Evaluasi Produk Oversize Vibrating Screen terhadap Efisiensi Kinerja Pebble Sirkuit Concentrator 130 PT. Amman Mineral Nusa Tenggara Batu Hijau Kabupaten Sumbawa Barat Provinsi Nusa Tenggara Barat

Abstract

Abstract. PT. Amman Mineral Nusa Tenggara has a material processing site that has been milled to get concentrate, where processing is divided into 2 (two) concentrator 106 (plant consentation) and concentrator 130 (plant grinding). PT. Amman Mineral Nusa Tenggara process Copper ore of 120,000 tons/day. Initial processing is done by reducing the size of 130 in contentrator materials (Up-stream) to fit the size for the flotation (retrieval of valuable minerals). In each process in concentrator 130 is done the process of material size reduction where in this process the product that produced there 2 (two) that is oversize product and undersize. The product of oversized trommel screen will be redecorated with pebble crusher to fit the size of material to the size of the ball mill. The results of the test (Cu and Au) of oversized vibrating screen products are still economical to be processed with Cu 0.11% - 0.19% and Au 0.06 ppm - 0.2 ppm. One of the factors affecting high Cu levels on product oversized vibrating screen is WIBM. Where the higher the WIBM then the Cu content of the oversized vibrating screen product is lower.  In the process of reducing the size of the material in pebble circuits almost 300 - 500 tons / day of oversized vibrating screen products are by pass due to limited pebble crusher capacity. This is because the number of oversized vibrating screen products, the oversized vibrating screen product will be returned to the pebble crusher. The effort is to change the setting of CSS pebble crusher from 12 mm to 11 mm so that the target number of pebble crusher products is achieved. Where with 12 mm CSS setting of pebble crusher product achievement 76,3%, after changing the CSS setting 11 mm undersize vibrating screen product increased 10% to 85,5%.

Keywords: Concentrator 130, Pebble Circuit Efficiency, Pebble Crusher, Product Oversize vibrating screen

Abstrak. PT. Amman Mineral Nusa Tenggara memiliki tempat pengolahan material yang telah dilakukan penambangan sampai mendapatkan concentrate, tempat pengolahan dibagi menjadi 2 (dua) yaitu concentrator 106 (plant consentation) dan concentrator 130 (plant grinding). PT. Amman mineral Nusa Tenggara mengolah bijih Tembaga dan Emas sebanyak 120.000 ton/hari. Pengolahan diawal dilakukan proses pengecilan ukuran material di concentrator 130 (Up-stream) sampai sesuai dengan ukuran untuk di flotasi (pengambilan mineral berharga). Pada setiap proses di concentrator 130 dilakukan proses pengecilan ukuran material dimana pada proses ini produk yang hasilkan ada 2 (dua) yaitu produk oversize dan undersize. Produk oversize trommel screen akan dilakukan pengecilan kembali dengan pebble crusher agar ukuran material sesuai dengan ukuran yang di kirim ke ball mill sirkuit. Dari hasil uji kadar (Cu dan Au) produk oversize vibrating screen masih  ekonomis untuk diolah dengan kadar Cu 0,11% - 0,19 % dan kadar Au 0,06 ppm – 0,2 ppm. Kekerasan batuan (WIBM) merupakan salah satu faktor yang mempengaruhi tinggi rendahnya kadar Cu pada produk oversize vibrating screen. dimana semakin tinggi WIBM maka Kadar Cu produk oversize vibrating screen semakin rendah. Pada proses pengecilan ukuran material di pebble sirkuit hampir 300 - 500 ton/hari produk oversize vibrating screen yang di by-pass karena kapasitas pebble crusher terbatas. Hal ini dikarenakan banyaknya jumlah produk oversize vibrating screen, produk oversize vibrating screen akan dikembalikan ke pebble crusher. Adapun upaya yang dilakukan adalah mengubah settingan CSS pebble crusher dari 12 mm menjadi 11 mm agar pencapai target produk pebble crusher tercapai. Dimana dengan settingan CSS 12 mm pencapaian produk pebble crusher 76,3% , setelah mengubah settingan CSS 11 mm produk undersize vibrating screen  meningkat 10% menjadi 85,5%.

Kata Kunci: Concentrator 130, Efisiensi Pebble Sirkuit, Pebble Crusher, Produk Oversize Vibrating screen