Looks like the woodgas bug flew to Iran!
I agree with Andy.
Slovenia, where l live, is 62% forest cowered. Wood is abundant. Others from around the world may not be so lucky…
Allso, l think gasifiing a tire that wuld otherwise be poluteing the enviroment in some dumpyard is a good idea.
And, as a bonus, some tire latex is still of tree origin
I have no dubt clean, rich gas can be made out of tires!
One way is to relort it, like Bob sayd, but l think l wuld rather add shreaded tires to a charcoal gasifier hearth.
The only problem l see is shreading the tires, and extracting the wires.
For engine grade gas, and any gas for that manner, it wuld be wery inportant to desulfurise (extract sulfur out of the gas). This can easyaly be done with a scrubber with a lime solution in. Lime will atract sulfur and form calcium sulphate, plaster.