Industrial Water Treatment Research Articles

All-fiber impurity collector based on laser-induced microbubble

Microbubbles have attracted interests in polluted water treatment industry. We proposed and constructed an all-fiber impurity collector based on the laser-induced microbubbles characteristics for polluted water treatment. Without any special pretreatment, such as metallically coating or carbon materials doping, the proposed impurity collector performed microbubbles generation and impurities extraction and collection. We employed the graphite oxide nanoplatelets in an aqueous solution to construct the polluted water environment to show the performance of the all-fiber impurity collector. With the optimal incident laser power of 11 mW, we performed the collection efficiency as high as 16.3×104 /s. The optimal microbubbles diameter was in the range of 80–120 μm. The proposed all-fiber impurity collector extends the potential applications of fiber-based optical manipulation for polluted water treatment.

Эффективность применения коагулянтов при водоподготовке в целлюлозно-бумажной промышлен- ности в условиях Севера

Эффективность применения коагулянтов при водоподготовке в целлюлозно-бумажной промышлен- ности в условиях Севера

Design of Facultative Pond for the Treatment of Industrial Waste Water in Urban Settlement

This study evaluated the degree of pollution of Ikpoba River due to the incessant discharge of industrial wastewater into the river. The entire study area was digitised and geo-referenced in order to generate the map of the study area as well as the sampling points. Eight (8) water samples were obtained from different locations from the direction of flow of industrial discharge into the river and also within the river. The coordinate of the sample collection points were acquired using handheld geographic positioning system (GPS). Water samples for physicochemical analysis were collected in a clean sterilized plastic container and analysis were carried out in the laboratory following standard procedure. The environmental variables measured were dissolved oxygen (DO), total suspended solid (TSS), pH, total dissolved solid (TDS), turbidity, concentration of nitrate and nitrite, chloride, phosphate, zinc, barium, tin, biological oxygen demand (BOD), conductivity, manganese, magnesium, calcium etc. Results obtained showed that most parameters investigated had increasing values. The calculated water quality index (WQI) from the sampling points ranged from 40.02 to 52.62, which indicates that most of the samples are bad as classified using National Sanitation Foundation (NSF) standard. This study therefore recommends that water quality around areas of industrial wastewater discharge in Ikpoba hill should be monitored and adequate treatment recommended where necessary.

Micro-/Nanoscale Approach for Studying Scale Formation and Developing Scale-Resistant Surfaces.

Blockage of pipelines due to accretion of salt particles is detrimental in desalination and water-harvesting industries as they compromise productivity, while increasing maintenance costs. We present a micro-/nanoscale approach to study fundamentals of scale formation, deposition, and adhesion to engineered surfaces with a wide range of surface energies fabricated using the initiated chemical vapor deposition method. Silicon wafers and steel substrates are coated with poly(1 H,1 H,2 H,2 H-perfluorodecylacrylate) or pPFDA, poly(tetravinyl-tetramethylcyclotetrasilohexane) or pV4D4, poly(divinylbenzene) or pDVB, poly(1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasilohexane) or pV3D3, and cross-linked copolymers of poly(2-hydroxyethylmethacrylate) and poly(ethylene glycol) diacrylate or p(PHEMA- co-EGDA). Particles of salt (CaSO4·2H2O) are formed and shaped with a focused ion beam and adhered to a tipless cantilever beam using a micromanipulator setup to study their adhesion strength with a molecular force probe (MFP). Adhesion forces were measured on the substrates in wet and dry conditions to evaluate the effects of interfacial fluid layers and capillary bridges on net adhesion strength. The adhesion between salt particles and the pPFDA coatings decreased by 5.1 ± 1.15 nN in wet states, indicating the influence of capillary bridging between the particle and the liquid layer. In addition, scale nucleation and growth on various surfaces is examined using a quartz crystal microbalance (QCM), where supersaturated solution of CaSO4·2H2O is passed over bare and polymer-coated quartz substrates while mass gain is measured in real time. The salt accretion decreased by 2 folds on pPFDA-coated substrates when compared to that on p(HEMA- co-EGDA) coatings. Both MFP and QCM studies are essential in studying the impact of surface energy and roughness on the extent of scale formation and adhesion strength. This study can pave way for the design of scale-resistant surfaces with potential applications in water treatment, energy harvesting, and purification industries.

