iv STUDY ON MINIMIZE ENVIRONMENTAL POLLUTION IN SMALL SCALE GOLD ORE PROCESSING

• Main Author: (NIM : 125 06 034), SATORI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/24232
• Institution: Institut Teknologi Bandung

Amalgamation waste pollution in small-scaled gold mining sites in Buni Kasih, Pangalengan, Bandung District is very high. Based on the results of analysis on samples of water and soil, mercury levels ranged from 0 ppb - 16.98 ppb in water samples and 8.6 ppm - 146 ppm in soil samples (first stage of sampling) and 8 ppm - 107 ppm (second stage of sampling). This value has exceeded the government-determined threshold (0.001 ppm - 0.005 ppm). High levels of mercury due to the direct discharge of waste into the river amalgamation. In addition, the amalgamation treatment done simultaneously with the amalgamation milling (direct amalgamation) result in the amount of mercury wasted along with the tailings tended to remain high and gold recovery tended to be low. To reduce this impact, one way is to apply the indirect amalgamation in which the amalgamation is done after milling. With this method, the expected loss of mercury can be reduced and the recovery gold tend to increase. Based on the analysis of AAS (Atomic Absorption Spectrophotometer) on gold ore samples indicate that the ore sample has a low gold content (4.266 ppm) and high silver content (245.91 ppm). This showed that ore samples have gold content less than the requirements to be amalgamation (8 g/tonne). As a result the amalgamation which carried out on samples of gold ore can not produce amalgam. The amount of feed is relatively low (1 Kg - 2 Kg) and a relatively high (53 rpm) is also possible to be the cause in amalgam was not formed. Amalgamation success depends on several factors, they are: ore mineralogy, rotation perminute, solid percentage, pH of pulp, contact time, and the number of grinding material.