Search results for: water oxidation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9240

Search results for: water oxidation

7890 Data Analysis Tool for Predicting Water Scarcity in Industry

Authors: Tassadit Issaadi Hamitouche, Nicolas Gillard, Jean Petit, Valerie Lavaste, Celine Mayousse

Abstract:

Water is a fundamental resource for the industry. It is taken from the environment either from municipal distribution networks or from various natural water sources such as the sea, ocean, rivers, aquifers, etc. Once used, water is discharged into the environment, reprocessed at the plant or treatment plants. These withdrawals and discharges have a direct impact on natural water resources. These impacts can apply to the quantity of water available, the quality of the water used, or to impacts that are more complex to measure and less direct, such as the health of the population downstream from the watercourse, for example. Based on the analysis of data (meteorological, river characteristics, physicochemical substances), we wish to predict water stress episodes and anticipate prefectoral decrees, which can impact the performance of plants and propose improvement solutions, help industrialists in their choice of location for a new plant, visualize possible interactions between companies to optimize exchanges and encourage the pooling of water treatment solutions, and set up circular economies around the issue of water. The development of a system for the collection, processing, and use of data related to water resources requires the functional constraints specific to the latter to be made explicit. Thus the system will have to be able to store a large amount of data from sensors (which is the main type of data in plants and their environment). In addition, manufacturers need to have 'near-real-time' processing of information in order to be able to make the best decisions (to be rapidly notified of an event that would have a significant impact on water resources). Finally, the visualization of data must be adapted to its temporal and geographical dimensions. In this study, we set up an infrastructure centered on the TICK application stack (for Telegraf, InfluxDB, Chronograf, and Kapacitor), which is a set of loosely coupled but tightly integrated open source projects designed to manage huge amounts of time-stamped information. The software architecture is coupled with the cross-industry standard process for data mining (CRISP-DM) data mining methodology. The robust architecture and the methodology used have demonstrated their effectiveness on the study case of learning the level of a river with a 7-day horizon. The management of water and the activities within the plants -which depend on this resource- should be considerably improved thanks, on the one hand, to the learning that allows the anticipation of periods of water stress, and on the other hand, to the information system that is able to warn decision-makers with alerts created from the formalization of prefectoral decrees.

Keywords: data mining, industry, machine Learning, shortage, water resources

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7889 Drought Detection and Water Stress Impact on Vegetation Cover Sustainability Using Radar Data

Authors: E. Farg, M. M. El-Sharkawy, M. S. Mostafa, S. M. Arafat

Abstract:

Mapping water stress provides important baseline data for sustainable agriculture. Recent developments in the new Sentinel-1 data which allow the acquisition of high resolution images and varied polarization capabilities. This study was conducted to detect and quantify vegetation water content from canopy backscatter for extracting spatial information to encourage drought mapping activities throughout new reclaimed sandy soils in western Nile delta, Egypt. The performance of radar imagery in agriculture strongly depends on the sensor polarization capability. The dual mode capabilities of Sentinel-1 improve the ability to detect water stress and the backscatter from the structure components improves the identification and separation of vegetation types with various canopy structures from other features. The fieldwork data allowed identifying of water stress zones based on land cover structure; those classes were used for producing harmonious water stress map. The used analysis techniques and results show high capability of active sensors data in water stress mapping and monitoring especially when integrated with multi-spectral medium resolution images. Also sub soil drip irrigation systems cropped areas have lower drought and water stress than center pivot sprinkler irrigation systems. That refers to high level of evaporation from soil surface in initial growth stages. Results show that high relationship between vegetation indices such as Normalized Difference Vegetation Index NDVI the observed radar backscattering. In addition to observational evidence showed that the radar backscatter is highly sensitive to vegetation water stress, and essentially potential to monitor and detect vegetative cover drought.

Keywords: canopy backscatter, drought, polarization, NDVI

Procedia PDF Downloads 142
7888 Eucalyptus camendulensis and Its Drying Effect on Water and Essential Oil Content

Authors: Mehani Mouna, Segni Ladjel

Abstract:

Medicinal and aromatic plants are promising and are characterized by the biosynthesis of odorous molecules that make up the so-called essential oils (EO), which have long been known for their antiseptic and therapeutic activity in folk medicine. The objective of this study was to evaluate the influence of drying in the shade on the water content and on the content of essential oils extracted from leaves of Eucalyptus camendulensis for better quality control of medicinal and aromatic plants. The water content of the Eucalyptus camendulensis plant material decreases during the drying process. It increased from 100 % to 0.006 % for the drying in the shade after ten days. The moisture content is practically constant at the end of the drying period. The drying in the shade increases the concentration of essential oils of Eucalyptus camendulensis. When the leaves of Eucalyptus camendulensis plant are in the shade, the maximum of the essential oil content was obtained on the eighth days; the recorded value was 1.43% ± 0.01%. Beyond these periods, the content continuously drops in before stabilizing. The optimum drying time is between 6 and 9 days.

Keywords: Eucalyptus camendulensis, drying, essential oils, water, content

Procedia PDF Downloads 356
7887 Recovery from Detrimental pH Troughs in a Moorland River Using Monitored Calcium Carbonate Introductions

Authors: Lauren Dawson, Sean Comber, Richard Sandford, Alan Tappin, Bruce Stockley

Abstract:

The West Dart River is underperforming for Salmon (Salmo salar) survival rates due to acidified pH troughs under the European Water Framework Directive (2000/60/EC). These troughs have been identified as being caused by historic acid rain pollution which is being held in situ by peat bog presence at site and released during flushing events. Natural recovery has been deemed unlikely by the year 2020 using steady state water chemistry models and therefore a program of monitored calcium carbonate (CaCO3) introductions are being conducted to eliminate these troughs, which can drop to pH 2.93 (salmon survival – pH 5.5). The river should be naturally acidic (pH 5.5-6) due to the granite geology of Dartmoor and therefore the CaCO3 introductions are under new methodology (the encasing of the CaCO3 in permeable sacks) to ensure removal should the water pH rise above neutral levels. The water chemistry and ecology are undergoing comprehensive monitoring, including pH and turbidity levels, dissolved organic carbon and aluminum concentration and speciation, while the aquatic biota is being used to assess the potential water chemistry changes. While this project is ongoing, results from the preliminary field trial show only a temporary, localized increase in pH following CaCO3 introductions into the water column. However, changes to the water chemistry have only been identified in the West Dart after methodology adjustments to account for flow rates and spate-dissolution, though no long-term changes have so far been found in the ecology of the river. However, this is not necessarily a negative factor, as the aim of the study is to protect the current ecological communities and the natural pH of the river while remediating only the detrimental pH troughs.

