETP sludge (2.28%) and wetland sludge samples (1.29%). The modern resistome pattern represented by critically important resistance genes against tetracycline (tetA, tetC, tetW, tetT, and tetS/M) and quinolone (qnrS, qnrVC, and qnrD) was identified in pharmaceutical sediment sample. However, effluent treatment plant (ETP) sludge sample showed abundance of multidrug efflux pumps indicating the presence of primitive resistome profile. In conclusion, the indiscriminate distribution pattern of antibiotic resistance genes in three selected environmental sites suggests enrichment and distribution of environmental niche-driven resistance. The study also suggests effluent discharge site from pharmaceutical industries and ETPs as pivotal points of intervention for the mitigation of antibiotic resistance.

Adsorption of ibuprofen, ketoprofen, and paracetamol onto activated carbon prepared from effluent treatment plant sludge of the beverage industry

The presence of emerging contaminants such as pharmaceuticals in aquatic means presents as a serious threat, since their real consequences for the environment and human health are not well known. Therefore, this work consisted of preparing and characterize sludge-derived activated carbons (beverage sludge activated carbon - BSAC and acid-treated beverage sludge activated carbon - ABSAC) to investigate their use in the pharmaceuticals adsorption in aqueous media. The morphology study has demonstrated that ABSAC, unlike BSAC, exhibited an abundant porous structure, with smaller particles and bigger roughness. Adsorption results indicated that the ABSAC was more effective that BSAC, since it presented superior surface area (642m2g-1) and total pore volume (0.485cm3g-1) values. Pseudo-second-order kinetic model was more suitable to predict experimental data. Sips model best described the equilibrium data, with maximum adsorption capacities of 145, 105, and 57mgg-1 for paracetamol, ibuprofen, and ketoprofen, respectively. Besides, the sludge-derived adsorbent was highly efficient in the treatment of a simulated drug effluent, removing 85.16% of the pharmaceutical compounds. Therefore, the material prepared in this work possesses intrinsic characteristics that make it a remarkable adsorbent to be applied in the treatment of pharmaceutical contaminants contained in industrial wastewater.

Heavy metals speciation study revealing merits of anaerobic co-disposal of municipal solid waste with discrete paper mill sludges: An experimental investigation in simulated landfill bioreactors

Speciation of heavy metals (Cu, Cr, Pb, Ni, Cd and Zn) during anaerobic co-disposal of two distinct paper mill sludges viz. effluent treatment plant sludge and de-inking plant sludge with municipal solid waste in anaerobic landfill bioreactor was investigated. Effects of moisture content, volatile solids and pH on fractionation of heavy metals over the course of landfilling were also analyzed. Study revealed enhancement in bioavailability of Cu, Cr, Ni and Cd on sole disposal municipal solid waste in bioreactor landfill over 300 days. However, co-disposal of effluent treatment plant sludge with municipal solid waste showed reduction in bioavailability of every analyzed heavy metals with maximum increment in stable residual forms of Cu, Cr, Pb, Ni and Zn by 3.70 %, 0.73 %, 3.08 %, 1.17 % and 3.45 % (dry weight), respectively. De-inking sludge co-disposal was also found effective for reducing bioavailability of Cu, Cd and Zn while bioavailability of Cr, Ni and Pb was unaltered. Strong correlations between increase in residual forms of heavy metals and volatile solid reduction obtained for both co-disposed bioreactors.

Chemically modified biochar derived from effluent treatment plant sludge of a distillery for the removal of an emerging pollutant, tetracycline, from aqueous solution

Distilleries are among the most pollution-generating industries as their ≈80% raw material converted into waste. In the present study, sustainable biochar was prepared from distillery sludge (DS) by chemical activation with KOH, ZnCl2, and H3PO4 (coded as DS-K, DS-Z, DS-H) and used for the removal of tetracycline, an emerging pollutant. Additionally, biochar was also prepared by adding the distillery sludge and oily sludge from sugar mill in the ratio of 2:1 (coded as DS-O). The raw sludge and prepared biochar were characterized by various sophisticated techniques like XRF, XRD, TGA-FTIR, BET, FE-SEM, and zeta potential analyzer. FTIR, coupled with the TGA system, gave traces of CO2 and H2O (steam) as the temperature of the sample increased. Batch adsorption study showed TC removal efficiencies of 57%, 64%, 43%, and 70% by DS-K, DS-Z, DS-H, and DS-O, respectively, at optimum conditions: Co = 20 mg L−1, time = 300 min, rpm = 160 ± 5, dose = 1 g L−1, T = 25 ±1 °C, and pH = 6. Experimental data was well-fitted in both pseudo-first-order and pseudo-second-order kinetic models. Langmuir isotherm nicely described the adsorption of TC onto biochar. pH played a significant role in the adsorption due to the amphoteric behavior of TC. Reusability studies showed a marginal decrease in removal efficiencies of ≈ 9%, ≈ 7%, ≈ 4%, and ≈ 8% after three consecutive runs with DS-O, DS-Z, DS-K, and DS-H, respectively.

Experimental study on concrete by partial replacement of fine aggregate by textile effluent treatment plant sludge

Chemical sludge produced by textile industries poses a high threat to the environment causing pollution in all stages of its treatment and disposal. In this study sludge from textile dying unit was collected. It has been partially replaced for fine aggregate in concrete up to 20% replacement to find out the possibility of reuse of this hazardous waste in build materials. Manufactured sand made by grinding angular aggregates was used as fine aggregate. Study shows that the samples failed to meet the desired compressive strength required for structural applications. The reason for failure in strength development is to be further experimented by individual analysis of sludge components.