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Helium is a non-renewable resource that is obtained from natural gas. The recent increase in the wholesale price of He has focused attention on exploiting low grade reservoirs. Cryogenic liquefaction for He recovery becomes increasing energy intensive as the feed He concentration decreases. Hence, alternative separation technologies are required and membrane gas separation has potential. Here, membranes are simulated for the recovery of He for a range of feed gas compositions. A cellulose acetate membrane is the focus, with simulations indicating that for a feed with less than 3 mol% He, a three-membrane stage cascade process is viable. The energy duty of the process increased with reduced He concentration, but this increase in energy duty is less than that observed for cryogenic liquefaction and below a feed concentration of 2.5 mol% He, the membrane process is energy competitive. Hence, membrane gas separation has potential for He recovery from natural gas. [ABSTRACT FROM AUTHOR]

The wastewater discharged by cheese manufacturing processes is highly saline. This waste is generated from whey demineralization, chromatography and clean-in-place processes. Salty effluent can be diluted with other effluents and discharged as trade waste but the high salinity can trigger penalties imposed by local water authorities. Alternatively, such waste can be sent to evaporation ponds, but in some areas in Australia, environmental impacts regarding land degradation, odor and dust have prevented further pond construction. Similar concentrate and brine management issues are emerging in the seawater desalination and mining industries. This paper reviews a range of commercial and emerging separation technologies that may be suitable to both reduce the costs of salty wastewater treatment and to improve the recoveries of dairy and salt-based products. These technologies have been commercialized or applied at a laboratory scale to the fields of desalination and brine concentration. Each technology is discussed in terms of its principle of operation and suitability for treating high-salinity dairy wastewater. The potential energy requirement and processing cost of each technology is identified with respect to feed water salinity, to provide additional insights into the energy and cost efficiencies of these technologies. [ABSTRACT FROM AUTHOR]

Separating global horizontal irradiance measurements into direct and diffuse components has been vigorously discussed over the past half-century of solar radiation research leading to the creation of many models which attempt to compute these components with varying degrees of success. However, over the course of this discussion, nearly all studies have focused on hourly values, with no studies that have proposed a model for minute-level values of irradiance. As data-logging technologies have become much more prolific and their storage capabilities much larger, solar radiation monitoring sites are more commonly logging data at intervals much less than one hour, but no models exists that are designed to separate these measurements into direct and diffuse components. In Australia, the Australian Bureau of Meteorology and the Australian Solar Institute have compiled a dataset of tens of millions of one-minute global, direct and diffuse solar irradiance observations, comprising data from regions all around Australia. This dataset provides a unique opportunity to investigate the relationships between global irradiance and its direct and diffuse components at higher resolution than has previously been possible. Herein, the largest and most complete diffuse fraction model analysis yet undertaken for Australian solar radiation data, and the first ever to focus on minute resolution data is reported. Nine of the most prominent diffuse fraction, or “separation”, models are tested against minute resolution radiation data from three datasets. The first removed cloud enhancement events in accordance with practices undertaken by the majority of studies in the literature. The second retains these events in order to assess which model would be best suited for operational purposes. The third consisted of only clear sky observations, in order to assess the performance of diffuse fraction models under clear skies. Through the course of this study only the Perez model was found to perform satisfactorily for minute resolution data at sites in southeastern Australia. Three new diffuse models proposed in this study, one trained for each of the three datasets, were found to greatly exceed the performance of existing modeling techniques, with slight improvements over the Perez model. [ABSTRACT FROM AUTHOR]

In this study, the most appropriate organic phase for the selective extraction of Zn(II) from Australian hot-dip galvanizing effluent streams has been determined. TBP (tributyl phosphate) and Hostarex A226 (diisotridecylamine) were identified as the most favourable for the extraction of zinc ions from a chloride matrix. Two alternatives, Hostarex A324 (tri-iso-octlyamine) and Hostarex A327 (tri-n-octyl/n-decylamine), were also tested. Laboratory scale shake tests were conducted using model solutions containing a range of acid concentrations and zinc concentrations up to 80 g/L. Industrial pickling effluent was used to test the effect of impurities present. The use of TBP was confirmed as the most appropriate extractant. [ABSTRACT FROM AUTHOR]

Abstract: A pilot-scale flotation apparatus has been developed for the purpose of determining floatability parameters for an ore. It has the capability to vary many of the important flotation variables allowing them to be investigated independently. Adjustable factors include: cell size, froth depth, feed, tailings and air volumetric flow rates and reagent addition rates. The flotation rig was commissioned successfully at BHP Billiton’s Cannington mine in North-West Queensland, Australia. It was found to supply a stable feed stream with air well distributed across the cell. At the test conditions, the relative standard deviation of the calculated galena overall recovery was found to be only 1%. Such an apparatus could prove invaluable in flotation research, allowing live streams from an operating industrial flotation plant to be processed continuously. The versatility of the design and accuracy of performance allow the investigation of most major flotation variables with confidence. [ABSTRACT FROM AUTHOR]