Keywords: anthropogenic acidification recovery, calcium carbonate introductions, ecology monitoring, water chemistry monitoring

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7886 Reliability-Based Maintenance Management Methodology to Minimise Life Cycle Cost of Water Supply Networks

Authors: Mojtaba Mahmoodian, Joshua Phelan, Mehdi Shahparvari

Abstract:

With a large percentage of countries’ total infrastructure expenditure attributed to water network maintenance, it is essential to optimise maintenance strategies to rehabilitate or replace underground pipes before failure occurs. The aim of this paper is to provide water utility managers with a maintenance management approach for underground water pipes, subject to external loading and material corrosion, to give the lowest life cycle cost over a predetermined time period. This reliability-based maintenance management methodology details the optimal years for intervention, the ideal number of maintenance activities to perform before replacement and specifies feasible renewal options and intervention prioritisation to minimise the life cycle cost. The study was then extended to include feasible renewal methods by determining the structural condition index and potential for soil loss, then obtaining the failure impact rating to assist in prioritising pipe replacement. A case study on optimisation of maintenance plans for the Melbourne water pipe network is considered in this paper to evaluate the practicality of the proposed methodology. The results confirm that the suggested methodology can provide water utility managers with a reliable systematic approach to determining optimum maintenance plans for pipe networks.

Keywords: water pipe networks, maintenance management, reliability analysis, optimum maintenance plan

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7885 Enhancement of Dissolved Oxygen Concentration during the Electrocoagulation Process Using an Innovative Flow Column: Electrocoagulation Reactor

Authors: Khalid S. Hashim, Andy Shaw, Rafid Alkhaddar

Abstract:

Dissolved oxygen (DO) plays a key role in the electrocoagulation process (EC) as it oxidizes the heavy metals, ammonia, and cyanide into other forms that can be removed easily from water. Hence, many of the previous investigations used external aerators to provide the required DO inside EC reactors, especially when the water being treated had a low DO (such as leachate and high organic content waters), or when the DO depleted during the EC treatment. Although the external aeration process effectively enhances the DO concentration, it has a significant impact on energy consumption. Thus, the present project aims to fill a part of this gap in the literature by an innovative use of perforated flow columns in the design of an EC reactor (ECR1). In order to investigate the performance of ECR1, water samples with a controlled DO concentration were pumped at different flow rates (110, 220, and 440 ml/min) to the ECR1 for 10 min. The obtained results demonstrated that the ECR1 increased the DO concentration from 5.0 to 9.54, 10.53, and 11.0 mg/L, which is equivalent to 90.8%, 110.6%, and 120% at flow rates of 110, 220, and 440 mL/min respectively.

Keywords: flow column, electrocoagulation, dissolved oxygen, water treatment

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7884 Sustainable Manufacturing Industries and Energy-Water Nexus Approach

Authors: Shahbaz Abbas, Lin Han Chiang Hsieh

Abstract:

The significant population growth and climate change issues have contributed to the natural resources depletion and their sustainability in the future. Manufacturing industries have a substantial impact on every country’s economy, but the sustainability of the industrial resources is challenging, and the policymakers have been developing the possible solutions to manage the sustainability of industrial resources such as raw material, energy, water, and industrial supply chain. In order to address these challenges, nexus approach is one of the optimization and modelling techniques in the recent sustainable environmental research. The interactions between the nexus components acknowledge that all components are dependent upon each other, and they are interrelated; therefore, their sustainability is also associated with each other. In addition, the nexus concept does not only provide the resources sustainability but also environmental sustainability can be achieved through nexus approach by utilizing the industrial waste as a resource for the industrial processes. Based on energy-water nexus, this study has developed a resource-energy-water for the sugar industry to understand the interactions between sugarcane, energy, and water towards the sustainable sugar industry. In particular, the focus of the research is the Taiwanese sugar industry; however, the same approach can be adapted worldwide to optimize the sustainability of sugar industries. It has been concluded that there are significant interactions between sugarcane, energy consumption, and water consumption in the sugar industry to manage the scarcity of resources in the future. The interactions between sugarcane and energy also deliver a mechanism to reuse the sugar industrial waste as a source of energy, consequently validating industrial and environmental sustainability. The desired outcomes from the nexus can be achieved with the modifications in the policy and regulations of Taiwanese industrial sector.

Keywords: energy-water nexus, environmental sustainability, industrial sustainability, natural resource management

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7883 Performance of Partially Covered N Number of Photovoltaic Thermal (PVT) - Compound Parabolic Concentrator (CPC) Series Connected Water Heating System

Authors: Rohit Tripathi, Sumit Tiwari, G. N. Tiwari

Abstract:

In present study, an approach is adopted where photovoltaic thermal flat plate collector is integrated with compound parabolic concentrator. Analytical expression of temperature dependent electrical efficiency of N number of partially covered Photovoltaic Thermal (PVT) - Compound Parabolic Concentrator (CPC) water collector connected in series has been derived with the help of basic thermal energy balance equations. Analysis has been carried for winter weather condition at Delhi location, India. Energy and exergy performance of N - partially covered Photovoltaic Thermal (PVT) - Compound Parabolic Concentrator (CPC) Water collector system has been compared for two cases: (i) 25% area of water collector covered by PV module, (ii) 75% area of water collector covered by PV module. It is observed that case (i) has been best suited for thermal performance and case (ii) for electrical energy as well as overall exergy.

