Comprehensive Utilization of Jiangxi Tailings Resources and Research on Circular Economy

In the process of China's economic development, 95% of energy and 85% of raw materials come from mineral resources. After years of development and utilization of mineral resources in Jiangxi Province, there has been a situation in which the degree of resource security has decreased and new replacement resources have been scarce. According to the data, all the minerals discovered in Jiangxi Province are converted into potential economic value, which is only 1.3% of the national total; the average occupancy of 45 major minerals is 21.7% of the national per capita possession. It is estimated that by 2020, there will be resource crises in 40 important mines in Jiangxi Province, including 22 in severe crisis, 11 in moderate crisis, and 7 in mild crisis. By then, there will be more than 20 kinds of mineral resources. Meet the needs of economic construction and social development... At the same time, the large amount of waste rock and tailings produced by the development and utilization of mineral resources for many years not only caused a lot of waste of resources, but also seriously polluted the ecological environment. How to face this contradiction, strengthen the comprehensive utilization of tailings resources, on the one hand, make the tailings resources and turn waste into treasure; on the other hand, the occupied land is treated and the ecological environment is developed.

I. Current status of comprehensive utilization of tailings resources

     Jiangxi province is China's mineral resources, mineral resources are very rich, and many kinds of various types have been found 160 kinds of minerals, including copper, tungsten, tantalum, niobium, uranium, rare earth resources in Jiangxi Province is known as the "five golden flowers" in the country's total reserves, Jiangxi copper, 25%, 26% niobium, tantalum, tungsten, uranium, rare earth and other mineral reserves and production at home and abroad also has certain advantages, great potential value of the resource. There are 7,070 various types of mining enterprises in Jiangxi Province, 75 kinds of minerals with large-scale development and utilization, and the total amount of ore opened in the year reaches 256 million tons. However, at the same time, rich ore and rich ore are another major feature of Jiangxi's mineral resources. After the ore dressing , a large number of tailings are produced. According to statistics, as of the end of 2004, the cumulative storage of waste rock in Jiangxi Province was 1.375 billion tons, and the accumulated storage of tailings was 1.321 billion tons. . This not only causes a lot of waste of resources, but also acidification of tailings acidification, and the dissolution of non-ferrous metal ions into the ground, causing serious pollution and damage to land, water resources, atmosphere, animals and plants. In addition, in order to stack and dispose of these tailings, enterprises must establish corresponding tailings dams, and the construction, maintenance and management of tailings dams still require a large amount of expenses. According to estimates, the capital cost per ton of the metallurgical mine tailings pond in Jiangxi Province It is 2 to 3 yuan, and the production and operation management fee is 3 to 6 yuan. As the number of tailings continues to increase, it is becoming a burden on enterprises. Therefore, strengthening the recycling of tailings resources in Jiangxi Province and promoting the coordinated development of economic, social and environmental benefits of mining enterprises are important issues that we must face and solve. However, the total recovery rate of mineral resources in Jiangxi Province is currently about 30%, and the recycling rate of tailings is about 10%, which is about 20% and 40% lower than that of Western developed countries. Moreover, the use and utilization of tailings resources is also very limited, mainly in the following aspects:

(1) Recycling valuable components

Tailings utilization process is the most direct method of recovering the useful substance, and wherein the associated elements, present, Jiangxi recovered from the tailings of valuable minerals are mainly pyrite, magnetite, copper minerals, chromite , sericite, dolomite and so on. For example, Yongping Copper Mine 1# tailings mine tailings piled nearly 3 million tons, the surface has been oxidized, measured, the natural pH value is 4.08, the pH value is changed to 6-7 by lime slurry, plus butyl yellow The drug, 2 ^# oil, two coarse and two sweeps of single floating sulfur, obtained 6.25% of the original ore sulfur grade, 40.81% of the sulfur crude ore grade, and the recovery rate was 79.20%.

Silver lead zinc mine Hill tailings inventory more than 10 million t, and the new tailings discharged into the year 500 000 t, tailings sericite content of 29% to 34%, and most were single, fine-grained. The mine began to recover sericite from 1994. It can process 50,000 tons of tailings every year. Now it has been converted from a pilot plant to a production plant, and has achieved production and sales of 900 tons of sericite powder. It uses the beneficiation method to recover sericite, floats the methane after floating ore, and obtains the concentrate grade >62%, and the recovery rate is about 60%. Further, Dexing Copper and Copper WUSHAN recovery of valuable components copper, gold and silver and other precious metals, and sulfur from the tailings; Great I Tungsten Bismuth recovered from the tailings so achieved good economic benefits.

