1,336 research outputs found
A review of the AMM & CMM resources in the Kuznetsk (Kuzbass) Coal Basin, Russia
This report describes some of the results of a visit to Russia between 7-17th June 2005 to study the Coal Mine Methane and Abandoned Mine Methane resources of the Kuznetsk (Kuzbass) Coal basin, Siberia, Russia. Coal Mine Methane (CMM) refers to gas drained from working coal mines and Abandoned Mine Methane (AMM) refers to mine gas derived from closed mines. This visit formed part of the UK – Russia Cleaner Fossil Fuel Technology Transfer Project: AMM/CMM Technology Transfer Opportunities in Russia. The UK team comprised experts from Wardell Armstrong, British Geological Survey (BGS), IT Power and Climate Mitigation Works; Uglemetan provided support whilst in Russia. The role of the BGS was to evaluate the CMM and AMM resources of the Kuzbass Coal Basin and, if possible, to apply the UK scheme for resources and reserves assessment on the basis of such data as was available in Russia. However, due to significant problems in obtaining suitable data whilst in Russia, a Kuzbass-wide assessment of AMM and CMM resources was not possible. Hence this report represents a review of existing published and non-published data and meetings held during the visit to Russia in 2005, where they impact on AMM and CMM resources. This report is not a definitive assessment of the CMM and AMM resources and reserves of the Kuzbass and the conclusions reached are tentative. Hence it is recommended that more detailed studies be carried out in order gain a better understanding of the CMM and AMM resources and reserves in the Kuzbass.
The Kuzbass Coal Basin covers an area of approximately 26,000 km and is thought to contain 263.7 billion tonnes of coal reserves. The main coal-bearing intervals are from the Permo-Carboniferous Kolchuginsky and Balakhonsky stages and, typically, the coal to overburden (non-coal) ratio is about 3.5:1. The area is geologically complex, with large folds and thrust folds dominating. The working underground mines generally operate around the western periphery of the basin, mostly exploiting coals with ranks varying from High Volatile C Bituminous to Low Volatile Bituminous. More than 100 seams, with an average thickness of 2.5 m, have been mined at depths varying from 300-800 m. Ash and moisture contents average about 20 % and 7 % respectively and the gas content averages 12 m3/t.
Coalbed methane resources of the Kuzbass coal basin are thought to be over 13 trillion cubic metres but so far there has been limited exploration for and exploitation of methane. There are presently about 36 working underground mines and there are considerable CMM resources. Annual methane emissions into the atmosphere from Kuzbass coal mines amount to 1-2 billion cubic metres, equal to the annual natural gas consumption in the region. In 1994, out of a total emission of approximately one billion cubic metres of methane, ventilation systems emitted 860 million cubic metres and methane recovery systems emitted 196 million cubic metres following collection. Four examples of potential CMM schemes are described within the report, from Abashevskaya, Chertinskaya, Komsomolets and Pervomaiskay mines. There appears to be a link between high coal productivity and increased methane emissions. In 2005 there are only 13 mines that use degasification systems. Most mines use air from the ventilation system to dilute the methane to safe (non-explosive) concentrations. Hence, for the majority of working mines, capturing the ventilation air methane (VAM) would be the most sensible approach to utilising the CMM.
