It is possible and quite easy. You can find WG.EXE in your Visual Studio folder. WG.EXE is actually the command line minifier that calls the same minification libraries. You can use it from command line, or from MSBuild or from any script of your choice to do the minification.
Here is a good article written by WG team on how to use WG from command line: https://kenhaines.net/webgrease-as-seen-in-visual-studio-2012/
you may also check https://webgrease.codeplex.com/documentation
for detail information