No. 8 Pilot Project: Guizhou Zijin Mining Co., Ltd

Ⅰ Company Profile

The company was established in December 12 and is located in the Zhenfeng County, Southwest Guizhou Prefecture, Guizhou Province. It is a professional gold production enterprise and its core asset, Shuiyindong Gold Deposit, is the third largest monomer gold mine of China at present. The heating atmospheric-pressure chemical pre-oxidation technology that the company itself researches and develops is the first creation both at home and abroad. It successfully solves the international difficulty of Carlin-type gold dressing and smelting and fills the gap of China in the mining technology of primary ore.

Ⅱ Products and Process

The major product of the company is the finished product gold, with the purity of equal to or greater than 99.99%. In 2006, the output is 3131kg. The production process includes breaking, pre-oxidation, carbon-in-leach (CIL), carbon extraction and smelting and so on. The production process is shown in Figure 1.

Figure 1 Process Flow Diagram

Ⅲ CPA Objective and Achievement Status

The cleaner production audit started in Nov, 2008 and ended in May 2009, lasted for seven months. The objective and achievement status of the cleaner production is shown in Table 1.

Table 1 Audit Objective and Achievement Status

Ⅳ Cleaner Production Audit Options and Benefits

Forty-nine cleaner production options have been developed and completed during this round of cleaner production audit, and they are all none/low cost options. Besides, 3 middle/high cost options are listed in the working plan. The major options include strengthening the management of the underground supporting materials, increasing the recycling efficiency of gold-loaded carbon at the bottom of CIL tank, etc. The summary of implementation effects of the options is shown in Table 2.

Table 2 Summary of the Effects of Implemented Cleaner Production Options