Environmental studies plan /

Mode of access: Internet.

The design of offshore drilling structures.

"Paper no. 54-Pet-19 for presentation at the ninth annual Petroleum Mechanical Engineering Conference, Los Angeles, California September 27-29, 1954. American Society of Mechanical Engineers."

Oil, paint and drug reporter.

Vols. include the proceedings (some summarized, some official stenographic reports) of the National Wholesale Druggists' Association (called 18 -1882, Western Wholesale Druggists' Association) and of other similar organizations.

Fuel cells, hydrogen and energy supply in Australia

Australia is unique in terms of its geography, population distribution, and energy sources. It has an abundance of fossil fuel in the form of coal, natural gas, coal seam methane (CSM), oil, and a variety renewable energy sources that are under development. Unfortunately, most of the natural gas is located so far away from the main centres of population that it is more economic to ship the energy as LNG to neighboring countries. Electricity generation is the largest consumer of energy in Australia and accounts for around 50% of greenhouse gas emissions as 84% of electricity is produced from coal. Unless these emissions are curbed, there is a risk of increasing temperatures throughout the country and associated climatic instability. To address this, research is underway to develop coal gasification and processes for the capture and sequestration Of CO2. Alternative transport fuels such as biodiesel are being introduced to help reduce emissions from vehicles. The future role of hydrogen is being addressed in a national study commissioned this year by the federal government. Work at the University of Queensland is also addressing full-cycle analysis of hydrogen production, transport, storage, and utilization for both stationary and transport applications. There is a modest but growing amount of university research in fuel cells in Australia, and an increasing interest from industry. Ceramic Fuel Cells Ltd. (CFCL) has a leading position in planar solid oxide fuel cells (SOFCs) technology, which is being developed for a variety of applications, and next year Perth in Western Australia is hosting a trial of buses powered by proton-exchange fuel cells. (C) 2004 Elsevier B.V. All rights reserved.

Numerical analysis of gas and micro-particle interactions in a hand-held shock-tube device

A unique hand-held gene gun is employed for ballistically delivering biomolecules to key cells in the skin and mucosa in the treatment of the major diseases. One of these types of devices, called the Contoured Shock Tube (CST), delivers powdered micro-particles to the skin with a narrow and highly controllable velocity distribution and a nominally uniform spatial distribution. In this paper, we apply a numerical approach to gain new insights in to the behavior of the CST prototype device. The drag correlations proposed by Henderson (1976), Igra and Takayama (1993) and Kurian and Das (1997) were applied to predict the micro-particle transport in a numerically simulated gas flow. Simulated pressure histories agree well with the corresponding static and Pitot pressure measurements, validating the CFD approach. The calculated velocity distributions show a good agreement, with the best prediction from Igra & Takayama correlation (maximum discrepancy of 5%). Key features of the gas dynamics and gas-particle interaction are discussed. Statistic analyses show a tight free-jet particle velocity distribution is achieved (570 +/- 14.7 m/s) for polystyrene particles (39 +/- 1 mu m), representative of a drug payload.

Hydrogen from coal: Production and utilisation technologies

Error condition detected Although coal may be viewed as a dirty fuel due to its high greenhouse emissions when combusted, a strong case can be made for coal to be a major world source of clean H-2 energy. Apart from the fact that resources of coal will outlast oil and natural gas by centuries, there is a shift towards developing environmentally benign coal technologies, which can lead to high energy conversion efficiencies and low air pollution emissions as compared to conventional coal fired power generation plant. There are currently several world research and industrial development projects in the areas of Integrated Gasification Combined Cycles (IGCC) and Integrated Gasification Fuel Cell (IGFC) systems. In such systems, there is a need to integrate complex unit operations including gasifiers, gas separation and cleaning units, water gas shift reactors, turbines, heat exchangers, steam generators and fuel cells. IGFC systems tested in the USA, Europe and Japan employing gasifiers (Texaco, Lurgi and Eagle) and fuel cells have resulted in energy conversions at efficiency of 47.5% (HHV) which is much higher than the 30-35% efficiency of conventional coal fired power generation. Solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC) are the front runners in energy production from coal gases. These fuel cells can operate at high temperatures and are robust to gas poisoning impurities. IGCC and IGFC technologies are expensive and currently economically uncompetitive as compared to established and mature power generation technology. However, further efficiency and technology improvements coupled with world pressures on limitation of greenhouse gases and other gaseous pollutants could make IGCC/IGFC technically and economically viable for hydrogen production and utilisation in clean and environmentally benign energy systems. (c) 2005 Elsevier B.V. All rights reserved.

