An A320 Captain reported losing #2 engine bleed after departing with #1 engine bleed deferred. They declared an emergency and returned to departure airport. Captain reported that for some reason ATC was vectoring them for sequence even though they were an emergency aircraft.

Narrative

[We had a] normal preflight and boarding. Previous gripe; engine 1 high pressure (HP) bleed valve fault was fixed overnight so no MEL items on release. On taxi out we got an ECAM for the engine 1 HP bleed valve fault. Stayed on ramp; contacted Maintenance but could not clear it. As I had added fuel and the weather was VFR; we agreed to a deferral and did not have to return to the gate. Upon receiving the new release and complying with its restrictions we got a new flight plan for FL300 with the MEL applied. Climbing through 14;000 FT we got engine 2 bleed fault ECAM. Two resets were unsuccessful and as engine 1 bleed was closed per the deferral; I declared an emergency to return to departure airport. Using emergency authority I opened engine 1 bleed as the low pressure valve was working fine; this controlled the cabin pressure. My First Officer was the pilot flying and he handled ATC and flew the aircraft while I told the flight attendants we would be back on the ground in 7 minutes. Message was sent to Dispatch via ACARS followed by a PA to the passengers. All ECAMS were done and no overweight checklist to contend with. Started the APU and resumed ATC communications. Oddly enough; ATC was vectoring us for sequence. Confirmed we were an emergency aircraft and requested vectors for landing airport in sight. They seemed perturbed by this; not sure why; but oh well. On clearing the runway I advised Tower that we would taxi to the gate and no further assistance was needed from the emergency vehicles. Taxi to the gate and parking was uneventful. Upon shutdown and checklists complete; made a PA to passengers with more info as to why the return.