Study on flocculation sedimentation of copper tailings slurry and its effect on solidification
To investigate the flocculation and sedimentation effects of different single and composite flocculants on copper tailings slurry,traditional inorganic flocculant aluminum sulfate,polymeric inorganic flocculant polyaluminum chloride(PAC),and organic flocculant anionic polyacrylamide(APAM)were selected for experiments.Both single-flocculant tests using all 3 flocculants and composite-flocculant tests using the 2 inorganic flocculants mixed with APAM were conducted.Subsequently,the flocculated copper tailings slurry was tested for cement solidification.Results show that,under the same dosage,the flocculation performance of the 3 flocculants follows the order of APAM>PAC>aluminum sulfate.In the composite tests,the optimal combination of each flocculant resulted in better sedimentation than using them individually.The compressive strength of the solidified copper tailings after flocculation increased by a minimum of 2.4 times at all curing ages.Among the single flocculants,the copper tailings solidified with aluminum sulfate exhibited the highest compressive strength at all curing ages,while APAM had the lowest.For composite flocculants,the combination of aluminum sulfate and APAM produced a higher compressive strength in the solidifiied copper tailings compared to the PAC and APAM combination.