Showcasing brilliance in the circular economy

Currently, the contradictions between energy shortages, environmental deterioration, and economic development are becoming increasingly prominent. Adhering to the scientific outlook on development, constructing an environment-friendly and resource-saving "two-type" society, and pursuing a path of sustainable development are important strategic decisions put forward by the 17th National Congress of the Communist Party of China, and are also a necessary choice for the development of human society.

Starting from the harmonious development of enterprises, society, and the environment, Guoda Company aims to improve resource utilization, reduce waste emissions, and achieve clean production. It actively develops and applies new technologies, processes, and achievements, striving to explore and practice new approaches to achieving simultaneous development of resource conservation, environmental protection, and economic benefits, leading the company onto a development track with high technological content, good economic benefits, low resource consumption, and low environmental pollution.

Developing Fine Refining Technology: Challenging the Limits of Comprehensive Utilization

In recent years, with the acceleration of mergers and reorganizations of gold mining enterprises, competition in the gold smelting raw material market has become increasingly fierce, and the complexity of raw material components has also become increasingly apparent. Both internal development requirements and external environmental pressures are encouraging Guoda Company to make full use of mineral resources and conduct extensive exploration in the field of resource recycling.

Driven by technological innovation, Guoda Company has continuously increased its efforts in the development of a circular economy, starting from comprehensive resource recovery and industrial chain extension, challenging the limits of comprehensive resource recovery.

In 2004, Guoda Company invested 150 million yuan to construct a 200,000-ton sulfuric acid and 6000 kw/h waste heat power generation project using its independently developed two-stage roasting and waste heat power generation technology. It uses sulfur from cyanide tailings to produce sulfuric acid, and uses the waste heat generated during sulfuric acid production to generate steam through a waste heat boiler and drive a steam turbine to generate electricity. It can process 250,000 tons of cyanide waste slag annually, produce 200,000 tons of sulfuric acid annually, generate 39.6 million kilowatt-hours of electricity annually, and produce 180,000 tons of iron red as a byproduct.

In 2005, Guoda Company, using its joint venture with Safina of the Czech Republic as a breakthrough, invested 50 million yuan to build the Guoda Safina high-tech environmental protection refining project. By introducing advanced Czech gold and silver refining and deep processing technologies, it refines gold and silver and performs deep processing of precious metals, producing high value-added products such as gold wire, gold salts, silver salts, and silver powder, further extending the gold smelting industry chain.

In 2007, Guoda Company completed a multi-element comprehensive recovery project for tailings with a daily processing capacity of 1000 tons. It recovers valuable elements such as gold, silver, copper, lead, and zinc from smelting tailings. The recovered tailings are further processed to produce high-grade sulfur concentrate as raw material for the sulfuric acid plant. The slag after acid production is processed into pellets and sold as iron concentrate to steel mills, saving the country from importing iron concentrate.

In May 2009, Guoda Company's gold recovery tailings comprehensive utilization project with a total investment of 158 million yuan was successfully completed and put into operation. This project is a newly built comprehensive recovery system integrating the processing of 280,000 tons/year of gold recovery tailings and chemical processing. The main technologies originate from the company's proprietary technologies and patents. Many process technologies have won national and industry science and technology progress awards and were included in the fifth batch of national debt projects for resource conservation and environmental protection in 2007.

Through continuous improvement and innovation, Guoda Company has developed mature multi-element recovery technology, reducing the proportion of traditional gold smelting in the company's economic benefits and increasing the benefits brought by comprehensive resource utilization, accounting for more than 70% of the company's economic benefits.

Carrying out Recycling: Achieving "Turning Waste into Treasure"

Starting from the entire re-production process, Guoda Company treats the waste slag, waste gas, and wastewater comprehensively recovered from each production system as a kind of renewable resource. Through continuous exploration of new processes and the application of new technologies, and by strictly controlling internal circulation, it has achieved resource regeneration from "three wastes," secondary comprehensive recovery, and zero emission of "three wastes."

Focusing on the small amount of valuable elements contained in smelting waste slag at home and abroad, the company has implemented two projects: comprehensive utilization of gold recovery tailings and comprehensive utilization of low-grade associated gold mines. It carries out secondary recycling of smelting waste slag, comprehensively recovering multiple valuable elements such as gold, silver, copper, sulfur, and arsenic. It recycles wastewater during production, uses waste gas for waste heat power generation, and uses waste slag to make building materials, truly achieving "thorough utilization" of ore resources.

