Enhancing physico-chemical water quality in recycled dairy effluent through microbial consortium treatment

The dairy industry, notorious by generating wastewater rich in organic and nitrogenous content, necessitates sustainable recycling solutions. Biological treatment emerges as a cost-effective and chemical-free alternative. This study delves into the potential of microbial consortium, a microbial consortium, for recycling dairy effluent, aiming at water reclamation and environmental sustainability. Effluent samples from Madurai's Dairy Industry underwent microbial consortium treatment in a recycling prototype, with treatment efficacy assessed through physicochemical parameters and contaminant removal efficiency. Guided by a biodegradability index of 4.51, the study showcased EM's impact, revealing a notable decrease in pH levels, fostering an alkaline environment (2.35 ± 0.06 ppt). Dissolved oxygen increased significantly to 4.50 ppm, indicating improved aerobic conditions. EM treatment led to substantial reductions in calcium (53 %), magnesium (95 %), nitrogen (22 %), sulfate (79 %), phosphate (86 %), BOD (78 %), and COD (82 %). In contrast, dairy effluent treated without microbial consortium during the sludge activation process exhibited negligible water quality improvement. These findings underscore microbial consortium efficacy in advancing biological treatment of dairy effluent, demonstrating a significant reduction in contaminants and showcasing its potential for sustainable water reclamation. Improved alkalinity, dissolved oxygen, and nutrient content further signify positive impacts on ecosystem health. Microbial consortium emerges as a promising avenue for recycling dairy effluent, offering an economically viable and environmentally friendly solution. The study emphasizes the crucial role of microbial treatments in achieving efficient water reclamation, contributing to a cleaner and sustainable environment. Future research and broader implementation of microbial consortium in dairy industry wastewater management are recommended for enhanced environmental benefits.

Adsorptive removal of organic pollutants from milk-processing industry effluents through chitosan-titanium dioxide nanoadsorbent-coated sand

Milk-processing industry effluent (MPIE) poses severe problems for aquatic and environmental systems, especially in the South Asian region. Therefore, its treatment is of great interest. This study deals with the investigation of chitosan titanium dioxide nanoadsorbent (CTiO₂) coated onto sand particles via calcination that are used to remove the emerging pollutants. The adsorptive properties of these developed adsorbents are compared with those of the nascent sand without coating as well as with the chitosan titanium dioxide nanoadsorbent coated sand (CTiO₂-CS). Batch adsorption experiments were performed to investigate the percent reduction efficiency (%RE) of organic pollutants in terms of biological oxygen demand (BOD) and chemical oxygen demand (COD) from synthetic and real effluents. The maximum %RE of BOD (96.76) and COD (98.91) was achieved at 1.5 M dose of CTiO₂-CS, 120 min of contact time, pH 6.5, an initial BOD concentration of 900 mg/L, and an agitation speed of 400 rpm. Similarly, the %RE of COD was found to be 86.75 for synthetic effluent and 90.97 for real effluent at initial COD concentrations of 8000 mg/L. Pseudo-second-order and Langmuir models are found to be the best fits for BOD and COD adsorption. The diffusion model suggests that surface adsorption as well as intraparticle diffusion contribute to the actual adsorption process. Regeneration experiments were performed for four cycles, and CTiO₂-CS was found to be the most regenerable adsorbent material. The performance of the adsorbent was compared with previous studies, and it was found to have excellent adsorption capacity. As a result, the developed filter bed could be used as a promising superadsorbent for the removal of organic load in MPIE.

Application of Pistacia atlantica Leaves Powder as Natural Material To Remove Nitrate and Phosphate Ions From Domestic Wastewater by Characterization, Bio-removal, and Phytotoxicity Studies