There are 43 abandoned coal mines in the Kuzbass, many of which have potential for AMM utilisation. On closure it has been estimated that a typical Kuzbass mine emits 107 m3 of methane. The mine closure agency Gorsh is responsible for monitoring mines after closure. Of the 43 closed mines 13 are fully flooded, 15 are partially flooded, and 15 are maintained dry through pumping out of water. There are a further 17 mines that have no documentation or monitoring. Following mine closure and the cessation of pumping, groundwater levels rise quickly, with mines typically flooding within 3-7 years. Hence an understanding of minewater rebound is critical to any successful AMM scheme in the Kuzbass. Data provided by Gorsh show that 86% of the mines have 65% or more of their total volume flooded. Therefore the number of possible AMM schemes is severely limited as a result of minewater recovery and there are perhaps 5-7 suitable prospects
Cumbria and the northern Pennines
Carboniferous rocks within the Cumbria and northern Pennines region are bound by
the Maryport–Stublick–Ninety Fathom Fault System, which forms the northern
boundary of the Lake District and Alston blocks (Fig. 12.1). In the Pennines, the
succession occupies the Alston and Askrigg blocks and the intervening Stainmore
Trough, a broadly east-west trending graben. Carboniferous strata also flank the Lake
District High, occurring at outcrop in north Cumbria, Furness and Cartmel (south
Cumbria) and the Vale of Eden, and in the subsurface in west Cumbria. The Askrigg
Block succession is separated from that of the Craven Basin (Chapter 11), to the
south, by the Craven Fault System
Craven Basin and southern Pennines
Carboniferous rocks within this area occupy the region contiguous with the northern
Pennines to the north (Chapter 12) and the Peak District to the south (Chapter 10). All
of the stages of the Carboniferous are present at outcrop, with the exception of
Stephanian strata, which are absent. The oldest Tournaisian strata crop out within the
Craven Basin, and are represented by ramp carbonate rocks (Bowland High Group)
deposited on the Bowland High and adjacent Lancaster Fells and Bowland sub-basins.
These carbonate rocks are overlain by mainly Visean hemipelagic mudstone and
carbonate turbidites (lower part of Craven Group). To the south of the Pendle Fault
System (Fig. 11.1), further platform carbonate rocks are proved in the subsurface
above the Central Lancashire High (Trawden Limestone Group) and the Holme High
and Heywood High (Holme High Limestone Group). These carbonate rocks, which
developed during the Tournaisian to late Visean, are known only from well records
and geophysical information and are not divided into formations. During the Visean,
the platform carbonate rocks pass laterally into more basinal successions in the
Harrogate, Rossendale and Huddersfield sub-basins (Craven Group). The
lithostratigraphical nomenclature for the Tournaisian and Visean strata is that of
Waters et al. (2009), adapted from Riley (1990)
A guide to the construction of the DGSM Nottingham Melton Lithoframe 50K Colston Bassett Gocad model
This report describes the rationale behind the construction of the Nottingham Melton Lithoframe 50K GOCAD model for the Colston Bassett area. This work was carried out between April 2001-March 2005, as part of the Nottingham Melton DGSM-UK project (E1362S96 Task 06). This model comprises part of the area covered by the Melton 50K geological map sheet (142)
South Wales
Carboniferous rocks in this region occur in a broadly east-west trending syncline, the
core of which includes the South Wales and Pembrokeshire coalfields (Fig. 5.1).
Tournaisian and Visean strata (Avon and Pembroke Limestone groups) represent
deposition on a southward prograding carbonate ramp evolving into a carbonate shelf
(Wright 1987), in a succession which shows similarities to that of the Bristol and
Mendips areas (Chapter 6). The main outcrops, in south Pembrokeshire, Gower and
the Vale of Glamorgan, occur along the southern periphery of the coalfields and are
commonly affected by Variscan thrusting and folding. Thinner successions occur
along what is termed the East Crop and North Crop of the South Wales Coalfield,
where much of the Visean succession is absent due to sub-Namurian and intra-Visean
unconformities. Namurian fluvio-deltaic deposits (Marros Group) flank the South
Wales and Pembrokeshire coalfields. Much of the lower and middle Namurian
succession is absent across the region, except in the west of the South Wales Coalfield
where only small parts are absent beneath an intra-Namurian unconformity.
Westphalian fluvio-lacustrine deposits (South Wales Coal Measures Group) form the
South Wales and Pembrokeshire coalfields, located to the east and west of
Carmarthen Bay, respectively. Westphalian to Stephanian Pennant alluvial facies
(Warwickshire Group) occur in the core of the South Wales Coalfield syncline.
