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REQUEST FOR PERKIN ELMER XRD0822  FLAT PANEL 
 X-RAY DETECTOR FOR  THE COMPUTED TOMOGRAPHY  
(X-RAY CT) INSTRUMENT IN GEOSCIENCES 
 
 
 
 
 
 
 
 
Proposers  Ian Butler, Stephen Elphick 
Supporters   U0E;-Geosciences Geoffrey Bromiley, Mark Chapman, ,Simon Harley, 
Stuart Haszeldine, Ian Main ,Christopher McDermott, Bryne Ngwenya, Thor 
Thordarson , Rachel Wood, U0E;-CSEC Konstantin Kamenev, U0E;-Engineering  
Chris Hall, Jane Blackford HW;- Gary Couples, Rink van Dijke, Sebastian Geiger, 
Ken Sorbie.  
 
SUMMARY 
We request support to buy a PerkinElmer XRD0822 X-ray detector for the X-
ray Computed Tomography (X-ray CT) instrument recently constructed in-house 
under the ECOSSE program. The new detector will allow imaging and 3D 
reconstruction of large dense samples such as carbonate cores and dense caprocks for 
ICCR and carbon sequestration research, related experimental fluid flow, CO2 and 
deformation studies, and allow imaging of experimental and technical samples 
containing dense inclusions or parts. The detector and related components will cost  
€47,690 including 20% VAT 
 
CONTEXT 
The advantage of having a dedicated X-ray Computed Tomography 
instrument available on-campus has been appreciated for the last decade. Prof. Chris 
Hall submitted a full EPSRC proposal for £345,187 in 2005, which was unfortunately 
not funded. The difficulty has been that because CT is an enabling technology, and 
might form only part of a research proposal, demonstrating an active user need is 
impossible without easy prior access to a suitable instrument, while writing full CT-
based proposals needs initial guaranteed instrument access time. Thus demonstrating 
to a funding council ex novo the need for an expensive full-scale commercial 
installation is almost impossible. 
Availability of ECOSSE funding, and willingness to purchase only core 
components and undertake integration and development in-house, has allowed us to 
sidestep the funding problem. We have constructed an unenclosed X-ray Computed 
Tomography instrument in a part of the experimental laboratories where blast-proof 
walls provide the required radiation shielding, and where there is potential linkage to 
existing experimental capability. Essentially similar to a hospital CT scanner in 
providing reconstructed 3D volume images of samples, the new instrument is  
modular system on a granite optical table, providing maximum flexibility for 
geological and engineering samples. By specifying in-house, purchasing the essential 
components individually, and assembling the instrument and drive software ourselves, 
we have gained access to functionality at a cost of some 30% of the price we know 
companies have paid for similar research capability.  
STATUS: This bid was submitted to the sustainability pot in 2010 and 
received support by the EPS group and the School for funding. It was 
ranked as worthy of support, but being just below the final cut off, it was 
marked to be carried over to the 2011 round. To that end we resubmit the 
bid to the EPS and School with updated costs. 
 TECHNICAL SUBMISSION 
What is a CT instrument 
A functional CT unit consists of five critical elements, three mechanical, and 
two software. The mechanical components are an x-ray source, a rotating table 
holding the sample, and an X-ray camera or planar detector. Added to this mechanical 
unit is the software package which interlinks the rotating table to X-ray image capture 
and download software, and the software packages for 3D reconstruction and 3D 
image manipulation. Medical CT is in essence the same, but the X-ray source and 
camera are rotated, because you are not allowed to spin the patient. 
 
 
 
Figure 1: The ECOSSE CT instrument (left) and a generalised instrument 
configuration for cone beam CT data collection (right) 
 
To obtain a 3D volume image of a sample, the sample is rotated once by the 
table on which it is mounted, while a set of X-ray images are taken at regular angular 
intervals. From this X-ray image set a reconstruction software package can generate a 
digitised 3D model of the object, and this volume image can be sliced or density 
selected as required. The quality of the images generated is determined by the spot 
size of the X-ray source, and the sensor or pixel spacing in the X-ray camera. The 
amount of magnification is determined by how close the sample is placed to the 
source relative to the distance between source and camera. For example, a small 
sample can be heavily magnified by placing it close to the X-ray source, so that it 
casts a large X-ray shadow onto the camera. 
 
