How does China's coal-based urea cost structure shield domestic prices from global spikes?

How does China's coal-based urea cost structure shield domestic prices from global spikes?
China produces roughly 80% of its urea via coal gasification, with nominal capacity near 74.3 million tonnes per year, about 30% of the world total. Because feedstock is domestic coal rather than imported gas, Chinese prices stayed anchored near 1,750-1,880 RMB/t, with Shandong, the national benchmark, holding at 1,830-1,840 RMB/t. Meanwhile overseas prices rose about 90%, widening the import-export spread to roughly 3,000 RMB. China tightened export quotas to 3.3 million tonnes for the year, down 32.7%, prioritizing domestic farmland. Russia, another major exporter, also restricted shipments.