Washing Wastewater Research Articles

Production status, economic benefit and environmental impact of lanolin cholesterol

The main pollutants in wool washing wastewater are lanolin and surfactants, which are difficult and expensive to treat. Lanolin, as a natural raw material widely used in cosmetics, pharmaceuticals, leather, and other fine chemical fields, has great economic value. The chief aim of this paper is to summarize the development status and indirectly environmental impact of lanolin derivatives, compare the cholesterol content data of lanolin samples commonly used in the world through experimental means, and provide guidance and suggestions for the raw material selection of lanolin cholesterol production plants in the future. The method used in this study is known as nuclear magnetic resonance: the author tests and compares the cholesterol standard sample and other 3 different unprocessed lanolin samples. The research has recorded valuable data about the unprocessed lanolin from Ningxia, China contains the highest amount of cholesterol. Therefore, the result of this study provides feasible advice for the lanolin cholesterol production factories when selecting the production’s raw material; also, the conclusive method of cleaning wool-washing waste water provides instructive idea for the factories that produce lanolin derivatives.

Escherichia coli as a sentinel in the assessment of antimicrobial resistance in the tilapia production chain: from production environment to the final product

IntroductionThe intensification of tilapia production has increased animal density in tanks, leading to more frequent exposure to pathogenic agents and compromising the quality of fish products. Antimicrobial resistance is a global concern that affects human treatment, and sentinel microorganisms like Escherichia coli are crucial for monitoring production chains, especially in aquaculture, where research is still limited. The aim of this study was to identify the presence of E. coli and investigate its antimicrobial resistance profiles throughout the entire tilapia production chain.MethodsA total of 240 samples were collected from various points in the production process: carcasses before scaling (Ca), scaling wastewater (Sw), filleting wastewater (Fw), fillet washing wastewater (Tw), fillet handling surfaces (Su), and pre-packaged fillets (Pf). The samples were collected during 10 visits, each corresponding to animals from different farms. E. coli isolates were identified using MacConkey agar and biochemical tests. Phenotypic resistance profiles were determined using nine classes of antimicrobials. Extended- spectrum b-lactamase (ESBL) production was identified with ceftazidime and cefotaxime and confirmed by a double-disc synergy test. Isolates were classified as sensitive or resistant based on the inhibition zone. Multidrug-resistant (MDR) was defined as resistance to at least one agent in three or more antimicrobial categories, while extensively drug-resistant (XDR) was defined as resistance to at least one agent in all but two or fewer categories.ResultsOverall, 50.8% of the samples (122/240) tested positive for E. coli, with 403 isolates identified. Of these, 33% (133/403) were resistant to at least two antimicrobials, and 20% (48/240) of the samples had MDR isolates, with the highest frequency found at the filleting point (Fw), which also had the only XDR profile. Resistance was most commonly observed against amoxicillin (35.73%), tetracycline (30.77%), and ciprofloxacin (26.30%).DiscussionThese findings emphasize the importance of E. coli as an indicator of antimicrobial resistance throughout tilapia processing and highlight the need for good production practices and qualified technical support to mitigate risks to public health, animal health, and the environment.

Combining Activated Carbon Adsorption and CO2 Carbonation to Treat Fly Ash Washing Wastewater and Recover High-Purity Calcium Carbonate

Fly ash washing wastewater was carbonated with carbon dioxide (CO2) to remove calcium (Ca) by forming a calcium carbonate (CaCO3) precipitate. An investigation of the factors affecting carbonation showed that Ca removal was highly dependent on the initial pH of the wastewater. The Ca removal was 10%, 61%, 91% and more than 99% at initial wastewater pH levels of 11.8, 12.0, 12.5 and 13.0, respectively. The optimal conditions for carbonation were initial pH of 13.0, carbonation time of 30 min and CO2 flow rate of 30 mL/min. The Ca concentration in the wastewater decreased to <40 mg/L, while 73 g of CaCO3 precipitate was produced per liter of wastewater. However, heavy metals, specifically Pb and Zn, co-precipitated during carbonation, which resulted in a CaCO3 product that contained as much as 0.61 wt% of Pb and 0.02 wt% of Zn. Activated carbon modified by a quaternary ammonium salt was used to selectively adsorb the Pb and Zn first. The Pb- and Zn-free water was then carbonated. By combining adsorption with carbonation, the Ca concentration in the treated wastewater was decreased to about 28 mg/L, while the Na, Cl and K were retained. The wastewater thus treated was ready for NaCl and KCl recovery. In addition, the precipitate had a Ca content of more than 38 wt% and almost no heavy metals. The average particle size of the precipitate was 47 μm, with a uniform cubic shape. The quality of the precipitate met the requirements for the industrial reuse of CaCO3. In summary, adsorption and carbonation combined were able to remove pollutants from wastewater while recovering useful resources.

