Saudi Arabia’s average size is 250,000 BPD.
Saudi Aramco’s four domestic refineries, at Riyadh, Ras Tanura, Yanbu’ and Jiddah, have a combined capacity of nearly 1 million barrels per day. Adding the company’s two domestic joint-venture refineries, with ExxonMobil in Yanbu’ (SAMREF) and with Shell in Jubail (SASREF), and the company’s share of refining capacity at Petro Rabigh, brings in-Kingdom refining capacity to roughly 1.5 million barrels per day.
I believe the following is correct averaging much smaller:
Iran
Abadan Refinery, 450,000 BPD
Arak Refinery, 150,000 BPD
Tehran Refinery, 225,000 BPD
Isfahan Refinery, 265,000 BPD
Tabriz Refinery, 112,000 BPD
Shiraz Refinery, 40,000 BPD
Lavan Refinery, 20,000 BPD
Bandar Abbas Refinery, 232,000 BPD
Kermanshah refinery, 21,000 BPD
Iraq
Basrah Refinery, 126,000 BPD
Daurah Refinery, 100,000 BPD
Kirkuk Refinery, 27,000 BPD
Baiji Salahedden Refinery, 140,000 BPD
Baiji North Refinery, 150,000 BPD
Khanaqin/Alwand Refinery, 10,500 BPD
Samawah Refinery, 27,000 BPD
Haditha Refinery, 14,000 BPD
Muftiah Refinery, 4,500 BPD
Gaiyarah Refinery, 4,000 BPD
The link shows hiogher numbers plus indicates a lot of plans for greatly increasing capacity.