Effluent Treatment

Waste water samples from sugar industry were collected and analyzed for biological oxygen demand (BOD) and chemical oxygen demand (COD). In the present study, Mangifera indica leaf powder was used for the treatment of sugar mill effluent. The kinetics of COD and BOD degradation were measured and fitted to several equations (zero-, first-, second-, diffusion, parabolic diffusion, simple Elovich and exponential equations). Two initial COD and BOD concentrations were 21216 mg/l and 9333 mg/l respectively and the observations were carried out for 8 hours. Even though zero-, second-, parabolic diffusion and exponential kinetics adequately describe the data, diffusion kinetics indicated the best model for describing the degradation of organic matter with high coefficient of determination (R 2 = 0.928 and 0.937 respectively for COD and BOD reduction). The data indicate that the prepared adsorbent surface sites are heterogeneous in nature and that fits into a heterogeneous sitebinding model. Commonly used isotherms namely Freundlich and Temkin models were studied. The present system followed the Temkin isotherm model. The results supported that the Mangifera indica based bioadsorbent can be used to remove the excess organic waste from its contaminant sources.

This study investigates the effectiveness of wastewater treatment systems within Bangladesh’s textile sector, focusing on two facilities at Ishwardi Export Processing Zone: a central water treatment plant (WTP) supplying factory process water and an onsite effluent treatment plant (ETP) at Vintage Denim Studio Ltd. Through systematic field measurements, we evaluated raw and treated water quality parameters—including total dissolved solids (TDS), salinity, electrical conductivity (EC), and temperature—alongside noise and particulate emissions. GPS logging ensured precise sampling locations, while series testers and particulate counters provided real-time data on water chemistry and air quality. Wastewater flow rates, treatment capacity, and compliance with national discharge standards were assessed, and worker perceptions of health, safety, and operational practices were collected via structured surveys. Data analysis using Excel and ArcGIS Pro revealed that both treatment systems maintain overall water chemistry within narrow operational ranges, with slight variations in TDS and salinity and stable EC readings, highlighting balanced ionic control. Biological treatment at the ETP demonstrated consistent performance, producing an effluent quality well suited for downstream filtration stages. However, survey findings indicated opportunities to strengthen health and safety protocols, increase renewable energy use, and enhance wastewater reuse. The study’s multi-dimensional approach underscores the need for ongoing process optimization, integrated management strategies, and policy support to achieve sustainable water use and environmental protection in Bangladesh’s textile industry.

This study explores pollutant behaviour in water and soil environments, specifically focusing on unsaturated soil zones where vertical moisture and contaminant migration predominate. Soil column experiments used undisturbed soil cores from Mangaluru's coastal sites. A constant-level tank stored seawater and distilled water, introduced from the top, with filtrate collected at the base. Both soil and water samples underwent a comprehensive parameter analysis preand post-experiments. The morphology, elemental composition, and mineralogical structure of the collected soil samples were evaluated using scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. In addition to that, basic soil tests were also performed. The results show that when seawater traversed the undisturbed soil columns, there were reductions in the concentrations of EC, TDS, alkalinity, chlorides, and potassium, alongside an increase in the concentrations of hardness, BOD, and COD. Similarly, when distilled water flowed through the columns, there was an increase in the concentrations of all the parameters. In the realm of soil composition, the introduction of seawater led to declines in the concentrations of available P 2 O 5 , calcium, magnesium, zinc, iron, and manganese. In contrast, the passage of distilled water resulted in reductions in EC, available P 2 O 5 , K 2 O, sulphur, calcium, magnesium, zinc, iron, boron and manganese concentrations. These soil analysis findings were congruent with the outcomes of the water analysis, affirming the migration of pollutants from the soil to the water medium. Overall, this study underscores the pivotal role played by soil properties in solute transport and the potential for the movement of pollutants between soil and water environments.

The combinations of H 2 O 2 /Fe +2 , UV/H 2 O 2 /Fe +2 and UV/H 2 O 2 process were investigated on treatment of oil recovery industry wastewater. Treatment of oil recovery industry wastewater, a typical high pollution strength industrial wastewater (chemical oxygen deman (COD): mg l -1 , biological oxygen demand (BOD): 8000 mg l -1 , oil and grease:1140 mg l -1 , total dissolved solids (TDS): 37000 mg l -1 , total suspended solids: 2580 mg l -1 ), was carried out by batch oxidation processes. The optimal mass ratio for H 2 O 2 /Fe +2 yielding the highest COD removal was found to be 8.658 corresponding to 200.52 g 1 -1 H 2 O 2 and 23.16 g l -1 Fe +2 concentrations for 60 minutes reaction time. Fenton process gave a maximum COD reduction of 86% (from 21000 to mg l -1 ) and the combination of UV/H 2 O 2 gave a COD reduction of 39% (from 21000 to 12730). The percentage of removal, after the total reaction time (3.5h), H 2 O 2 : 8.4 g l -1 and Fe +2 : 0.05g l -1 , in the photo Fenton process, corresponded to 81 % of the total initial COD (4200 mg l -1 ). The oxidative ability of the UV/Fe +2 /H 2 O 2 process (81%) was greater than that of the UV/H 2 O process (55%) for 80% diluted wastewater. COD removal efficiency for UV/H 2 O 2 process (COD/H 2 O 2 =1/2 (w/w)) was 90%, 55%, and 39 when initial COD was 1050, 4200, and mg l -1 , respectively, whereas COD removal was 943, 2320, and 8270 mg l -1 , respectively.