How does our current capability compare 
 
Our in-house CT instrument is equal in capability to any but the most 
specialist NanoCT instruments, and equals or betters current commercial instruments. 
The component list is very similar to that specified by the University of Ghent when 
setting up their CT laboratory, because the individual components are the best that 
either group could source.  Figures 2-5 - appended illustrate that on small samples 
such as individual oceanic forams we can achieve a voxel resolution of one micron. 
(A voxel is the volumetric equivalent of a pixel in 2D) This means that we can map 
the internal volume and geometry of a 1mm foram at 1 micron resolution. We can 
achieve this resolution because the X-ray source can achieve sub-micron spot sizes, 
and the X-ray camera has a pixel pitch of 50 microns, one of the finest available. 
By varying the position of the sample between X-ray source and camera, we 
can image suitable samples between 1mm size at one micron resolution up to 50mm 
samples at 50 micron resolution. The capability of our current instrument is shown in 
Figs 2-5 appended. 
 
Technical justification for new camera 
 
The Problem 
When specifying the initial CT mechanical component set, of X-ray source, 
revolving sample table, and X-ray camera, we had to purchase a matched set suitable 
for as wide a range of potential ECOSSE and School samples as possible, within the 
constraints of available funding.  
After rigorous specification, we purchased a CMOS camera with 10cm by 
10cm active area. This camera has:  1) a 50 micron pixel spacing, giving access to 
high resolution (4 megapixel) capability for small samples, 2) is a good match to the 
available energy range from the X-ray source, and 3), a reasonable (12-bit) range in 
its exposure capability. The latter is important because it is capture of subtle ranges of 
density variation which enable detailed 3D reconstructions. It is notable that 
University of Ghent began their CT unit with a similar camera from the same 
manufacturer, presumably for the same reasons. 
Although this camera gives superb images and reconstructions, as instanced 
by the images appended to this request, it necessarily also has some compromise 
features. These are; the limited size of the camera capture area, the sensitivity range 
available per image, and the susceptibility to radiation damage. 
The 10cm by 10cm active area of the current camera means that this is the 
largest sample which can currently be imaged. The situation is slightly worse, 
however, because the width of the sample table makes it mechanically impossible to 
place the sample immediately adjacent to the camera. There is thus always some 
geometric magnification during imaging, meaning that the largest sensibly achievable 
sample size is currently 5 cm width by 7cm tall. 
The 12-bit image greyscale depth of the present camera is very reasonable, but 
for certain types of sample, such as larger carbonate or caprock core samples, so much 
energy is absorbed by the sample that the image which can be captured is lacking in 
exposure detail. In other words, all the image detail needed to enable a 3D 
reconstruction is contained within a band of 3 or 4 bit depths within the 12-bit 
greyscale nominally available from the camera. The only way around this problem is 
to take multiple images at each individual position, and rescale these to a single image 
frame with better resolution. However, a detailed reconstruction of an average sample 
usually requires a 10 second exposure step at 800 different positions, taking 1hour 20 
minutes for data capture alone. Multiplying this by five to achieve adequate image 
tonality becomes very burdensome. Our CT is not unusual in this, detailed core 
scanning to the resolution we can reach is routinely reported as taking 24 hours. 
Lastly, there is the problem of radiation damage, which is linked to the first 
two aspects above. The X-ray camera consists of a scintillator deposited over an opto-
electrical sensor array. When an X-ray hits the scintillator, it generates a flash of light 
which is captured by the underlying electronics. While this digital geometry is 
powerful, and has replaced X-ray film in medical imaging work, it necessitates the 
electronics being placed directly in the X-ray beam. This results in gradual 
degradation of the imaging capacity of the camera, ie it is slowly fried by the X-ray 
beam, and gives a gradually poorer and grainier image. Unfortunately, CMOS 
cameras are particularly susceptible to this radiation damage, which limits their use to 
specialist imaging applications. 
The three individual weaknesses of the current CMOS camera are self-
reinforcing for an important subset of samples of great geological interest for oil and 
sequestration studies. Worst case is detailed imaging of 38mm dense carbonate core. 
In this application, the sample is so attenuating that both the X-ray energy and power 
have to be maximised to obtain a reasonable image in a sensible time. However, X-
rays hitting the camera around the edges of the sample, where there is no heavy 
attenuation, are blasting directly at full power into the camera electronics. This, and 
the required prolonged exposure times to achieve decent images, causes excessive 
cumulative radiation damage down the edges of the current CMOS camera.  
 