Keywords: compound parabolic concentrator, energy, photovoltaic thermal, temperature dependent electrical efficiency

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7882 The Thermochemical Conversion of Lactic Acid in Subcritical and Supercritical Water

Authors: Shyh-Ming Chern, Hung-Chi Tu

Abstract:

One way to utilize biomass is to thermochemically convert it into gases and chemicals. For conversion of biomass, glucose is a particularly popular model compound for cellulose, or more generally for biomass. The present study takes a different approach by employing lactic acid as the model compound for cellulose. Since lactic acid and glucose have identical elemental composition, they are expected to produce similar results as they go through the conversion process. In the current study, lactic acid was thermochemically converted to assess its reactivity and reaction mechanism in subcritical and supercritical water, by using a 16-ml autoclave reactor. The major operating parameters investigated include: The reaction temperature, from 673 to 873 K, the reaction pressure, 10 and 25 MPa, the dosage of oxidizing agent, 0 and 0.5 chemical oxygen demand, and the concentration of lactic acid in the feed, 0.5 and 1.0 M. Gaseous products from the conversion were generally found to be comparable to those derived from the conversion of glucose.

Keywords: lactic acid, subcritical water, supercritical water, thermochemical conversion

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7881 Extracting the Atmospheric Carbon Dioxide and Convert It into Useful Minerals at the Room Conditions

Authors: Muthana A. M. Jamel Al-Gburi

Abstract:

Elimination of carbon dioxide (CO2) gas from our atmosphere is very important but complicated, and since there is always an increase in the gas amounts of the other greenhouse ones in our atmosphere, causes by both some of the human activities and the burning of the fossil fuels, which leads to the Global Warming phenomena i.e., increasing the earth temperature to a higher level, creates desertification, tornadoes and storms. In our present research project, we constructed our own system to extract carbon dioxide directly from the atmospheric air at the room conditions and investigated how to convert the gas into a useful mineral or Nano scale fibers made of carbon by using several chemical processes and chemical reactions leading to a valuable building material and also to mitigate the environmental negative change. In the present water pool system (Carbone Dioxide Domestic Extractor), the ocean-sea water was used to dissolve the CO2 gas from the room and converted into carbonate minerals by using a number of additives like shampoo, clay and MgO. Note that the atmospheric air includes CO2 gas has circulated within the sea water by air pump connected to a perforated tubes fixed deep on the pool base. Those chemical agents were mixed with the ocean-sea water to convert the formed acid from the water-CO2 reaction into a useful mineral. After we successfully constructed the system, we did intense experiments and investigations on the CO2 gas reduction level and found which is the optimum active chemical agent to work in the atmospheric conditions.

Keywords: global warming, CO₂ gas, ocean-sea water, additives, solubility level

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7880 Investigation of Knitted Fabric Properties Effect on Evaporation Rate

Authors: N. S. Achour, M. Hamdaoui, S. Ben Nasrallah

Abstract:

Evaporation kinetics of water from porous knitted fabrics are studied: An experimental study of determining evaporated water mass (g) versus time (s) from different knitted fabrics was gravimetrically investigated in various atmospheric conditions. Then evaporation rates are calculated. The goal is to determine the effect of fabric composition, knit structure and yarns properties on evaporation rate. The results show that fabrics geometrical properties, such as porosity and thickness, have a significant influence on evaporated water quantities.

Keywords: evaporation rate, experimental study, geometrical properties, porous knitted fabrics

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7879 Tillage and Manure Effects on Water Retention and Van Genuchten Parameters in Western Iran

Authors: Azadeh Safadoust, Ali Akbar Mahboubi, Mohammad Reza Mosaddeghi, Bahram Gharabaghi

Abstract:

A study was conducted to evaluate hydraulic properties of a sandy loam soil and corn (Zea mays L.) crop production under a short-term tillage and manure combinations field experiment carried out in west of Iran. Treatments included composted cattle manure application rates [0, 30, and 60 Mg (dry weight) ha⁻¹] and tillage systems [no-tillage (NT), chisel plowing (CP), and moldboard plowing (MP)] arranged in a split-plot design. Soil water characteristic curve (SWCC) and saturated hydraulic conductivity (Ks) were significantly affected by manure and tillage treatments. At any matric suction, the soil water content was in the order of MP>CP>NT. At all matric suctions, the amount of water retained by the soil increased as manure application rate increased (i.e. 60>30>0 Mg ha⁻¹). Similar to the tillage effects, at high suctions the differences of water retained due to manure addition were less than that at low suctions. The change of SWCC from tillage methods and manure applications may attribute to the change of pore size and aggregate size distributions. Soil Ks was in the order of CP>MP>NT for the first two layers and in the order of MP>CP and NT for the deeper soil layer. The Ks also increased with increasing rates of manure application (i.e. 60>30>0 Mg ha⁻¹). This was due to the increase in the total pore size and continuity.

Keywords: corn, manure, saturated hydraulic conductivity, soil water characteristic curve, tillage

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7878 A 1H NMR-Linked PCR Modelling Strategy for Tracking the Fatty Acid Sources of Aldehydic Lipid Oxidation Products in Culinary Oils Exposed to Simulated Shallow-Frying Episodes

Authors: Martin Grootveld, Benita Percival, Sarah Moumtaz, Kerry L. Grootveld

Abstract:

Objectives/Hypotheses: The adverse health effect potential of dietary lipid oxidation products (LOPs) has evoked much clinical interest. Therefore, we employed a 1H NMR-linked Principal Component Regression (PCR) chemometrics modelling strategy to explore relationships between data matrices comprising (1) aldehydic LOP concentrations generated in culinary oils/fats when exposed to laboratory-simulated shallow frying practices, and (2) the prior saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA) contents of such frying media (FM), together with their heating time-points at a standard frying temperature (180 oC). Methods: Corn, sunflower, extra virgin olive, rapeseed, linseed, canola, coconut and MUFA-rich algae frying oils, together with butter and lard, were heated according to laboratory-simulated shallow-frying episodes at 180 oC, and FM samples were collected at time-points of 0, 5, 10, 20, 30, 60, and 90 min. (n = 6 replicates per sample). Aldehydes were determined by 1H NMR analysis (Bruker AV 400 MHz spectrometer). The first (dependent output variable) PCR data matrix comprised aldehyde concentration scores vectors (PC1* and PC2*), whilst the second (predictor) one incorporated those from the fatty acid content/heating time variables (PC1-PC4) and their first-order interactions. Results: Structurally complex trans,trans- and cis,trans-alka-2,4-dienals, 4,5-epxy-trans-2-alkenals and 4-hydroxy-/4-hydroperoxy-trans-2-alkenals (group I aldehydes predominantly arising from PUFA peroxidation) strongly and positively loaded on PC1*, whereas n-alkanals and trans-2-alkenals (group II aldehydes derived from both MUFA and PUFA hydroperoxides) strongly and positively loaded on PC2*. PCR analysis of these scores vectors (SVs) demonstrated that PCs 1 (positively-loaded linoleoylglycerols and [linoleoylglycerol]:[SFA] content ratio), 2 (positively-loaded oleoylglycerols and negatively-loaded SFAs), 3 (positively-loaded linolenoylglycerols and [PUFA]:[SFA] content ratios), and 4 (exclusively orthogonal sampling time-points) all powerfully contributed to aldehydic PC1* SVs (p 10-3 to < 10-9), as did all PC1-3 x PC4 interaction ones (p 10-5 to < 10-9). PC2* was also markedly dependent on all the above PC SVs (PC2 > PC1 and PC3), and the interactions of PC1 and PC2 with PC4 (p < 10-9 in each case), but not the PC3 x PC4 contribution. Conclusions: NMR-linked PCR analysis is a valuable strategy for (1) modelling the generation of aldehydic LOPs in heated cooking oils and other FM, and (2) tracking their unsaturated fatty acid (UFA) triacylglycerol sources therein.