Polysiloxanes are characterized by silicon and oxygen backbone and are hydrophobic in nature with low moisture uptake widely used for medical applications. Polysiloxane immobilized thiosalicylic acid ligand system has been prepared through sol-gel method, gelation was observed after 40 minutes. The immobilized ligand was characterized using FTIR, the spectrum showed characteristic absorption bands (cm-1) at: 3377 (OH), 2981 (C-H stretch); 2631 (SH); 1587 to 1684 (C=C, C=O); 1032 to 1144 (Si - O) respectively. SEM analysis showed irregular particle sizes of the polysiloxane matrices while EDX elemental composition gave (wt %): 3-CPPS; Si (50.45), O (25.02) and Cl (24.57). F - 3CPPS showed, O (58.68), Si (41.32); thiosalicylic (7.14 of S). The extraction of metal ions (Cr3+, Fe3+, Pb2+, Cu2+ and Zn2+) were studied using Microwave Plasma Atomic Emission Spectrophotometer (Agilent MPAES-4200) at pH 6.0. Thermodynamic range with respect to Cr3+, Fe3+, Pb2+, Cu2+ and Zn2+ yielded negative...

The batch adsorption experiment was carried out for the removal of dye by using the leather waste from the leather industry as an adsorbent. The efficiency of the adsorbent was studied by varying the parameters contact time, initial concentration, adsorbent dose, pH and Temperatures. The isotherm was studied by shaking 250 mg of adsorbent in 50 ml of dye solution of concentration range of 50-125 mg/l. The equilibrium was achieved after 180 minutes for this study. The experimental equilibrium data for this system has been analyzed using the linearized forms of Langmuir and Freundlich isotherms. The Langmuir isotherm was found to provide the best theoretical correlation of the experimental data. The maximum capacity of adsorbent was determined by analyzing the experimental equilibrium data. This study showing the utilization of solid waste to treat the liquid waste and also satisfying the applicability and suitability of this adsorbent for dye containing wastewater treatment.

Granite cutting plant is one such industry that releases polluting and turbid effluent. The residue from all these processes is discharged with water as an effluent. The effluent mainly contains many solids that harm the environment. Hence it requires treatment techniques before disposal. Several conventional methods are available for removal of contaminants like coagulation, adsorption, polyelectrolyte methods and biological methods. Most of them are cost prohibitive. The reduction of solids concentration in the effluent before disposal by using the techniques, coagulation followed by adsorption using natural adsorbents, like rice husk carbon and saw dust carbon, in contrast to the usage of activated carbon as it is costly. From a local Granite cutting plant near Anantapur, the effluent is collected and its physico-chemical characteristics are estimated and found to be pH(7.5), TS(4240mg/l), TSS(21560mg/l), TDS(12373mg/l).Effluent obtained is subjected to coagulation by potash alum followed by adsorption using saw dust carbon and rice husk carbon. Percentage removal of solids for a contact time of 40 minutes and adsorbent dosage of 0.1g/ml is maintained. The percentage removal of solids based on time variation are TSS=50%, TDS=57% for rice husk carbon; TSS=62%, TDS=60% for saw dust carbon. Percentage removal of solids for a contact time of 25 minutes and adsorbent dosage of 0.25g/ml, the percentage removal of solids based on concentration variation are TSS=68%, TDS=50% for rice husk carbon; TSS=72%, TDS=52% for saw dust carbon. A comparison of the characteristics of effluent treated by rice husk carbon and saw dust carbon revealed that saw dust carbon ensured better removal of solids. However no variation in pH is observed.

Dedico este trabalho à minha família. A meus filhos Thiago e Mariana, que entenderam e aceitaram tantos momentos de ausência e a entrada efêmera de um novo membro na família. A turfa... À minha esposa Adair, companheira fiel, cúmplice dos meus sonhos. iv AGRADECIMENTOS Agradeço a todas as pessoas que contribuíram, de uma forma ou de outra, à realização deste trabalho. Amigos e colegas do curso de Pós Graduação, pelas discussões e apoio. Aos funcionários do instituto, pelo cuidado e carinho no atendimento àquilo que necessitei. Esquivo-me de tentar nomeá-los pois não seria tarefa simples e algum eventual esquecimento seria imperdoável. Quero agradecer, em particular, ao Prof. Dr. Joel Barbujiani Sígolo, orientador deste trabalho. Certo que nele encontraria a melhor orientação, propus-lhe o tema com a promessa de não representar muito trabalho à sua já atribulada vida acadêmica. Felizmente ele engoliu... Agradeço a meu "irmãozinho" Serginho Petroni, que me ajudou a desvendar muitos dos mistérios químicos das turfas. Agradeço à FAPESP que financiou na íntegra esta pesquisa (Proc. 00/07512-7) Agradeço ao Instituto de Geociências da Universidade de São Paulo novamente acolher uma ovelha desgarrada há mais de 20 anos... Obrigado a todos. v SUMÁRIO 1 INTRODUÇÃO.

Dedico este trabalho à minha família. A meus filhos Thiago e Mariana, que entenderam e aceitaram tantos momentos de ausência e a entrada efêmera de um novo membro na família. A turfa... À minha esposa Adair, companheira fiel, cúmplice dos meus sonhos. iv AGRADECIMENTOS Agradeço a todas as pessoas que contribuíram, de uma forma ou de outra, à realização deste trabalho. Amigos e colegas do curso de Pós Graduação, pelas discussões e apoio. Aos funcionários do instituto, pelo cuidado e carinho no atendimento àquilo que necessitei. Esquivo-me de tentar nomeá-los pois não seria tarefa simples e algum eventual esquecimento seria imperdoável. Quero agradecer, em particular, ao Prof. Dr. Joel Barbujiani Sígolo, orientador deste trabalho. Certo que nele encontraria a melhor orientação, propus-lhe o tema com a promessa de não representar muito trabalho à sua já atribulada vida acadêmica. Felizmente ele engoliu... Agradeço a meu "irmãozinho" Serginho Petroni, que me ajudou a desvendar muitos dos mistérios químicos das turfas. Agradeço à FAPESP que financiou na íntegra esta pesquisa (Proc. 00/07512-7) Agradeço ao Instituto de Geociências da Universidade de São Paulo novamente acolher uma ovelha desgarrada há mais de 20 anos... Obrigado a todos. v SUMÁRIO 1 INTRODUÇÃO.

