Abstract: In order to fully recover the copper and cobalt resources in a copper-cobalt sulfide ore in Congo（DRC），in view of the fact that the proportion of magnesite in the ore is 46.62%，the total proportion of layered silicate minerals such as talc and chlorite is 13.90%，and it is easy to slime，which leads to the problems of large middle ore circulation，serious loss of fine-grained lean intergrowth and poor flotation in⁃ dex in the conventional one-roughing three-scavenging three-cleaning process，based on the conventional process（Scheme 1），the combined regrinding and re-concentration process of middle ore（Scheme 2）is proposed，and the flotation test is carried out.In scheme 2，the full dissociation of fine-grained poor inter⁃ growth is realized by the combination and regrinding of middle ore，and CMC is used to inhibit layered sili⁃ cate minerals，which effectively reduces the adverse effects of gangue such as talc and chlorite.The results of the whole process closed-circuit test show that under the condition of 1.92% Cu and 0.97% Co in the raw ore，the copper-cobalt sulfide concentrate with Cu grade of 21.94% and Co grade of 10.99% is produced in the scheme，and the recovery rates of Cu and Co are 93.27% and 90.42%，respectively.The indexes are sig⁃ nificantly better than that of scheme 1，and the efficient recovery of high carbonate type copper cobalt sul⁃ fide ore resources is realized，and the economic benefit is remarkable.

Key words: copper-cobalt sulfide ore, flotation, regrinding and re-concentration of middle ore, CMC