Keywords: frying oils, lipid oxidation products, frying episodes, chemometrics, principal component regression, NMR Analysis, cytotoxic/genotoxic aldehydes

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7877 Cost Efficient Receiver Tube Technology for Eco-Friendly Concentrated Solar Thermal Applications

Authors: M. Shiva Prasad, S. R. Atchuta, T. Vijayaraghavan, S. Sakthivel

Abstract:

The world is in need of efficient energy conversion technologies which are affordable, accessible, and sustainable with eco-friendly nature. Solar energy is one of the cornerstones for the world’s economic growth because of its abundancy with zero carbon pollution. Among the various solar energy conversion technologies, solar thermal technology has attracted a substantial renewed interest due to its diversity and compatibility in various applications. Solar thermal systems employ concentrators, tracking systems and heat engines for electricity generation which lead to high cost and complexity in comparison with photovoltaics; however, it is compatible with distinct thermal energy storage capability and dispatchable electricity which creates a tremendous attraction. Apart from that, employing cost-effective solar selective receiver tube in a concentrating solar thermal (CST) system improves the energy conversion efficiency and directly reduces the cost of technology. In addition, the development of solar receiver tubes by low cost methods which can offer high optical properties and corrosion resistance in an open-air atmosphere would be beneficial for low and medium temperature applications. In this regard, our work opens up an approach which has the potential to achieve cost-effective energy conversion. We have developed a highly selective tandem absorber coating through a facile wet chemical route by a combination of chemical oxidation, sol-gel, and nanoparticle coating methods. The developed tandem absorber coating has gradient refractive index nature on stainless steel (SS 304) and exhibited high optical properties (α ≤ 0.95 & ε ≤ 0.14). The first absorber layer (Cr-Mn-Fe oxides) developed by controlled oxidation of SS 304 in a chemical bath reactor. A second composite layer of ZrO2-SiO2 has been applied on the chemically oxidized substrate by So-gel dip coating method to serve as optical enhancing and corrosion resistant layer. Finally, an antireflective layer (MgF2) has been deposited on the second layer, to achieve > 95% of absorption. The developed tandem layer exhibited good thermal stability up to 250 °C in open air atmospheric condition and superior corrosion resistance (withstands for > 200h in salt spray test (ASTM B117)). After the successful development of a coating with targeted properties at a laboratory scale, a prototype of the 1 m tube has been demonstrated with excellent uniformity and reproducibility. Moreover, it has been validated under standard laboratory test condition as well as in field condition with a comparison of the commercial receiver tube. The presented strategy can be widely adapted to develop highly selective coatings for a variety of CST applications ranging from hot water, solar desalination, and industrial process heat and power generation. The high-performance, cost-effective medium temperature receiver tube technology has attracted many industries, and recently the technology has been transferred to Indian industry.

Keywords: concentrated solar thermal system, solar selective coating, tandem absorber, ultralow refractive index

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7876 Two-Phase Flow Modelling and Numerical Simulation for Waterflooding in Enhanced Oil Recovery

Authors: Peña A. Roland R., Lozano P. Jean P.

Abstract:

The waterflooding process is an enhanced oil recovery (EOR) method that appears tremendously successful. This paper shows the importance of the role of the numerical modelling of waterflooding and how to provide a better description of the fluid flow during this process. The mathematical model is based on the mass conservation equations for the oil and water phases. Rock compressibility and capillary pressure equations are coupled to the mathematical model. For discretizing and linearizing the partial differential equations, we used the Finite Volume technique and the Newton-Raphson method, respectively. The results of three scenarios for waterflooding in porous media are shown. The first scenario was estimating the water saturation in the media without rock compressibility and without capillary pressure. The second scenario was estimating the front of the water considering the rock compressibility and capillary pressure. The third case is to compare different fronts of water saturation for three fluids viscosity ratios without and with rock compressibility and without and with capillary pressure. Results of the simulation indicate that the rock compressibility and the capillary pressure produce changes in the pressure profile and saturation profile during the displacement of the oil for the water.

Keywords: capillary pressure, numerical simulation, rock compressibility, two-phase flow

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7875 Identification and Isolation of E. Coli O₁₅₇:H₇ From Water and Wastewater of Shahrood and Neka Cities by PCR Technique

Authors: Aliasghar Golmohammadian, Sona Rostampour Yasouri

Abstract:

One of the most important intestinal pathogenic strains is E. coli O₁₅₇:H₇. This pathogenic bacterium is transmitted to humans through water and food. E. coli O₁₅₇:H₇ is the main cause of Hemorrhagic colitis (HC), Hemolytic Uremic Syndrome (HUS), Thrombotic Thrombocytopenic Purpura (TTP) and in some cases death. Since E. coli O₁₅₇:H₇ can be transmitted through the consumption of different foods, including vegetables, agricultural products, and fresh dairy products, this study aims to identify and isolate E. coli O₁₅₇:H₇ from wastewater by PCR technique. One hundred twenty samples of water and wastewater were collected by Falcom Sterile from Shahrood and Neka cities. The samples were checked for colony formation after appropriate centrifugation and cultivation in the specific medium of Sorbitol MacConkey Agar (SMAC) and other diagnostic media of E. coli O₁₅₇:H₇. Also, the plates were observed macroscopically and microscopically. Then, the necessary phenotypic tests were performed on the colonies, and finally, after DNA extraction, the PCR technique was performed with specific primers related to rfbE and stx2 genes. The number of 5 samples (6%) out of all the samples examined were determined positive by PCR technique with observing the bands related to the mentioned genes on the agarose gel electrophoresis. PCR is a fast and accurate method to identify the bacteria E. coli O₁₅₇:H₇. Considering that E. coli bacteria is a resistant bacteria and survives in water and food for weeks and months, the PCR technique can provide the possibility of quick detection of contaminated water. Moreover, it helps people in the community control and prevent the transfer of bacteria to healthy and underground water and agricultural and even dairy products.