BACKGROUND: Nitrogen doped titanium dioxide (N-TiO 2), iron doped titanium dioxide (Fe-TiO 2), and undoped titanium dioxide (TiO 2) nanocatalysts were synthesized using sol-gel method aided with ultrasound (US). The effects of duty cycle, US-power, and US irradiation time on catalyst characteristics were investigated so as to establish the best synthesis conditions. RESULTS: The optimum parameters for minimum mean size of catalyst particles were 60% duty cycle, 100 W power, and 20 min as irradiation time. X-Ray diffraction (XRD) analysis revealed that the primary phase of all nanocatalysts was anatase with crystallite size as 46.29 nm, 54.32 nm, and 56.17 nm for N-TiO 2 , Fe-TiO 2 , and undoped TiO 2 , respectively. Field electron scanning electron microscopy (FE-SEM) images confirmed that N-TiO 2 is a mixture of TiO 2 microspheres and rice-like structures whereas Fe-TiO 2 and undoped TiO 2 were spherical. X-ray photoelectron spectroscopy (XPS) study showed that both N-TiO 2 and Fe-TiO 2 exhibited minor shifts to lower binding energies when compared to the spectra of undoped TiO 2. The application studies for obtained catalysts using simple ultrasonic horn and disc horn coupled with oxidants revealed best results (51.67% reduction in COD) using disc horn for N-TiO 2 catalyst obtained using ultrasound at pH of 12 and addition of a 20 mL per L-1 dose of H 2 O 2. CONCLUSION: Doping TiO 2 with metal and non-metal ions coupled with using ultrasound in synthesis improved the catalytic activity with maximum COD reduction of commercial effluent obtained for disk horn + N-TiO 2 + H 2 O 2 based approach.

A fixação de nitrogênio para a produção de amônia é uma das reações químicas mais importantes atualmente, devido à utilização de amônia na produção de fertilizantes que auxiliam na manutenção da cadeia alimentícia para a sociedade. Com o objetivo de promover a fotofixação de nitrogênio, neste trabalho foram desenvolvidos nanopartículas bimetálicas de FeNi, NiCo, FeMo e RuPd suportadas (1% em massa de metal) na superfície de nitreto de carbono (C3N4) para serem testados como sistemas catalíticos. Os resultados mostram que o melhor desempenho foi obtido através do catalisador RuPd/C3N4 (RuPd NPs: 4,6 ± 1,1 nm) para a fotofixação de nitrogênio em água a 25 ºC utilizando etanol (10% m/m) como agente de sacrifício. As taxas de produção de amônia, expressas em termos do NH4+ formado, atingiram até 1389,84 mol.g-1.h-1 e o rendimento quântico aparente foi de 6% para a reação catalisada pelo material RuPd/C3N4, que foi muito superior aos valores observados para os sistemas monometálicos e os...

Objective: This study investigates the application of bioreactor technology for sustainable waste management in food testing laboratories. This research explores how organic lab waste can be converted into bioenergy and reusable materials by analyzing different bioreactor configurations, including anaerobic digesters and microbial fuel cells. Study Design: A detailed review of existing literature, case studies, and industry reports between 2018 and 2025 was carried out to assess the recent trends and impact in the adoption of bioreactors systems. Methodology: The research draws from peer-reviewed journal articles, government reports, and Food industry analyses. It follows a qualitative review approach, including data visualization to highlight the need, use and impact of sustainable systems such as bioreactors. Results: Findings indicate that integrating bioreactors into laboratory waste management systems reduces environmental impact and offers a cost-effective solution for food safety laboratories. This research provides a framework for adopting sustainable practices in food quality assurance facilities, contributing to the circular economy and environmental conservation efforts.

Con el muestreo de sedimentos de corriente en la cuenca del río Torres-Vizcarra (Huánuco-Ancash), los que han sido sometidos al método de especiación química, se ha podido caracterizar el proceso de dispersión de los principales elementos metálicos. Dicha caracterización se lleva a cabo al relacionar el contenido total del metal y el contenido residual en una muestra, obteniéndose el factor denominado dispersión relativa, el cual se ha podido determinar para los principales elementos, destacando el cobre, plomo, zinc y cadmio por su muy alta movilidad, en tanto que en el cromo y vanadio es baja. La aplicación de la técnica de extracción secuencial, así como permite definir las fracciones de los elementos metálicos que se movilizan en un ambiente dado, identificando las fracciones biodisponibles, permite también identificar el real impacto ambiental producto de la dispersión de metales pesados en sedimentos.

This article focused on the application of activated carbon produced from dry bamboo for the removal of pollutants from paint based waste water. Wastewater samples were collected from paint making industry in Awka, Anambra State and subjected to treatment using activated carbon produced from waste dry bamboo by adsorption and filtration method. The raw wastewater and the treated water were tested for physicochemical parameters using the ASTM testing methods. The results showed evidence of the presence of heavy metals (lead, mercury, chromium, copper, etc), oil and grease as well as dissolved oxygen and biochemical oxygen demand. The concentration of pollutants in the raw and treated waste water were pH: 7.

The efficiency of snail shells as adsorbent for treating wastewater from PEMO Food Industry in Edo State was investigated. Treatment was achieved by adsorption of contaminants in wastewater onto snail shell powder. Physicochemical analysis of the treated wastewater was conducted at intervals of 10 minutes for a total treatment time of 120 minutes. Water quality parameters such as pH, Conductivity, BOD, COD, DO, TSS, TDS, TS, Alkalinity, Turbidity, Temperature, Nitrate, Sulphate, Phosphate, Lead, and Cadmium were measured to determine the efficiency of snail shell adsorbent. The statistically observed significant difference at 95% confidence limit (P≤0.05) for the treatment data indicates the effectiveness of the adsorbent and supports the high efficacy of snail shell in the treatment. Kinetics analysis was carried out by evaluating the timedependence of the different quality parameters after treatment using Pseudo-First order, Pseudo-Second order, and Intra-particle diffusion models respectively. The results show that the treatment fits Pseudo-Second order kinetics when compared to Pseudo-First order and Intra-particle diffusion model since R 2 values of the parameters showed excellent linearity towards unity (R 2 ≥0.99); except for TSS and Pb which showed deviation from linearity when compared to the other models. Treating wastewater for TSS and Pb followed Intra-particle diffusion kinetics (R 2 ≥ 0.9). The results of this study demonstrate the efficacy of snail shells as a cost-effective adsorbent and green remediation material in treating wastewater from the food industry, with the observed kinetics providing insightful information and knowledge in understanding the adsorption mechanism of wastewater treatment using snail shells as bio-adsorbent.