Hydrodynamic Cavitation as a Method of Removing Surfactants from Real Carwash Wastewater.

The present work aimed to evaluate whether the use of an innovative method such as hydrodynamic cavitation (HC) is suitable for the simultaneous removal of surfactants of different chemical natures (non-ionic, anionic and cationic) from actual car wash wastewater at different numbers of passes through the cavitation zone and different inlet pressures. An additional novelty was the use of multi-criteria decision support, which enabled the selection of optimal HC conditions that maximized the removal of each group of surfactants and chemical oxygen demand (COD) with minimal energy input. For the optimal HC variants, Fourier transform infrared spectroscopy (FT-IR/ATR) as well as investigations of surface tension, zeta potential, specific conductivity, system viscosity and particle size were carried out. The highest reduction of non-ionic surfactants was found at 5 bar inlet pressure and reached 35.5% after 120 min. The most favourable inlet pressure for the removal of anionic surfactants was 3 bar and the removal efficiency was 77.2% after 120 min, whereas the most favourable inlet pressure for cationic surfactant removal was 3 bar, with the highest removal of 20% after 120 min. The obtained results clearly demonstrate that HC may constitute an effective, fast and cost-efficient method for removing surfactants from real industrial wastewater.

Application of Polymeric Tubular Ultrafiltration Membranes for Separation of Car Wash Wastewater.

The commercial ultrafiltration tubular polyvinylidene fluoride (PVDF) (100 and 200 kDa) and polyethersulfone (PES) (4 kDa) membranes were applied for filtration of car wash wastewater. Intensive fouling was noticed, which caused an over 50% flux reduction during 3-5 h of the filtration process. This phenomenon was reduced by washing the membranes with an alkaline cleaning agent (pH = 11.5), which is used in car washes to remove insects. The filtration/membrane washing cycle was repeated many times to achieve stable operation of the membrane modules. It has been found that cyclic repeated washing did not deteriorate the performance of the membranes. Despite frequent cleaning of the membranes (every 5-7 h), irreversible fouling occurred, resulting in a 20% reduction in the initial permeate flux. However, the formation of a filter cake definitely improved the separation degree and, for the 200 kDa membranes, separation of the wastewater components was obtained as it was for the 4 kDa membranes, while, at the same time, the permeate flux was 5 times higher.

Application of the sono-Fenton/UV process on the treatment of table olive processing wastewater

AbstractThe Mediterranean Basin economies of Spain, Italy, Greece, and Turkey depend on the table olive and olive oil industries. Table olive processing wastewater characteristics and quantity depend on olive varietal and processing methods. Olives and processing methods provide phenol, suspended particles, dissolved inorganic solids, and refractory organics. Due of its complexity, conventional methods struggle to tackle table olive processing wastewater. A novel approach to enhanced oxidation processes integrates many ways to boost hydroxyl radical formation and scale up efficiency. UV assisted sono-Fenton process as a modified Fenton process was applied to table olive washing wastewater to achieve high formation of hydroxyl radicals. When UV assisted sono-Fenton experiments executed to determine the optimum reaction conditions, the effects of hydrogen peroxide, ferrous ion concentrations and reaction time on the oxidation of table olive washing wastewater investigated by using a statistical experimental design. Chemical oxygen demand (COD), total organic carbon (TOC) and phenol removal efficiencies were examined by keeping the pH constant. The UV assisted sono-Fenton process achieved 53% phenol, 68% TOC, and 80% COD removal efficiencies. The results show that the UV assisted sono-Fenton process can treat effectively table olive processing wastewater. Optimum reaction conditions for the UV assisted sono-Fenton process were determined. UV assisted sono-Fenton process provides a significant reduction in reaction time and minimizes the costs of process associated with low chemical requirements. So, these optimum reaction conditions were resulted in low sludge production at the UV assisted sono-Fenton process while treating table olive processing wastewater.

