Can the technology behind particle accelerators be used for space propulsion?

It would be an extremely cumbersome and inefficient way to do it.

Already one uses the acceleration of ions in ion propulsion systems in space:

An ion thruster is a form of electric propulsion used for spacecraft propulsion that creates thrust by accelerating ions. Ion thrusters are categorized by how they accelerate the ions, using either electrostatic or electromagnetic force. Electrostatic ion thrusters use the Coulomb force and accelerate the ions in the direction of the electric field. Electromagnetic ion thrusters use the Lorentz force to accelerate the ions. The term "ion thruster" by itself usually denotes the electrostatic or gridded ion thrusters.[citation needed]

Reply to the edit:

Of course, the LHC cant accelerate 1 kg of protons in an hour, but maybe a derivative of it could and would be the basis of space propulsion system.

Contemplate the LHC system, http://en.wikipedia.org/wiki/LHC . The large circle is 27kimometers diameter. Thousands of magnets and cryogenic support give us a few horsepower in energy. How can this be amplified to the science fiction numbers you propose? Scientists are not crazy to use kilometers of land and enormous power were they able to get the same energy result in miniature.

The technology yes, as the link shows, is usable, but multiplying the energies by enormous factors does not belong to the present technology or available energies. In addition how would one produce megawatts in space? If one can, one does not need an intermediate wasteful step of such magnitude.