Senhor, concedei-me capacidade de aceitar as coisas que não posso mudar, coragem para transformar aquilo que posso e sabedoria para saber a diferença entre ambas." R. Niebuhr v Agradecimentos Ao departamento de Engenharia Química da Universidade Federal do Rio Grande do Sul, seus professores e funcionários, pela colaboração técnica e fornecimento das condições técnicas para o desenvolvimento deste trabalho. Aos professores Marla e Celso pela amizade, confiança, carinho, competência, dedicação e orientação deste trabalho. Aos colegas e amigos do Departamento de Engenharia Química pela amizade e companheirismo, principalmente aqueles que demonstraram serem grandes e verdadeiros amigos. À minha família pelo amor, carinho, atenção e apoio nos momentos mais difíceis. Às colegas do LARET, Melissa, Fernanda e Juliana, não só pela colaboração prestada no decorrer da pesquisa, bem como, pela atenção, amizade e companheirismo. Aos funcionários, Sirley e Fernando, agradeço pelos inúmeros momentos em que me ajudaram durante o trabalho experimental. À CAPES, pela concessão da bolsa de mestrado. vi Nesse trabalho foi avaliada a reação de degradação fotocatalítica do estireno em solução aquosa, usando TiO 2 (P-25, Degussa) como catalisador. Os experimentos foram realizados em um reator batelada de vidro, com controle de temperatura e catalisador em suspensão. Como fonte de radiação foi usada uma lâmpada de luz UV de 28 W. A determinação das concentrações de estireno foi feita por cromatografia gasosa com detector de ionização de chama (FID). Preliminarmente foram realizados testes para determinar o tempo de contato necessário para atingir o equilíbrio de adsorção. Além disso, visando separar a fotólise da fotocatálise, foram realizados experimentos nos quais a solução foi irradiada com e sem TiO 2 e, também, na presença de TiO 2 , mas sem irradiação. Na seqüência foram avaliadas as influências da concentração inicial de estireno, da concentração de catalisador, da adição de peróxido de hidrogênio e do pH inicial da solução. Os resultados experimentais mostraram que o estireno pode ser degradado por fotocatálise e que, com 90 min de irradiação, na presença de TiO 2 , a degradação fotocatalítica é de 95,0%, sendo atingindo o limite de detecção em 180 min. Constatou-se que a taxa de degradação do estireno pode ser aproximada por uma cinética de pseudoprimeira ordem para concentrações iniciais de estireno entre 15,3 e 57,2 mg L -1 , na temperatura de 30°C. Observou-se, ainda, que a adição de H 2 O 2 acelera a reação de degradação até que se alcance uma determinada concentração do peróxido na mistura reacional, chamada de ótima. Concentrações maiores que a ótima, resultam em redução da taxa de reação. Além disso, foi detectado um produto da degradação do estireno, o benzaldeido. Para este composto foram realizados experimentos de adsorção e, na seqüência, foram avaliadas as influências da concentração inicial e do pH inicial da solução. A cinética de degradação do benzaldeído segue o modelo de Langmuir-Hinshelwood, não podendo ser empregada uma cinética de pseudoprimeira ordem, na faixa de concentrações estudada. Foi realizado, também, um balanço molar para o carbono, com base nos resultados experimentais de concentração de estireno, concentração de benzaldeido e carbono orgânico total. Este balanço indicou que existe na mistura reacional pelo menos um composto orgânico desconhecido, cuja presença é significativa a partir dos 90 min de reação. Ignorando-se este(s) composto(s), foi proposto um modelo cinético que é válido para os primeiros 30 min de reação. A partir deste tempo, há uma diferença significativa entre os resultados experimentais e os calculados.

This study investigates the evolution of the biofilm matrix responsible for treating effluent from a pulp mill and identifies the microbial community by 16S rRNA gene sequencing. In addition, a biocarrier promising a functional structure with better specific features for biofilm formation than traditional polyurethane carriers was explored. The average removal efficiencies were 43.7% for chemical oxygen demand (COD) and 62.7% for biochemical oxygen demand (BOD5). The color increased during the treatment, indicating anoxic zones being formed in the inner part of this type of carrier. Periodic micrographs showed the evolution of extracellular polymeric substances and materials like fungi and bacteria adhered to the carriers. Genetic sequencing confirmed the presence of Bacillus sp. and Paenibacillus glucanolyticus, species with the potential to degrade and discolor pulp industrial effluents. Results offer a potential basis to enhance treatment facilities of pulp and paper mills based on microbial activities.

The conventional electrode aluminum used in electrocoagulation (EC) for the textile wastewater undergoes pitting type of corrosion, so dissolution of the same is very high during electrolysis. This research focuses on the treatment of real-time textile effluent with copper electrodes that corrode uniformly during electrolysis, with optimizing operating parameters for high color removal efficiency (CRE%). The sludge acquired was analyzed by XPS and XRD to study the mechanism of dye removal. The treated effluent was subjected to phytotoxicity analysis using Vigna radiata to study the toxicity effect of the intermediary products. 98.6% of CRE was attained in treating the effluent with copper electrodes. XPS and XRD results showed that both Cu(OH) 2 and CuO served as coagulants in the dye removal. The phytotoxicity results showed that the percentage of germination, shoot and root lengths of Vigna radiata in the treated effluent were similar to the results obtained for the control.

