306
C. Chen et al.
Summary and Analysis
(1) The development of the overall life cycle of non-ferrous metal smelting projects
in China is still in its infancy. Among the three mentioned demonstration
projects, two are the general contracting projects of our company, CINF. We
have continuously participated in, followed up, and paid a return visit to each
stage of the project: from the preliminary investigation and project approval,
conceptual comparison and selection, design, procurement, construction, to the
production standard completement.
(2) For the purpose of reducing sulfur dioxide emission pollution and improving
recycle rates of rare metals, Danxia smelter implemented a technology adopting
the oxygen leaching process to convert sulfur compounds in the concentrate
generating elemental sulfur. This prevents air pollution caused by sulfur dioxide
by pyrometallurgical smelting processes and greatly improved recycle rate of
rare metals. In the process of leaching, all kinds of secondary residue materials
can be subsequently treated in a flash smelting process to achieve zero discharge
of waste slag pollution.
(3) The Zhuzhou smelter project takes the original system of smelting technology
in conjunction with equipment upgrades as a starting point, to reduce the waste
residue discharge and operating cost, along with efficiency increasing. It not
only processed almost all of the secondary materials from the old conventional
leaching system, but in addition a variety of purchased low grade raw materials
can be treated. It assisted Zhuzhou in solving the problems about existing methods of secondary stockpiling of the excavated debris and resulted in considerable
economic benefits.
In Hechi Southern’s triple furnace project, the continuous operation of side blown
oxygen-rich smelting furnace in lead-related smelting process was implemented for
the first time on a commercial scale, and the treatment of antimony anode slime
with low silver lead was accomplished. The furnace system effectively reduces the
operating intensity for workers and improves the operating environment, which is of
great reference significance to other smelting operations.
The above three demonstration projects all focus on comprehensive utilization
of secondary materials, reduction of waste emissions, reduction of consumption,
and efficiency increasing. In the design and operation stage, the basic process flow
and equipment have been upgraded to different degrees. To realize environmentally
friendly smelting projects and improving the companies’ economic situation, the
entire process including equipment performance, product quality, product structure,
and other factors cannot be accomplished by ordinary process changes starting from
raw materials and ending with crude metal production and subsequent refining processing. The entire process chain needs to be adjusted and synchronized, as one of
the key points of the entire life cycle.
C. Chen et al.
Summary and Analysis
(1) The development of the overall life cycle of non-ferrous metal smelting projects
in China is still in its infancy. Among the three mentioned demonstration
projects, two are the general contracting projects of our company, CINF. We
have continuously participated in, followed up, and paid a return visit to each
stage of the project: from the preliminary investigation and project approval,
conceptual comparison and selection, design, procurement, construction, to the
production standard completement.
(2) For the purpose of reducing sulfur dioxide emission pollution and improving
recycle rates of rare metals, Danxia smelter implemented a technology adopting
the oxygen leaching process to convert sulfur compounds in the concentrate
generating elemental sulfur. This prevents air pollution caused by sulfur dioxide
by pyrometallurgical smelting processes and greatly improved recycle rate of
rare metals. In the process of leaching, all kinds of secondary residue materials
can be subsequently treated in a flash smelting process to achieve zero discharge
of waste slag pollution.
(3) The Zhuzhou smelter project takes the original system of smelting technology
in conjunction with equipment upgrades as a starting point, to reduce the waste
residue discharge and operating cost, along with efficiency increasing. It not
only processed almost all of the secondary materials from the old conventional
leaching system, but in addition a variety of purchased low grade raw materials
can be treated. It assisted Zhuzhou in solving the problems about existing methods of secondary stockpiling of the excavated debris and resulted in considerable
economic benefits.
In Hechi Southern’s triple furnace project, the continuous operation of side blown
oxygen-rich smelting furnace in lead-related smelting process was implemented for
the first time on a commercial scale, and the treatment of antimony anode slime
with low silver lead was accomplished. The furnace system effectively reduces the
operating intensity for workers and improves the operating environment, which is of
great reference significance to other smelting operations.
The above three demonstration projects all focus on comprehensive utilization
of secondary materials, reduction of waste emissions, reduction of consumption,
and efficiency increasing. In the design and operation stage, the basic process flow
and equipment have been upgraded to different degrees. To realize environmentally
friendly smelting projects and improving the companies’ economic situation, the
entire process including equipment performance, product quality, product structure,
and other factors cannot be accomplished by ordinary process changes starting from
raw materials and ending with crude metal production and subsequent refining processing. The entire process chain needs to be adjusted and synchronized, as one of
the key points of the entire life cycle.