(2) Tailings are used in building materials production

Another important way to comprehensively utilize tailings is to produce building materials based on the physicochemical properties of the waste. Generally, non-ferrous metal tailings can be divided into three categories according to their main components: one is tailings containing quartz sand, which can be generally used to produce steam-pressure silicate ore bricks; the other is mainly composed of calcite and limestone . The tailings can be used as the main raw material for the production of cement; the third is the tailings with high SiO ₂ and Al ₂ O ₃ can be used to produce refractory materials. There are many examples of using the tailings resources to produce building materials in the province. For example, Yinshan Lead-Zinc Mine and Xihuashan Tungsten Mine use tailings sand to produce and process calcified bricks and concrete products; Dexing Copper Mine uses tailings, loess, feldspar , calcium carbonate and Raw materials such as talc are used to produce low-temperature colored glazed exterior wall tiles; Yichun antimony ore uses lithium mica to extract raw materials of lithium salt and lithium hydroxide, and then directly applied to ceramics and glass industry. In addition, rare earth tailings is a new type of porcelain making material. It can be used for both tires and glazes, celadon and white porcelain. The rare earth tailings are a natural color glaze.

(3) Filling the underground goaf with tailings

The use of coarse sand filled tailings to fill the goaf is one of the earliest and most extensive methods for the comprehensive utilization of tailings. The cost is 1/4 to 1/9 of the hydraulic crushing method, especially for some Mining enterprises that cannot limit the construction of tailings ponds are more realistic. For example, the Dongxiang Copper Mine built the 7# ore body filling system as early as 1987, and consumed 70-80,000 tons of tailings annually, accounting for about 1/3 of the tailings. At present, most of the scale mining enterprises in Jiangxi Province are planning to use part of the tailings to fill the underground goaf.

(4) Carrying out land reclamation

Reclamation is a subsequent treatment for tailings ponds or dumps. It is divided into two parts: engineering reclamation and biological reclamation. The bioremediation stage is to carry out biological transformation, ecological reconstruction and biological production in the environmental system established by the engineering reclamation. The two phases are interdependent and integrated. The project reclamation has two forms: reclamation and reclamation. Among them, the addition of the soil, such as the Dongxiang copper mine, covers the loess cover, planting grass and acid-resistant masson pine, reducing the loss of tailings. The tree has become a forest. Vegetation restoration was carried out according to the special site conditions of pure tailings, and the pioneering herb screening test was carried out on the unearthed tailings pond. The results showed that there were 7 pioneer herb plants. Settling growth on the tailings accelerates the natural succession of vegetation restoration. In addition, in view of the poor physical and chemical properties of the abandoned land and the high content of heavy metals, the mine inoculation can also be achieved through the inoculation technique of “inoculation of cockroaches on the tailings, enrichment of toxic substances, improvement of soil and removal of toxic substances”. Ecological restoration and sustainable use of the land.

2. Inadequacies in the comprehensive utilization of tailings resources

Although through continuous efforts, the comprehensive utilization of tailings resources in Jiangxi Province has achieved certain results, but in fact it is still in its infancy. At present, the total recovery rate of mineral resources in Jiangxi Province is about 30%, and the recycling rate of tailings can only reach about 10%, which is about 20% and 40% lower than that of Western developed countries, which is far from adapting to the economic and social conditions of Jiangxi Province. There are still many shortcomings in the development and the needs of the company's own development, focusing on the following aspects:

(1) The awareness of tailings resource utilization is weak

Many mining enterprises in Jiangxi, especially small and medium-sized mining enterprises, have not fully realized the importance of comprehensive utilization of tailings to the sustainable development of mining enterprises, especially for loss-making mining enterprises and resource-exhausted mining enterprises. The extensive development model of “high mining, low utilization and high emission” is still adopted. It is not seen that the tailings contain a lot of useful resources. It is a kind of labor that has been condensed with a lot of funds and labor after various processes. Mineral deposits and secondary resources can be transformed into useful products with only a little extra effort, bringing considerable economic and environmental benefits to the company.

(2) The system is not perfect and the management is not standardized

The concept of advocating the comprehensive utilization of tailings has been proposed for many years, but as of September 2007, it is still in the stage of propaganda and education. It has not formed a sound legal, regulatory and policy system, and there are many systems that are absent and misplaced. In addition, even if there are relevant institutional arrangements in some aspects, due to the irregular management, some of the systems are ineffective and ineffective. As a result, some tailings resources are not effectively utilized, resulting in waste of resources and environmental pollution.

(3) Insufficient technological innovation

The comprehensive utilization of tailings is an activity process that is highly dependent on technology. At this stage, the technical research and development of the comprehensive utilization of tailings in Jiangxi Province still adopts the development model of mining enterprises, research institutes and universities and colleges, and lacks long-term development. And stable communication and cooperation. As a result, the R&D strength is weak, and some key technology or technical bottlenecks cannot be effectively broken. As a result, the comprehensive utilization rate of tailings is low, and some valuable elements in tailings cannot be recycled efficiently and perform poorly in the production of high-grade, high value-added products using tailings.

