What is driving China's ground calcium carbonate capacity expansion and regional clustering?

What is driving China's ground calcium carbonate capacity expansion and regional clustering?
China's calcium carbonate industry reached roughly 70 million tonnes per year of production capacity by end-2022, with ground (heavy) calcium carbonate accounting for 57 million tonnes. Output of heavy calcium carbonate surged from 20 million tonnes in 2016 to 57 million tonnes in 2022, a compound annual growth rate near 19%. Over 700 producers operate nationwide, but capacity is consolidating into large bases in Guangxi (Hezhou, Laibin), Guangdong (Lianzhou), Anhui (Chizhou), Zhejiang (Jiande), Henan (Nanzhao), Jiangxi (Yongfeng), Sichuan (Ya'an) and Hunan (Linwu), with major clusters holding over 70% of capacity. Jiangxi's Yongfeng County alone has 166 non-metallic calcium carbonate enterprises producing 4.2 million tonnes annually—about one-tenth of national output—and hosts Asia's largest ground calcium carbonate producer. Downstream, putty powder, plastics, paper, coatings and artificial stone consume over 90% of heavy calcium carbonate output.