Coagulation-flocculation Process Research Articles

Coagulation-flocculation process on a lattice: Monte Carlo simulations

Abstract Coagulation-flocculation, the physicochemical process widely used for purification a wastewater, is affected both by chemical details of involved polymers and by the statistics of their conformations on a large scale. The latter aspect is covered in this study by employing a coarse-grained modelling approach based on a combination of two paradigms of statistical mechanics. One is the self-avoiding walk (SAW) which generates a range of conformations for a linear polymer of $N_{{\rm SAW}}$ monomers. Another one is a non-trivial diffusion limited aggregation (DLA) process of $N_{{\rm DLA}}$ impurities (referred thereafter as ``particles") which describes their coagulation occurring with the probability $0< p \leq 1$ ($p=1$ recovers a standard DLA). DLA of diffusive particles is complemented by their irreversible adsorption on the SAW monomers occurring with the probability equal to one, both processes resulting in formation of the DLA-SAW agglomerates. The dynamics of formation of such agglomerates, as well as their fractal dimensions and internal structure are of practical interest. We consider a range of related characteristics, such as: (i) absolute $N_a$ and relative $n_a$ adsorbing efficiencies of SAW; (ii) effective gyration radius $R_{g {\rm DLA-SAW}}$ of the DLA-SAW agglomerates; and (iii) the fractal dimension $D_{{\rm DLA-SAW}}$ of these aggregates. These are studied within a wide range for each parameter from a set $\{p,N_{{\rm DLA}},N_{{\rm SAW}}\}$.

Magnetic coagulant derived from Cassia fistula seed for real textile wastewater treatment: A pilot-scale study

Cassia fistula (C. fistula) seed-derived coagulants have demonstrated substantial potential for treating dye-based wastewater. Such coagulants exhibit notable coagulating-flocculating activity and are environmentally friendly. However, recovering these natural coagulants from aqueous media poses challenges. In this study, we introduce a novel plant-derived magnetic coagulant that is a combination of C. fistula seed gum with magnetic spinel ferrite. This research includes a pilot-scale study to simulate full-scale textile wastewater treatment using this composite. Material characterisations revealed that spherical CoFe2O4 particles could be effectively coated with the active coagulant, C. fistula gum. The saturation magnetisation of the composite, measured at 54.11 emu/g, facilitates its convenient separation from aqueous solutions using an external magnetic field. Bench-scale studies showed that initial pH and coagulant dosage substantially affect the removal efficiency of colour and chemical oxygen demand (COD). In the pilot-scale study, the C. fistula–CoFe2O4 composite demonstrated promising coagulant properties. It achieved a colour removal percentage of 94.0 % with a volume of 30 L and a coagulant dosage of 12.3 g L− 1. Using this coagulation–flocculation process as a primary treatment step, possibly followed by biological or membrane methods, can help meet Vietnamese environmental standards.

Avocado seed as a natural coagulant for removing dyes and turbidity from wastewater: Behnken Box design, sustainable reuse, and economic evaluation

In wastewater treatment, conventional coagulants are becoming very complex with environmental concerns. For this purpose, using an alternative natural coagulant such as fruit waste becomes essential. This study explores the potential of avocado seed powder as a novel biocoagulant for treating wastewater contaminated with dyes and turbidity. It was characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, Scanning Electron Microscopy coupling with Energy-dispersive X-ray spectroscopy, and X-ray fluorescence. The coagulation-flocculation process was optimized using a Box-Behnken design, evaluating the effects of coagulant dose (300–1000 mg. L−1), initial solution pH (3–9), and granulation (63–112 μm), on the removal of methylene blue, crystal violet, and turbidity. The response surface methodology revealed statistically significant quadratic models (R2 > 0.94) for maximizing pollutant removal. Under optimal conditions (1000 mg. L−1 dose, pH 9, 63 μm granulation for methylene blue; 950 mg. L−1, pH 7, 108 μm for crystal violet; 300 mg. L−1, pH 8, 63 μm for turbidity), avocado seed powder achieved maximum removal efficiencies of 94.34 % for methylene blue, 95.28 % for crystal violet, and 99.64 % for turbidity. Characterization techniques confirmed the involvement of avocado seed powder in the coagulation-flocculation mechanism. The biocoagulant has demonstrated significant reuse potential over five cycles. It also has a low estimated cost, of the order of 0.008–0.025 USD. m−3 as agricultural waste, compared with 1.5 USD. m−3 for aluminum sulfate. Overall, avocado seed is a sustainable and promising natural coagulant for wastewater treatment.

