REAL WORLD FUEL WATER SEPARATION PERFORMANCE
Mark Wieczorek, Barry Verdegan and Eric Quillen (pages 21-25)
Industrial test standards facilitate comparisons of fuel water separator performance for different products under repeatable and reproducible conditions. They do not, however, simulate field conditions nor do they reflect actual field performance. These standards do not necessarily provide meaningful differentiation in terms of performance among different products. In the worst case, industrial standards may produce a false sense of security for filter users. These issues are recognised by the filtration industry. Revisions to the standards at SAE and ISO are in process to enable performance assessment under more repeatable and realistic conditions. Despite this, the end of life performance of fuel water separators remains largely ignored.
In this paper, the end of life performance of several commercially available fuel water separators was evaluated using the SAE J1488 fuel water separation test method. The separators are representative of filters on the market that exhibit >95% efficiency when new. From the results, the importance of considering end of life performance, as well as initial performance, is clear. The results also suggest shortcomings of current industrial test standards for fuel water separator testing and may provide guidance to standards organisations.
MEMBRANE TECHNOLOGY – PAST, PRESENT & FUTURE WITHIN THE WATER INDUSTRY
Thomas Peters (pages 26-31)
The pressure driven membrane processes of microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) have become definitively important instruments in water management and environmental engineering. Their performance has been comprehensively verified from a technical and economical, as well as an ecological, point of view. These processes can be considered nowadays to be well-proven and very successful tools of chemical engineering, allowing, for example, to overcome water scarcity and to prevent water pollution, or to enable recovery and reprocessing of valuable substances. In combination with other processes the remaining water quantity can be significantly reduced by multiplied usage of the water, thus saving costs, but also facilitating the realisation of environmental sustainable zero liquid discharge (ZLD) procedures.
This development is partially based on results obtained during the operation of RO systems that were designed in the early days of the technology for the desalination of seawater (trendsetting patent 1964). Details addressing these membrane processes, examples of their area of application in the past, present and expected developments, are considered for the discussion of decision supporting criteria for the selection of these technologies.
WATER REMOVAL APPLICATIONS OF AN INNOVATIVE COALESCER ELEMENT IN MINERAL LUBRICATING OILS
Ruijun Chen (pages 31-39)
The requirement to remove water contamination in mineral lubricating oil is particularly stringent, since the presence of even a small amount of water contamination can cause numerous problems affecting thermal oxidation stability, lubricity, filterability, corrosion and equipment service life. To effectively and efficiently removewater contamination dispersed in mineral lubricating oil a new coalescer element is studied in this paper. Water contamination issues are briefly introduced, the unique coalescence mechanism occurring in an innovative coalescing media SFM is proposed and the conceptual design of the new coalescer element is presented. A laboratory test stand and oil analysis procedure are also described.
The results from preliminary water removal tests with ISO 32 and ISO68 mineralturbine lube oils demonstrate the performance of the new coalescer element. For example, within a single flow pass through the new coalescer element and then one commercial K3100 separator element at flow rates up to 10 GPM, the water content in 75ºF ISO32 mineral turbine lube oil stream can be reduced from up to 5 vol% upstream to 41 ppm or less downstream.
EFFECT OF SILICON FINISH ON THE BEHAVIOUR OF REGENERATED SURFACE FILTERS AT DIFFERENT DUST CONCENTRATION
ArunangshuMukhopadhyay and SoumyaRanjan Swain (pages 40-47)
This paper discusses the effect of two different filter media, viz. polyester filter fabric treated with silicone finish and polyester fabric filter without treatment, and two different dust concentrations (50 and 90 g/m3) on the performance of pulse-jet filtration. The fabrics were tested based on cleaning at fixed peak pressure drop for an equal number of test cycles during the first three phases (i.e. conditioning, ageing and stabilising) and for the same time duration during the final measuring phase. Silicone treated filter fabric showed better filtration efficiency compared to untreated fabric. At higher dust concentration, the reduction in efficiency was much lower in the case of the treated filter. A light scattering aerosol spectrometer system was used for analysing the emitted particles from the filter media. Particulate parameters like PM2.5 and PM10 emissions, number concentration and mass concentration of particles were less for the treated filter fabric.
After the ageing process, the silicone treated filter showed a smaller rise in pressure drop compared to the filter without treatment. The silicone treated fabric also showed more or less the same pattern of particle size distribution for emitted particles when tested at both higher and lower dust levels, but for the untreated fabric the distribution curve was much broader at the lower dust concentration. However, the difference in the particle size distribution pattern of emitted particles was marginal among the two fabrics when tested at a higher dust concentration. Experimental work was also carried out by analysing the residual pressure drop pattern with time for both fabric types, but no clear pattern was observed for the residual pressure drop. It was found that the treated fabric showed more predictable results compared to the untreated fabric.
THE INFLUENCE OF IONIC STRENGTH ON THE LOCAL FILTRATION PROPERTIES OF TITANIUM DIOXIDE
TuveMattsson, Julie Durruty, Jonas Wetterling and Hans Theliander (pages 48-57)
Deadend filtration is an energy efficient way of achieving solid-liquid separation. It is used in a wide variety of industrial processes and for materials having very different properties. Development of accurate models describing the filtration properties of a material in terms of particle and suspension properties is important and would be of great use in, for example, process design and troubleshooting.
The aim of this study is to investigate the effects of particle interactions on local filtration properties. Titanium dioxidewas used as a model material and the electrostatic interactions between the particles were altered by changing the ionic strength of a suspension. At low ionic strengths the repulsive electrostatic forces between particles prevented agglomeration, and the filter cakes formed had a low compressibility. As the ionic strength of the suspension was increased, the particles agglomerated more extensively and a more porous structure of the filter cake was obtained. It was found that the decrease in the inter-particle repulsive forces resulted in the formation of filter cakes with a lower solidosity, lower specific filtration resistance and higher compressibility. Finally, three filtration models were applied and could successfully describe the relationship between the local solidosity and the local specific filtration resistance of a filter cake.
COMPARING ADSORPTION OF BISPHENOL A AND SIMILAR COMPOUNDS IN AQUEOUS SOLUTION BY SYRINGE FILTERS
Nathaniel Godby (pages 57-60)
Analyte loss during syringe filtration is often overlooked in quantitative analyses. Bisphenol A, and similar compounds, are being extensively examined for their toxicity. This study serves to characterise common syringe filters and their effects on analytical results. The adsorbance of bisphenol A and similar compounds by filter media made from cellulose acetate, nylon, and polytetrafluoroethylene (PTFE) was examined using UV-Vis spectroscopy. Samples of Bis(4-hydroxydiphenyl)methane (BPF), Bis(4-hydroxyphenyl)sulfone (BPS), 2,2-Bis(3-methyl-4-hydroxyphenyl)propane (BPC), 4,4’-(propane-2,2-diyl)diphenol (BPA), 4-cumylphenol, and phenol were studied. Solutions were analysed before and after filtration. Filter composition significantly affected analyte concentrations in the filtrate solutions.