Papers by Keyword: Filtration

Abstract: The process of silicon carbide producing (SiC) in a resistance furnace is accompanied by moisture movement in the batch. An important consideration is the accounting of moisture transfer in the preparation of the mathematical description of the process. The aim of the article is to improve the existing model of heat and mass transfer in SiC production.

Abstract: The rapid development of advanced technology in Thailand has resulted in an increased impact from micro-pollutant accumulation through wastewater. Phenolic compounds, generally originating from synthetic and plastic products, have been frequently detected in industrial and municipal wastewater. Releasing these compounds into the environment affects the human body at trace levels. In terms of economic perspective and environmental considerations, filtration is an appropriate process for wastewater treatment. In this research, filtration material made from eggshell ash was investigated for organic micro-pollutant removal. The mechanical strength of the derived filtration materials was evaluated in terms of compressive strength. For the fabrication process, the different proportions were composed in a range of 45% – 55% of eggshell ash. Eggshell ash contents could increase the porosity of the filtration specimen by heat at a temperature of 750 °C. The removal efficiency of filtration material approximately more than 80%. The ratio of 55% of eggshells showed better results with permeability value of 57±3.5 L/m²/h and compressive strength of 5.25 MPa.

Abstract: In light of urgent requirement of onboard ballast water treatment, a novel wall-flow structure porous ceramic filter (PCF) has been applied with combination of UV light in our laboratory works. According to the strict criteria of International Maritime Organization (IMO) on ballast water treatment, removal efficiencies on indicator planktons should be almost 100% even at high initial densities. However, the treatment efficiencies of PCF may be greatly affected by operational conditions of the system. Hence response surface methodology (RSM) was used to evaluate the significance of the operational factors on algal removal efficiencies. Based on our previous works, flow rate, algal density and algal size were considered as three key conditional factors during PCF treatment. These three individual factors and interactive effects between each two facts were studied statistically by Minitab 15. Also, experimental studies were arranged according to full factorial design of a 6L PCF on simulated ballast water treatment at different flow rates, algal densities and algal sizes. By computational prediction and mathematical analysis, the operational conditions were optimized with first order derivation of predicted model. And by doing so, the utmost optimization was estimated to achieve higher performance of PCF system.

Abstract: As for gasoline vehicles, the particulate matter (PM) emissions from traditional port fuel injection (PFI) engines are pretty low. Recently, the gasoline direct injection (GDI) vehicles have been gaining market share globally due to better fuel efficiency, especially in the European countries. A drawback associated with GDI engines is considerably higher PM emissions compared with PFI engines. The soot in gasoline exhaust gas would contribute to urban air pollution, which is deeply related with adverse health effects. For the reduction of PM emission in Europe, a new regulation known as EURO VI has been set recently. Then, we need to trap soot particles in exhaust gas from gasoline automobiles as well as diesel automobiles. However, the gasoline soot would be much smaller than the diesel soot. Also, the gasoline exhaust gas temperature is much higher. Then, we need gasoline particulate filter (GPF) which needs to have better thermal durability. In this study, as a potential GPF, an SiC fiber filter was numerically examined. The effect of the fiber diameter on the filtration was revealed. Results show that, when the filter of the larger fiber diameter is placed more upstream, the deposition of soot particles widely occurs inside the filter, resulting in the lower pressure drop.

Abstract: In this work, we introduce a synthesis method for a nanofiber membrane made of polyacrylonitrile and verify its filtration ability with micron-size particles. The polyacrylonitrile nanofiber membrane was produced by electro-spun technique with a thickness less than 0.2 mm. The filtration experimental result from micron-size particle penetration proved that after 60-min deposition, the polyacrylonitrile nanofiber membrane successfully filtrated ~99% micron-size particles in solution. We found that uniform morphology, consistent nanofiber diameter without disordered beads will lead to a better filtration performance. This finding will provide a low-cost, environmental-friendly and straightforward filtration approach for future PM_2.5 elimination in an aqueous and harsh environment.