Factors affecting hot spot development in bulk coal and associated gas evolution

There are many physical factors that can affect the self-heating rate of coal. The presence of seam gas has often been referred to as inhibiting coal self-heating due to the limited access of oxidation sites created by the presence of the gas adsorbed on the coal pores. Similarly, the presence of bed moisture in the coal also acts as an inhibitor of oxidation by blocking access of air into the pores. Gas drainage of a coal seam prior to mining removes both gas and moisture from the seam. Bulk coal self-heating tests in a two-metre column on both gassy, as-mined and gas-drained, dried high volatile bituminous coal show that removal of gas and moisture from the coal accelerates the rate of self-heating to thermal runaway from 8.5 days to 4.25 days, from a start temperature of 30°C, with an airflow of 0.25 L/min. The corresponding gas evolution pattern for each of these situations is different. Therefore, it is necessary to take this change in coal condition into consideration when developing a spontaneous combustion management plan.

Preparation and characterization of mesoporous Ni/Zr-laponite for the catalytic deoxygenation of vegetable oils into liquid hydrocarbons

The deoxygenation of vegetable oils was studied over a Ni/Zr-laponite catalyst in various nickel loading composition. Stearic acid has been used as a model compounds. The liquid and gas products were analyzed using gas chromatograph equipped with thermal conductivity detector and flame ionization detector. From product distribution it was determined the effect of catalyst composition on reaction conditions

Upgrading fast pyrolysis liquids:blends of biodiesel and pyrolysis oil

Fast pyrolysis liquid or bio-oil has been used in engines with limited success. It requires a pilot fuel and/or an additive for successful combustion and there are problems with materials and liquid properties. It is immiscible with all conventional hydrocarbon fuels. Biodiesel, a product of esterification of vegetable oil with an alcohol, is widely used as a renewable liquid fuel as an additive to diesel at up to 20%. There are however limits to its use in conventional engines due to poor low temperature performance and variability in quality from a variety of vegetable oil qualities and variety of esterification processes. Within the European Project Bioliquids-CHP - a joint project between the European Commission and Russia - a study was undertaken to develop small scale CHP units based on engines and microturbines fuelled with bioliquids from fast pyrolysis and methyl esters of vegetable oil. Blends of bio-oil and biodiesel were evaluated and tested to overcome some of the disadvantages of using either fuel by itself. An alcohol was used as the co-solvent in the form of ethanol, 1-butanol or 2-propanol. Visual inspection of the blend homogeneity after 48 h was used as an indicator of the product stability and the results were plotted in a three phase chart for each alcohol used. An accelerated stability test was performed on selected samples in order to predict its long term stability. We concluded that the type and quantity of alcohol is critical for the blend formation and stability. Using 1-butanol gave the widest selection of stable blends, followed by blends with 2-propanol and finally ethanol, thus 1-butanol blends accepted the largest proportion of bio-oil in the mixture. © 2013 Elsevier Ltd. All rights reserved.

The effect of lignin and inorganic species in biomass on pyrolysis oil yields, quality and stability

This paper investigates four reference fuels and three low lignin Lolium Festuca grasses which were subjected to pyrolysis to produce pyrolysis oils. The oils were analysed to determine their quality and stability, enabling the identification of feedstock traits which affect oil stability. Two washed feedstocks were also subjected to pyrolysis to investigate whether washing can enhance pyrolysis oil quality. It was found that the mineral matter had the dominate effect on pyrolysis in compared to lignin content, in terms of pyrolysis yields for organics, char and gases. However the higher molecular weight compounds present in the pyrolysis oil are due to the lignin derived compounds as determined by results of GPC and liquid-GC/MS. The light organic fraction also increased in yield, but reduced in water content as metals increased at the expense of the lignin content. It was found that the fresh oil and aged oil had different compound intensities/concentrations, which is due to a large number of reactions occurring when the oil is aged day by day. These findings agree with previous reports which suggest that a large amount of re-polymerisation occurs as levoglucosan yields increase during the aging progress, while hydroxyacetaldehyde decrease. In summary the paper reports a window for producing a more stable pyrolysis oil by the use of energy crops, and also show that washing of biomass can improve oil quality and stability for high ash feedstocks, but less so for the energy crops.