Abstract: In order to provide safe drinking water in isolated communities where water supply and electrical infrastructure is limited, a system combining solar energy and advanced water treatment technology (a two-staged membrane process with ultrafiltration followed by nanofiltration/reverse osmosis (NF/RO)) has been developed. The objective of this study is to model the speciation of commonly-occurring and sometimes health-threatening trace contaminants, and then to evaluate the impact of speciation on fluoride, arsenic, and magnesium retention by NF/RO. A series of experiments were performed in central Australia in late 2005 to assess elemental retention with four different membranemodules (BW30, ESPA4, NF90, and TFC-S) at various pH values between 3 and 11 at two different source waters (Pine Hill Station and Ti Tree Farm). The removal of fluoride and arsenic was observed to be independent of pH, while magnesium removal is pH dependent. Compound speciation is considered to explain dependence observations. Membrane type was found to impact retention. The results obtained in this study will provide valuable information on the reliability and the optimization windows of the renewable energy powered desalination system that has been developed. [Copyright &y& Elsevier]

The gas-induced swelling behavior of coal is important when considering CO2 sequestration into coal seams or enhanced coalbed methane applications, but coals may also swell in the presence of moisture, or shrink on drying. In this paper we examine the moisture-swelling properties of coals from Australia and elsewhere. Results on the moisture uptake and corresponding swelling measurements are presented for 15 coals of various ranks (sub-bituminous and bituminous) at 22°C and atmospheric pressure. Measurements were made by exposing sample blocks of coal (nominally 30 × 10 × 10 mm) to relative humidities ranging from 0% to 97%. A selection of coals was also fully saturated in water. Moisture uptake at 97% relative humidity (RH) ranged from about 2.5% to more than 16% db. Maximum linear strain associated with the moisture sorption (measured at 97% RH) varied from about 0.2% to 1.3%, with lower rank coals showing the most swelling. In all cases, swelling was greater in the direction perpendicular to the bedding plane. These results correspond to volumetric swelling of about 0.5% to around 5%. Although exhibiting significant expansion, all of the samples returned to their original dimensions upon drying. Volumetric moisture sorption and the amount of swelling induced were found to be strongly correlated by a single linear expression that held for all of the coals examined. It was further found that the volume of the water adsorbed was linearly related to the pore space within the coal, however, at 97% relative humidity, only about 60% of the available pore space is occupied by water. Exposure to liquid water allowed the pores to completely fill; although for the lowest rank coals, the volume of water absorbed appeared to be slightly more than the corresponding pore volume. Despite the additional water uptake, immersion in water did not produce further swelling beyond that induced at 97% relative humidity. [ABSTRACT FROM AUTHOR]

The article discusses the two approaches to develop tools that aid phosphorus (P) releases from Australian or New Zealand diary farms. It states that the approach is mixed with possible point sources and adept cognition of hydrological processes to make a model that can be used to examine the cost and labor capable method of lightening P releases. Whereas, the second approach uses a collection of adept knowledge and interviews to formulate a Bayesian Network that illustrates P releases. It notes that the idea of the integration process may aid shareholders improve an inclusive comprehension of the problem. The Network is introduced in the form of a cause and effect diagram that offers visual representation of existing knowledge which can isolate factors having influences of P releases.

An assessment of potential health impacts of radioactive compounds in recycled water to augment drinking water supplies was conducted. Gross alpha and gross beta particle activity was selected for the screening of radioactive species. Samples both pre- and post-reverse osmosis treatment of secondary effluent in Perth, Australia were examined in both a full-scale and in a pilot water reclamation plant. Risk quotients (RQs) were estimated by expressing the mean (RQ mean) and the maximum concentration (RQ max) at each sampling point as a function of the recommended Australian screening levels of 0.5 Bq/L. The results indicate that reverse osmosis (RO) is able to reduce the concentration of gross alpha particle activity (average removal of almost 80%) and gross beta particle activity (average removal of 95%) and produce water of high quality. Maximum gross alpha particle activity in the recycled water was 0.023 Bq/L and maximum gross beta (excluding 40K) particle activity was 0.03 Bq/L, which correspond to an RQ max of 0.07 for gross alpha and 0.06 for gross beta particle activity, respectively. No increased human radiological risk is anticipated if recycled water is used to augment drinking water supplies in Perth. [ABSTRACT FROM AUTHOR]

