just stay calm and let him scream it out don't show him he is bothering you when he is ready from screaming just insist on him doing what he is told(like he never screamed) don't give any importance to the screaming. the probability is he'll scream more at first to have your attention when he sees that it's not taking him anywhere he will stop eventually.praise him when he do as he's told without screaming.

22 month olds are not designed to sit still and its unreasonable to ask them to do so particulary in a situation that is of absolutely no interest to them at all.

Either get a sitter for him or find somewhere he can play while the adults chat and eat.