A B S T R A C TBeneficiation of low-grade gold and silver ores were investigated by gravity concentration flotation methods. The ores were obtained from Way Kanan Region and Mount Burhan in Province of Lampung. In this study, gravity concentration in sluice box and flotation were performed in sequence. Effect of particle size was investigated in gravity concentration by sluice box. Furthermore, effect of various parameters in flotation operation such as concentration of collector, ore particle size, and processing time were studied. Gravity concentration in sluice box indicated that the highest recovery of gold and silver were 76.52% and 94.83%, respectively when using ore particle size of 100+150 mesh. Flotation experiments showed that the maximum recoveries of gold and silver obtained were 98.33% and 86.42%. The conditions to obtain maximum recovery in this study were -100+150 mesh of ores particle size, 25 mL/kg concentration of collector, and 25 minutes of processing time.Keywords: beneficiation; flotation, gold ore; silver ore; sluice box.A B S T R A KBenefisiasi bijih emas dan perak kadar rendah menggunakan konsentrasi gravitasi dengan palong dan menggunakan flotasi telah dilakukan. Bijih emas dan perak yang digunakan berasal dari daerah Way Kanan dan Gunung Burhan di Provinsi Lampung. Pada penelitian ini, konsentrasi gravitasi dengan palong dilakukan terlebih dahulu sebelum dilakukan benefisiasi menggunakan flotasi. Pengaruh ukuran partikel dipelajari pada konsentrasi gravitasi dengan palong. Sedangkan pengaruh beberapa variabel seperti konsentrasikolektor, ukuran partikel, dan waktu flotasi dipelajari dalam proses benefisiasi menggunakan flotasi. Pada konsentrasi gravitasi dengan palong, hasil percobaan menunjukkan bahwa persen recovery emas dan perak tertinggi secara berturut-turut adalah 76,52% dan 94,83% ketika digunakan ukuran partikel -100+150 mesh. Pada proses flotasi, hasil percobaan menunjukkan bahwa persen recoveryemas dan perak maksimum yang diperoleh adalah 98,33% dan 86,42% ketika digunakan ukuran partikel -100+150 mesh, konsentrasi kolektor 25 mL/kg dan waktu flotasi 25 menit.Kata kunci: benefisiasi; emas; flotasi; palong; perak
ENRICHMENT OF LOW GRADE MAGNETITE ORE BY MAGNETIC AND GRAVITY SEPARATIONS: EFFECT OF PARTICLE SIZE