Unplanned occupations have been a growing concern in urban areas, causing negative impacts on the environment and public health. The aim of this study was to investigate the damage caused by the occupation of allotments located near water bodies in an area of the municipality of Peruíbe without sewage systems. A review of the literature and applicable legislation covered concepts related to unplanned occupations and their environmental impacts, as well as a case study on monitoring water bodies. The research methodology included field data collection and qualitative and quantitative analysis of the data obtained. The contributions of this study include the identification of the main impacts of these occupations, an analysis of the legislation on the classification of water bodies, as well as proposing possible mitigation measures and good practices for the proper management of these occupations. The results indicate that the water bodies in the region studied present critical problems in terms of physical, chemical and biological aspects compared to the standards established in current legislation. This discussion could help formulate more effective public policies to protect water bodies and promote sustainable urban development in the municipality of Peruíbe.

The present study was conducted to explore the efficiency of water hyacinth (Eichhornia crassipes) to cleanup of tannery effluent in terms of pH, TDS, EC, BOD and most importantly Cr. The study period was from November, 2013 to April, 2014. After 7 days of treatment by water hyacinth, the removal rates were: 68.15% for BOD, 59.82% for TDS and 46.56% for EC, where the corresponding rates after 15 days were: 81.73% for BOD, 67.15% for TDS and 61.93% for EC. After treatment with water hyacinth, pH of effluent reached to nearly neutral level from alkaline condition. In this study, major focus was on Cr removal and the treatment of tannery effluent using water hyacinth resulted in 32.42% reduction of Cr after 7 days and 54.72% after 15 days. The present results revealed that water hyacinth had the strong capability of absorbing Cr. On the other hand, the reduction rates after 15 days for sedimentation were: 54.23% for BOD, 30.21% for TDS, 22.28% for EC and 14.37% for Cr. After comparing ...

Industrial pollution has been and continues to be a major threat to the environment affecting the water we use, the air we breathe and the soil we live on. Among the various industries, sugar mill is one of the largest and most important agro based industries in India. In this study, the content of heavy metals in the sugar mill effluent samples were analysed quantitatively. The presence of heavy metals like arsenic, cadmium, copper, lead, mercury, zinc, chromium was detected in all the samples analyzed.

Soil column experiment was conducted in the laboratory to find out the effect of spentwash application on leaching of salts to assess the downward movement of spentwash on groundwater quality. The treatment comprised of different doses of spentwash at the rate of 0, 25, 50 and 100 m ha. The treatments were applied uniformly and mixed thoroughly in the top 10 cm of the column. The soil was left for incubation for 15 days and thereafter leaching with distilled water, the leachate samples were analyzed for various parameters like pH, EC, cations and anions at periodical intervals. The results revealed that increasing dose of spentwash application increased the pH and reduction in the EC of the leachates over the period of leaching events. Among the cations, K , Na, Ca and Mg were higher in the leachates upto 4 leaching events and thereby decreased, similar trend of results were noticed in the anions. The soil collected after 8 leaching event contained appreciable amounts of all the ion...

The activated sludge process simply involves bringing together wastewater and a mixed culture of microorganisms under aerobic conditions. The system usually includes a secondary treatment given to the settled sewage, and requires an environment in which active microorganisms are maintained in intimate contact with wastewater in the presence of sufficient oxygen. In this study, the treatment of industrial effluents, by using laboratory activated sludge unit was investigated. The reduction of the pollution laws was determined, using the biochemical oxygen demand (BOD) and the chemical oxygen demand (COD) methods. The results indicated that the pollution laws was reduced by up to 98% in the activated sludge unit.

The present work deals with the study of physico-chemical parameters of industrial effluents of five pharmaceutical industries entering into common effluent treatment plant (CETP). The study reveals that the effluents from pharmaceutical industries in Baddi (H.P.) has changed the water quality of the Sarsa River in which effluent has been discharged after treatment. Besides other industries in the surrounding, pharmaceutical industries are also responsible for polluting the aquatic environment. During these investigations, It has been observed that temperature in the effluents of all the industries ranged from 24 C to 26 C; pH values of pharmaceutical Industries were in the limit of 1.63 to 8.57; Pharmaceutical Industry 1 has shown drastic decrease in pH level. Alkalinity was found to range between 700-1100 mg/l in all the effleunt samples. Pharmaceutical Industry 1& 5 have shown alarming level of total hardness. These results highlight that the discharge of highly polluted effluent...

Wastewater from leather processing industries is very complex and leads to water pollution if discharged before treatment, especially due to its high organic loading and chromium content. Over the past years, Nakuru Tanners Ltd has been discharging raw effluents into the Ndarugo River causing pollution of surface waters, groundwater and soil. Since the water from this river is used for drinking, agricultural and industrial purposes, the assessment of the effluents is necessary. A study to determine the level of toxicants in Nakuru tannery wastewater discharged to the environment was undertaken. Water samples from four sampling points (S1 – Pre-tanning Stage, S2 – Tanning Stage, S3 – Post-tanning Stage and S4 – Drainage to the river) were collected and analyzed. A comprehensive experimental evaluation of tannery wastewater was performed as a basis for the determination of the levels of different pollutants , BOD, COD, pH, turbidity, TSS, NO3- and NO2- and the values obtained were com...

Aquatic plants, including duckweed (Lemna minor), are
increasingly utilized in sewage and wastewater treat-ment to
improve pollution parameters and organic matter removal.
This study aimed to investigate the impacts and efficacy
of duckweed in secondary clarifier tanks in a conventional
biological treatment facility. The per-formance of four
secondary clarifiers with and without duckweed was compared
based on water quality efflu-ent and settling characteristics.
As per the experiment results, the secondary clarifier tank
with duckweed demonstrated higher removal efficiency for
chemical oxygen demand (COD), biological oxygen demand
(BOD5), ammonium, phosphate, total nitrogen (TN), and
total phosphorus (TP) – of 70%, 75%, 72%, 82%, 67%, and 96%,
respectively, compared to the tank without duckweed. The
concentration of suspended solids in the effluent and sludge
volume index (SVI) values were similar in both settings. The
research findings suggest that duckweed can contribute to
the treatment efficiency of conventional biological treatment
plants, thus re-ducing the need for tertiary nutrient removal.
Additionally, the cost-effectiveness of treatment with
duckweed and its reuse as fertilizer and animal fodder make it
a valuable resource. The optimal temperature for duck-weed
growth is approx. +26°C, and it is influenced by sunlight and
temperature more than nutrient concentra-tions.