Electrochemical nitrogen removal from ethylene washing wastewater

Electrochemical nitrogen removal from ethylene washing wastewater

Cleaning of Ultrafiltration Membranes: Long-Term Treatment of Car Wash Wastewater as a Case Study.

Car wash wastewaters (CWWs) contain various pollutants with different contents. Hence, selecting an appropriate process for their treatment is a great challenge. Undoubtedly, the ultrafiltration (UF) process is one of the most interesting and reliable choices. Therefore, the main aim of the current study was to investigate the performance of the UF membranes used for the long-term treatment of real CWWs. For this purpose, two polyethersulfone (PES) membranes with molecular weight cut-off (MWCO) values equal to 10 and 100 kDa were applied. As expected, a significant decrease in the permeate flux during the UF run was observed. However, it was immediately demonstrated that the systematic cleaning of membranes (every day) with Insect agent (pH = 11.5) prevented a further decline in the process's performance. In addition, this study focused on the relative flux during the process run with breaks lasting a few days when the UF installation was filled with distilled water. The results of this research indicated that aqueous media favor microorganism adherence to the surface which leads to the formation of biofilms inside processing installations. As a consequence, many attempts have been made to restore the initial membrane performance. It has been found that the application of several chemical agents is required. More precisely, the use of an Insect solution, P3 Ultrasil 11 agent, and phosphoric acid increases the relative flux to a value of 0.8. Finally, it has been indicated that the membranes used in this work are resistant to the long-term exposure to bacteria and chemical agents. However, during the separation of CWWs for the membrane with an MWCO of 10 kDa, a lesser fouling influence and higher effectiveness of cleaning were obtained. Finally, the present study demonstrates a novel analysis and innovative implications towards applying the UF process for the CWW treatment.

Bibliometric Insights into Car Wash Wastewater Treatment Research: Trends and Perspectives

Car wash wastewater (CWW) poses a significant environmental danger due to its high chemical oxygen demand (COD), heavy metals, and anionic surfactant complex composition, all of which can have an adverse effect on the environment. Even with the extensive research on CWW treatment, further study is necessary to improve our comprehension in this field. With an emphasis on CWW treatment processes and research trends, this study offers a comprehensive bibliometric analysis of 208 articles from the Scopus database. The analysis reveals that more than 55.77% of the research publications were released within the last five years, suggesting that there is increasing interest in the treatment of CWW. According to the data, the most important journal in this field is Desalination and Water Treatment. China and India were major research contributors. The main research directions in this area are properly indicated by the frequently used keywords “carwash wastewater”, “electrocoagulation”, “wastewater treatment”, and “water reuse”, according to an analysis of the keywords. Electrocoagulation, coagulation, and adsorption are common methods that are gaining popularity. In recent years, the most often researched CWW contaminants included those measured by COD and heavy metals. The results of this research offer an overview of recent developments.

The Effect of Adding Nutrients to Rice Washing Waste Water on Growth Results of Yellow Soybean Plant Microgreens (Glycine max (L.) Merill)