The solution 
The practical solution adopted by research CT facilities is to use different 
cameras dependent on the sample type involved. We propose purchasing a Perkin 
Elmer XRD0822 for use with dense and large samples. This camera has an image area 
20cm by 20cm, four times that of the present camera, allowing us to image much 
larger samples. The proposed camera can capture 100 frames per second, against the 
2.7 frames per second of the current CMOS camera. This makes it is better suited to 
the capture of transient phenomena such as labelled fluid flow in samples. And most 
importantly, the Perkin Elmer camera uses an amorphous silicon detector type which 
is much less sensitive to radiation damage than our CMOS camera, and is available in 
a range of scintillator types that can be matched to the high energy range of our 
system. These cameras are used in routine Non-destructive Testing (NDT) 
environments, under continual X-ray irradiation, and are very heavily shielded.  
 
The proposed camera would add critically to our capability in an 
important area of imaging and CT work. 
 
COSTINGS 
 
Detector Type Short description Price in EURO   
XRD 0822 CP3 IND  25-100 fps, Rad Hard Panel € 36,800.00  
0822 - Accessories   
Power Supply XRD-EPS 215W 95510354H 
€ 1,160.00  
XRD EPS B2 DC Cable 7.6m   95510586H 
€ 180.00  
XRD EP Power Supply AC Cable EP – 
DE 95510331H € 32.00  
XRD GigE Interface Cable 50Ft / 
15.25M 95510622H € 209.00  
Shielding Cassette 160kV (Optional) 95510051H € 1,360.00  
Prices are Ex-Works Wiesbaden 
(Germany) TOTAL EX VAT €39,741.00 
 TOTAL INC VAT@20% €47,690.00 
 
BUSINESS AND SCIENCE PLAN 
 
Current Profile 
 
Component specification, sourcing, purchase and integration has taken two 
years, with the X-ray source commissioned Aug 2009.  The first  tomographic 3D 
reconstruction  was obtained in Jan 2010.  Because we have been learning as we go, 
including optimising drive and data software, and learning the essential parameters for 
obtaining research-grade 3D images, we have not advertised the CT capability, but 
allowed the science project base to grow organically through the ECOSSE 
collaborative mechanism. In some projects CT gives added value, in others, it is a 
critical component of the research proposal. All access except proof of concept for 
grant proposals is at FEC rating. 
 
Projects in progress or funding secured 
 
“IMVUL – towards improved aquifer vulnerability assessment” EU Framework 7 
Marie Curie ITN. 48 Months. Dr S. Elphick, Dr B Ngwenya and Dr I Butler. €405K  
(€3.2M total network budget).     CT imaging of biofilm growth 
 
“CO2SolStock - Biobased Geological CO2 Storage”. EU Framework 7 Future 
Emerging Technologies Round. 36 Months. Dr B. Ngwenya Dr I. Butler, Dr S. 
Elphick, Dr R. Wood, Prof S. Haszeldine. €2.98M Coordinated by Edinburgh. €817K 
to Edinburgh.  CT imaging of biological precipitates in sand and soils 
 
“MUSTANG - A Multiple Space and Time Scale Approach for the quantification of 
deep saline formations for CO2 storage” 24 Months. Dr C. McDermott, Prof. S 
Haszeldine and Dr I Butler. €9.8M Total project, €610K to Edinburgh. CT 
imaging of CO2-water-rock reaction zone in cap rocks (essential project 
component) 
 
“Validation and verification of discrete fracture flow models for fractured carbonate 
rocks” EPSRC/Exxon-Mobil Case Studentship. 36 months. Dr S. Geiger (HW), Dr I. 
Butler, Dr S. Elphick £87K (ECOSSE Project held at HWU). CT imaging of 
fluid flow in fractured carbonates (essential CT component) 
 