This research aims to investigate the effects of fermented diets on the productivity of M. macrocopa. The fermented soybean powder (FSBP) and fermented corn powder (FCP) were prepared based on liquid fermentation using Bacillus subtilis at 40 ºC and 60 ºC, and for 12h and 48h, respectively. A total of 9 dietary treatments (baker’s yeast Saccharomyces cerevisiae as control; FSBP-40ºC-12h, FSBP-40ºC-48h, FSBP-60ºC-12h, FSBP-60ºC-48h, FCP-40ºC-12h, FCP-40ºC-48h, FCP-60ºC-12h, FCP-60ºC-48h) were used for M. macrocopa cultures (n=4) initiated with 8 neonates per liter. After 14 day of cultivation, the population growth rate, population composition (numbers of neonate, asexual female and sexual female), ratio of asexual to sexual females and size of the females were evaluated. The results indicate that the fermented diets affected differently the production of M. macrocopa. Among the FSBP treatments, the highest population growth rate was found in the FSBP-60ºC-48H treatment (74.67 ± 26.18 ind./ day), while the lowest population growth rate was measured in FSBP-40ºC-12H treatment (0.11 ± 0.15ind./day). Among the FCP treatments, the significantly-highest population growth rate (43.26 ± 6.60 ind./ day) was found in the FCP-40ºC-48H treatment, while the significantly-lowest population growth rate was revealed in the control treatment (12.24 ± 4.1 ind./day). The results of population composition indicate that the FSBP-60ºC-48H diet is the optimal diet to increase the neonate production and ratio of asexual female/sexual female of M. macrocopa. On the other hand, the body size of FCP-fed M. macrocopa were globally larger than the FSBP-fed cultures. These tentative results suggest that Bacillus-fermented soybean and corn powders could improve the productivity of M. macrocopa, and provide implications for their mass production. Future research should focus on exploring the impacts of fermented diets on the nutritional value of M. macrocopa, and their further application in fish larviculture.

The present paper makes reference to the study of the technical parameters of the tailing from Ticapampa and its application for the filling in paste. For this case, it has been considered as a typical case, the tailing from Ticapampa, which it is the most representative and important because its several composition. As it is well know, the paste is a mixing of water with solids of high density which contains a lot of fine particles with a lower water content, which is controlled by the Abrahams Cone. The main purpose of this study is based in the establishment of the technical parameters of the properties of the filling paste derived from the tailing which is used as a material of hydraulic filling in the underground mining works such as the main galleries, the mining shafts and chopping blocks and others that require support and protection to the geologic environment surrounded of the future sinking and fails caused for these mining works.

As ferritas são uma classe de materiais de fórmula molecular MFe2O4, em que M representa um cátion de um metal bivalente, tal como: cobre, zinco, cobalto, níquel, entre outros. São considerados óxidos mistos com uma composição molar de 70% de óxido de ferro e 30% de um óxido de um cátion bivalente[1]. As ferritas possuem propriedades magnéticas e estabilidade química e térmica, com propriedades para serem utilizadas como adsorventes de metais pesados [2], no tratamento de câncer por hipertermia [3], como absorvedores de microondas ou como blindagem contra interferência eletromagnética [4], na fotocatálise excitada pela luz visível [5,6], entre outras aplicações. Estes óxidos são considerados materiais cerâmicos magnéticos e possuem normalmente estrutura cristalina do tipo espinélio, podendo ainda conter estruturas do tipo granada, hexaferritas, dentre outras [7]

In this study, suspension of Escherichia coli ATCC 25922, Bacillus cereus NRRL 3711 and Staphylococcus aureus ATCC 25923 were exposed to microwave. The degrees of inactivation by the various time, initial bacterial cells amount and different power of microwave were compared systematically. Maximum efficiency of microwave was observed at 60 sec exposure time, 1.0 x 108 initial bacterial cells, and full power (900 W) for E. coli cells. Experimental data shows that microwaves apparently produced lethal effects on the ...

This work investigated the efficiency of polyethylene terephthalate (PET) as support material for TiO2 films in the photocatalytic degradation of red Bordeaux and yellow tartrazine dyes. The optimum operating conditions were determined by a factorial design, which resulted after 180 min of treatment in degradations of 99.5% and 99.1% for the UVC/H2O2/TiO2Sup and solar/H2O2/TiO2Sup systems, respectively. For the kinetic study, the experimental data fitted to the pseudo-first-order model and the calculated kinetic constants (k) values were 0.03 min−1 for the UVC/H2O2/TiO2Sup system and 0.0213 min−1 for the system solar/H2O2/TiO2Sup. It was verified that TiO2 supported in the PET remained with high degradation efficiency even after five cycles of reuse, indicating a good stability of the photocatalyst in the support. A significant reduction of TOC content was also observed along the reaction time. The phytotoxicity bioassay with Lactuca sativa demonstrated that after treatment with UVC...

Aquatic plants, including duckweed (Lemna minor), are increasingly utilized in sewage and wastewater treatment to improve pollution parameters and organic matter removal. This study aimed to investigate the impacts and efficacy of duckweed in secondary clarifier tanks in a conventional biological treatment facility. The performance of four secondary clarifiers with and without duckweed was compared based on water quality effluent and settling characteristics. As per the experiment results, the secondary clarifier tank with duckweed demonstrated higher removal efficiency for chemical oxygen demand (COD), biological oxygen demand (BOD5), ammonium, phosphate, total nitrogen (TN), and total phosphorus (TP)-of 70%, 75%, 72%, 82%, 67%, and 96%, respectively, compared to the tank without duckweed. The concentration of suspended solids in the effluent and sludge volume index (SVI) values were similar in both settings. The research findings suggest that duckweed can contribute to the treatment efficiency of conventional biological treatment plants, thus reducing the need for tertiary nutrient removal. Additionally, the cost-effectiveness of treatment with duckweed and its reuse as fertilizer and animal fodder make it a valuable resource. The optimal temperature for duck-weed growth is approx. +26°C, and it is influenced by sunlight and temperature more than nutrient concentrations .