(4) Insufficient capital investment

The tailings comprehensive utilization project is not fully guaranteed in terms of funds, and the investment is seriously insufficient. Whether it is the special support of public finance, the policy tilt of national fiscal and taxation leverage, or the active participation of social capital, it is far from the actual demand. Moreover, the current financing channels for tailings comprehensive utilization projects are very narrow, and special financing through various financial instruments is also very limited. In addition, most of the mining enterprises in Jiangxi Province have a poor performance. Some mining enterprises have been in a state of loss for a long time, and the investment of their own funds is insufficient.

Thoughts on Accelerating the Comprehensive Utilization of Tailings Resources under the Mode of Circular Economy

The circular economy model is an economic development model characterized by simulating the ecological community material cycle, with the material recycling and recycling. The circular economy aims to achieve sustainable development, with the efficient use and recycling of resources as the core, the principle of “reduction, reuse and resource utilization”, and the principle of “low mining, high utilization, low emissions”. Characteristics, reconstruction and composition of a "resource-product-renewable resource" material repeated cyclic flow process. It fundamentally reduces the sharp contradiction between economic development and environmental protection for a long time, obtains maximum economic benefits and environmental benefits at the lowest cost, realizes the sustainable use of resources, and realizes the harmonious development between man and nature. Therefore, in order to implement the scientific development concept and realize the guarantee and support of mineral resources for economic development, we must follow the development model of circular economy and accelerate the comprehensive utilization of tailings resources.

(1) Establishing a new concept of comprehensive utilization of tailings

The competent departments of mineral resources and mining enterprises should base on the long-term strategic considerations and base on the development model of circular economy, and recognize the comprehensive utilization of tailings resources as a necessary measure to achieve sustainable development of the mining industry. At the same time, it pays attention to scientific planning and establishes a new concept of the overall utilization of tailings resources. On the one hand, according to the reserves and distribution of Jiangxi Province's superiority and characteristic mineral resources, a group of large-scale enterprise groups for comprehensive utilization of tailings will be set up in a targeted manner to concentrate on the development and comprehensive utilization of professional tailings. On the other hand, in view of the characteristics of small-scale mining enterprises in Jiangxi Province, low intensiveness and low comprehensive utilization of resources, a specialized tailings comprehensive utilization enterprise with independent legal person status will be established in the relatively concentrated areas of these small mining enterprises. Through the separation of the “tailing body” and the “little tail body”, the unity of the “little tail body” and the “beneficiary body” is realized, and the market supply and demand relationship is established between the mining enterprise and the tailings utilization enterprise.

(II) Improve the system construction of comprehensive utilization of tailings

1. Improve laws, regulations and related policy systems

The "Ministry of People's Republic of China Mineral Resources Law" promulgated in 1986 in China has not been able to fully adapt to the needs of the development of the new situation. The "Regulations on the implementation of the mining circular economy in Jiangxi Province" should be formulated according to the actual conditions of Jiangxi Province, and relevant laws, regulations and policy systems should be gradually improved. At the same time, strengthen coordination and cooperation between laws and regulations, enhance its operability, enforce clean production audits according to law, strengthen law enforcement inspections of energy conservation and emission reduction and tailings utilization, strictly implement environmental impact assessment systems, and continuously improve the quality of economic operations. Improve the ecological environment; enable the comprehensive utilization of tailings in Jiangxi to be incorporated into the legal track.

2. Formulate and improve the standard system for comprehensive utilization of tailings

Based on recycling economy development model and the "3R" principle, the establishment of metallurgy, the minimum quantitative criteria nonferrous metals, chemicals, building materials, coal, nuclear industry, local gold mines and mine tailings and implementation details; the development of comprehensive utilization of tailings classification criteria, tailings Resource feature detection method standards, tailings analysis test and sampling method standards, tailings development and utilization technical standards, and so on.

3. Establish tailings resources and environmental impact assessment system

According to the requirements of circular economy and full utilization of resources, tailings is regarded as a special exploration object, and the physical and chemical properties of the substances contained in it are comprehensively analyzed; the occurrence status, distribution, selectivity and economic benefits are scientifically evaluated; Systematic analysis and evaluation of the possible environmental impacts.

(3) Strengthening the scientific and technological research efforts on the comprehensive utilization of tailings

The comprehensive utilization of tailings is a complex system engineering, which requires high technical support. It is difficult to achieve good results by relying solely on one unit. It is recommended to set up the Jiangxi Province tailings comprehensive utilization engineering technology center, and set up a research and development center, a results transformation center and an international exchange center.