Soybeans contain many vitamins and minerals and are low in saturated fatty acids. Food ingredients derived from soybeans are also free from lactose, making them suitable for consumers who suffer from lactose intolerance. It is impossible to separate microgreens growth from their requirement for nutrients and water. Since microgreens are organic, chemical fertilizers are not used to them. Rice washing waste water is one substitute that can be utilized as fertilizer for microgreen plants. The purpose of this study is to ascertain the optimal concentration for maximizing the growth and yield of yellow soybean microgreens (Glycine max) and the impact of giving waste rice washing water on these microgreens. This study conducts quantitative research using an experimental design. A non-factorial randomized block design (RAK) was employed to collect the data, with concentration being the primary variable (P0: Control, P1: 50 ml rice washing water, P2: 100 ml rice washing water, P3: 150 ml rice washing water). Plant height, plant dry weight, plant wet weight, and chlorophyll levels are all significantly impacted by the availability of rice washing water, according to the research findings. The amount of leaves was unaffected by the presence of rice washing water. Plant height, dry weight, wet weight, and chlorophyll content can all be increased with P1 in as much as 50 milliliters of rice washing water.

Evaluation of the use of activated carbon derived from coconut shells to treat car wash wastewaters

Car wash services generate wastewater that consists of many contaminants. The discharge of raw car wash wastewater would bring adverse impacts to the environment. Therefore, this study aims to evaluate the use of activated carbon derived from coconut shells to treat car wash wastewater. In this study, activated carbon (AC) prepared from coconut shells shows a good microporosity structure with functional groups on the surface. The performance of activated carbon prepared is evaluated by determining the removal efficiency of the parameter including COD, BOD, and heavy metals concentration (zinc and iron) from car wash wastewater. The operating parameters are dosage (0.2 - 1.0 g/100 mL), contact time of 30 min-150 min and pH adjustment (pH 3 - pH 9). Throughout the research, the highest removal efficiencies of COD, BOD, zinc, and iron from automatic car wash wastewater are 91.03 %, 88.51 %, 68.25 %, and 86.09 % respectively achieved by 0.8 g of carbon dosage under 90 rpm agitation speed for 60 min. Under the same operational condition, CSAC removed 84.43 % COD, 81.80 % BOD, 59.78 % zinc, and 78.58 % iron from manual car wash wastewater. Therefore, the removal of pollutants from car wash water by using activated carbon derived from coconut shells has been proven to be an effective method.

Effects of Alkaline Cleaning Agents on the Long-Term Performance and Aging of Polyethersulfone Ultrafiltration Membranes Applied for Treatment of Car Wash Wastewater.

The commercial ultrafiltration polyethersulfone (PES) membranes (10 and 100 kDa) blended with polyvinylpyrrolidone (PVP) were applied for the filtration of car wash wastewater. Periodical membrane rinsing with water did not prevent fouling and a decrease in permeate flux was observed. Fouling was reduced by washing the membranes with cleaning agents, which are used in car washes to clean wheels and remove insects. In addition to surfactants, these agents contain NaOH, hence the pH value of cleaning solutions was over 11. Long-term contact with such solutions resulted in the removal of PVP from the membrane matrix and an increase in pore size. The PES membranes were soaked in an alkaline solution (pH = 11.5) for 20 months, after which the 200 kDa dextran rejection decreased from 95% to 80%. To compare with the static degradation conditions, 8 weeks of alkaline agent filtration was realized, after which the dextran (200 kDa) rejection decreased below 50%. This indicated that the cross-flow of alkaline agents can accelerate the removal of components building the membrane matrix. Despite membrane degradation, the separation efficiency (the rejection of chemical oxygen demand-COD, turbidity, and surfactants) during the treatment of synthetic car wash wastewater was similar to that obtained for pristine membranes.

Eco-friendly efficient cleaning of oiled sand by phosphorylated cellulose nanocrystal-based composite