Removal of Dyes from Water Using Aluminum-Based Water Treatment Sludge as a Low-Cost Coagulant: Use of Response Surface Methodology

The aim of this research was to valorize waste (sludge) from a drinking water treatment plant as a coagulant in the removal of dyes (methylene blue and crystal violet) from water and to prevent environmental issues associated with sludge storage. To accomplish this purpose, the response surface methodology based on a central composite design with five levels was implemented. In order to enhance the efficacy of the coagulation–flocculation process, three key operational variables were considered for optimization: the pH, coagulant dosage (mg/L), and initial dye concentration (mg/L). To achieve this, a quadratic polynomial model was established. According to the mathematical model that has been developed, it is predicted that the highest efficiency for removing dyes is 94.44%. This maximum effectiveness is reached when the pH is adjusted to 12.04, the coagulant dose is set at 87.044 mg/L, and the dye concentration of MB is maintained at 2.955 mg/L. Conversely, the best dye removal of CV was attained at 100% under the following conditions: pH = 12.045, a coagulant dosage of 2.955 mg/L, and a dye concentration of 2.955 mg/L. The R2 (98.44% and 95.80% for MB and CV, respectively) validated both models. In this work, the coagulant was characterized by the surface charge, FTIR, BET, and SEM analysis.

Optimization use of watermelon rind in the coagulation-flocculation process by Box Behnken design for copper, zinc, and turbidity removal

Watermelon rinds were investigated as a bio-coagulant for treating water contaminated by metals and turbidity, owing to their biodegradability and greater environmental friendliness compared to chemical coagulants. Fourier transform infrared spectroscopy, scanning electron microscopy paired with energy dispersive X-ray analysis and X-ray diffraction characterized the watermelon rinds before and after use. A Box-Behnken experimental design optimized the most influential parameters of initial pH, coagulant dose, and particle size based on response surface methodology. This analysis revealed the experimental data fit quadratic polynomial models, achieving maximum removal efficiencies of 97.51 % for zinc, 99.88 % for copper, and 99.21 % for turbidity under optimal conditions. Statistical analysis confirmed the models effectively captured the experimental data. Analysis of variance denoted the high significance of the quadratic effects of dose and pH. Removal of metal ions Zn2+ and Cu2+ was significantly impacted by these factors. The watermelon rind powder retained its coagulation efficiency after five cycles of reuse, with removal rates of 80.04 % for Zn, 88.33 % for Cu and 86.24 % for turbidity. These results demonstrate the potential of watermelon rind as an alternative coagulant for wastewater treatment. Further testing on real industrial effluents at larger scales would help assess their feasibility for real-world applications.

Optimization of coagulation-flocculation process for wastewater treatment from vegetable oil refineries using chitosan as a natural flocculant

Vegetable oil refinery wastewater (VORW) is a significant source of refractory pollutants necessitating efficient treatment prior to discharge. This study investigates the treatment of VORW via coagulation-flocculation using ferric chloride (FeCl3) as a coagulant and chitosan as a natural flocculant. Central Composite Design (CCD) is employed to optimize the treatment process and assess the interplay of experimental factors. The study evaluates turbidity, COD, and polyphenols as responses, with pH, FeCl3 concentration, chitosan dosage, and agitation time as independent factors.The results showed that the optimal conditions identified include pH 6, FeCl3 dosage of 1.6 g/L, chitosan dosage of 13.4 mg/L, and agitation time of 26 min, resulting in 100 % turbidity removal, 86 % COD reduction, and 90 % polyphenol removal. The analysis of variance indicated that the established models were significant and that they are characterized by a good fit (R2 in the order of 0.95, 0.96, and 0.96 for turbidity, COD, and polyphenols, respectively).These findings highlight the efficacy and sustainability of the coagulation-flocculation process with chitosan, offering a practical, rapid, and cost-effective solution for VORW treatment and environmental preservation.