Keywords: E. coli O₁₅₇:H₇, PCR, water, wastewater

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7874 General Formula for Water Surface Profile over Side Weir in the Combined, Trapezoidal and Exponential, Channels

Authors: Abdulrahman Abdulrahman

Abstract:

A side weir is a hydraulic structure set into the side of a channel. This structure is used for water level control in channels, to divert flow from a main channel into a side channel when the water level in the main channel exceeds a specific limit and as storm overflows from urban sewerage system. Computation of water surface over the side weirs is essential to determine the flow rate of the side weir. Analytical solutions for water surface profile along rectangular side weir are available only for the special cases of rectangular and trapezoidal channels considering constant specific energy. In this paper, a rectangular side weir located in a combined (trapezoidal with exponential) channel was considered. Expanding binominal series of integer and fraction powers and the using of reduction formula of cosine function integrals, a general analytical formula was obtained for water surface profile along a side weir in a combined (trapezoidal with exponential) channel. Since triangular, rectangular, trapezoidal and parabolic cross-sections are special cases of the combined cross section, the derived formula, is applicable to triangular, rectangular, trapezoidal cross-sections as analytical solution and semi-analytical solution to parabolic cross-section with maximum relative error smaller than 0.76%. The proposed solution should be a useful engineering tool for the evaluation and design of side weirs in open channel.

Keywords: analytical solution, combined channel, exponential channel, side weirs, trapezoidal channel, water surface profile

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7873 Acid Injection PTFE Internal Lining in Raw Water System

Authors: Fikri Suwaileh

Abstract:

In the reverse osmosis (RO) water treatment plant, operation was suffering from several leaks on the acid injection point spool and downstream spools, due to insufficient injection monitoring and the coating failure leading to pin holes. The paper will go over the background of the leaks in the acid injection point, the process in the RO plant, the material, and coating used in the existing spools, the impact of these repeated leaks, the type of damage mechanism that occurred in the system due to the manner of acid injection and the heat in the spools, which lead to coating failure, leaks and water release. This paper will also look at the analysis, both the short- and long-term recommendations, and the utilization of Teflon internal lining to stop the leaks. Sharing this case study will enhance the knowledge of the importance of taking all factors that will lead to leaks in the acid injection points, along with the importance of utilizing the appropriate coating material lining to enhance the full system.

Keywords: corrosion, coating, raw water, lining

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7872 Water Quality Determination of River Systems in Antalya Basin by Biomonitoring

Authors: Hasan Kalyoncu, Füsun Kılçık, Hatice Gülboy Akyıldırım, Aynur Özen, Mehmet Acar, Nur Yoluk

Abstract:

For evaluation of water quality of the river systems in Antalya Basin, macrozoobenthos samples were taken from 22 determined stations by a hand net and identified at family level. Water quality of Antalya Basin was determined according to Biological Monitoring Working Party (BMWP) system, by using macrozoobenthic invertebrates and physicochemical parameters. As a result of the evaluation, while Aksu Stream was determined as the most polluted stream in Antalya Basin, Isparta Stream was determined as the most polluted tributary of Aksu Stream. Pollution level of the Isparta Stream was determined as quality class V and it is the extremely polluted part of stream. Pollution loads at the sources of the streams were determined in low levels in general. Due to some parts of the streams have passed through deep canyons and take their sources from nonresidential and non-arable regions, majority of the streams that take place in Antalya Basin are at high quality level. Waste water, which comes from agricultural and residential regions, affects the lower basins of the streams. Because of the waste water, lower parts of the stream basins exposed to the pollution under anthropogenic effects. However, in Aksu Stream, which differs by being exposed to domestic and industrial wastes of Isparta City, extreme pollution was determined, particularly in the Isparta Stream part.

Keywords: Antalya basin, biomonitoring, BMWP, water quality

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7871 Sulfamethoxazole Degradation by Conventional Fenton and Microwave-Assisted Fenton Reaction

Authors: Derradji Chebli, Abdallah Bouguettoucha, Zoubir Manaa, Amrane Abdeltif

Abstract:

Pharmaceutical products, such as sulfamethoxazole (SMX) are rejected in the environment at trace level by human and animals (ng/L to mg/L), in their original form or as byproducts. Antibiotics are toxic contaminants for the aquatic environment, owing to their adverse effects on the aquatic life and humans. Even at low concentrations, they can negatively impact biological water treatment leading to the proliferation of antibiotics-resistant pathogens. It is therefore of major importance to develop efficient methods to limit their presence in the aquatic environment. In this aim, advanced oxidation processes (AOP) appear relevant compared to other methods, since they are based on the production of highly reactive free radicals, and especially ●OH. The objective of this work was to evaluate the degradation of SMX by microwave-assisted Fenton reaction (MW/Fe/H2O2). Hydrogen peroxide and ferrous ions concentrations, as well as the microwave power were optimized. The results showed that the SMX degradation by MW/Fe/H2O2 followed a pseudo-first order kinetic. The treatment of 20 mg/L initial SMX by the Fenton reaction in the presence of microwave showed the positive impact of this latter owing to the higher degradation yields observed in a reduced reaction time if compared to the conventional Fenton reaction, less than 5 min for a total degradation. In addition, increasing microwave power increased the degradation kinetics. Irrespective of the application of microwave, the optimal pH for the Fenton reaction remained 3. Examination of the impact of the ionic strength showed that carbonate and sulfate anions increased the rate of SMX degradation.

