Trade

1. CABINET X-RAY MACHINE AND SMALL-
SCALE IRRADIATION
Peter Follett, Research Entomologist
USDA-ARS
U.S. Pacific Basin Agricultural Research Center
Hilo, Hawaii

2. Overview
• Who wants small scale irradiators?
•In-line cabinet X-ray irradiator
• Radsource’s 4-Pi X-ray tube
• Comet’s X-ray emitter
• Potential for E-beam

3. Hawaii pride X-ray irradiator

4. Phytosanitary irradiation
What is the feasibility of in-line irradiation?
Airport baggage screening

5. Cabinet X-ray irradiators
Why growers might be interested…
• Costs a fraction of a
stand alone facility (<$1
million)
• Treat fruit the same day
it’s packed – no
transportation
• Moveable - ready-made
for domestic quarantines
• Under grower’s control
• Methyl bromide alter.
• Can treat fruit cold
• Simple solution
Potential application:
• Sweet cherries to
Australia and Mexico
(spotted wing drosophila)

6. Requirements
• Good penetration
Different box types
• Good dose uniformity
ratio
At 400 Gy, <1 kGy
maximum
• Sufficient throughput
• Gentle on commodity
• Low cost
• Portable, self-shielded
• Reliable during
continuous use
• Two candidates:
X-ray emitter
4-P1 X-ray tube

7. In-line cabinet X-ray irradiator
XBA-180 X-ray emitter
Concept
design:
Dominique
Cloetta
Comet AG
XBA-180 X-ray emitter

8. Comparison to conventional X-ray tube
 Geometry not optimal
 Small angle of radiation
 Low dose rate – 1/r2
 Large surface emitter
 Broad radiation beam
 Higher dose rate >1/r

9. Simulation for papaya box
Dr. Dominique Cloetta (Comet)Gy
m
At 180kV, 4.5kW and 10cm/min conveyor speed:
Min. dose: 78Gy, max. dose: 109Gy
DUR: 1.4
 at 5cm/min: Min. dose: 156Gy, max. dose: 218Gy
 at 1.95cm/min: Min. dose: 400Gy, max. dose: 559Gy
 at 1.09cm/min: Min. dose: 716Gy, max. dose: 1000Gy

10. X-ray emitter
Papaya test
Comet AG
Flamatt,
Switzerland
DUR
Flat = 1.9
Upright = 1.2
X- ray emitter

11. In-line cabinet x-ray irradiator
4-Pi x-ray tube
Concept
design:
Randy Kirk
Applied
Energy
Devices
4-pi X-ray tube

12. 12
Transportable Container

13. Upender
Shipping
Container
Pneumatic
Actuator
Pneumatic
Actuators
Portable X-ray Irradiator
VENT
Lead
26”
60”
Power Supplies
ECS
Cooler Cooler Cooler
7’
= x-ray tube
13’

14. New x-ray tube design
• Dan Gorzen
• X-ray and
Specialty
Instruments Inc.
• 160 kV, 20 mA
• 35 cm radiation
field
• 10% variation

15. Cabinet x-ray machine
Under construction
 Inside portable
container
 Self shielded (lead)
 Computer interface
 Irradiates box from
bottom then top
 Throughput varies
by dose

16. Potential for electron beam
Ex: Prima Frutta, Linden, CA
• High volume
• 15,000 boxes per day
• 1 box per 4 sec
• Short harvest
• 2 months
• Continuous use
• Treat in cold room
Sweet cherry packing house Single layer of fruit

17. Potential for E-beam
Ex: Prima Frutta, Linden, CA
• High volume
• 15,000 boxes per day
• 1 box per 4 sec
• Short harvest
• 2 months
• Continuous use
• Treat in cold room
Sweet cherry requirements In-line e-beam

18. Size versus performance
• Boxes
• DUR
1.5
• Throughput
100s lbs/hr
• Cost
$1 million
• Carrier
• DUR
1.5-2.0
• Throughput
1000s lbs/hr
• Cost
$3-10 million
Small Medium Large
• Pallet
• DUR
2.5- 3.0
• Throughput
10,000s lbs/h
• Cost
$10-30 million