  We consider model A dynamics for a heating quench from the disordered
(confined) into the ordered (deconfined) phase of SU(3) lattice gauge theory.
For $4 N_{\sigma}^3$ lattices the exponential growth factors of low-lying
structure function modes are calculated. The linear theory of spinodal
decompositions is compared with the data from an effective model and the Debye
screening mass is estimated from the critical mode. Further, the quench leads
to competing vacuum domains, which make the equilibration of the QCD vacuum
after the heating non-trivial. We investigate the influence of such domains on
the gluonic energy density.