Application of Pistacia atlantica Leaves Powder as Natural Material To Remove Nitrate and Phosphate Ions From Domestic Wastewater by Characterization, Bio-removal, and Phytotoxicity StudiesObaida Alhajali1* , Adnan Ali-Nizam1 , Rasha Almostafa2 1Damascus University, Department of Plant Biology, Damascus, Syria.2International University for Science and Technology, Department of General and Analytical Chemistry, Syria. Abstract: Description of Pistacia leaves powder using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Energy-dispersive X-ray spectroscopy (EDX), specific surface area according to nitrogen adsorption (SBET) and methylene Blue (MB), and point of zero charge determination (pHpzc). A series of batch adsorption tests were conducted to study effect of various factors (plant powders dose, contact time, temperature, pH) on the percentage of nitrate and phosphate removal from domestic wastewater. The adsorption kinetics, regeneration ability test of plant powder, and phytotoxicity tests for treated water and spent powder on germination were studied. Results of SBET analysis showed that Pistacia leaves powders have a low surface area and microscopic pores, SEM images revealed rough surfaces with uneven cavities, EDX analysis showed that there are high percentages of carbon and oxygen, good percentages for nitrogen, and few percentages of potassium, calcium, magnesium, phosphorous, sulfur and chlorine, and FTIR analysis showed that there are more than five distinct absorption peaks. The maximum value of nitrate and phosphate removal was 76.47% and 52.20%, respectively, at powder dose of 2 g/L, temperature 25 °C, and pH 5, and the percentage of nitrate and phosphate removal increased with increasing contact time until equilibrium was reached after 120 min for nitrate and 180 min for phosphate, and It was found that adsorption of ions follows kinetics of reaction from pseudo-second-order model, and powders can be Regeneration and used for two successive cycles with a slight decrease in removal efficiency. Germination tests on Lepidium sativum indicate no phytotoxicity. That is, Pistacia leaves powder is one of the natural products that are effective in removing nitrate and phosphate from domestic wastewater.

A comprehensive review on comparison among effluent treatment methods and modern methods of treatment of industrial wastewater effluent from different sources

In recent years, rapid development in the industrial sector has offered console to the people but at the same time, generates numerous amounts of effluent composed of toxic elements like nitrogen, phosphorus, hydrocarbons, and heavy metals that influences the environment and mankind hazardously. While the technological advancements are made in industrial effluent treatment, there arising stretch in the techniques directing on hybrid system that are effective in resource recovery from effluent in an economical, less time consuming and viable manner. The key objective of this article is to study, propose and deliberate the process and products obtained from different industries and the quantity of effluents produced, and the most advanced and ultra-modern theoretical and scientific improvements in treatment methods to remove those dissolved matter and toxic substances and also the challenges and perspectives in these developments. The findings of this review appraise new eco-friendly technologies, provide intuition into the efficiency in contaminants removal and aids in interpreting degradation mechanism of toxic elements by various treatment assemblages.

Azo-functionalized superparamagnetic Fe3O4 nanoparticles: an efficient adsorbent for the removal of bromocresol green from contaminated water

Water contamination is regarded as one of the world's worst tragedies owing to the continual depletion of water resources suitable for drinking and agriculture. Researchers have recently been interested in developing novel and more effective adsorbents for wastewater purification. We report herein a magnetic adsorbent nanomaterial for the removal of the anionic dye bromocresol green (BCG) from wastewater. The adsorbent is based on superparamagnetic iron oxide (cubic Fe₃O₄) nanoparticles (SPIONs) coated with a high-molecular-weight azo dye synthesized via diazo coupling of vitamin B1 with a trisubstituted benzene derivative. The proposed adsorbent was characterized using scanning electron microscopy, FTIR and ¹H-NMR spectroscopy, mass spectrometry, dynamic light scattering, vibrating sample magnetometry, thermal analysis, and X-ray diffraction crystallography. At room temperature and pH 2.0, the synthesized adsorbent showed an average particle size of 65.9 ± 8.0 nm, a high magnetization saturation (65.58 emu g⁻¹), a high equilibrium adsorption capacity (36.91 mg g⁻¹). Adsorption of BCG was found to take place via a physisorption mechanism and followed a pseudo-second-order rate kinetics. Thermodynamic studies revealed that the adsorption process is enthalpy driven by hydrogen bonding and/or van der Waals interactions. After treating water samples with the suggested adsorbent, it can be easily removed from water using a strong external magnetic field.

An efficient adsorbent based on azo-dye-coated superparamagnetic Fe₃O₄ nanoparticles was synthesized for the removal of the anionic dye, bromocresol green, from wastewater.

