Queueing at SYD International Arrivals

Apologies if this is addressed in some post #276 in some random existing thread...It's been a few years since I've been through SYD. US passengers can use SmartGate, I am fairly certain... Are there separate queues for Oz citizens and foreign travelers, or do they all go through the same? Does the international arrival process segregate returning citizens and foreign visitors at any point?

Thanks!

(Trying to get details right for a story...)