EVALUATION OF THE COAGULANT EFFICIENCY OF MORINGA SEED (MORINGA OLEÍFERA) FOR THE WATER TREATMENT OF THE CHURÍN RIVER, PACHANGARA DISTRICT, LIMA, PERU

Background: In the research, Moringa Oleifera - MO seeds were used in coagulation-flocculation processes, identifying the main properties it presents such as coagulant activity. Aims: The purpose of the research was to evaluate the coagulant and flocculating effect of moringa seed flour in the treatment of turbid water (with turbidity between 700 NTU and 800 NTU). Methods: The experimental tests were carried out under the following conditions: shelled moringa seed flour in NaCl solution, 1 M, it was observed that it has no effect on the clarification of turbid water and modifies the pH to 4.47; The mixture of moringa seed flour with aluminum sulfate (Aquapol brand) was investigated in jar tests with 300 mL of turbid water at conditions of: shelled moringa seed flour 1.02 g, 5.01 g and 10, 02 grams; with aluminum sulfate 0.1 mL, 0.5 mL, and 0.7 mL, respectively; at 200 rpm for 2 minutes, Results: Evaluating water quality after 1.5 h and 12 h of sedimentation; It was determined that the best performance was the mixture of: 1.02 g of moringa seed flour with 0.1 mL of aluminum sulfate, 200 rpm for 2 minutes, then at 70 rpm for 15 minutes and 12 h of sedimentation. Discussion: Experimental tests have been carried out using Moringa Oleifera (MO) for raw river water treatment processes in places of low economic availability and due to its abundant availability, low cost, and non-toxic. Conclusions: It was concluded that its most viable application would be as a flocculation adjuvant, since, when used with a Chemical coagulant, it reduces the concentration of the chemical coagulant with good removal results.

Modeling and Optimization of Coagulation-Flocculation Process to Remove High Phosphate Concentration in Wastewater from a Metal-Mechanic Industry

Modeling and Optimization of Coagulation-Flocculation Process to Remove High Phosphate Concentration in Wastewater from a Metal-Mechanic Industry

Impact of Conditioning Agent Addition Sequence on Dewatering Performance of Advanced Anaerobic Digested Sludge

The advanced anaerobic digestion process enhances sludge resource utilization. However, thermal hydrolysis pretreatment of anaerobically digested sludge reduces dewatering efficiency due to excessive organic matter decomposition. This necessitates significant time and effort for sludge conditioning in wastewater treatment plants. Using conditioning agents can achieve high dewatering efficiency. This study investigates how the order of adding coagulants and flocculants impacts the dewatering performance of digested sludge. The results indicate that, compared to the flocculation–coagulation process with the same dosage, the coagulation–flocculation process leads to a 15–20% increase in the average particle size of digested sludge. The content of polysaccharides and proteins in S-EPS decreases by 28.8–30.8% and 10.1–11.3%, respectively. The filter cake solids content increases by 8.5%, and there is an increase in surface water channels within the flocs. This is because initially adding coagulants efficiently adsorbs small particles, forming larger aggregates that settle effectively. This promotes the breakdown of extracellular polymeric substances, releasing more bound water. Adding flocculants later bridges the aggregates, further enhancing settling and filtration performance, thereby improving sludge dewatering efficiency. These research findings contribute to a better understanding of the mechanisms of coagulant and flocculant co-conditioning for digested sludge and provide recommendations for optimizing sludge conditioning steps.

Removal of lead in water by coagulation flocculation process using Cactus-based natural coagulant: optimization and modeling by response surface methodology (RSM).