Assembly of graphene-coated nickel nanowires and their catalytic performance

ABSTRACTThe investigation on the catalysts for reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) with NaBH4 have captured intensive interest. Nevertheless, the materials with low expenditure and outstanding catalytic performances are difficult to obtain. Herein, a simple and efficient strategy, which was assisted with external magnetic field, had been proposed for preparation of graphene-coated nickel nanowires (NiNWs/G) nanocomposite magnetic catalyst. The whole fabrication procedure was facile without harsh preparation conditions like high-pressure, high-temperature, strong acid and expensive templates. The NiNWs/G could be easily and quickly prepared in aqueous solution under mild conditions, and the external magnetic force was adopted to induce the unidirectional self-assembly of metal crystals on graphene oxide to form NiNWs/G with aspect ratio more than 50. The possible formation mechanism suggesting that the nanoparticles would aggregate along with direction of the magnetization axis because the dipole magnetic moments of them are in line under magnetic induction lines. The characterization results confirmed the chemical component and morphology of the nanocomposite. The ferromagnetism is determined by hysteresis loop of NiNWs/G. More importantly, the nanocomposite exhibited superior catalytic performance toward reduction of 4-nitrophenol. Therefore, such nanocomposite will be a promising candidate for water treatment and catalyst industry.

Optimization of Maintenance Management of Industrial Water Heat Exchangers and Water Treatment

Optimization of Maintenance Management of Industrial Water Heat Exchangers and Water Treatment

Synthesis and characterization of polyethersulfone membranes impregnated with (3-aminopropyltriethoxysilane) APTES-Fe3O4 nanoparticles for As(V) removal from water

Polyethersulfone (PES) nanocomposite membranes are synthesized with surface modified Fe3O4 nanoparticles (NPs) for removing arsenic from water. The PES membranes synthesized with A-Fe3O4 NPs exhibited efficient adsorption capacity with a low concentration of NPs (1 wt%, 2 wt%, 3 wt%), which indicate a good potential for industrial applications in water treatment industries. The highest rejection rate of 76% and the highest measured arsenic equilibrium adsorption capacity of 14.6 mg/g were measured in PES membranes containing 3 wt% A-Fe3O4 NPs.Infrared spectroscopy (IR) was used to verify the surface modification of Fe3O4 NPs. Thermogravimetric Analysis (TGA) was used to evaluate the dispersion of the modified Fe3O4 NPs in the PES membrane matrix. Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscopy (AFM) were used to characterize the pore structure and surface roughness of PES membranes containing APTES modified Iron Oxide nanoparticles (A-Fe3O4 NPs). Highest porous structure was found in PES-A-Fe3O4 3 wt% and roughness was increased with addition of A-Fe3O4 NPs (0,1,2 wt.%). Pore size analysis was conducted using water flux method. Hydrophilicity was characterized with measuring the water contact angle and pure water flux was measured using a pressurized membrane cell. Langmuir and Freundlich isotherm models were analyzed using batch adsorption tests.

Study of various organophosphonate additives as calcium carbonate inhibitors for reverse osmosis

Various chemical additives are used in water treatment industry, among them – precipitation inhibitors for reverse osmosis membrane facilities. The development and synthesis of new inhibitor formulas and the study of their effectiveness is still an urgent task for many researchers working in this field. The relationship between the structure of phosphonate scale inhibitors and their effectiveness in preventing of calcium carbonate precipitation was studied. Two classes of tetraphosphonate and diphosphonate inhibitors that possess systematic structural similarities and differences have been tested on the laboratory membrane unit. All chemicals were tested at doses of 1 and 5 mg/L. The results showed that the antiscalant efficiency for both groups of inhibitors increases with elongation of methylene chain, but the longest compounds have a sharp drop in inhibition efficiency.

Review on Denitrification Technologies of Landfill Leachate

The disposal of landfill leachate is a difficult problem in today’s water treatment industry. The landfill leachate contains high concentrations of ammonia nitrogen, which not only increases the difficulty of biological treatment, but also wastes a lot of ammonia energy. This paper reviews the current denitrification methods commonly used in landfill leachate, analyzes their advantages and disadvantages, and proposes the future development direction.