Oil from offshore oil spills may be stranded on beaches and exist for decades, requiring appropriate cleaning agents to adequately remove it. Herein, a phosphorylated cellulose nanocrystals (PCNCs) −Tween80 composite cleaning agent was developed by adding trace amounts of nonionic surfactant Tween80. Through the synergistic interaction of various components, the cleaning agent exhibited high oil removal efficiencies for the oiled sand at 25 ℃ and sea salt concentration of 3.5 wt%. The difference among the oil removal efficiencies of cleaning agents containing different components was mainly attributed to variations in the interfacial tension and the zeta potential. The oil removal efficiencies of the cleaning agent for contaminated sand containing engine oil were 81.2 % and 91.4 % at the cleaning speeds of 150 rpm and 300 rpm, respectively. Surprisingly, the composite cleaning agent reached an oil removal efficiency of 89.9 % at just 150 rpm for the real-world polluted system of the sand contaminated with crude oil. At a relatively mild cleaning speed of 150 rpm, the cleaning effect exceeded those reported in most previous studies at 300 rpm. Furthermore, the washing wastewater achieved rapid and efficient oil/water separation under flocculation of using polyaluminum chloride, which was expected to significantly reduce the discharge of wastewater and avoid secondary pollution. This work has developed a PCNCs-based cleaning agent with advantages of high efficiency, environment-friendliness, convenient preparation, low cost, and low discharge of wastewater, which can efficiently remove oil from oiled sand.

Self-assembly formation of Co quantum dot loaded N-doped porous carbon cathode for quinoline degradation in the electro-Fenton system

Quinoline is high toxicity and difficult biodegradation in oil washing wastewater. Therefore, efficient removal of quinoline contaminant from water bodies poses a major challenge. Hence, Co quantum dot loaded N-doped porous carbon (CoNC) nanosheets grown in situ on carbon cloth were fabricated as cathode for the degradation of quinoline in electro-Fenton system. Under optimal conditions (c(Fe2+) = 0.5 mM, U = -0.3 V, pH = 3), quinoline was completely degraded within 15 min with superior apparent rate constant of 0.385 min−1, which was 19.6 times higher than that of the ZIF-L precursor, due to the abundance of Co QDs active sites and hydrophilicity and electrical conductivity of N-doped porous carbon. In addition, three reaction pathways for quinoline were deduced by combining Density Functional Theory (DFT) calculation and Liquid Chromatography-Mass Spectrometry (LC-MS). More importantly, in situ FTIR and free energy calculations were analyzed to reveal that pathway Ⅰ as spontaneous reaction was the main reaction pathway. Finally, the toxicity of the intermediates was assessed with ECOSAR software and E. coli experiments, and the overall toxicity decreased during the degradation reactions. This work provides novel perspectives on environmental protection by designing in-situ grown cathodes through self-assembly method, thereby effectively purifying pollutants from wastewater.

Influence of Type and Dose of Coagulants on Vehicle Wash Wastewater

The study was conducted to investigate the effect of the type and dosage of coagulant on changes in phosphate and fatty oil levels in liquid waste from motor vehicle wash. The independent variables in this study were the type of coagulant (Al2(SO4)3 and FeCl3) and the dosage of coagulant (0 ml, 3 ml, 5 ml, and 7 ml), while the dependent variables were the content of phosphate and fatty oil. The experiment was conducted in 3 stages; fast stirring, slow stirring, and precipitation. From the preliminary test, it was found that the phosphate content before processing was 12.9 mg/lt and the content of fatty oil was 1.9 mg/lt. The most significant decrease in phosphate content was found when 7 ml of FeCl3 was used as coagulant; it dropped to 0.11 mg/lt (efficiency: 99.2%). Meanwhile, the most effective coagulant for fatty oil was 3 ml of Al2(SO4)3; the fatty oil content dropped to 1.4 mg/lt (efficiency: 30.7%). The addition of Al2(SO4)3 gave the opposite effect on phosphate and fatty oil, making the process ineffective. Meanwhile, the data showed that FeCl3 could be used as an effective coagulant for phosphate and fatty oil. To determine the significance of the differences between the results of the Randomized Complete Block Design analysis, the researcher used Least Significant Design test. The results showed that the variation of the type of coagulant affected the decrease in phosphate and fatty oil levels, while the variation in dosage gave no significant difference.