Study on the pyrolytic behaviour of xylan-based hemicellulose using TG-FTIR and Py-GC-FTIR

Two sets of experiments, categorized as TG–FTIR and Py–GC–FTIR, are employed to investigate the mechanism of the hemicellulose pyrolysis and the formation of main gaseous and bio-oil products. The “sharp mass loss stage” and the corresponding evolution of the volatile products are examined by the TG–FTIR graphs at the heating rate of 3–80 K/min. A pyrolysis unit, composed of fluidized bed reactor, carbon filter, vapour condensing system and gas storage, is employed to investigate the products of the hemicellulose pyrolysis under different temperatures (400–690 °C) at the feeding flow rate of 600 l/h. The effects of temperature on the condensable products are examined thoroughly. The possible routes for the formation of the products are systematically proposed from the primary decomposition of the three types of unit (xylan, O-acetylxylan and 4-O-methylglucuronic acid) and the secondary reactions of the fragments. It is found that the formation of CO is enhanced with elevated temperature, while slight change is observed for the yield of CO2 which is the predominant products in the gaseous mixture.

Flowback of solids through distribution plates of gas fluidized beds and associated phenomena

This work is concerned with a study of certain phenomena related to the performance and design of distributors in gas fluidized beds with particular regard to flowback of solid particles. The work to be described is divided into two parts. I. In Part one, a review of published material pertaining to distribution plates, including details from the patent specifications, has been prepared. After a chapter on the determination of the incipient fluidizing velocity, the following aspects of multi-orifice distributor plates in gas fluidized beds have been studied: (i) The effect of the distributor on bubble formation related to the way in which even distribution of bubbles on the top surface of the fluidized bed is obtained, e.g. the desirable pressure drop ratio ?PD/?PB for the even distribution of gas across the bed. Ratios of distributor pressure drop ?PD to bed pressure drop at which stable fluidization occurs show reasonable agreement with industrial practice. There is evidence that larger diameter beds tend to be less stable than smaller diameter beds when these are operated with shallow beds. Experiments show that in the presence of the bed the distributor pressure drop is reduced relative to the pressure drop without the bed, and this pressure drop in the former condition is regarded as the appropriate parameter for the design of the distributor. (ii) Experimental measurements of bubble distribution at the surface has been used to indicate maldistribution within the bed. Maldistribution is more likely at low gas flow rates and with distributors having large fractional free area characteristics (i.e. with distributors having low pressure drops). Bubble sizes obtained from this study, as well as those of others, have been successfully correlated. The correlation produced implies the existence of a bubble at the surface of an orifice and its growth by the addition of excess gas from the fluidized bed. (iii) For a given solid system, the amount of defluidized particles stagnating on the distributor plate is influenced by the orifice spacing, bed diameter and gas flow rate, but independent of the initial bed height and the way the orifices are arranged on the distributor plate. II. In Part two, solids flowback through single and multi-orifice distributors in two-dimensional and cylindrical beds of solids fluidized with air has been investigated. Distributors equipped with long cylindrical nozzles have also been included in the study. An equation for the prediction of free flowback of solids through multi-orifice distributors has been derived. Under fluidized conditions two regimes of flowback have been differentiated, namely Jumping and weeping. Data in the weeping regime have been successfully correlated. The limiting gas velocity through the distributor orifices at which flowback is completely excluded is found to be indepnndent of bed height, but a function of distributor design and physical properties of gas and solid used. A criterion for the prediction of this velocity has been established. The decisive advantage of increasing the distributor thickness or using nozzles to minimize solids flowback in fluidized beds has been observed and the opportunity taken to explore this poorly studied subject area. It has been noted, probably for the first time, that with long nozzles, there exists a critical nozzle length above which uncontrollable downflow of solids occurs. A theoretical model for predicting the critical length of a bundle of nozzles in terms of gas velocity through the nozzles has been set up. Theoretical calculations compared favourably with experiments.

The investigation of vegetation change using remote sensing to detect and monitor migration of landfill gas