The aim of this research is to study the ability of Cactus leaves to act as a biocoagulants for the removal of lead in water. Different solvents, such as distilled water, NaCl, NaOH, and HCl, were used as chemical activators to extract the active components from the Cactus. The Cactus was utilized as an organic coagulant in five different forms: (i) Cactus juice (CJ); Cactus extract using (ii) distilled water (C-H2O); (iii) NaCl at 0.5M concentration (C-NaCl); (iv) NaOH at 0.05M concentration (C-NaOH); and (v) HCl at 0.05M concentration (C-HCl). In order to establish the optimal conditions for the coagulation, this study employed the jar test as an experimental technique and the Box-Behnken design (BBD) as an experimental approach. According to BBD, there are three factors (k=3), namely pH, biocoagulant dosage, and settling time. The R2 and R2 adjusted for all coagulants were close to 100%, confirming the validity of all the mathematical models. The results were significant; the highest lead removal efficiencies were 98.11%, 98.34%, 95.65, 96.19%, and 97.49%, utilizing CJ, C-H2O, C-NaCl, C-HCl, and C-NaOH as natural coagulants. The Cactus has been characterized using FTIR, XRD, and SEM to identify the active components that remove lead.

Effect of sludge resulting from biocoagulation-flocculation process on Abelmoschus esculentus L. growth

The current study was performed to determine the effect of sludge resulting from biocoagulation-flocculation process on okra (Abelmoschus esculentus L.) growth. The effectiveness of the resultant sludge collected after coagulation-flocculation of aquaculture effluent using biocoagulant-flocculant was compared with garden soil (nutrient rich medium) and also with sand (nutrient deficiency medium). The growth of plants in terms of physical observation and also the agronomic parameters (the number of leaves and the height of plants) was monitored for 8 weeks. At the end of the exposure period, there is no significant difference in terms of the number of leaves and also the height of plants between plants in garden soil and plants in pots with the resultant sludge. In contrast, the agronomic parameters for plants in pot with sludge were significantly higher than plants in pot with sand only. As for the relative growth rate (RGR) of plants, plants in pots with sludge were the highest (3.84 g/week) compared to garden soil (3.52 g/week) and sand only (0.25 g/week). It can be concluded that sludge generated from the coagulation-flocculation process of aquaculture effluent using natural resources as coagulant-flocculant agent has given positive impact on the growth of okra plants and is potentially utilized as biofertilizer for plants.

A holistic approach to the recovery of valuable substances from the treatment sludge formed from chemical precipitation of fruit processing industry wastewater

In this study, recovery of phenolic substances with Soxhlet extraction, (SE) ultrasound-assisted extraction (UAS), and supercritical CO2 (SC-CO2) extraction methods from chemical sludge obtained with chemical precipitation (FeCl3/PACS, Ca(OH)2/PACS, perlite/PACS, FeCl3/cationic polyelectrolyte) of lemon processing wastewater was investigated. The effect of used coagulants/flocculants and pH on COD and total phenolic substance content (TPC) removal was researched. Recovered phenolic substance profiles were also determined with HPLC-DAD. Additionally, response surface methodology was used to determine optimum treatment conditions. ANOVA analysis showed that pH is a more important variable than coagulant/flocculant doses for all chemical precipitation experimental sets. The highest removal efficiencies for COD and TPC was obtained in FeCl3/PACS (COD: 72.0 %, TPC: 93.7 %). Optimum dose values were determined as pH: 4, FeCl3: 3000 mg/L, PACS: 400 mg/L for FeCl3/PACS, pH: 6.5, Ca(OH)2: 1500 mg/L, PACS: 300 mg/L for Ca(OH)2/PACS, pH: 5.5, PACS: 7000 mg/L, perlite: 50 g/L for perlite/PACS, pH: 4.5, FeCl3: 500 mg/L, polyelectrolyte: 4 mg/L for FeCl3/polyelectrolyte. TPC removal efficiencies were determined as 55 %, 35 %, 57 % and 58 % in these conditions, respectively. Maximum TPC in extracts was determined as 39.03 mg GAE/g extract, 8.81 mg GAE/g extract, and 4.34 mg GAE/g extract for SE, UAS, and SC-CO2, respectively. TPC recovery efficiencies (RTPC) for all chemical sludge were SE > UAS > SC-CO2. Additionally, the TPC profile has shown a difference depending on the extraction method.According to the results of this study, it was concluded that the coagulation-flocculation process may be a suitable alternative for fruit juice processing industry wastewater in terms of both reducing environmental pollution and recovering polyphenolics from formed sludge. Consequently, this study presented a different perspective on the recovery from wastes with valuable substance recovery from chemical sludge.

