1.1.1 The purpose of the E-beam accelerator
The purpose of the accelerator(10Mev/20Kw) is to sterilize the product by using the physical, chemical and biological effects produced by the interaction between the electron beam and the material.
1.1.2 Technical indicators
1.1.2.1 Technical indicators for the whole machine
| Beam energy(MeV) | 9~10 |
| Beam average current(mA) | ≥2 |
| Microwave frequency(MHz) | 2856±0.5 |
| Pulse frequency(Hz) | 5~500 |
| pulse width(ms) | 14~16 |
| Maximum control distance(m) | <20 |
| Scanning width（mm） | 500（500mm under the titanium window） |
| Beam spot size（mm） | F50（500mm under the titanium window） |
| Beam instability（%） | ≤±5 |
| Dose inhomogeneity（%） | ≤±10 |
| Maximum energy consumption per hour（kw.h） | ≤150 |
1.1.2.2 Working conditions
| Ambient temperature | 5oC~30oC |
| Relative humidity | £80% |
| Power supply voltage |
Three phase four wire380V±3%，50Hz。 Voltage stability±3%，Frequency stability±1% |
| Total power | <150kW |
| Radiation protection | According to national standards |
| Ground (two sets) | Grounding resistance<0.4Ω |
Electron linear accelerator's basic working principle is:The electron produced by the electron gun enters the accelerating tube formed by linear acceleration structure under the action of high voltage potential difference of the electron gun. In the process of transmission, when accelerating structure resonance frequency and the klystron of radio frequency (RF) match oscillation frequency, pulse microwave power will be without reflection by accelerating tube input in the front of the coupler.The high frequency electromagnetic field established by microwave makes the electron beam accelerating structure obtain microwave electromagnetic energy continuously so that the electron beam gets bunched and accelerated.
Finally, high energy, high power electron beam is accelerated from accelerator export output into the scanning space, by making use of the magnetic field force of bundles of electronic sweep away with a certain width, from the thin metal film form output window, irradiation was carried out on the items on the conveyor belt, achieve the purpose of disinfection and sterilization, and the products will not have any radioactive residues after irradiation.
Main components include: central control computer；
Accelerator body (including accelerating tube and its accessories: electron gun, traveling wave tubes, waveguide system, vacuum ceramic window, vacuum system, a stainless steel tube for cooling the accelerating tube, focusing magnet, inflating system, scanning magnet, scanning box, support structure, etc.);
Main distribution cabinet;
Power supply cabinet;
Klystron and pulse transformer tank;
Modulator cabinet;
Safety interlock system;
Thermostat unit and cooling unit cabinet;
An interconnection system of water pipes and cables;
Conveyor;
Radiation shielding workshop and other ancillary equipment.
Main technical characteristics：
The modulator uses special charging technology to solve the problem of stable operation under high repetition frequency.
Reasonable installation to reduce beam loss.
The central control computer is composed of several PLC controllers and independently developed control software.Accelerator operation is programmed.
