I have to thank all of you guys.
You helped me a lot.
Mr. Bulia Byak, Jamie Kimberley, John Bintz and others.
You are all right. The Inkscape is a great software but not for what I was
trying to do. The ideas that Kimberley and Bintz gave to me was perfect. 
ImageMagick was the right answer to my problem. I did this:
- I exported the entire SVG to a single PNG file. That gave me a file with a
  bit more than 19MB.
- I converted the PNG in a MPC file with ImageMagick, after a long and very
  careful reading of its documentation. This gave me a file almost 4GB long.
- Then I made a batch script, much more simpler than the other one, to export
  all the 29,232 parts that I needed.
Amaizing, it took less than 4 hours to export all parts. I loved ImageMagick
and all its powerful. I already known it, but never occurs to me that it could
do the job.
Thank you again, guys.
Alessandro Antonello