Decomposition of domestic wastes in an anaerobic environment results in the production of landfill gas. Public concern about landfill disposal and particularly the production of landfill gas has been heightened over the past decade. This has been due in large to the increased quantities of gas being generated as a result of modern disposal techniques, and also to their increasing effect on modern urban developments. In order to avert diasters, effective means of preventing gas migration are required. This, in turn requires accurate detection and monitoring of gas in the subsurface. Point sampling techniques have many drawbacks, and accurate measurement of gas is difficult. Some of the disadvantages of these techniques could be overcome by assessing the impact of gas on biological systems. This research explores the effects of landfill gas on plants, and hence on the spectral response of vegetation canopies. Examination of the landfill gas/vegetation relationship is covered, both by review of the literature and statistical analysis of field data. The work showed that, although vegetation health was related to landfill gas, it was not possible to define a simple correlation. In the landfill environment, contribution from other variables, such as soil characteristics, frequently confused the relationship. Two sites are investigated in detail, the sites contrasting in terms of the data available, site conditions, and the degree of damage to vegetation. Gas migration at the Panshanger site was dominantly upwards, affecting crops being grown on the landfill cap. The injury was expressed as an overall decline in plant health. Discriminant analysis was used to account for the variations in plant health, and hence the differences in spectral response of the crop canopy, using a combination of soil and gas variables. Damage to both woodland and crops at the Ware site was severe, and could be easily related to the presence of gas. Air photographs, aerial video, and airborne thematic mapper data were used to identify damage to vegetation, and relate this to soil type. The utility of different sensors for this type of application is assessed, and possible improvements that could lead to more widespread use are identified. The situations in which remote sensing data could be combined with ground survey are identified. In addition, a possible methodology for integrating the two approaches is suggested.

Plant oils as fuels for compression ignition engines: a technical review and life-cycle analysis

As an alternative fuel for compression ignition engines, plant oils are in principle renewable and carbon-neutral. However, their use raises technical, economic and environmental issues. A comprehensive and up-to-date technical review of using both edible and non-edible plant oils (either pure or as blends with fossil diesel) in CI engines, based on comparisons with standard diesel fuel, has been carried out. The properties of several plant oils, and the results of engine tests using them, are reviewed based on the literature. Findings regarding engine performance, exhaust emissions and engine durability are collated. The causes of technical problems arising from the use of various oils are discussed, as are the modifications to oil and engine employed to alleviate these problems. The review shows that a number of plant oils can be used satisfactorily in CI engines, without transesterification, by preheating the oil and/or modifying the engine parameters and the maintenance schedule. As regards life-cycle energy and greenhouse gas emission analyses, these reveal considerable advantages of raw plant oils over fossil diesel and biodiesel. Typical results show that the life-cycle output-to-input energy ratio of raw plant oil is around 6 times higher than fossil diesel. Depending on either primary energy or fossil energy requirements, the life-cycle energy ratio of raw plant oil is in the range of 2–6 times higher than corresponding biodiesel. Moreover, raw plant oil has the highest potential of reducing life-cycle GHG emissions as compared to biodiesel and fossil diesel.

The intermediate pyrolysis and catalytic steam reforming of brewers spent grain

Brewers spent grain (BSG) is a widely available feedstock representing approximately 85% of the total by-products generated in the brewing industry. This is currently either disposed of to landfill or used as cattle feed due to its high protein content. BSG has received little or no attention as a potential energy resource, but increasing disposal costs and environmental constraints are now prompting the consideration of this. One possibility for the utilisation of BSG for energy is via intermediate pyrolysis to produce gases, vapours and chars. Intermediate pyrolysis is characterised by indirect heating in the absence of oxygen for short solids residence times of a few minutes, at temperatures of 350-450 °C. In the present work BSG has been characterised by chemical, proximate, ultimate and thermo-gravimetric analysis. Intermediate pyrolysis of BSG at 450 °C was carried out using a twin coaxial screw reactor known as Pyroformer to give yields of char 29%, 51% of bio-oil and 19% of permanent gases. The bio-oil liquid was found to separate in to an aqueous phase and organic phase. The organic phase contained viscous compounds that could age over time leading to solid tars that can present problems in CHP application. The quality of the pyrolysis vapour products before quenching can be upgraded to achieve much improved suitability as a fuel by downstream catalytic reforming. A Bench Scale batch pyrolysis reactor has then been used to pyrolyse small samples of BSG under a range of conditions of heating rate and temperature simulating the Pyroformer. A small catalytic reformer has been added downstream of the reactor in which the pyrolysis vapours can be further cracked and reformed. A commercial reforming nickel catalyst was used at 500, 750 and 850 °C at a space velocity about 10,000 L/h with and without the addition of steam. Results are presented for the properties of BSG, and the products of the pyrolysis process both with and without catalytic post-processing. Results indicate that catalytic reforming produced a significant increase in permanent gases mainly (H2 and CO) with H2 content exceeding 50 vol% at higher reforming temperatures. Bio-oil yield decreased significantly as reforming temperature increased with char remaining the same as pyrolysis condition remained unchanged. The process shows an increase in heating value for the product gas ranging between 10.8-25.2 MJ/m as reforming temperature increased. © 2012 Elsevier B.V. All rights reserved.