Polyethyleneimine-Capped Silver Nanoparticles as Antifouling Photocatalyst for Wastewater Treatment

Abstract Water pollution is one of the most urgent challenges of the 21st century, with water security having widespread consequences on society and the global economy. Methylene blue (MB) is a toxic by-product of textile and dye industries which has polluted wastewaters. Biofouling of man-made surfaces is a longstanding issue with serious consequences in the maritime and water treatment industries. Ag and its compounds are historically well-known as antibacterial agents, whilst polyethyleneimine (PEI) has good stabilizing and adsorption properties. In this work, colloidal Ag nanomaterials (diameter ∼2.6 ± 1.1 nm) produced using PEI as the capping agent demonstrated potential as antifouling photocatalysts for water treatment applications. The photocatalytic effect of Ag-PEI was studied using UV-visible spectrophotometry on the decomposition of methylene blue, with a 90.2% peak reduction of its UV-visible spectral peaks and decoloration recorded after 90 minutes of UV-irradiation. Separately, Ag-PEI demonstrated a 63% reduction of biofilm formation by Halomonas pacifica, a model marine-biofilm bacterium, through a static biofilm assay.

Современные методы флуоресцентного контроля в промышленной водоподготовке

Современные методы флуоресцентного контроля в промышленной водоподготовке

Characteristics of Electrochemical Electrodes Containing Composite Films of Boron-doped Nanocrystalline Diamond and Amorphous Carbon Prepared using a Coaxial arc Plasma Deposition Method

Composite films of boron-doped nanocrystalline diamond and amorphous carbon (B-doped NCD/a-C) were prepared using a coaxial arc plasma deposition (CAPD) method at an unheated substrate temperature without using any reaction gases. Cyclic voltammetry (CV) measurements of the deposited films showed that they exhibit the unique electrochemical characteristics of diamond crystallites. The 4-nitrophenol (4-NP) aqueous solution, which is a recalcitrant substance found in industrial effluents, was degraded via electrolytic treatment using a batch-type system wherein the deposited films were used as anodes. UV–vis measurements revealed that part of the molecular structure of the 4-NP changed during this reaction. Furthermore, the total organic carbon (TOC) content in the 4-NP aqueous solution decreased as the electrolytic reaction progressed, implying that the degradation of 4-NP proceeded to yield CO2. The results reveal that the B-doped NCD/a-C films prepared using CAPD can be used as high-performance electrochemical electrode materials in industrial water treatment.

Kinetic Study of Oxidation of Nitrophenol Present in Waste Water using Ferrous Sulphate

Abstract The detoxification of wastewater containing nitro aromatic compounds is very difficult due to its resistance to oxidation. Therefore, it becomes important for the chemical industries to apply an efficient pre-treatment method to reduce the level of these compounds. In this study, Fenton oxidation treatment of industrial waste water containing nitro-phenol with Ferrous Sulphate is reported. Kinetic study of de-colorization and degradation reactions in terms of the effect of doses of Fe2+ H2O2 and contact time is studied. The maximum COD, total organic carbon and colour removal efficiency is found to be 93%, 80% and 99%, respectively in 2 h at 132.3 mM H2O2 concentration and 10.74 mM Fe2+ dose.

Биологическая очистка производственных сточных вод

Биологическая очистка производственных сточных вод

Comparative study on mechanical behavior of ASS 316L for low and high temperature applications

Abstract Austenitic Stainless-Steel 316L is among the significant ASS grades which are most commonly used in various modern industries. It has greater resistance to corrosion in the ordinary atmosphere as well as in extreme environments such as salt water and environments where resistance to pitting and chloride corrosion is required. While performing well when exposed to elevated temperatures, it can also maintain its quality toughness and strength at negative temperatures which makes it as an exceptional choice for applications such as water treatment, marine, nuclear, aerospace and automobile industries. Therefore, present study focused on evaluating and comparing the mechanical properties namely ultimate tensile strength (UTS), 0.2% of yield quality (YS) and percentage elongation from the experimental data acquired from the uniaxial isothermal tensile tests performed at sub-zero temperatures (0 °C, −25 °C & −50 °C) with a range of cross head speeds and at elevated temperatures (750 °C, 825 °C & 900 °C) in three orientations (0, 45, 90) degrees to the rolling direction. The influence of temperature and strain rate on the responses has been resolved and the comparison has been made at extreme temperatures.