In this study the wastes both solid and liquid from the various stage in the production of wet blue from wet salted goatskin were observed. Then the various types of parameter related to the environmental pollution during this production was determined. The parameters are pH, color, odour, solid wastes, total solids, suspended solids, dissolved solids, total acidity, free mineral acidity, strong alkali, total Kjeldahl nitrogen, sulphates, sulphides, chlorides, chromium, basicity, BOD, COD etc. In case of pH of soaking effluent is closer to the standard value but during liming and pickling or chrome tanning they exceed the limit. More interestingly, bad odour and colour to the receiving effluents are the common pollution. Surprisingly, suspended solid in soak liquor is much higher than that of other liquors. Additionally, the BOD and COD values of different effluents are extremely higher than tolerable limit causing a great threat to our environment. The results show that every param...

Avaliar a segregação, tratamento e destino dos resíduos radiológicos dado pelos cirurgiõesdentistas de Pelotas que possuem aparelhos de raios-X em uso no consultório odontológico e cadastrados na Vigilância Sanitária; e analisar o conhecimento dos mesmos acerca de sustentabilidade. Materiais e Métodos: Quarenta cirurgiões-dentistas de Pelotas-RS responderam um formulário contendo 16 perguntas que abordaram o conhecimento destes profissionais sobre a sustentabilidade, separação dos componentes sólidos do filme radiográfico, tratamento das soluções processadoras no consultório, destino final dos resíduos e uso correto do gerenciamento como ferramenta de marketing. Resultados: Verificou-se que 35,0% da amostra relatou lançar o revelador e o fixador em esgoto comum sem antes neutralizá-los. A maioria dos participantes (67,5%) afirmou acreditar no potencial poluidor da água de lavagem do filme durante o seu processamento, embora 65,0% deles relataram descartar o material diretamente em esgoto comum. Com relação à segregação dos resíduos sólidos, 37,5% dos dentistas disseram não separar os componentes do filme radiográfico. A maior parte deles (90,0%) afirmou ter conhecimento sobre desenvolvimento sustentável, 95,0% tentavam preservar o meio ambiente quando descartavam os resíduos do seu consultório e 70,0% acreditavam que a destinação apropriada dos resíduos poderia se mostrar economicamente viável. Conclusões: A maioria dos profissionais afirmou ter conhecimento de desenvolvimento sustentável e tentar preservar o meio ambiente quando descartavam os resíduos produzidos no consultório. Há dificuldade, por parte dos cirurgiões-dentistas, no descarte dos efluentes líquidos, mas grande parte consegue classificar e segregar adequadamente os resíduos do filme radiográfico. Descritores: Resíduos odontológicos. Resíduos tóxicos. Desenvolvimento sustentável. Radiografia.

The possibility of using phosphorus-containing wastewater as a raw material for the cultivation of the green algae strain Chlorella vulgaris ASLI-1 can represent an effective processing of phosphorus-containing by-products. A laboratory experiment was made to study the effect of the concentration of phosphorus-containing wastewater on the biomass density of the green alga strain Chlorella vulgaris ASLI-1. Three weeks after sowing, we measured the biomass density of algae in various components of the phosphorus-containing wastewater. Compared to the control (distilled water), the addition of phosphorus-containing wastes did not adversely affect the culture of green algae, with the exception of a 20% medium where algal cells were discolored and had a low biomass density, 104 CFU. However, more research is needed to better study the response of green algae to phosphorus-containing waste, to determine the amount of phosphorus in cells and solution. In addition, evaluate the agronomic efficiency of the Chlorella vulgaris ASLI-1 strain, cultivated on phosphorus-containing waste, when applying fertilizers for growing vegetables.

Palm Oil Mill Effluent (POME) is a liquid waste from palm oil factory that pollutes the environment but is very useful as a raw material for producing biogas. POME processing has advantages to meet environmental requirements and to produce commercialized products. Although there are already enough biogas systems installed in oil palm factories, there are handful of players in this sector who can design and install an optimal working plant on palm oil mill effluent. The design involves many parameters and quite complicated process. Apart from POME the palm oil mills also generate solid cake from their decanters which is also known as decanter muck or decanter cake. There are no biogas plants observed which were working on this decanter muck. The purpose of this study is to obtain an understanding about the biogas system utilizing solid decanter cake in Southern part of India. Various dilution rates were studied to understand the best possible feedstock to water ratio in terms of gas ...

As environmental impact of waste disposal has become a concern. Among the most pressing issues is the discharge of liquid waste into water bodies, which can cause severe ecological damage. To address this, Zero Liquid Discharge (ZLD) systems have emerged as a solution, particularly in India, where rapid industrial growth has heightened the need for sustainable waste management practices. ZLD systems, including Mechanical Vapor Recompression (MVR) and Agitated Thin Film Dryers (ATFD), offer comprehensive solutions for waste minimization and resource recovery. This article explores the significance of ZLD systems, the functioning of MVR and ATFD technologies, and profiles prominent manufacturers in India.

The subject of the study is the estimation of heavy metals (Cd Co ,Cu ,Fe, Mn, Pb, Zn) in the milk of livestock (cows, goats, sheep, camels) in AL-Hiswah protected, Aden, and comparing the results of the study with the permissible limits locally and internationally for the concentrations of heavy metals in raw milk. When the results were compared with the Yemeni food standards YS and the International Dairy Federation IDF; It turned out that all studied samples exceeded the permissible limit for lead and cadmium. On the other hand, copper concentration levels did not exceed the permitted limit, and when comparing the results of manganese, it was found that its concentration in cows, goats and camel milk is less than the permissible limit, but in sheep's milk it is slightly higher than the permissible limit according to Yemeni standards YS. The iron concentration in all study samples was much higher than the permissible limit according to the standards of the International Dairy Federation, while the zinc concentration appeared lower in milk samples (cows, goats, sheep) except for camels milk, which was found slightly higher than IDF standards.

