On September 17, the completion acceptance of the 8000t/d Beneficiation Extension Project, designed by ENFI, was conducted in the Dulong Mine of Yunnan Hualian Zinc & Indium Stock Co., Ltd.. Mr. Cao Yuanqing, the Party Secretary and Chairman of the Company expressed his satisfaction with the project construction quality in his speech at the event and showed gratitude to every construction party for their hard work. He also highly praised ENFI designer team for their efforts in optimization of design scheme and construction services, especially in rationally optimizing the design scheme of tailings dam in Dagou of Tongjie by the professional designers in tailings, which reduced embankment quantity by one million cubic meters, saving nearly RMB17 million.

Located in Wenshan Prefecture, Yunnan Province, Yunnan Hualian Zinc & Indium Stock Co., Ltd. is a state-owned holding enterprise engaged in mining, beneficiation and smelting. Its Dulong Mine is rich in mineral resources, including a variety of recyclable metals, among which the reserves of indium, a rare precious metal, rank the first, tin the third in China, and zinc reserves come third in Yunnan province. The 8000t/d concentrator extension project in Dulong Mine is one of key construction projects of 2011 “Three One-Hundred Projects”, and also a major strategic development project of Yunnan Hualian Zinc&Indium Stock Co., Ltd..

ENFI completed feasibility study of this project in 2008, finished basic design in 2011 and afterwards the construction drawings. The 8000t/d concentrator features single  production system, advanced SAB technological process in crushing process, and a combined separation process (flotation-magnetic separation-gravity separation) , of which flotation for copper, zinc and sulphur recovery, magnetic separation for iron recovery and flotation-gravity separation combined process for tin recovery, in such a way realizing comprehensive recovery of zinc, indium, tin, copper, silver, iron and sulphur. The project, a copper-zinc-tin polymetallic ore concentrator designed by ENFI, is characterized by complex technology, a variety of minerals, being the largest tin polymetallic ore concentrator in terms of single production system in China. In particular, both table quantities and table layout in gravity separation of tinstone process were pioneering in China, with 714 tables and overlap of three layers to save space. The design gained praise from the Owner and fully embodied ENFI’s concept of innovation.

The project design includes the new 8000t/d concentrator, tailings pond in Dagou of Tongjie, Xin Tian tailings pond and public auxiliary facility. It produces six types of minerals, with complex technological process, limited construction space, poor engineering geological condition and great difficulty in construction. The project officially began in May of 2012 and went into operation successfully on September 10, 2013 with joint effort from all construction parties and overcoming numerous difficulties. It achieved design capacity in only 3 months after operation. All products, except for Tin, met or even exceeded their respective design objectives. The project passed completion acceptance after almost one year’s trial operation. The construction standard of the concentrator is leading-edge internationally and first-class nationally.