EA30 CREW WAS UNABLE TO PRESSURIZE ACFT AFTER TKOF.

Narrative

AFTER TKOF FROM MIA; ACFT PRESSURIZATION WAS ABNORMAL AS A RESULT OF THE AFT OUTFLOW VALVE BEING STUCK IN THE FULLY OPEN POS. WE LEVELED WITH DEP CTL'S PERMISSION AT 10000 FT. DID SOME TROUBLESHOOTING AND THEN SPOKE TO MIA MAINT FOR SUGGESTIONS. WE WERE REQUESTED TO RETURN TO MIA. FLT ATTENDANTS WERE ADVISED AND A PA WAS MADE IN PREPARATION FOR THE RETURN. WE REQUESTED A RETURN; WERE GIVEN RWY 27R; BUT REQUESTED THE LONGER RWY 27L AND ASKED FOR CFR VEHICLES TO BE STANDING BY. RAN THE CHKLISTS; CHKED THE CHARTS FOR ANY RWY OR GAR LIMITS; AND PROCEEDED WITH THE APCH TO RWY 27L. ALL WENT WELL WITH THE APCH RESULTING IN A NORMAL LNDG IN THE TOUCHDOWN ZONE AT A VERT SPD OF APPROX 200 FPM. SUPPLEMENTAL INFO FROM ACN 447775: AFTER TKOF FROM MIA; RECEIVED ADVISORY FROM ECAM INDICATING AFT OUTFLOW VALVE FULL OPEN. UNABLE TO CTL CABIN; LEVELED OFF AT 10000 FT. ADVISED ATC; RAN LOSS OF CABIN PROC. COULD NOT CTL IN AUTO OR MANUAL. CONTACTED MIA MAINT. THEY SUGGESTED CHK CIRCUIT BREAKERS. THEY WERE OK; THEN SUGGESTED RETURN TO MIA AND LAND. ADVISED ATC; REVIEWED OVERWT LNDG. REQUESTED CFR. ADVISED FLT ATTENDANTS; RAN ALL CHKLISTS AND LANDED. NORMAL TOUCHDOWN. MIA MAINT INSPECTED AND FOUND AFT OUTFLOW VALVE SCREEN DAMAGED. PROBABLY FROM SECURITY/CUSTOMS INSPECTION.