Feasibility of UVA photocatalytic post-treatment of molasses wastewater: Effects on melanoidins removal, mineralization and oxidation of ammoniacal-nitrogen

The brown color of molasses wastewater is due to the presence of melanoidins which are toxic to human health and environment. In this study, combination of coagulation-flocculation process with UVA-photocatalytic degradation of raw and diluted molasses wastewater in the presence of zinc oxide (ZnO) and titanium dioxide (TiO2) as photocatalyst was investigated. The effect of various operating parameters, such as light irradiation, aeration, catalyst dosage and pH of molasses wastewater on the photocatalytic degradation process was examined. The pre-treated diluted molasses wastewater (2 DF) showed greater performance compared to pre-treated raw for both photocatalysts due to high penetration of light into the wastewater. The formation of •OH enhanced color intensity reduction rate of pre-treated raw and 2 DF molasses wastewater in the presence of light irradiation and aeration. The color removal efficiency of pre-treated raw and 2 DF molasses wastewater was better in alkaline medium (pH 10) when ZnO used as photocatalyst, meanwhile it achieved higher removal efficiency in acidic medium (pH 4) when TiO2 was used as photocatalyst. The mineralization and oxidation of ammoniacal-nitrogen of molasses wastewater showed enhanced performance in photocatalytic treatment.

Otomotiv Endüstrisi Atıksularının Koagülasyon- Flokülasyon, Fenton ve UV/H2O2 Prosesleri ile Arıtılabilirliğinin İncelenmesi

In the automotive industry, painting operations have emerged as a major source of environmental concerns. In this study, the treatability of wastewater obtained from the automotive industry painting process was investigated by using coagulation-flocculation, ultraviolet/hydrogen peroxide (UV/H2O2), and Fenton processes. The effects of pH, coagulant, and anionic polymer doses were examined for three different coagulants in the coagulation-flocculation process. Optimal conditions were determined based on chemical oxygen demand (COD) and turbidity removal efficiency. As a result of the study, the optimum conditions for the coagulant identified as ferric chloride, which achieved the highest COD removal of 49.6% and turbidity removal of 74.4%, were determined as pH 8, coagulant dose of 400 mg L-1, and anionic polymer dose of 1 mg L-1. In the second stage of the study, Fenton and UV/H2O2 processes were applied to the effluent of the coagulation-flocculation process to increase the removal efficiency. When the results were evaluated, it was observed that the maximum COD removal efficiency of 63.4% was attained under the conditions of pH 3 and 400 mg L-1 H2O2 concentration applied in the UV/H2O2 process. However, in the Fenton process, a maximum COD removal efficiency of only 51% was achieved. From this study, it can be concluded that the UV/ H2O2 process applied after coagulation-flocculation increases the removal efficiency and can be an alternative and effective treatment process for wastewater from the automotive painting process.

Application of grape seed and Austrocylindropuntia mucilage for the simultaneous removal of azo dye and turbidity from synthetic wastewater: Optimizing experimental conditions using Box-Behnken Design (BBD)

The purpose of this study was to explore the potential of grape seed powder (GSP) as a natural coagulant and Austrocylindropuntia mucilage (AM) as a natural flocculant to efficiently eliminate both Congo red (CR) azo dye and turbidity from synthetic wastewater using coagulation-flocculation technique. The Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy dispersive spectra (EDS) mapping, and X-ray photoelectron spectroscopy (XPS) techniques were used to characterize natural plants employed as well as sludge formed after coagulation-flocculation process. Moreover, response surface methodology (RSM) approach was established via Box-Behnken Design (BBD) to optimize a set of coagulation-flocculation conditions; including GSP dose, AM dose, initial pH, initial CR concentration, initial turbidity, and settling time. RSM-BBD results showed highest removal efficiency of 99.36 % and 95.74 % of CR and turbidity, respectively, achieved under optimum conditions of 0.45 mg L−1 of GSP coagulant, 6 mL L−1 of AM flocculant, at pH of 10, initial CR concentration of 5 mg L−1, initial turbidity of 250 NTU, and after settling time of 120 min. The findings of this work revealed that there are multiple mechanisms involved in CR and turbidity removal, namely hydrogen bonding, electrostatic interactions, π-π interactions, and bridging effect.