Abstract: Century Mine, operated by Zinifex, is one of the largest zinc and lead deposits in Australia. The ore contains sphalerite and galena as valuable minerals, and carbonaceous material is present among the gangue minerals. The presence of carbonaceous matter is detrimental to the concentration of zinc and lead by flotation. Therefore, preflotation, which is flotation in the absence of collector and prior to galena flotation, is employed to remove some of the organic carbon, some of which is naturally hydrophobic, from the flotation feed. The main issues affecting the effectiveness of preflotation are: (i) low carbon recovery, (ii) low selectivity against zinc, and (iii) very high frother (methyl isobutyl carbinol, MIBC) consumption. The present study revealed that: (a) most of the MIBC added during flotation disappears from solution due to its high adsorption onto ore particles and especially on fine carbon enriched particles which have high surface area, (b) the addition of diesel oil can reduce MIBC consumption by 50% (in laboratory flotation tests) and (c) polypropylene glycol (PPG 192) showed lower affinity for carbon surfaces due to this reagent’s higher hydrophilic/lipophilic balance, producing stable froths at 50% of the current MIBC addition. [Copyright &y& Elsevier]

Projections of world energy demand indicate increasing use of fossil fuels, especially coal. Because of this there is interest in using carbon dioxide capture and storage technologies as a mitigation option, particularly in Australia because of its dependency on fossil fuels for electricity generation. Research in Australia into capture options includes post‐combustion capture (PCC), integrated gasification combined cycle (IGCC) and oxyfuels combustion. Separation technologies being investigated in Australia include solvent absorption, membranes, adsorption and cryogenics, with particular emphasis on bringing down costs. Australia appears to have abundant geological storage capacity, particularly in saline formations and to a much lesser extent in depleted oil and gas fields. Storage in coal systems has potential but more research and development is needed. Australia has the opportunity to use low‐emission hubs in order to bring down costs. A major study of this concept for the Latrobe Valley of Victoria, based on 50 million tonnes per annum of CO2 emissions, is encouraging. A key concept for taking CO2 capture and geological storage forward is demonstration and commercial deployment. Australian projects are proposed for PCC and oxyfuels combustion. A significant geological storage project has started in the Otway Basin, with CO2 injection scheduled to commence in mid‐2007. The coal‐to‐liquids Monash Project could involve up to 10 million tonnes CO2 per annum, with injection into the offshore Gippsland Basin. The most advanced commercial project is the LNG Gorgon Project, comprising about 3 million tonnes per annum. Through current R&D momentum and the likelihood of a number of major commercial‐scale projects, Australia could become an early mover in the application of carbon dioxide capture and geological storage. [ABSTRACT FROM AUTHOR]

Much of the natural gas consumed in Australia comes from reservoirs near the middle of the country. To take advantage of higher-priced liquid components, from 1980 to 1984 producers spent $A1.4 billion on plant to separate gas and liquids and a 500-mile liquids pipeline. The sequence of investments in producing facilities and the gas production schedule that maximize net present value over a 25-year horizon are determined with a nonlinear, decomposition-based, mathematical programming system, called SIPS, which uses a tailored reservoir simulation model to accurately predict reservoir decline. In annual planning we estimate that SIPS saves about 10 percent of the investment it considers, or $A3-6 million per year. SIPS's answers to what-if questions may yield equivalent benefits, and its impact may be much greater in such areas as gas price negotiations, responses to legislated changes in South Australian energy policy, the payment schedule for the project's loan, the optimal response to the recent collapse in oil prices, and participation factors for each of the 11 companies sharing costs and revenues in the Cooper Basin. [ABSTRACT FROM AUTHOR]

Scientists in Australia have completed initial research on specially designed ceramic membranes that have the potential to remove viruses from water, air and blood. They say, as this brief feature shows, that membrane technology could play an important role in saving the lives of millions of people. [Copyright &y& Elsevier]

Australia is the world''s driest inhabited continent and Queensland is the country''s second highest per capita water user. The region''s current severe drought conditions and forecasting research, suggesting a weather trend of even longer dry spells, paint a dry picture of the state''s future. Here, we look at how membrane technology is helping to relieve the region''s water crisis. [Copyright &y& Elsevier]

Australian desalination company Osmoflo Pty Ltd reports that its contract option, which enables customers to rent reverse osmosis (RO) desalination infrastructure for short-term water needs, is proving to be particularly popular with companies in the resources sector. [Copyright &y& Elsevier]

The 6th International Membrane Science and Technology Conference, IMSTEC 07, is scheduled to be held at the University of New South Wales (UNSW), Sydney, Australia on 5–9 November 2007. [Copyright &y& Elsevier]