A Modified Lysimeter Study for Phyto-Treatment of Moderately Saline Wastewater Using Plant-Derived Filter Bedding Materials

The present study focuses on determining the phyto-treatment efficiency for treatment of moderately saline wastewater using organic raw materials, such as rice husk, coconut husk, rice straw, and charcoal. The moderately saline wastewater with total dissolved solids (TDS) concentration up to 6143.33 ± 5.77 mg/L was applied to the lysimeters at the rate of 200 m3 ha-1 day-1 in five different lysimeter treatments planted with Eucalyptus camaldulensis (T1, T2, T3, T4, and T5). T1 was a control without any filter bedding material, whereas rice straw, rice husk, coconut husk, and charcoal were used as filter bedding materials in the T2, T3, T4, and T5 treatment systems, respectively. Each treatment showed significant treatment efficiency wherein T3 had the highest removal efficiency of 76.21% followed by T4 (67.57%), T5 (65.18%), T2 (46.46%), and T1 (45.5%). T3 and T4 also showed higher salt accumulation, such as sodium (Na) and potassium (K). Further, the pollution load in terms of TDS and chemical and biological oxygen demand significantly reduced from leachate in the T3 and T4 treatments in comparison with other treatments. Parameters of the soil, such as electrical conductivity, exchangeable sodium percentage, and cation exchange capacity did not show values corresponding to high salinity or sodic soils, and therefore, no adverse impact on soil was observed in the present study. Also, Eucalyptus camaldulensis plant species showed good response to wastewater treatment in terms of growth parameters, such as root/shoot weight and nitrogen, phosphorus, and potassium (NPK) uptake, plant height, biomass, and chlorophyll content. Root and shoot dry weight were in the order T3 (51.2 and 44.6 g)>T4 (49.3 and 43.5 g) > T5 (47.6 and 40.5 g) > T2 (46.9 and 38.2 g) > T1 (45.6 and 37.1 g). Likewise, the total chlorophyll content was highest in T3 (12.6 μg/g) followed by T4 (12.3 μg/g), T5 (11.9 μg/g), T2 (11.5 μg/g), and the control, that is, T1 (11.0 μg/g). However, the most promising results were obtained for T3 and T4 treatments in comparison with the control (T1), which implies that, among all organic raw materials, coconut and rice husks showed the highest potential for salt accumulation and thereby wastewater treatment. Conclusively, the findings of the study suggest that organic raw material-based amendments are useful in managing the high salts levels in both plants and leachates.

A novel approach to baseline water quality assessment at local and catchment scale: a case study from Berambadi, India

Optimal design and maintenance are necessary for the sustainability of wastewater treatment systems. In this study, we present the outcome of a novel approach to baseline assessment conducted prior to the design and deployment of a decentralized wastewater treatment system at a school in rural India. The baseline water quality monitoring protocol was deployed to assess (a) the quality and quantity of wastewater (greywater and blackwater) flows from the school and (b) the status of surface water and groundwater quality in the catchment. Hourly greywater flows and water quality trends were monitored across four seasons at the school. Average freshwater consumption at the school was 518 ± 322 L/day for hand washing and 287 ± 97 L/day for cooking meals. Greywater generation showed high hourly variations in COD levels. Greywater generated from hand wash and kitchen sources contributed to 110 g/day and 96 g/day of BOD₅ respectively and 214 g/day and 141 g/day of COD respectively. Based on additional data from a self-reporting sanitation survey, the organic contaminant load generated from the toilet was estimated to be 1.5 ± 0.1 kg COD/day. At the catchment scale, both groundwater and surface water quality were monitored seasonally to assess the impact of raw sewage and stormwater inputs. Compared with borewells, high nitrate-N levels (> 10 mg/L) were observed in the village hand pump samples throughout the year. Maximum nitrate-N (16 mg/L) and fecal coliforms (3.9 log MPN/100 mL) levels were observed in surface waters during monsoons, indicating the impact of sewage and surface runoff on water quality. The proposed approach is useful to estimate data on freshwater use and wastewater generation at the school and hence to make the case for, and design of, a sustainable water management intervention.