Keywords: antibiotic, degradation, elimination, fenton, microwave, polluant

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7870 Influence of Freeze-Thaw Cycles on Protein Integrity and Quality of Chicken Meat

Authors: Nafees Ahmed, Nur Izyani Kamaruzman, Saralla Nathan, Mohd Ezharul Hoque Chowdhury, Anuar Zaini Md Zain, Iekhsan Othman, Sharifah Binti Syed Hassan

Abstract:

Meat quality is always subject to consumer scrutiny when purchasing from retail markets on mislabeling as fresh meat. Various physiological and biochemical changes influence the quality of meat. As a major component of muscle tissue, proteins play a major role in muscle foods. In meat industry, freezing is the most common form of storage of meat products. Repeated cycles of freezing and thawing are common in restaurants, kitchen, and retail outlets and can also occur during transportation or storage. Temperature fluctuation is responsible for physical, chemical, and biochemical changes. Repeated cycles of ‘freeze-thaw’ degrade the quality of meat by stimulating the lipid oxidation and surface discoloration. The shelf life of meat is usually determined by its appearance, texture, color, flavor, microbial activity, and nutritive value and is influenced by frozen storage and subsequent thawing. The main deterioration of frozen meat during storage is due to protein. Due to the large price differences between fresh and frozen–thawed meat, it is of great interest to consumer to know whether a meat product is truly fresh or not. Researchers have mainly focused on the reduction of moisture loss due to freezing and thawing cycles of meat. The water holding capacity (WHC) of muscle proteins and reduced water content are key quality parameters of meat that ultimately changes color and texture. However, there has been limited progress towards understanding the actual mechanisms behind the meat quality changes under the freeze–thaw cycles. Furthermore, effect of freeze-thaw process on integrity of proteins is ignored. In this paper, we have studied the effect of ‘freeze-thawing’ on physicochemical changes of chicken meat protein. We have assessed the quality of meat by pH, spectroscopic measurements, Western Blot. Our results showed that increase in freeze-thaw cycles causes changes in pH. Measurements of absorbance (UV-visible and IR) indicated the degradation of proteins. The expression of various proteins (CREB, AKT, MAPK, GAPDH, and phosphorylated forms) were performed using Western Blot. These results indicated the repeated cycles of freeze-thaw is responsible for deterioration of protein, thus causing decrease in nutritious value of meat. It damges the use of these products in Islamic Sharia.

Keywords: chicken meat, freeze-thaw, halal, protein, western blot

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7869 Preliminary Investigation into the Potentials of Mixed Blend of Acha (Digitaria exiles), Aya (Cyperus esculenta) and Defatted Water Melon Seed (Citrullis lanatus) Flour as a Weaning Formula

Authors: O. G. Onuoha, O. G. Akagu

Abstract:

The potentials of acha (Digitaria exiles), aya (Cyperus esculentus) and defatted water melon seed (Citrullis lanatus) as a weaning formula was investigated using the following blends for acha, aya and defatted water melon seed respectively in percentage proportion to obtain the weaning formulae; WS1(20:50:30); WS2(30:40:30); WS3(40:30:30); WS4(50:20:30). The result of the chemical analysis showed that; the sample WS1 had the highest value (15.6%) for protein while sample WS4 had the least value (14.1%). The fat content sample WS4 having the highest value (30.8%) while sample WS1 had the least value (27.3%). The ash content sample WS4 had the highest value (3.22%) while sample WS1 had the least value (2.63%). The carbohydrate content showed that sample WS1 having the highest value (50.5%) while sample WS4 had the least value (46.58%). While sample WS4 had the highest energy value (528.32 Kcal) and sample WS2 had the least value (515.06 Kcal). However, all the sample results fell within the dietary daily reference intake for infants between 0-3 years and required only local technology in its production.

Keywords: weaning formula, acha, aya, deffted water melon seed

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7868 An Inorganic Nanofiber/Polymeric Microfiber Network Membrane for High-Performance Oil/Water Separation

Authors: Zhaoyang Liu

Abstract:

It has been highly desired to develop a high-performance membrane for separating oil/water emulsions with the combined features of high water flux, high oil separation efficiency, and high mechanical stability. Here, we demonstrated a design for high-performance membranes constructed with ultra-long titanate nanofibers (over 30 µm in length)/cellulose microfibers. An integrated network membrane was achieved with these ultra-long nano/microfibers, contrast to the non-integrated membrane constructed with carbon nanotubes (5 µm in length)/cellulose microfibers. The morphological properties of the prepared membranes were characterized by A FEI Quanta 400 (Hillsboro, OR, United States) environmental scanning electron microscope (ESEM). The hydrophilicity, underwater oleophobicity and oil adhesion property of the membranes were examined using an advanced goniometer (Rame-hart model 500, Succasunna, NJ, USA). More specifically, the hydrophilicity of membranes was investigated by analyzing the spreading process of water into membranes. A filtration device (Nalgene 300-4050, Rochester, NY, USA) with an effective membrane area of 11.3 cm² was used for evaluating the separation properties of the fabricated membranes. The prepared oil-in-water emulsions were poured into the filtration device. The separation process was driven under vacuum with a constant pressure of 5 kPa. The filtrate was collected, and the oil content in water was detected by a Shimadzu total organic carbon (TOC) analyzer (Nakagyo-ku, Kyoto, Japan) to examine the separation efficiency. Water flux (J) of the membrane was calculated by measuring the time needed to collect some volume of permeate. This network membrane demonstrated good mechanical flexibility and robustness, which are critical for practical applications. This network membrane also showed high separation efficiency (99.9%) for oil/water emulsions with oil droplet size down to 3 µm, and meanwhile, has high water permeation flux (6.8 × 10³ L m⁻² h⁻¹ bar⁻¹) at low operation pressure. The high water flux is attributed to the interconnected scaffold-like structure throughout the whole membrane, while the high oil separation efficiency is attributed to the nanofiber-made nanoporous selective layer. Moreover, the economic materials and low-cost fabrication process of this membrane indicate its great potential for large-scale industrial applications.