The main function of the R&D center is to build a provincial-level scientific research technology platform, integrate the scientific and technological forces of the mining and mining units, mining and metallurgical enterprises, scientific research institutes and universities and colleges, and implement the joint research mode of “small center and large network”. The key technologies in the comprehensive utilization of the mine and the breakthrough of relevant technical bottlenecks.

The main function of the Achievement Transformation Center is to actively guide the transformation of scientific research results to real productivity for mining enterprises, market-oriented and society-oriented, and strive to shorten the cycle of achievement transformation. According to the actual production needs of enterprises, we will carry out scientific research and results in a targeted, tailored and systematic manner. Conversion. Improve the maturity, support and engineering level of research results.

The main function of the International Exchange Center is to actively carry out international exchanges and cooperation in technology, management, talents and capital around the tailings comprehensive utilization project. Including tailings management system, personnel training, standard system construction; joint research on tailings overall utilization and clean production technology, development of high-tech products and product testing technology technical cooperation; introduction of advanced production equipment, testing equipment, absorption and development Exchanges and cooperation in demonstration projects, technical investment in demonstration mine projects, and capital investment.

(4) Strengthening the design and development of “no tail, less tail” mines

According to the requirements of the "China's 21st Century Agenda Priority Project", in accordance with the development model of circular economy, the existing mine tailings will be comprehensively utilized, and the design and development of the "no tail, less tail" mine will be implemented for the new mine. Reduce the tailings emissions from the source, and then achieve the ultimate goal of saving resources, reducing pollution, and protecting the environment. In this regard, some enterprises in Jiangxi Province are worth learning and learning. For example, Yichun Yankuang develops through the “small tail” process, and after the tailings are re-selected by advanced technology, the final tailings treated by desliming are used to make glass and micro. The raw materials of crystal glass have basically realized the production of “small tail” mine. Strive to build one-third of the mines in Jiangxi Province into a “tailless, less tail” mine in the middle of the 21st century.

(5) Give full play to the guiding and regulating role of various economic means

1. According to the principle of “reduction of circular economy”, through the fiscal and taxation levers, increase the economic constraints of mine tailings emissions, and reduce the tailings emissions from the source.

First, develop and improve the mineral resources recovery rate guarantee system. The mining right holder shall be required to pay a certain amount of recovery rate deposit in advance. At the end of the year, the relevant grassroots mining management agency shall check the actual recovery rate, return the deposit to the enterprise whose recovery rate is up to standard, and give appropriate rewards to fully mobilize the mining rights loop. Use the enthusiasm of tailings. Second, further improve the resource tax. It is recommended to use the progressive method in the process of collecting resource tax in the future, and link the amount of tax with the use of resources. Different tax rates are used for different resource usage. Therefore, effectively restrict the enterprises that need to use mineral resources input in large quantities, increase the economic burden of these enterprises, and force them to focus on energy conservation and efficiency in the process of development and utilization. Third, levy an environmental protection tax. Market economy entities that promote the development, utilization, pollution, and destruction of environmental resources bear the corresponding economic costs and guide them to abandon or converge on environmental damage and waste of resources. At the same time, the government can use this fund to support and encourage the market economy entities that develop circular economy.

2. According to the guiding ideology of “recycling and reuse” of circular economy, increase government input, guide social investment, and stimulate the rapid development of tailings comprehensive utilization industry.

First, further increase public finance support for the comprehensive utilization of tailings. A certain proportion of funds will be arranged for the development of policy research, technology promotion, publicity and training, and information platform construction for the comprehensive utilization of tailings, providing good information and technical services for the development of comprehensive utilization of tailings. Second, formulate financial subsidy policies that are conducive to the development of related industries. Through the government's subsidies, interest subsidies, fiscal interest subsidies, pre-tax repayment, accelerated depreciation, etc., subsidies, interest subsidies and risk sharing of tailings comprehensive utilization entities are encouraged to encourage them to develop the enthusiasm of the tailings comprehensive utilization industry. Third, improve the investment and financing system in the field of comprehensive utilization of tailings. Adhere to the principle of “who invests and who benefits”, encourage all types of investment entities with independent legal personality to invest in the comprehensive utilization of tailings in various ways. At the same time, give full play to the guiding role of government investment and government procurement on social investment, and guide various financial institutions to increase credit support for tailings comprehensive utilization projects, and establish and improve relevant financing systems and credit guarantee systems. In addition, for major projects, relevant departments should give priority to approval or filing, include provincial key project plans, give priority to direct investment and loan guarantees, and give priority to supporting the production of water, electricity and land.

3. Actively adjust the price relationship between the original resource products and the renewable resources products.

Study and improve the price formation mechanism of natural mineral resources and artificial mineral resources, and standardize the scientific distribution of production costs and industrial profits in different stages of development and utilization. Through the price difference between the two and the price policy of water and electricity, we will give better play to the role of market mechanisms in regulating the comprehensive interests of tailings.