Deposition of the South Wales Coal Measures and Warwickshire groups was
probably laterally contiguous with those in the Bristol and Somerset coalfields
(Chapter 6), but the Usk-Cowbridge High controlled and restricted sedimentation for
much of the Carboniferous, with pre-Namurian uplift and erosion removing the
Tournaisian and Visean succession. Later uplift is also believed to have caused
attenuation of the Warwickshire Group in the east of the South Wales Coalfield. The
lithostratigraphical nomenclature for the region is that of Waters et al. (2007; 2009)
Lithostratigraphical subdivision of the Sherwood Sandstone Group (Triassic) of the north-eastern part of the Carlisle Basin, Cumbria, and adjacent parts of Dumfries and Galloway, UK.
This report presents a review of the history of the lithostratigraphical subdivision of the Triassic
Sherwood Sandstone Group of the north-eastern part of the Carlisle Basin, Cumbria, and
adjacent parts of Dumfries and Galloway, UK. Two formations, the St Bees Sandstone and
Kirklinton Sandstone, have been mapped in the past. However, previous workers have found
considerable difficulty in consistently identifying, defining and mapping the Kirklinton
Sandstone Formation. Moreover, previous accounts of the sandstones in the Carlisle area appear
to suggest that the succession there differs in several key aspects from its correlatives in other
parts of Cumbria and, in particular, the adjacent offshore area. As a result of a short period of
field work in the area, it is concluded that the principal lithological change is between mainly
fine-grained sandstones, that are generally or commonly micaceous and contain common or
numerous mudstone interbeds, in the lower and middle parts of the group, and fine- to coarsegrained
sandstones with rare or no mica and mudstone partings at the top of the group. This
change occurs within the Kirklinton Sandstone Formation as previously mapped, and it is
suggested that this unit is now invalid. Several options are considered as to how the group should
be subdivided and the nomenclature to be adopted. All options presently have some associated
problems, but the adoption of the same terminology as in the continuous offshore is suggested,
i.e. St Bees Sandstone Formation below (subdivided where possible into Rottington Sandstone
and Calder Sandstone Members) and Ormskirk Sandstone Formation above
A guide to the construction of the DGSM Nottingham Melton Lithoframe 250K model
This report describes the rationale behind the construction of the Nottingham Melton Lithoframe 250K GOCAD model. This work was carried out between April 2001-March 2005, as part of the Nottingham Melton DGSM-UK project (E1362S96 Task 06). This model comprises the area of the combined Nottingham and Melton 50K geological map sheets
The Scremerston Formation : results of a sedimentological study of onshore outcrop sections and offshore Well 42/13-2
This report describes a study of the Scremerston Formation and lower part of the overlying
Yoredale Formation at outcrop and in the onshore subsurface in the Berwick-upon-Tweed area
of north-east Northumberland. The work was carried out on behalf of Sterling Resources Ltd and
partners, who were interested in the onshore succession as an analogue to similar aged deposits
offshore in their area of interest in the North Sea (Quadrant 42 and adjacent areas).
The work was carried out in two phases. Firstly a field-based study of coastal and inland
outcrops in the Berwick area was carried out during February 2007. The Scremerston Formation
is poorly exposed onshore at Berwick, although the overlying succession, equivalent to the basal
part of the offshore Yoredale Formation, is well exposed to the north and south of Berwick.
Sedimentologically the Scremerston Formation and lower part of the overlying Yoredale
Formation appear similar. The main difference appears to be the occurrence of thick marine
limestones in the Yoredale Formation. Hence it is believed that it is valid to include the lower
part of the Yoredale Formation within the study.
Overall the succession represents deposition on a delta plain, transitional with a marine setting.
Periods of delta advance led to the infilling of marine interdistributary bays. Floodplain and
lacustrine facies occur on the delta plain, as well as large braided river channel systems that fed
coarse sediment into the basin. The study found that a variety of reservoir and non-reservoir
lithofacies characterise the succession. The largest sandbodies consist of stacked major channel
systems, up to about 88 ft (27 m) in thickness. These have widths that vary up to about 8 km.