Keywords: membrane, inorganic nanofibers, oil/water separation, emulsions

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7867 Decision Support Tool for Selecting Appropriate Sustainable Rainwater Harvesting Based System in Ibadan, Nigeria

Authors: Omolara Lade, David Oloke

Abstract:

The approach to water management worldwide is currently in transition, with a shift from centralised infrastructures to greater consideration of decentralised technologies, such as rainwater harvesting (RWH). However, in Nigeria, implementation of sustainable water management, such as RWH systems, is inefficient and social, environmental and technical barriers, concerns and knowledge gaps exist, which currently restrict its widespread utilisation. This inefficiency contributes to water scarcity, water-borne diseases, and loss of lives and property due to flooding. Meanwhile, several RWH technologies have been developed to improve SWM through both demand and storm-water management. Such technologies involve the use of reinforced concrete cement (RCC) storage tanks, surface water reservoirs and ground-water recharge pits as storage systems. A framework was developed to assess the significance and extent of water management problems, match the problems with existing RWH-based solutions and develop a robust ready-to-use decision support tool that can quantify the costs and benefits of implementing several RWH-based storage systems. The methodology adopted was the mixed method approach, involving a detailed literature review, followed by a questionnaire survey of household respondents, Nigerian Architects and Civil Engineers and focus group discussion with stakeholders. 18 selection attributes have been defined and three alternatives have been identified in this research. The questionnaires were analysed using SPSS, excel and selected statistical methods to derive weightings of the attributes for the tool. Following this, three case studies were modelled using RainCycle software. From the results, the MDA model chose RCC tank as the most appropriate storage system for RWH.

Keywords: rainwater harvesting, modelling, hydraulic assessment, whole life cost, decision support system

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7866 A Sustainable and Low-Cost Filter to Treat Pesticides in Water

Authors: T. Abbas, J. McEvoy, E. Khan

Abstract:

Pesticide contamination in water supply is a common environmental problem in rural agricultural communities. Advanced water treatment processes such as membrane filtration and adsorption on activated carbon only remove pesticides from water without degrading them into less toxic/easily degradable compounds leaving behind contaminated brine and activated carbon that need to be managed. Rural communities which normally cannot afford expensive water treatment technologies need an economical and sustainable filter which not only treats pesticides from water but also degrades them into benign products. In this study, iron turning waste experimented as potential point-of-use filtration media for the removal/degradation of a mixture of six chlorinated pesticides (lindane, heptachlor, endosulfan, dieldrin, endrin, and DDT) in water. As a common and traditional medium for water filtration, sand was also tested along with iron turning waste. Iron turning waste was characterized using scanning electron microscopy and energy dispersive X-Ray analyzer. Four glass columns with different filter media layer configurations were set up: (1) only sand, (2) only iron turning, (3) sand and iron turning (two separate layers), and (4) sand, iron turning and sand (three separate layers). The initial pesticide concentration and flow rate were 2 μg/L and 10 mL/min. Results indicate that sand filtration was effective only for the removal of DDT (100%) and endosulfan (94-96%). Iron turning filtration column effectively removed endosulfan, endrin, and dieldrin (85-95%) whereas the lindane and DDT removal were 79-85% and 39-56%, respectively. The removal efficiencies for heptachlor, endosulfan, endrin, dieldrin, and DDT were 90-100% when sand and iron turning waste (two separate layers) were used. However, better removal efficiencies (93-100%) for five out of six pesticides were achieved, when sand, iron turning and sand (three separate layers) were used as filtration media. Moreover, the effects of water pH, amounts of media, and minerals present in water such as magnesium, sodium, calcium, and nitrate on the removal of pesticides were examined. Results demonstrate that iron turning waste efficiently removed all the pesticides under studied parameters. Also, it completely de-chlorinated all the pesticides studied and based on the detection of by-products, the degradation mechanisms for all six pesticides were proposed.

Keywords: pesticide contamination, rural communities, iron turning waste, filtration

Procedia PDF Downloads 253
7865 Performance Evaluation of Filtration System for Groundwater Recharging Well in the Presence of Medium Sand-Mixed Storm Water

Authors: Krishna Kumar Singh, Praveen Jain

Abstract:

The collection of storm water runoff and forcing it into the groundwater is the need of the hour to sustain the ground water table. However, the runoff entraps various types of sediments and other floating objects whose removal are essential to avoid pollution of ground water and blocking of pores of aquifer. However, it requires regular cleaning and maintenance due to the problem of clogging. To evaluate the performance of filter system consisting of coarse sand (CS), gravel (G) and pebble (P) layers, a laboratory experiment was conducted in a rectangular column. The effect of variable thickness of CS, G and P layers of the filtration unit of the recharge shaft on the recharge rate and the sediment concentration of effluent water were evaluated. Medium sand (MS) of three particle sizes, viz. 0.150–0.300 mm (T1), 0.300–0.425 mm (T2) and 0.425–0.600 mm of thickness 25 cm, 30 cm, and 35 cm respectively in the top layer of the filter system and having seven influent sediment concentrations of 250–3,000 mg/l were used for the experimental study. The performance was evaluated in terms of recharge rates and clogging time. The results indicated that 100 % suspended solids were entrapped in the upper 10 cm layer of MS, the recharge rates declined sharply for influent concentrations of more than 1,000 mg/l. All treatments with a higher thickness of MS media indicated recharge rate slightly more than that of all treatment with a lower thickness of MS media respectively. The performance of storm water infiltration systems was highly dependent on the formation of a clogging layer at the filter. An empirical relationship has been derived between recharge rates, inflow sediment load, size of MS and thickness of MS with using MLR.