With the completion and commissioning of the sulfuric acid power generation project, Guoda Company, while utilizing tailings for acid production and waste heat power generation, has taken waste heat utilization as an important issue in promoting energy conservation and emission reduction for the enterprise. By modifying the original heating pipeline, it uses high-temperature steam and circulating water to replace coal-fired boilers for unified heating of the production area and residential area, and heats the copper liquid in the electrolytic copper production workshop, improving the copper recovery rate and saving more than 2,000 tons of coal annually.

As a major sulfuric acid producer in the Jiaodong region, Guoda Company produces 400,000 tons of sulfuric acid annually. However, the production of one ton of sulfuric acid generates 80-100 kilograms of waste dilute sulfuric acid. The company needs to neutralize more than 40,000 tons of waste acid annually. After feasibility studies, Guoda Company uses the multi-element recovery process of tailings to digest and absorb the waste dilute sulfuric acid discharged from sulfuric acid production. This not only finds a good destination for waste dilute sulfuric acid, saving the company's own sulfuric acid consumption, but also reduces wastewater treatment costs and saves production water.

To improve water utilization efficiency, Guoda Company invested 5 million yuan to introduce Gore membrane filtration technology and built a wastewater treatment system with a daily processing capacity of 1500 tons. After treatment, all the company's production wastewater is returned to the production system as process water for processes such as slurry preparation and washing. This not only reduces water demand and alleviates water pressure, but also achieves zero discharge through a semi-closed cycle of water resources that undergoes "utilization-treatment-reuse-retreatment-recycling." In the process of treatment and recycling, trace amounts of valuable elements such as gold, silver, and copper in the wastewater are further recovered.

Constructing "One Plant, Two Zones": Promoting Industrial Transformation and Upgrading

In 2010, in accordance with the overall requirements of the Zhaoyuan Municipal Party Committee and Municipal Government to "attract gold concentrates from outside the city for smelting in Zhaoyuan, actively carry out multi-element recovery, vigorously develop associated minerals, follow up and expand the smelting field, and build a first-class gold smelting production base in China and even the world," Guoda Company actively explored strategic transformation and structural optimization, and put forward and formulated the grand goal of the "One Plant, Two Zones" revitalization plan.

The so-called "One Plant" refers to investing a certain amount of funds to carry out technological transformation of the existing plant area, improve the level of modern equipment, and achieve overall industrial upgrading. The so-called "Two Zones" refers to planning the construction of a new industrial zone for the smelting company's independent innovation and a small and medium-sized ecological industrial park.

The smelting company's self-developed industrial innovation zone, as part of the "one factory, two zones" revitalization plan, covers a total area of approximately 500 mu. Projects in the new zone emphasize "strategic transformation and structural optimization." The 100,000-ton/year comprehensive utilization project for low-grade multi-element resources is an environmentally friendly circular economy project primarily processing various gold and non-ferrous metal smelting tailings, with an annual processing capacity of 100,000 tons. The 300,000-ton/year low-grade silver-bearing zinc ore smelting project represents a transformation from the gold industry to the non-ferrous zinc industry. This project uses low-grade zinc ore as raw material, employing cyanidation, rotary kiln roasting, and hydrometallurgical zinc smelting technologies, with an annual production of 30,000 tons of high-quality zinc ingots. The 200,000-ton/year S-NPK compound fertilizer project is a downstream development of sulfuric acid production and a transformation from the smelting industry to the chemical industry, consuming 200,000 tons of sulfuric acid annually. The construction of small and medium-sized ecological industrial parks is mainly based on government planning and enterprise development needs, involving the relocation of the current Yantai Longxiang Grape Wine Co., Ltd., with the original winery site used for real estate development.

The Guoda Company's "one factory, two zones" revitalization plan has a planned total investment of 1.2 billion yuan and a construction period of 3 years. Currently, the preliminary preparations for the park construction project are progressing smoothly and in an orderly manner, with construction expected to begin in the second half of this year. After the completion and commissioning of the new zone, sales revenue will increase by 2 billion yuan.

Developing a circular economy drives the continuous extension of Guoda Company's industrial chain to a deeper level. Currently, the company has formed three major industrial clusters centered around gold smelting, cathode copper smelting, and sulfuric acid chemical industry. The path of scientific development leads Guoda Company to make rapid progress in the fields of resource conservation, environmental protection, and circular economy.