Combine beer, seafood seasoning, and salt in a large saucepan or stockpot over medium-high heat. Squeeze juice from both lemon halves into the beer mixture and add both rinds to the beer. Stir and bring to a boil. Cover the pot and boil for 10 minutes.

Add shrimp to boiling liquid, cover again with the lid, and turn off the heat. Transfer shrimp to serving bowls when they are bright pink on the outside and the meat is opaque, about 3 minutes.