65 research outputs found
Kinetic study on removal of heavy metal ions from aqueous solution by using soils
Kinetic study on removal of heavy metal ions from aqueous solution by using soi
Removal of Heavy Metal Ions Using Magnetic Materials
Heavy metal ions contaminate water environment through point sources
and nonpoint sources. Heavy metal ions are categorized as inorganic contaminants
by both the WHO and the USEPA. The heavy metal ions are increasingly being
introduced into the environment as pollutants and contaminants resulting from
human activities.
Magnetic particles for water treatment applications have received considerable
attention from researchers due to high separation efficiency. The magnetic particles
behave similar to or even better than various commercial adsorbents. The magnetic particles also exhibit high selectivity for the target pollutants from the environment
besides enabling ease of operation for reducing the particle separation steps from the
flowing stream. A comprehensive and systematic understanding of synthesis and
surface modifications of magnetic particles is significant to enhance their practicability in environmental technology. Although high removal performance and reactivity can be achieved by smaller particle size, the stability, toxicity, and recovery of
the particles magnetically could be challenging.
In contrast, the active surface of magnetic particles may be forfeited, while
surface modifications stabilize and reduce the toxicity of the particles. Reliable
surface modifications are necessarily needed for the increment of the number of
active sites to remove the heavy metals. For successful environmental applications of
the magnetic particles, modification on the magnetic particles is principally crucial to
balance the effects on their reactivity, capacity, and reusability
Environmental Management Systems (EMS) Adoption in Sarawak (Malaysia): Implementation Motivations
Environmental management has been in the process of evolution since Industrial Revolutions of 18th and 19th centuries. And the more recent is the development of international environmental management standards and guidelines to facilitate global trade. These environmental management standards and guidelines are usually known as Environmental Management Systems (EMS). This research investigates the implementation motivations in relation to EMS adoption in Sarawak, Malaysia organizations. Empirical findings of a survey on the above in Sarawak organizations are presented. About 112 survey questionnaires invitations were forwarded to various organizations in Sarawak and a total of 47 responses were received. The results of this research show that among the Sarawak organizations, the top three implementation motivations or benefits from implementing EMS according to their importance by the Sarawak EMS user’s organizations are 1) Legal compliance as the top benefit of EMS implementation; 2) Improvement in operational environmental protection; and 3) Corporate image advantages.Environmental management has been in the process of evolution since Industrial Revolutions of 18th and 19th centuries. And the more recent is the development of international environmental management standards and guidelines to facilitate global trade. These environmental management standards and guidelines are usually known as Environmental Management Systems (EMS). This research investigates the implementation motivations in relation to EMS adoption in Sarawak, Malaysia organizations. Empirical findings of a survey on the above in Sarawak organizations are presented. About 112 survey questionnaires invitations were forwarded to various organizations in Sarawak and a total of 47 responses were received. The results of this research show that among the Sarawak organizations, the top three implementation motivations or benefits from implementing EMS according to their importance by the Sarawak EMS user’s organizations are 1) Legal compliance as the top benefit of EMS implementation; 2) Improvement in operational environmental protection; and 3) Corporate image advantages
Utilization of agro-wastes to produce biofertilizer
The objective of this study was to develop a simple and cost-effective method to produce biofertilizer using agro-wastes. There were five types of agro-wastes being used in this study. They were wastes from watermelon, papaya, pineapple, citrus orange, and banana. Solid-state fermentation method was used to produce biofertilizer, which was then applied into vegetable plantation. Physical property tests were done on the plant samples of 5 weeks of age in order to determine the effectiveness of the biofertilizer. The results of the experiment showed that the plant samples treated with biofertilizer from watermelon, papaya, and banana wastes had promising physical characteristics. Other tests such as analyses of pH values and potassium content in the biofertilizers were also done in this research. It was found that watermelon biofertilizer had the highest pH value (5.15). The banana biofertilizer had the highest content of potassium with a content of 3.932 g K/L
Study On Electrostatic Extrusion Method For Synthesizing Calcium Alginate Encapsulated Iron Oxide
Electrostatic extrusion method is used to produce polymer beads by dripping polymer mixtures into hardening solution using syringing system with electrostatic charges. Through this method, iron oxide particles can be encapsulated into calcium alginate polymer beads. The changes in characteristics of the produced bead can be observed through changing the physical parameter values of applied voltage, height of electrodes, flow rate, and needle sizes of the system. From experimental study using Response Surface Methodology (RSM) modeling, the diameter of produced beads significantly decreases when applied voltage increases and needle size decreases. The optimum parameters from RSM is determined as 4kV applied voltage, 2cm of electrodes height and 0.4mm of needle diameter while flow rate does not contribute significant effect on the system. Furthermore, instrumental and analytical studies are carried out to characterize the produced bead based on the bead sizes, sphericity, surface area and surface morphology. Other than that, a mathematical model is developed from basic equations related to the system on production of calcium alginate encapsulated iron oxide. The model is then improvised and validated via experiment and it shows good agreement with the experiment result where error of the models is 0.4% for bead diameter and 2.5% for bead sphericity