Palaeocurrent analysis of the sandbodies show that they have a consistent trend, with sandbodies
oriented north-south or north-east to south-west; a southerly or south-westerly flow direction is
indicated. The channel fills typically consist of fine- to coarse-grained cross-bedded sandstone,
with a high net-to-gross (typically >0.8). Internal heterogeneity, where present, typically
comprises beds of floodplain mudstones. These are often discontinuous due to erosion by
overlying channels.
The second part of the study involved an analysis of boreholes in the area around and
immediately to the south of Berwick. In total 39 onshore boreholes were databased, irregularly
distributed across an area of approximately 100 km2 (~39 square miles). Borehole stick plots
were drawn, stratigraphic correlations made and sand-to-non-sand maps were constructed. These
sand-to-non-sand maps represent a crude proxy for net-to-gross sand maps and show that, at least
onshore, the succession shows significant lateral variability in sand distribution. Schematic
palaeogeography maps were compiled for 6 sandbodies within the Scremerston and Yoredale
formations. This utilised the borehole and outcrop data
Observation of Neutrons with a Gadolinium Doped Water Cerenkov Detector
Spontaneous and induced fission in Special Nuclear Material (SNM) such as
235U and 239Pu results in the emission of neutrons and high energy gamma-rays.
The multiplicities of and time correlations between these particles are both
powerful indicators of the presence of fissile material. Detectors sensitive to
these signatures are consequently useful for nuclear material monitoring,
search, and characterization. In this article, we demonstrate sensitivity to
both high energy gamma-rays and neutrons with a water Cerenkov based detector.
Electrons in the detector medium, scattered by gamma-ray interactions, are
detected by their Cerenkov light emission. Sensitivity to neutrons is enhanced
by the addition of a gadolinium compound to the water in low concentrations.
Cerenkov light is similarly produced by an 8 MeV gamma-ray cascade following
neutron capture on the gadolinium. The large solid angle coverage and high
intrinsic efficiency of this detection approach can provide robust and low cost
neutron and gamma-ray detection with a single device.Comment: 7 pages, 4 figures. Submitted to Nuclear Instruments and Methods,
Nutrient transport in bioreactors for bone tissue growth : why do hollow fiber membrane bioreactors work
One of the main aims of bone tissue engineering is to produce three-dimensional soft bone tissue constructs of acceptable clinical size and shape in bioreactors. The tissue constructs have been proposed as possible replacements for diseased or dysfunctional bones in the human body through surgical transplantations. However, because of certain restrictions to the design and operation of the bioreactors, the size of the tissue constructs attained are currently below clinical standards. We believe that understanding the fluid flow and nutrient transport behaviour in the bioreactors is critical in achieving clinically viable constructs. Nevertheless, characterization of transport behaviour in these bioreactors is not trivial. As they are very small in size and operate under stringent conditions, in-situ measurements of nutrients are almost impossible. This issue has been somewhat resolved using computational modelling in previous studies. However, there is still a lack of certainty on the suitability of bioreactors. To address this issue we systematically compare the suitability of three bioreactors for growing bone tissues using mathematical modelling tools. We show how nutrient transport may be improved in these bioreactors by varying the operating conditions and suggest which bioreactor may be best suited for operating at high cell densities in order to achieve soft bone tissues of clinical size. The governing equations defined in our mathematical frameworks are solved through finite element method. The results show that the hollow fiber membrane bioreactor (HFMB) is able to maintain higher nutrient concentration during operation at high cell densities compared to the other two bioreactors, namely suspended tube and confined profusion type bioreactor. Our results show that by varying the operating conditions nutrient transport may be enhanced and the nutrient gradient can be substantially reduced. These are consistent with previous claims suggesting that the HFMB is suited for bone tissue growth at high cell densities
- …