Keywords: groundwater, medium sand-mixed storm water filter, inflow sediment load

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7864 ZnO / TiO2 Nanoparticles for Degradation of Cyanide Ion

Authors: Masoumeh Tabatabaee, Zahra Shahryarzadeh, Masoud R. Shishebor

Abstract:

Advanced oxidation process (AOPs) is alternative method for the complete degradation many organic pollutants. When a photocatalyst absorbs radiation whose energy hν > Eg an ē from its filled valance band (VB) is promoted to its conduction band (CB) and valance band holes h+ are formed. Electron would reduce any available species, including O2, water and hydroxide ion to form hydroxyl radicals. ZnO and TiO2 are important photocatalysts with high catalytic activity that have attracted much research attention. TiO2 can only absorb a small portion of solar spectrum in the UV region and many methods such as dye sensitization, doping of other metals and using TiO2 with another semiconductor have been used to improve the photocatalytic activity of TiO2 under solar irradiation. Studies have shown that the use of metal oxides or sulfide such as WO3, MoO3, SiO2, MgO, ZnO, and CdS with TiO2 can significantly enhance the photocatalytic activity of TiO2. Due to similarity of photodegradation mechanism of ZnO with TiO2, it is a suitable semiconductor using with TiO2 and recently nanosized bicomponent TiO2-ZnO photocatalysts were prepared and used for degradation of some pollutants. In this study, Nano-sized ZnO/TiO2 composite was synthesized. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the structure and morphology of it. The effect of photocatalytic activity of prepared ZnO/TiO2 on the degradation of cyanide ion under UV was investigated. The effect of various parameters such as ZnO/TiO2 concentration, amount of photocatalyst, amount of H2O2, initial dye or cyanide ion concentration, pH and irradiation time on were investigated. Results show that more than 95% of 4 mgL-1 cyanide ion degraded after 60-min reaction time and under UV irradiation.

Keywords: photodegradation, ZnO/TiO2, nanoparticle, cyanide ion

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7863 People's Perspective on Water Commons in Trans-Boundary Water Governance: A Case Study from Nepal

Authors: Sristi Silwal

Abstract:

South Asian rivers support ecosystems and sustain well-being of thousands of riparian communities. Rivers however are also sources of conflict between countries and one of the contested issues between governments of the region. Governments have signed treaties to harness some of the rivers but their provisions have not been successful in improving the quality of life of those who depend on water as common property resources. This paper will present a case of the study of the status of the water commons along the lower command areas of Koshi, Gandka and Mahakali rivers. Nepal and India have signed treaties for development and management of these rivers in 1928, 1954 and 1966. The study investigated perceptions of the local community on climate-induced disasters, provision of the treaties such as water for irrigation, participation in decision-making and specific impact of women. It looked at how the local community coped with adversities. The study showed that the common pool resources are gradually getting degraded, flood events increasing while community blame ‘other state’ and state administration for exacerbating these ills. The level of awareness about provisions of existing treatise is poor. Ongoing approach to trans-boundary water management has taken inadequate cognizance of these realities as the dominant narrative perpetuates cooperation between the governments. The paper argues that on-going discourses on trans-boundary water development and management need to use a new metrics of taking cognizance of the condition of the commons and that of the people depended on them for sustenance. In absence of such narratives, the scale of degradation would increase making those already marginalized more vulnerable to impacts of global climate change.

Keywords: climate change vulnerability, conflict, cooperation, water commons

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7862 Study Technical Possibilities of Agricultural Reuse of by-Products from Treatment Plant of Boumerdes, Algeria

Authors: Kadir Mokrane, Souag Doudja

Abstract:

In Algeria, one of the Mediterranean countries, water resources are limited and unevenly distributed in space and in time. Boumerdes, coastal town of Algeria, known for its farming and fishing activities. The region is also known for its semi-arid climate and a large water deficit. In order to preserve the quality of water bodies and to reduce withdrawals in the natural environment, it is necessary to seek alternative supplies. The reuse of treated wastewater seems to be a good alternative, especially for irrigation. In the framework of sustainable development, it is imperative to rationalize the use of water resources conventional and unconventional. That is why the re-use agricultural of by-products of the treatment is an alternative expected to preserve the environment and promotion of the agricultural sector. The present work aims, to search for the possibility of reuse of treated wastewater, and sludge resulting from treatment plant of the city of Boumerdes in agriculture, through the analysis of physical, chemical and bacteriological on the samples, and the continuous monitoring of the evolution of several elements during the period of study extended over 12 months, and then, the comparison of these test results to standards and guidelines established in the framework of irrigation and land application.

Keywords: treated water, sewage sludge, recycling, agriculture

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7861 Environmental Contamination of Water Bodies by Waste Produced by Slaughterhouses and the Prevalence of Waterborne Diseases in Kumba Municipality

Authors: Maturin Désiré Sop Sop, Didien Njumba Besende, Samuel Fosso Wamba

Abstract:

This study seeks to examine the nexus between drinking water sources in the Kumba municipality and its related health implications vis-à-vis the recurrent incidences of waterborne diseases such as Typhoid, Cholera, Diarrhea, Dysentery, Hepatitis A and malaria. The study adopted a purposive sampling technique in which surveys were conducted between the months of June to December 2022. 150 questionnaires were retrieved from the 210 administered to the affected population of Kosala, Buea Road and Mambanda. Information for the study was collected using surveys, questionnaires, key informant interviews, the laboratory analysis of collected drinking water samples, the researcher’s direct observation as well and hospital reports on the prevalence of waterborne diseases. Water samples from the nearby streams and wells, which were communally used by the local population for drinking, and five slaughterhouses within the affected areas were laboratory tested to determine alterations in their chemical, physical and microbiological characteristics. The collected water samples from all the streams and wells used for drinking were tested for changes in properties such as temperature, turbidity, EC, pH, TDS, TSS, Cl, SO42-, PO43-, NO3-, Fe, Na, BOD, COD, DO, E.coli and total coliform concentration. These results were then compared with the WHO regulations for water quality. The results from the laboratory analysis of drinking water sources, which were at the same time used by the surrounding abattoirs revealed significant alterations in the water quality parameters such as temperature, turbidity, EC, pH, TDS, TSS, Cl, SO42-, PO43-, NO3-, Fe, Na, BOD, COD, DO, E.coli and total coliform concentration. This is due to the channeling of untreated wastes into the different drinking water points as well as the inter-use of dirty utensils such as buckets from slaughterhouses to fetch water from the streams and wells that serve as drinking water sources for the local population. On the human health aspect, the results were later compared with hospital data, and they revealed that the consumption of such contaminated water in the localities of Kosala, Mambanda, and Buea road negatively affected the local population because of the high incidences of Typhoid Cholera, Diarrhea, Dysentery, Hepatitis A and malaria. The poor management of drinking water sources pollutes streams and significantly exposes the local population to lots of waterborne diseases. Efforts should be made to provide clean pipe-borne water to the affected localities of Kumba as well as to ensure the proper management of wastes.

Keywords: drinking water, diseases, Kumba, municipality

Procedia PDF Downloads 76