75 research outputs found
Numerical studies of fluid flow across a cosmo ball by using CFD
Cosmo ball is a media used in wastewater treatment to increase the surface area of contact and provide longer contact time for biological activities. It is usually placed as a media or as packing in the aeration tank, BioFil tank or even in the activated sludge tank. It induces the growth of bacteria on its surface, which will serve as a contact area for the wastewater and the microbial. The objective of this simulation is to analyze the flow pattern around the Cosmo ball which is been packed in the wastewater treatment tank. By conducting this analysis, the overall insights on the interaction of the fluid flow with the Cosmo ball surface can be visualize. The velocity of the fluid flow across the ball is at a speed of 2 cm sec-1. The velocity was obtained from the conventional wastewater treatment plant. During the simulation process, the model will undergo each section of program in ANSYS™ Computational Fluid Dynamics (CFD) such as Design Modeler, Meshing, Pre-Processing, Solver and Post-Processing. The flow distribution across the Cosmo ball was analyzed by varying the angle of attack of the flow. The rationale for this simulation arrangement is that the ball could take any orientation in the bulk media and the fluid flow across it would be at random angle. The result shows that the flow around the Cosmo ball was dispersing sideways thus inducing mixing in the wastewater system. Retention of flow has been observed to occur in the Cosmo ball. The retention of flow provides better microbial interaction with the wastewater
Removal of lactose from highly goat's milk concentration through ultrafiltration membrane
Concentration of goat milk using cross-flow filtration unit with 10KDa molecular weight cut off (MCWO)-sized ultrafiltration membrane was examined under various operating conditions. The parameters to be optimized are trans-membrane pressure (TMP) and cross-flow velocity. Permeate flux is decreased with time due to fouling of the membrane. The localized membrane fouling may be reduced by increasing the feed flow rate and TMP to mitigate overall membrane fouling. By doing so, the transmission of lactose will also increase. The aim is to produce concentrated goat milk with minimal lactose content and thus high concentration of protein. Spray-drying method is used to convert the concentrated non-lactose milk obtained into milk powder. The milk powder then was characterized in terms of its surface particle, solubility, and nutritional content with the well-commercialized non-lactose milk. This project tackles understanding to minimize the deposition rates of particles on membrane by optimizing the involved parameters and be proved by comparing the yield obtained with well-commercialized non-lactose milk
Numerical method on drug release from Nanoparticles using CFD.
Nowadays, there are many ways to administer the huge variety of drugs that are on the market. A drug is a chemical substance, that when applied to a living creature, alters its body function. Many drugs are used daily, such as caffeine in coffee and aspirin for pain. A route of drug administration in pharmacology and toxicology is the path by which a drug is brought into contact with the body. The most critical issue is some drugs are not significantly absorbed into the bloodstream. There are thousands of questions on the drug diffusion in the bloodstream and the most common issue is how long will these micro particles drug be released from the tablet? Thus, to identify the rate of the drug release and to control the drug release in our body is important, where to meet the target and not to become a waste. The Computational Fluid Dynamics method was used to investigate the drug design and diffusion profiles with time during the process of degradation and diffusion in water
Separation of lactose from raw goat's milk by cross-flow hollow fiber ultrafiltration membrane
An extensive amount of research has reported on the use of ultrafiltration (UF) membrane, particularly in the improvement of membrane performance efficiency on cow’s milk. However, a very limited number of researches reported on using UF for producing low-lactose goat’s milk due to inherently low lactose. Nonetheless, goat’s milk is still not suitable to be consumed in a large amount by people who are lactose intolerant, especially among Asians, where over 90% of the populations are suffering from lactose intolerance. Until today, fouling and concentration polarization (CP) on membrane surface in cross-flow hollow fiber UF unit are the major problems in the dairy industry. Discovery on how to overcome the problem is still in a hot debate due to the nature’s complex composition in milk. One way to overcome this problem is by evaluating the effects of processing parameters such as trans-membrane pressure (TMP) and feed-flow rate on flux (J), lactose rejection (Ri), concentration factor (CF), and accumulation rate (AR) during the fractionation of lactose. In terms of lactose fractionation for 5 KDa and 10 KDa UF membranes, the TMPs examined were 0.41, 0.55, and 0.69 bars, while feed flow-rates examined were 0.18, 0.34, 0.54, and 0.74 L/min. 5 KDa membrane shows that feed flow-rate and flux behave in a direct relationship, while an inverse relationship in 10 KDa membrane. Both membranes showed that TMP 0.55 bar exhibit the best flux value without reaching the limiting flux region, but with feed flow rate of 0.74 L/min in 5 KDa, while 0.18 L/min in 10 KDa membrane. Lactose rejection percentage (%Ri) is the lowest with 77.71% in 5 KDa membrane while 66.28% in 10 KDa membrane. This can be summarized that the best parameters for 5 KDa membrane is at TMP 0.55 bar with feed flow-rate of 0.74 L/min, while for 10 KDa membrane is at TMP 0.55 bar with feed flow-rate of 0.18 L/min. Due to higher flux value and lowest lactose rejection obtained from low feed flow-rate, 10 KDa UF membrane size was chosen over 5 KDa. As a conclusion, a high degree of lactose removal from goat’s milk could be achieved by 10 KDa UF membrane in a cross-flow hollow fiber system, which proved that different outcomes between 5 KDa and 10 KDa membranes and feed flow-rate required is closely associated to UF pore size and molecular weight of feed solute particles
Industrial radiotracer application for flow rate measurement using Ba-137m radioisotope
Measurement of discharge rates of fluids and solids is an essential requirement in industrial systems. Industrial processes worldwide are progressively recognizing the value of industrial radiotracer application in studying the operation of the on-line plant. Radiotracer techniques are widely used for measurement of fluids/solids in situations where conventional techniques cannot be applied. This present report describes the flow rate measurement using radioisotope technique using unsealed radioactive source to calibrate the installed flowmeters and to measure the flow rate in systems, which does not influence the on-line process. An investigation was performed by the injection of a radiotracer inside the multiphase flow rig system to provide fluid flow rate information. In this study, the multiphase rig was filled up with mixed oil-water, and the Coriolis flowmeter was installed in the system for efficiency validation. Cs-137/Ba-137m radioisotope generators were used to prepare the radiotracer and Ba-137m radioisotopes having activity about 0.2 mCi. The peak to peak method was applied for the radiotracer techniques. The average volumetric flow rate of multiphase flow rig was measured to be 6.43 m3/h. This study has proved that Coriolis flowmeter is not functioning in good condition due to different flow rate value from the experimental works and suggested to be recalibrated or replace
Preparation, antioxidant potential and angiotensin converting enzyme (ACE) inhibitory activity of gum Arabic-stabilised magnesium orotate nanoparticles
The present work investigated the antioxidant properties and antihypertensive activity of magnesium orotate (MgOr) using various established in vitro assays, such as β-carotene bleaching activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and nitric oxide scavenging activity as well as angiotensin converting enzyme (ACE) inhibitory activity. Magnesium orotate nanoparticles (MgOrGANPs) were prepared using the gum arabic (GA) as stabiliser coatings for nanoparticles through freeze-drying method. The in vitro cytoxicity of MgOrGANPs against human breast cancer MCF7, liver cancer HepG2, and colon cancer HT29 was investigated. The nitric oxide (NO) and DPPH scavenging assays of MgOrGANPs showed a dose-dependent trend, while 500 and 200 μL/mL were significantly more effective than the other concentrations with an IC50 of 89.56 μg/mL and 63.22% DPPH scavenging capacity respectively. The exposure of human cancer cells to MgOrGANPs at 1.56 – 1,000 μg/mL using 3-)4,5-dimethylthiazol-2-yl(2,5-diphenyl tetrazolium bromide (MTT) inhibited the growth of cell lines examined in a dose-dependent manner. Hence, MgOrGANPs may have great potential to be applied for cancer treatments
Adsorption of Copper from aqueous solution by chitosan using molecular imprinting technology
In nature chitosan is a plentiful polymer with high heavy metal ion uptake capacity due to chitosan’s functional groups that chelate with the positive surfaces of heavy metal ions. In this study, epichlorohydrin was used as a crosslink to prepare the copper-imprinted chitosan as a pattern to enable the selectivity property and increase adsorption capacity. The effects of the cross-linker, PH, initial concentration and time were examined in this study to identify the optimum amount of each to remove copper metal ions from waste water by imprinted chitosan. This composite was characterized by Fourier-transform infrared spectroscopy (FTIR) test to determine the existence of copper ions in chitosan crosslinked with epichlorohydrin. Scanning electron microscopy (SEM) tests were also done to compare the surfaces of crosslinked chitosan and the removal of copper by imprinted chitosan. PH adsorption was tested from 3 to 7 and the initial concentration and time investigated were between 10 and 100 mg/l and 0 and 120 minutes respectively. The maximum capacity to adsorb was found to be at PH 7, initial concentration of 100mg/l at 90 minutes with 0.1 gr chitosan. Ultimately, the maximum adsorbent amount achieved for effective Cu(II) removal was 74.37 mg/g
