The entire package of sanction will come into effect on November which are related on Iran’s oil export and petrochemicals (any oil related product).
The sanctions on 6 August were on these matters:
Iranian economy is 34% dependent on oil but sanctions won’t be any more effective than When Obama imposed them. The only different now is that anyone who doesn’t comply with sanctions appear as hero and those who do comply appear as stooges. No one respect and is on board with the US.
It is really quite remarkable… now we have a situation in which EU is blocking the US on sanctioning the Eu companies!
“The Blocking Statute allows EU firms and individuals doing legitimate business in Iran to recover damages arising from the US sanctions and nullifies the effect in the EU of any foreign court ruling based on them. In addition to shielding EU companies, the Blocking Statute forbids EU persons from complying with the US sanctions, unless exceptionally authorised to do so by the European Commission.”( Iran Deal: EU to shield EU companies from re-imposed US sanctions – EEAS – European External Action Service – European Commission)
China will too continue its business with Iran along with India, Turkey, Pakistan and many other countries.
Iran economy will not collapse in the sense you think.
But ordinary people will sure feel more pressure at least at the beginning of the sanctions.