Kinetic Study on Heavy Metal Divalent Ions Removal using Zirconium-Based Magnetic Sorbent
In this research, zirconium-based magnetic sorbent synthesised by chemical co-precipitation method is explored as a potential sorbent for removal of divalent metal ions from aqueous solution. The interaction characteristics between the ions and the sorbent were elucidated by instrumental analyses such as Fourier Transform InfraRed (FT-IR) Spectroscopy, Scanning Electron Microscopy (SEM), and Brunauer, Emmett, and Teller (BET) surface area analyser. Results show that the sorption rate was increased with an increase in contact time and initial metal ion concentration. Moreover, a two-stage kinetics behaviour was observed, and all the batch experiments achieved an equilibrium state within 4 hours. The evaluation of the adsorption behaviour of heavy metal divalent ions onto the magnetic sorbent was explained using two kinetic models, and it was mostly found to follow the postulate of the pseudo-second-order kinetic model. The validity of kinetic models applied in this study is also evaluated by using a normalised standard deviation
Emerging Biosorption, Adsorption,Ion Exchange, and Membrane Technologies
In the last 20 yr, the water industry has been faced with a series of great challenges. Industries have discharged wastewater that contains various new compounds. In addition, the demand for high-quality water has been significantly increasing. As a result, new water treatment technologies have been developed. In this chapter, three novel technologies are introduced. The emerging technologies for the removal of heavy metals, disinfection byproducts, total organic carbons (TOC), and arsenic are illustrated
Physiochemical Characteristic of Sago (Metroxylon Sagu) Starch Production Wastewater Effluents
The physiochemical characteristics of sago starch production wastewater effluents was recently studied. Sago wastewater effluent samples were obtained from a sago factory located in Sarawak, Malaysia and sent to accredited laboratories for particle size distribution and water quality analyses. The findings of this study concluded that sago wastewater effluents from this region are whitish and greyish brown (pH 4.20) in color with majority supra-colloidal or settable suspended solids of particle size ranged from 4.477 µm to 1.18 mm (of 95% volume). The starch content of this wastewater effluents are less than 7% whilst the pollutant parameters (total suspended solids, biochemical oxygen demand and chemical oxygen demand) measured 10,900 mg/L, 5,820 mg/L and 10,220 mg/L, respectively. Pre-filtration of the wastewater effluents has resulted reduction of the
pollutants content as high as 66% of total suspended solids, 20% of biochemical oxygen demand and 22% of chemical oxygen demand while improved pH in a range of 0.05-0.45%
A Parabolic-Curvilinear Reverse-Flow Air-Flotation System (PAF) for Removal of Suspended Solids in Sago Starch Production Wastewater Effluents
A Parabolic-Curvilinear Reverse-Flow Air-Flotation
Treatment System (PAF) was recently developed for the
removal of total suspended solids from sago starch production wastewater effluents. The primary components of the system consist of a parabolic-curved plate, a series of water pumps, an air curtain and valve-froth collection plates to repeat bubbling treatment in a gradually increasing movement flow. Performance tests were carried out by using synthesized sago wastewaters. Performance tests were carried out to determine the total suspended solids and turbidity removal efficiencies.
Total suspended solids of the synthesized sago wastewaters
ranged from 95 to 515 mg/L, 86.9 to 413 NTU for turbidity
and 5.44 to 7.43 for pH. The total suspended solids and
turbidity removal efficiencies of this system were found to be proportional to residence time, and inversely proportional to influent flowrate. The highest achievable total suspended solids and turbidity removal efficiencies for this treatment system recorded 85.63% and 77.89%, respectively. The presence of parabolic-curved plate in the system could improve the removal efficiencies as high as 34.22% for total suspended solids and 37.82% for turbidity. The system performance can further be improved by 13.65% for total suspended solids removal and 24.49% for turbidity removal with the installation of air curtain whilst 9.04% for total suspended solids removals and 6.03% for turbidity removals with the installation of water pumps in the system. Additional 17.2% of total suspended solids and 3.1% of turbidity level removals could be achieved by application of chemicals, i.e., alum and sodium aluminate
Inclined Injection of Supersonic Steam into Subcooled Water A CFD Analysis
The phenomenon of direct-contact condensation gains attention because of various industrial applications; nuclear reactor emergency core cooling systems,steam driven jet injectors, direct-contact heat exchangers etc..The phenomenon was investigated computationally by injecting an inclined steam jet using a supersonic nozzle submerged in subcooled water. The condensation
mechanism is based on two resistance model, which involves consideration of the heat transfer process on both sides of the interface along with use of a variable steam bubble diameter. For computations, ANSYS Fluent based Euler-Euler multiphase model is used. The angle of inclination varies from 5o to 45o at constant inlet pressure of 7 bars with water temperature of 30oC. The
maximum penetration length is achieved using a right angled vertical injection
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