Increasing cost of chemicals used in wastewater treatment has necessitated this study with a view to seek ways to increase efficiency and reduce cost of leather waste water treatment operation. Sampling of leather raw waste water was taken twice a week for laboratory test. The result of the Jar test experiment revealed that optimizing pH coagulant and flocculants doses metal removal from leather waste water can be accomplished. The test showed that pH value of 10 is the best optimum value for metals removal in the leather waste water. Further the results revealed that the metal removal in the waste water treatment plant requires applying the correct chemical dosage, adequate mixing, maintaining suitable pH value and controlling suspended solids in the effluent.

A multitude of tannery wastewater (TWW) is a key challenge for the tanning industry. Developing efficient and new technology is crucial to regulate the disposal of TWW. Many scientists developed a variety of types of membrane bioreactor-based technologies to treat TWW. This study performed a critical review to understand the existing membrane bioreactor-based TWW treatment technologies. The review revealed that many studies tried to understand the removal efficiency of the membrane bioreactor-based technologies for treating TWW. The study findings depicted that scientists tried to develop various types of membrane technologies, i.e., modified membrane bioreactor (MBR), anaerobic MBR, moving bed biofilm bioreactor (MBBR) and hybrid MBBR, osmotic membrane bioreactor (OMBBR), hybrid MBR. The MBBR technologies performed better than the existing MBR techniques among the currently employed MBR. The review suggests a set of future research domains for sustainable treatment of TWW by applying MBR. In the future, the research focus could be on the development of novel biocarriers, application of 3D printing and the implementation of process simulation to enhance process efficiency and sustainability.. The review will aid scientists in enhancing their comprehension of the processes associated with different MBR treatment technologies used for treating TWW. This will, in turn, accelerate the advancement of process parameters and techniques.

El sulfuro presente en el agua residual de la industria del curtido de cueros proviene de la operación de pelambre (depilado de la piel) en concentraciones que afectan significativamente la calidad del agua del cuerpo receptor debido a la toxicidad del vertimiento produciendo la mortandad de flora y fauna, responsable de la presencia de olores desagradables en el cauce y la notable disminución del oxígeno disuelto en el agua del afluente. En la presente investigación, la remoción de sulfuro es evaluada empleando la técnica cavitación hidrodinámica (CH), un proceso de oxidación avanzada analizado desde diferentes parámetros de operación como pH inicial del agua residual y presión de entrada para un tiempo de reacción fijo de 90 minutos; parámetros de diseño fueron establecidos mediante el uso de dos prototipos, variando el número y diámetro de orificios en el punto de estrangulamiento con el objetivo de determinar las condiciones óptimas del reactor para el tratamiento de este tipo d...

Methylene blue (MB) is released with the effluent from textile, leather, paper and other industries. Study was conducted to observe the removal efficiency of MB dye from aqueous solution by burned coal and eggshell as adsorbents. The concentration of MB decreased from 25 ppm to 2.102 ppm for burned coal as an adsorbent and from 25 ppm to 0.656 ppm for eggshell powder as an adsorbent. Adsorption capacity of eggshell was higher than burned coal at pH value of 7. Approximately 3 million tons of burned coal is produced every year in Bangladesh and the price of burned coal is only about BDT 3.00 per Kg. Large amount of eggshell is also produced every day and it is available in our country. So the burned coal and eggshell particularly eggshell could be an excellent low cost bio-adsorbent for cationic dye removal.

Residues of some medicals and fertilizers used in agricultural areas can reach to some receptors through some processes such as irrigation and surface waters. These natural receptors are rivers, lakes and seas. The materials coming from agricultural areas have more destructive effects on the lakes and rivers since these are smaller. The most pronounced pollutants coming from agricultural areas to rivers and lakes are pesticides and fertilizers which are known as a source of nitrogen and phosphor. Chemicals in some areas where pesticide were used are mixed into rivers and lakes through that way they reach to water habitats and organisms. On the other hand, this causes to increase organic ratio, eutrophication and for ecological balance to be destroyed. Pathogens are transmitted to surface waters with human and animal wastes and then these contaminated surface waters threat human health. An important amount of pathogens is distributed to receptors through use of wastewaters for irrigation. In order to this negative effects to be removed, in order to save rivers and lakes, wild irrigation must be stopped, the direct approach of wastewaters into the rivers and lakes must be prevented, the usage of fertilizers and pesticides must be controlled, mechanical and biological war must be strengthen. The sustainable ecological living areas can be constructed by taking the water sources and biological kinds under control with these precautions.

Phosphates are very important basic materials in agricultural and other industrial applications. Phosphorus is often present in low concentrations in wastewater, almost solely in the form of organic and inorganic phosphates (ortho-and poly-phosphates). The removal of phosphates from surface waters is generally necessary to avoid problems, such as eutrophication, particularly near urban areas. The usual methods of treatment are either biological or physicochemical by sedimentation. This paper studies the removal of phosphate species by adsorption onto calcite used as natural adsorbent. The phosphate solutions were prepared artificially by adding certain quantities of K 2 HPO 4 in water. The effect of equilibrium pH, phosphate/mineral ratio and contact time was studied. The results showed that pH plays an important role in the removal of phosphate species from solution, with removal being more efficient in the basic pH region. The experimental results also show that adsorption is also efficient for high ratios phosphate/adsorbent. Finally, the adsorption process is time dependant. Based on the experimental results a possible mechanism of phosphate removal onto calcite surface is proposed. As a general conclusion, phosphate species seem to be efficiently removed from solutions using calcite as natural adsorbent. In addition, the adsorption product can be used as fertilizer for acid soils.