California has had near zero flare requirements for over a decade here is on article on how this can be accomplised:

http://www.baaqmd.gov/~/media/files/compliance-and-enforcement/flares/2015/2015-valero-annual-fmp-update-public-pdf.pdf?la=en

Here is a flare gas recovery plan for the Tesoro Golden Eagle refinery

http://www.baaqmd.gov/~/media/files/compliance-and-enforcement/flares/tesoro-ger-2011-fmp-update-public-rev-091212.pdf?la=en

Zero flare is only possible for circumstance that the refinery plans for there is always a possibility that an event will occur that the flare recovery system cannot handle but many California refineries  achieve zero flaring most if not all of the time.