Hydrodynamics study of gas hold-up and bubble rise velocity in quadrilateral bubble column at different superficial gas velocity and sparger design
This project is motivated from the difficulties in understanding the complexity of the fluid dynamics of gas-liquid in bubble column reactor mainly in industrial processes. Numerical simulation on multiphase models is the best method for fluid dynamics investigations. CFD analysis is useful for understanding multiphase reactors for precise design and scale-up. To ensure the success of the simulation technique, a complete description of the actual system developed is outlined including details of parameters used and data acquisition aspects. Multiphase model use resolves the time-dependent, three-dimensional motion of uniform size of gas bubbles in liquid using ANSYS CFX 14.0 software. A standard k-ε model is used to describe turbulence occurring in the continuous fluid. Experimental data from bubble column with a ratio of height to column diameter of 10 : 1 are compared with numerical model of bubble column with ratio of 5 : 2 with two different types of sparger design will be optimized. For this study, the spargers are tested for three different value of superficial gas velocity of 0.0125 m/s, 0.0501 m/s and 0.0627 m/s. Each spargers design was modelled to provide sufficient mixing in the reactor for scale-up purposes. In addition to enhancing technical understanding, the validation of the models was applied and the comparison with numerical technique will improve the accuracy in analyzing the hydrodynamics of multiphase system
Benefit of lactose concentration between goat’s milk and commercialized powder milk
Even though goat’s milk naturally has lower lactose than cow’s milk (~4.39% compared to 4.51%), when it's consumed in a large amount, those intolerant to lactose may suffer several inconvenient symptoms, such as bloating, nausea, and diarrhoea. Previous study had established that a high level of lactose removal from goat’s milk could be attained by 10 KDa sized ultrafiltration (UF) membrane. Hence, the concentrated goat’s milk obtained from the UF process and five local brands of commercial milk powder were compared in terms of nutrition facts. Lactose concentration as important nutrition is evaluated for the quality and the competitiveness between the products. While, proximate analysis was used as part of method to determine the chemical composition in the goat’s milk, including moisture, protein, fat, ash, and carbohydrate. Then, the composition of the reconstituted concentrated powder milk and five others commercialized milk which homogenized with water was analysed by HPLC to determine the lactose concentration. As a finding, concentrated milk contained 5.63 g per 100 ml lactose concentration, which ranked at the second lowest concentration in the range of 2.81 to 7.91 g per 100 ml, proved that it is similar and comparable in standard as to
commercial milk
Review on micro-encapsulation with chitosan for pharmaceuticals applications
There is evidence that several systematic researches recognized the importance of using polymers in drugs manufacturing. Natural polymers are usually biocompatible, biodegradable and non-expensive like chitosan. Chitosan is one of the natural biodegradable groups of polymers that have been extensively used for microencapsulation of drugs like isoniazid, propranolol and aspirin. This natural polysaccharide has many pharmaceuticals
applications, such as oral and parenteral delivery of drugs. It is important for a wide range of scientific and industrial processes to know the applications of chitosan microparticles loaded drugs in pharmaceuticals fields. Recently, this issue was the objective of many research papers in the literature. Chitosan can also be combined with other polymer to encapsulate many drugs in order to achieve targets with performance delivery. Recent advances in microencapsulation methods have facilitated investigation of chitosan usage to load drugs. This review about the preparation of chitosan-based-micro and particles by many fabrications methods of pharmaceutical applications including coacervation, drying techniques, ionic cross-linking, ionotropic gelation and emulsion solvent diffusion method
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