Abstract: In clay suspensions designed for drilling, the sodic bentonite clay is commonly chosen for its better hydration capacity compared to the other kinds. The sodium bentonite clay is essentially composed by montmorilonite, a clay mineral that belongs to the group of smectites. This work aims to evaluate the behavior of clay suspensions under different thermic conditions. For that, were studied suspensions prepared with sodium bentonite clay, in concentrations varying between 2.5% and 6.4%, under different temperatures and also types of aging. The suspensions were tested based on a matrix of experimental planning. The filtration properties were determined by the filtrate volume, the relation of filtrate volume with time of filtration, the mudcake thickness and the permeability of the mudcake. The results exhibited that the high temperature promotes a gelification state of the suspensions, being therefore responsible for the high values of the filtration properties.

Abstract: The paper presents the study on the physical properties of the cuttings. Culvert capacity of the drill cuttings with different coagulants is considered. The water permeability of the studied samples varies depending on the quality of the composition and the dosage of a coagulant used. The coagulants have been proposed as aluminium sulphate, iron sulphate, calcium chloride, gypsum, phosphogypsum, serpentine, blast furnace slag, calcium carbonate and carnallite. Iron and aluminium sulphates, calcium chloride, gypsum and phosphogypsum appear to be the most effective when acting on the water permeability in the drill cuttings. With regard to the variants incorporating the complete response curve, the optimal dose of ameliorant can be determined after maximum filtration of water in the column. This method allows the dose of coagulant to be determined by the filtration threshold. The optimal dose for iron sulphate is 0.8 g; with this parameter the volume of filtered water reaches 16.80 ml / day.The use of effective coagulants allows displacement of sodium and potassium cations from the absorption complex and fundamentally improves its physical and chemical properties; this is clearly seen by the change of the filtration capacity of the considered sample. Phosphogypsum – a waste material of chemical industry of Ural chemical plants - is of the greatest interest. It can significantly improve the properties of the considered sample when transforming two waste materials (drill cuttings and phosphogypsum) to a neutral environmentally-friendly state.

Abstract: Due to the increase of industrial activities both at local and national level, the quality of water in Indonesia is significantly degraded by time. Heavy metal wastes from industrial activities have become serious contaminants in the water. The contamination dangers human’s health since most people living near the river-bank still use the water to fulfill their daily needs. In this paper, we present the fabrication of Hydroxyapatite (HA) disc as a filtration medium in waste water treatment system. HA is one of biomaterial which can be derived from animal’s bone and is capable to absorb dangerous heavy-metal contaminants such as lead (Pb) in the water. Our produced HA was made by extracting cortical bovine bones into cortical bone HA powder. The cortical bovine bones were processed using physical method by heating the bones at 900oC to gained powder then followed by forming green bodies and sintering at 1000oC and 1400oC. Those powders were then pressed into a disc form and will be used as filtration media in HA modular purifier. SEM/EDX results show the disk surface has interconnected micropores and Ca/P ratio value on sintered HA disc at 1000oC and 1400oC are 2.20 and 1.85, respectively.

Abstract: This paper, with fractional calculus theory and Maple as tools, takes cigarettes as porous media to establish a fractional model describing filtration effect of cigarette filter tip, and explains the relationship between the functions of filter tip and filter materials, and reveals the relationship between the role of filter tip and the filter length. The results show that the improvement of the absorption rate of toxics and increasement of filter length can exponentially improve the filtering effect. Moreover, the speed lowering of the smoke smog spreading can also improve the filtering effect.

Abstract: During oil wellbore drilling processes, filter cake is formed on the sidewalls of the well hole due to filtration of drilling fluid particles. The filter cake is crucial to the drilling process, since it helps to maintain the wellbore hole, protects the drilling bit from jamming and facilitates the subsequent phases of the well development. The most important parameter for filter cake formation is its thickness and its variation due to drilling conditions. In this paper, the drilling fluid particles filtration process was simulated at conditions mimicking deep wellbore drilling. The drilling fluid was simulated as a non-Newtonian two-phase fluid of liquid and particles, utilizing an Eulerian-Eulerian approach. The model successfully predicted a filter cake thickness which agrees well with measurements and previous CFD work.