Pengolahan Limbah Cair Laundry Menggunakan Membran Ultrafiltrasi Aliran Cross Flow dengan Variasi Tekanan Transmembran dan Konsentrasi Chemical Cleaning Agent (NaOH)

Ultrafiltration membrane is one of wastewater treatment technologies, but membranes have limitations such as the occurrence of the phenomenon of concentration polarization and fouling. The research objective of this study the effect of variations in transmembrane pressure against the rejection percentage COD, TSS, and the effect of variations in transmembrane pressure, concentration of washing of the efficiency and effectiveness of washing the membrane. The process of ultrafiltration membranes and membrane chemical washing wastewater laundry do with variations in pressure of 1 bar, 2 bar, and 3 bar. Variation of chemical cleaning agent concentration of 1%, 1.5% and 2%, rinsing with distilled water for 30 minutes, filtering wastewater laundry for 120 minutes, and washing using chemical cleaning agent (NaOH) for 30 minutes. Highest rejection percentage for COD parameter 86.6% and 85.7% for TSS parameters in transmembrane pressure of 3 bar. The highest washing efficiency of the value of Flux Recovery (FR) gained 81.9%, and the value of resistance of Removal (RR) gained 82.59% with a concentration of 2% in the transmembrane pressure of 3 bar. The highest leaching effectiveness obtained at 50.21% with a concentration of 2% and a transmembrane pressure of 3 bar.

Denim washing wastewater treatment by coupling coagulation–flocculation/Fe-garnet filtration: life cycle assessment and the fertilization with the sludge

Denim washing wastewater treatment by coupling coagulation–flocculation/Fe-garnet filtration: life cycle assessment and the fertilization with the sludge

The Resistance of Polyethersulfone Membranes on the Alkaline Cleaning Solutions.

Polyethersulfone (PES) is a polymer popularly used to produce ultrafiltration (UF) membranes. PES is relatively hydrophobic; thus, hydrophilic ingredients are added to the membrane matrix to reduce the fouling intensity. Ingredients such as polyvinylpyrrolidone (PVP) reduce the resistance of PES to NaOH solutions. This study investigated the possibility of using PES membranes for the separation of alkaline cleaning solutions. For this purpose, self-made PES membranes and commercial ultrafiltration PES membranes (UE10-10 kDa and UE50-100 kDa) containing PVP additive were used. The membranes were soaked for 18 months in alkaline (pH = 11.3-11.5) solutions of car washing fluids. It has been found that long-term contact with these solutions caused changes in the structure of the surface layer, especially of membranes containing PVP. As a result, the separation of dextran (100-200 kDa) decreased by 30-40% for PES membranes, 30-40% for UE10 and 40-60% for UE50. Despite these changes, the separation efficiency (rejection of COD, NTU and anionic surfactants) of synthetic car wash wastewater (mixture of surfactants and hydrowax) was similar to the results obtained for pristine membranes.

Features of using bentonite clay of the Darbazа deposit for wastewater treatment of petrochemical productions

This article applies the method of sorption treatment of wastewater from petrochemical production with a sorbent based on bentonite clay from the Darbazа deposit.In connection with the increase in consumption and discharge of wastewater by industrial facilities in our country, the issue of purification of emissions, wastewater, and the introduction of closed production cycles are the main methods of improving environmental quality. One of the largest industrial enterprises, during the operation of which washing wastewater is generated, is the largest oil refinery (PetroKazakhstanOilProducts), located in Shymkent, as well as petrochemical industry enterprises. Some of the largest industrial enterprises are the oil refining and petrochemical industries. As is known, enterprises in this industry have a negative impact on the environmental situation in many regions of Kazakhstan, polluting the air, water bodies, and soil. The results obtained during the experiment proved the effectiveness of the sorbent in relation to chemical oxygen demand and petroleum products in the analyzed solutions. To carry out the sorption process, bentonite clay, which was selected as a sorbent material, was subjected to chemical activation using sodium salts. Based on the results obtained, we can conclude that the purification efficiency for activated bentonite with NaCl in terms of chemical oxygen demand is 82.85%, for petroleum products - 89.45%, and the purification efficiency for activated bentonite with Na2 CO3 reaches 85.41% for chemical oxygen demand, for petroleum products - 89.78%.

Research and Application of Zero-Discharge Treatment Technology for Coal Mine Washing Wastewater

Research and Application of Zero-Discharge Treatment Technology for Coal Mine Washing Wastewater