Comparison of chitosan based nano-adsorbents for dairy industry wastewater treatment through response surface methodology and artificial neural network models

The present investigation was focused to compare chitosan based nano-adsorbents (CZnO and CTiO₂) for efficient treatment of dairy industry wastewater using Response Surface Methodology (RSM) and Artificial Neural Network (ANN) models. The nano-adsorbents were synthesized using chemical precipitation method and characterized by using scanning electron microscope with elemental detection sensor (SEM-EDS) and atomic force microscope (AFM). Maximum %R_BOD (96.71 and 87.56%) and %R_COD (90.48 and 82.10%) for CZnO and CTiO₂ nano-adsorbents were obtained at adsorbent dosage of 1.25 mg/L, initial biological oxygen demand (BOD) and chemical oxygen demand (COD) concentration of 100 and 200 mg/L, pH of 7.0 and 2.00, contact time of 100 and 60 min, respectively. The results obtained for both the nano-adsorbents were subject to RSM and ANN models for determination of goodness of fit in terms of sum of square errors (SSE), root mean square error (RMSE), R² and Adj. R², respectively. The well trained ANN model was found superior over RSM in prediction of the treatment effect. Hence, the developed CZnO and CTiO₂ nano-adsorbents could be effectively used for dairy industry wastewater treatment.

Phenomena of Removal of Crystal Violet from Wastewater Using Khulays Natural Bentonite

The study investigates the phenomena involved in the crystal violet (CV) removal using the Khulays natural bentonite from the wastewater. The batch technique was utilized for performing the adsorption experiments. The operating systems were used for the investigation of the adsorption behaviour in the study, which included the initial CV concentration, time taken for shaking, the dosage of adsorbent, and the initial solution pH. The Freundlich isotherm framework and the Langmuir data were assessed in the experiment. The study outcome revealed that the equilibrium in the study was reached when shaking takes place for about 40 minutes. Additionally, the data of the sorption revealed that the enhancement of the CV concentration at the start mitigates the percentage of the CV removal as a result of which saturation integration in the Khulays bentonite dye occurs. The initial improvement in the solution pH led to improved CV adsorption. The data achieved at the isotherm adsorption were found adequate with the frameworks of Freundlich isotherm and Langmuir. Along with it, the model of pseudo-second-order kinetics was used to exhibit the adsorption of crystal violet with the Khulays natural bentonite. The Khulays natural bentonite adsorption of CV was demonstrated by the thermodynamic data exhibiting its spontaneous as well as endothermic nature. The study concludes that basic dyes can be effectively removed from the wastewater by the use of Khulays natural bentonite.

The effects of biochar and rice husk on adsorption and desorption of cadmium on to soils with different water conditions (upland and saturated)

Hard wood derived biochar (BCH) and rice husk (RCH) were applied to soils having upland and saturated conditions to investigate their effects on adsorption and desorption of Cd by conducting incubation and batch experiments. The results obtained from the experiments indicated that BCH increased Cd sorption by 59-71% onto saturated soil (SS), while by 57-84% onto upland soil (US). The application of RCH also increased the sorption of Cd onto the soils under both water conditions but the increases were less as compared to BCH. With RCH application, 21-41% increases in sorption of Cd on SS and 38-54% on US soils were observed. The Langmuir equation fitted sorption of Cd better than Freundlich with R² > 0.95 for all selected treatments. Both electrostatic and non-electrostatic mechanisms played their important roles in the adsorption of Cd in the amended soils. BCH enhanced non-electrostatic adsorption as compared to RCH and thus control and induced greater specific adsorption capacity. High desorption percentage of pre-adsorbed Cd on soils were observed both with and without amendments. Decreases in desorption percentage of pre-adsorbed Cd on both soils were observed with BCH with a highest decrease on SS (39%). The application of selected amendments into different soils increased Cd adsorption of soils through both electrostatic and non-electrostatic mechanisms and the contribution of both the mechanisms varied with types of amendments and soil conditions. BCH material showed promising results in Cd adsorption as compared to RCH for different selected soils and conditions but cost-benefit analysis is needed in field condition.