Phytotoxicity assessment of treated vegetable oily wastewater via environmentally coagulation/flocculation and membrane filtration technologies using lettuce (Lactuca sativa) seeds.

The present investigation highlights the necessity of monitoring some basic physico-chemical water quality indicators and their phytotoxic effect using ecotoxicological bioassays such as "seed germination tests." The phytotoxicity of raw and treated vegetable oil refinery wastewater (VORW) using different treatment processes was assessed through some physiological responses (relative seed germination (RSG), seedling elongation, and germination index (GI)) using Lactuca sativa cultivar. Biotest results of different raw water samples revealed a noticeable correlation between the organic matter content and water phytotoxicity. In fact, VORW showed a very low RSG (17 ± 0.7 to -47 ± 0.58%) and high phytotoxic effects (GI < 50%). The use of coagulation/flocculation (CF) allowed a satisfactory phytotoxicity removal where RSG obtained ranged from 83 ± 1.58 to 90 ± 1.2%. However, the effluent still presents high to moderate phytotoxicity since GI remained below 80% which indicates the presence of toxic elements remaining after CF treatment. When VORW were treated using membrane processes, their phytotoxicity was gradually decreased with the decrease in the membrane pore size. The use of microfiltration membranes (MF), with pore size of 5 µm, 1.2 µm, 0.45 µm, and 0.22 µm, showed RSG values ranged from 37 ± 1.15 to 77 ± 1.68% and GI of less than 80% indicating a moderate to high phytotoxicity. However, the use of ultrafiltration (UF) membranes with molecular weight cut-off (MWCO) of 100 kDa, 30 kDa, and 10 kDa made it possible to achieve an RSG of 100% and an IG exceeding 80% showing that the VORW-treated using UF does not exhibit any phytotoxicity effect. Hence, UF appears to be the most efficient and environmentally friendly technology that could be used for safely treated VORW irrigation purposes compared to CF and MF processes.

Aquaculture wastewater treatment using plant-based coagulants: Evaluating removal efficiency through the coagulation-flocculation process

The ability of mixed neem, cassava, and wild betel plant leaves to act as plant-based coagulants was tested in real aquaculture wastewater through the coagulation-flocculation process. The performance of plant-based coagulant (PBC) was compared with that of chemical coagulant (alum) to observe the removal efficiency of turbidity, TSS, color, and COD. Ratio, as a new approach, was used by selecting TSS as an indicator or index to substitute for the dosage term and calculated based on a simplified equation. The extracted medium for these coagulants was prepared by using water extraction. Initial characterizations showed that the PBC had some carbon and amine groups (as also confirmed by LC-MS) with an average zeta potential of –22.83 ± 0.62 mV. Results indicated both coagulants (plant-based and chemical coagulants) successfully removed the measured polluted parameters of turbidity (85.17 %), TSS (80.28 %), color (59.42 %), and COD (54.63 %) for PBC with dosage of 0.79 mg/L and coagulant mass of 3.94 mg, while alum gained a higher removal with turbidity (99.08 %), TSS (98.71 %), color (97.29 %), and COD (75.31 %) with dosage and coagulant mass of 698.4 mg/L and 349.2 mg, respectively. This signaled that alum still acted as the best coagulant, but PBC showed a promising opportunity as a potential substitute for chemical coagulant.