“Localizing signatures of catastrophic failure (LOCAT)” EPSRC/ERC Project Grant, 
and part of European Complexity Network. 24 Months. Prof. I. Main, Dr I Butler, 
Prof M. Zaiser (Engin.). £127K CT Characterisation of fractured materials 
 
“Satutrack - Saturation tracking and identification of residual oil distributions using 
X-Ray CT, SEM, and pore-scale modelling techniques.” Petrobras industry funded 
project supported through ICCR. 36 Months.  Dr I. Butler, Dr S. Elphick (UoE), Dr S. 
Geiger, Dr R. van Dijk, Prof K. Sorbie (HWU). £183K CT measurements of 
oil/brine distributions in porous carbonates (essential CT component) 
 
“In-situ X-ray tomographic imaging under extreme conditions: a proof of concept 
study”. NERC Small Project Grant. 18 months. Dr G. Bromiley, Dr I Butler. £57K CT 
method development for on-line HPHT experimentation. 
 
Current User Base 
UoE Geoscience Users through project association: I. Butler, G. Bromiley, S. 
Elphick, S. Haszeldine, I. Main, C. McDermott, B. Ngwenya,, R. Wood,. 
 
Other UoE users (through project association or applications) 
Prof. M. Zaiser, Dr Jane Blackford. 
 
Project Students, PhDs, Postdocs and Resarch Techs: 
Ms M. Berg (PhD), Ms. H. Kurlanda (Marie Curie PhD), Ms C. Fricke (EPSRC PhD 
HWU), Dr K. Edlmann (EU PDRA), Mr K. Dodds (EU Research Tech) Mrs Tannaz 
Pak (ICCR PhD). 
 
ECOSSE Users (Through Project association) 
Dr S. Geiger, Dr R. van Dijk, Prof. K. Sorbie. (all HWU) 
 
Wider Interest from other institutions and industry: 
Dr Richard Harrison and Dr Nathan Church (Cambridge Earth Sciences); Dr Stig 
Walsh (National Museum of Scotland). Collaboration with Exxon-Mobil and 
Petrobras (through links to HWU and through ICCR). 
 
Future Profile 
 
Now that there are established users, and confidence in the stability of the 
component and software interoperability, it is feasible to start longer-term planning 
for the CT instrument.  
The first step is to upgrade the camera, to optimise imaging capability, which 
the current application addresses. The current manual component positioning system 
is being upgraded to precision motor-driven placement, making the instrument much 
more user-friendly. The instrument and its capability will be more widely advertised 
through the School and via the ECOSSE mechanism, enabling researchers to plan CT-
based projects which will have competitive novelty compared with other institutions.  
As usage builds up, and can no longer be serviced by existing in-house staff, 
the full FEC costings we use will allow training of an operator/software engineer, first 
on a part-time basis, and then full-time. The dedicated in-house expertise can then be 
leveraged across the Science faculty to help develop novel CT applications and 
techniques, a model which has proven successful at the University of Ghent, where a 
small CT capability has been built into a thriving science and software unit. Our aims 
are more modest, to provide a center of excellence for CT related imaging and 
experimental work in Scotland, with the potential for additional growth if it proves 
merited. 
 
 
 
 
 
 
 
Figure 1: X-ray CT image of a fractured carbonate core (lower image) with the 
fracture volume extracted and rendered separately (upper image). 
 
 
 
 
Figure 2: X-ray CT image of a woodcock skull. Data acquired in collaboration with 
Dr Stig Walsh, National Museum of Scotland. 
 
 
 
 
 
 
 
Figure 3: X-ray CT reconstruction of an olivine-Fe/FeS pellet from high pressure and 
temperature piston cylinder experiment. In images a-d 3D rendering software has 
been used to increase the transparency of the olivine matrix (green) to reveal the 
distribution of Fe/FeS inclusions within the sample. Sample diameter = 2mm, scan 
resolution = 3 microns. 
 
 
 
 
 
 
  
 
Figure 4: X-ray CT reconstruction of a single foraminifera showing details of internal 
structure of the carbonate shell (Sample diameter = 1mm, scan resolution = 1 
microns).