Preparation of thin film composite membranes using interfacial polymerization for treatment of industrial water containing heavy metals

Preparation of thin film composite membranes using interfacial polymerization for treatment of industrial water containing heavy metals

Data Mining Application in Assessment of Weather-Based Influent Scenarios for a WWTP: Getting the Most Out of Plant Historical Data

Since the introduction of environmental legislations and directives, the impact of combined sewer overflows (CSO) on receiving water bodies has become a priority concern in water and wastewater treatment industry. Time-consuming and expensive local sampling and monitoring campaigns are usually carried out to estimate the characteristic flow and pollutant concentrations of CSO water. This study focuses on estimating the frequency and duration of wet-weather events and their impacts on influent flow and wastewater characteristics of the largest Italian wastewater treatment plant (WWTP) located in Castiglione Torinese. Eight years (viz. 2009–2016) of historical data in addition to arithmetic mean daily precipitation rates (PI) of the plant catchment area are elaborated. Relationships between PI and volumetric influent flow rate (Qin), chemical oxygen demand (COD), ammonium (N-NH4), and total suspended solids (TSS) are investigated. A time series data mining (TSDM) method is implemented with MATLAB computing package for segmentation of time series by use of a sliding window algorithm (SWA) to partition the available records associated with wet and dry weather events. According to the TSDM results, a case-specific wet-weather definition is proposed for the Castiglione Torinese WWTP. Two significant weather-based influent scenarios are assessed by kernel density estimation. The results confirm that the method suggested within this study based on plant routinely collected data can be used for planning the emergency response and long-term preparedness for extreme climate conditions in a WWTP. Implementing the obtained results in dynamic process simulation models can improve the plant operational efficiency in managing the fluctuating loads.

Genetic Algorithm–Genetic Programming Approach to Identify Hierarchical Models for Ultraviolet Disinfection Reactors

AbstractThe performance of ultraviolet (UV) disinfection reactors using experimental data poses major challenges to the water treatment industry, and a regression model has been developed in the wa...

Structural, optical and photocatlytic properties of zinc oxide nanoparticles obtained by simple plant extract mediated synthesis

We report a facile and inexpensive method to prepare zinc oxide nanoparticles with different particle size and shape using Achyranthes aspera and Couroupita guianensis leaf extracts as the reducing agent and zinc nitrate as a precursor. The prepared zinc oxide nanoparticles were analyzed by various characterization methods and obtained results evidently revealed that crystalline parameter, purity, optical absorption, band gap, particle size and shape of the ZnO nanoparticles significantly influenced by the type of leaf extract used as reducing agent. Further, photocatlytic activity study obviously demonstrates that prepared samples exhibits superior photocatlytic activity for the degradation of methylene blue dye by creating superoxide anion radicals and OH radicals under photonic irradiation. Hence, prepared zinc oxide nanoparticles by plant extract mediated synthesis can be applied as a photocatlyst for the possible waste water treatment in textile industry.

Genome-resolved metagenomic analysis reveals roles of microbial community members in full-scale seawater reverse osmosis plant

Biofouling of Reverse Osmosis (RO) membrane is a significant issue for the water treatment industry. In this study, we apply the metagenomic shot-gun sequencing technology to characterise the composition and functional potential of the microbial community in a full-scale RO plant, at different stages of seawater treatment. We find Proteobacteria, Bacteroidetes and Planctomycetes to be the most abundant bacterial phyla. The genetic potential of the RO membrane microbial community shows the enrichment of genes involved in biofilm formation, representing the selective pressure of the biofilm formation process. We recover 31 metagenome-assembled genomes (MAGs) from intake (raw seawater), fouled RO membranes (leading and middle RO module) and brine reject water. A total of 25 MAGs are recovered from the biofilm samples (leading and middle RO modules), with 9 of them (36%) belonging to Planctomycetes. We investigate all 25 MAGs for genes (pili, flagella, quorum sensing, quorum quenching and nitrate reduction) that play an important role in biofilm formation and sustenance of cells. We show that Planctomycetes contain genes for the formation of flagella and pili, and the reduction of nitrate. Although genes for quorum sensing are not detected, quorum quenching genes are identified in the biofilm MAGs. Our results show that Planctomycetes, along with other microbes, play an important role in the formation and sustenance of biofilms on seawater RO membranes.