China’s Aluminum Output Surge Tests Capacity and Demand Limits

Chinese aluminum smelters are running hot — and starting to test both capacity constraints and limitations on demand.

Daily output in the world’s biggest producer hit an all-time high of 129,000 tons last month, propelled by record margins and a global shortage of the metal caused by the war in Iran. Citigroup Inc. expects prices to rally further as the market contends with its biggest supply shock in 50 years.