Chemical oxygen demand removal from wet coffee processing wastewater using indigenous natural coagulants: Optimization through response surface methodology

This study was carried out to examine the possibility of treating the wastewater from coffee processing using a number of natural coagulants, both alone and in combination, and also the central composite design (CCD) was used for process optimization. To examine and study the potential treatment of chosen natural coagulants for chemical oxygen demand (COD) removal in the wastewater from coffee processing, a coagulation-flocculation process experiment was carried out. The numerical and experimental optimization system's optimum conditions and outcomes were investigated. A series of batch experiment have been performed for analyzing and optimizing of the coagulation flocculation processes. Based on the experimental analysis, it was found that utilizing a blend of three coagulants—Acanthus sennii C., Moringa stenopetala B., and Aloe vera L., yielded optimal results as a natural coagulant. Under these conditions, the ideal parameters for coagulant dosage, pH level, mixing speed, and mixing time were determined to be 1.25 gL−1, 7, 80 rpm, and 30 min, respectively, in the experimental work. In comparison, the numerical values for these parameters were coagulant dosage-0.750 gL−1, pH-8.76, mixing speed-80.73 rpm, and mixing time-19.23 min, respectively. The COD removal effectiveness under optimal responses from experimental and numerical was about 98.24% and 98.41%, respectively. Even though all coagulants are ideal, it was discovered that employing a mixed kind of coagulant produced better results than using a single type.

Coagulation-flocculation parameters for simultaneous removal of nitrates, nitrites, phosphates, and ammonium from wastewater: A mini review

This mini review delves into the critical need to effectively eliminate nitrates, nitrites, phosphates, and ammonium from wastewater to mitigate environmental pollution and uphold water quality standards. Stemming from various human activities like agricultural runoff, industrial processes, and municipal discharges, these pollutants pose significant risks to both aquatic ecosystems and human health if left unaddressed. The study primarily focuses on the efficacy of coagulation-flocculation as a treatment method, which involves the addition of chemicals known as coagulants to destabilize the pollutants. The review further examines the influence of various parameters such as pH, coagulant dosage, and temperature on the simultaneous removal of these contaminants [1,2]. Through detailed analysis, it elucidates the complex interactions among these factors and their consequential impact on overall removal efficiency. Moreover, it underscores the significance of adopting advanced treatment methods like coagulation-flocculation. Additionally, it emphasizes the ongoing need for further research and optimization to address the evolving challenges of wastewater pollution and water resource management comprehensively. By providing insights into optimizing coagulation-flocculation processes, this review underscores the importance of tailored treatment strategies for comprehensive pollutant removal.

Effect of adding biochar from prickly pear skin to aluminium sulphate to improve the coagulation-flocculation process during the elimination of humic substances present in the Laghrous drainage canal Water, Zab El-gharbi region (SE Algeria)

The objective of this research is to enhance the elimination of humic substances found in agricultural drainage water using a two-fold approach: coagulation-flocculation using aluminum sulfate both separately and in combination with powdered activated carbon made from prickly pear skin. To attain our goal, laboratory jar test were conducted on synthetic solutions. Several reaction parameters were examined, including the impact of changing coagulant dosage, impact of temperature, and adjusting pH levels. The results obtained demonstrated that the flocculation process is more effective in reducing compounds with higher molecular masses. Compared to a 49% removal rate with aluminum sulfate alone, the addition of an adjuvant powdered activated carbon made from the skin of prickly pears greatly improved the elimination process, resulting in removal rates of 92%, 84%, and 79% for powdered activated carbon masses of 0.50 g/L, 0.20 g/L, and 0.10 g/L, respectively. Throughout this investigation, we will showcase the outcomes derived from the tests performed on synthetic solutions containing model organic compounds (commercial products) dissolved in distilled water, alongside the analysis of agricultural drainage waters. The study investigates the influence of various reaction parameters on the removal efficiency of humic substances through coagulation-flocculation using aluminum sulfate. The results show also that in the presence or in the absence of powdered activated carbon derived from the skin of prickly pear, the coagulation is more eficient at low pH (5 to 6). In addition, we have show that simple coagulation flocculation remove only 66% of Chemical oxygen demand (COD) of initial value and the presence of powdered activated carbon (40 mg.L-1) increases efficiency up to 82%. To enhance this process, the addition of a water additive is considered to improve treatment efficiency.