China has a rich titanium resource and titanium dioxide industrial development has unique conditions. Titanium dioxide is a white pigment that is widely used in coatings, plastics, and papermaking industries. However, for a long time, most of the titanium dioxide industry in China has adopted the sulfuric acid method, which has low product quality, single species, and serious environmental pollution. In the world, the chlorination process has high product quality, high degree of automation, and large scale, and can realize the recycling of chlorine gas. The “three wastes†produced are only one-tenth of the sulfuric acid method and are easy to control. Gradually replace the sulfuric acid method to become the mainstream technology for titanium dioxide production. However, the advanced nature of the chlorination process can only be demonstrated when more than 90% of high grade raw materials are used.
The Dongying Dupont project site is located 25 kilometers further to the north. It is the largest estuary delta nature reserve in the country, the Yellow River Delta wetland. The Yellow River enters the sea and has a good ecological environment. The birds in the Northeast Inland and the Western Pacific must migrate as Habitat. Because of the chlorination process used in this project and the titanium raw material containing radioactivity may have a greater impact on the environment. DuPont said in its environmental assessment report that DuPont’s titanium dioxide plant in Mississippi, USA is currently the lowest cost, most technologically advanced plant in the world, while the Dongying project uses the same technology. This statement was recognized by some experts in China.
In November 2007, after two environmental impact assessments, the former State Environmental Protection Administration approved the construction of the project. It is expected that after the project is put into production, Dongying City, Shandong Province will increase revenue by 500 million yuan annually. At present, the series of procedures including the environmental assessment, land allocation and bank loans of the Dupont Dongying Project have all been approved and have not yet commenced.
Experts have questioned whether DuPont Dongying Project is "high energy-consuming and heavy-polluting"
However, some experts questioned the advanced nature of the project's process. Sun Yuanzhi, a researcher at the Institute of Process Engineering of the Chinese Academy of Sciences and former member of the chlorination titanium dioxide research team of the National Ministry of Chemical Industry, pointed out that information about the project obtained by relevant departments is not comprehensive, and DuPont Dongying Titanium Dioxide Project plans to use 60% of low-grade ore raw materials. It will cause the loss of the advanced nature of the chlorination process, and even cause more serious pollution than the sulfuric acid method. Specifically, there are three major hidden dangers in the project:
Consume more energy. The low-grade ore raw material contains a large amount of impurities, and when combined with chlorine gas, a large amount of chlorides are generated. The chlorides absorbed by these chlorides cannot be recycled and thus cause a great deal of waste of chlorine raw materials. DuPont's project report estimates that it needs to consume 160,000 tons of chlorine per year. According to calculations, if more than 90% of raw materials are used, only 200,000 tons of titanium dioxide will need to use 4-5 million tons of chlorine.
Chlorine gas production is a high-energy-consuming industry. The production of 1 ton of chlorine requires approximately 10,000 kilowatts of electricity, and the production of chlorine will produce a large quantity of by-product sodium hydroxide, which is currently in serious excess conditions. DuPont's production process using low-grade raw materials will consume 11-12 million tons of chlorine per year, ie 11-12 billion kWh. China is a country dominated by coal-fired electricity. It is not known how much coal is required for the 11-12 billion kWh of electricity and how much greenhouse gas carbon dioxide is produced after the coal is burned.
The Dupont Group stated that the project purchased chlorine instead of producing it on its own. However, Sun Yuanzhi believes that this is merely transferring a large amount of energy consumption to the environmental costs outside the company.
More carbon dioxide emissions. The production process of using 60% of the low-grade raw materials must increase the use of large amounts of petroleum coke in the production process (a large amount of waste residue in low-grade raw materials will occupy carbon in the reaction). DuPont estimates that it will consume approximately 301 kilograms of petroleum coke to produce one tonne of titanium dioxide, which is approximately 2.8 times the use of 90% high-grade raw materials. The substantial increase in the use of petroleum coke will increase the amount of carbon dioxide emitted from its production by 11 to 130,000 tons.
Emission of highly toxic gases such as carbonyl sulfide, hydrogen sulfide, and phosgene. The large-scale use of petroleum coke will inevitably lead to the production of highly toxic gases such as carbonyl sulfide, hydrogen sulfide, and phosgene. DuPont estimates that the production of sulphide is approximately 609 mg/m3 in the EIA outline, far exceeding the industry standard of 10 mg/m3. For hydrogen sulfide and phosgene emissions, DuPont has no forecast data at all.
The production process using low-grade ore raw materials will inevitably produce a large amount of chloride residue. At present, there is no clearer method for neutralizing waste slag as a building material reuse. DuPont proposed deep well perfusion as a solution. However, 1.06 million tons of strong acid waste liquid with a pH of 2 is poured into the ground every year, which does not meet the idea of ​​cleaner production.
DuPont uses its own advanced technology as an excuse to adopt a low-grade raw material production process in China. It is an act that ignores the environmental costs of China. For any industrial project, whether its technology is advanced or not, whether internationally or domestically, its evaluation criteria are the same, that is, the lowest consumption of raw materials to produce the largest number of products, product quality is good, resulting in the "three wastes" Minimal and harmless, scaled, and highly automated.
It can be seen that 60% of the low-grade raw materials used in the Dupont Dongying Titanium Dioxide Project increase the annual consumption of chlorine by 11-12 million tons, the petroleum coke consumption by 38,700 tons, and the chlorinated waste acid by 1.66 million tons. With 70,000 tons, carbon dioxide emissions have increased by 11 to 130,000 tons, all of which have greatly reduced the advanced nature of its technology. The claim that it is "the world's most advanced technology" is not valid.
According to “Southern Weekend†report, Liu Changhe, the former vice president of Jinzhou Ferroalloy Co., Ltd., the only domestic chlorination process at the moment, participated in the first environmental impact assessment of the Dupont Dongying project on November 2, 2006. He found that DuPont Group only proposed that the chlorination process used in the Dongying project was more advanced than the sulfuric acid process used by domestic manufacturers, but avoided the defects in the raw materials used in the Dongying project. He asked DuPont to add it. However, Liu Changhe was not invited to participate in the EIA review meeting on July 5, 2007.
Liu Changhe believes that the consumption of high-risk chemical substances such as chlorine, low-grade titanium raw material is twice the high grade, resulting in four times the chloride; Li Yidong, chief engineer of Jiangxi Tianguang company has higher data: More than 10 times; and there is no mention in DuPont's supplementary materials. The more chlorine that is consumed, the more chlorinated residues will be generated. The radioactive materials “Tungsten†and “Uranium†in the low-grade titanium raw materials are more, and the radioactive waste residue is bound to be more.
In this regard, Dr. Gu Xuqing, a project manager of DuPont Titanium Technologies, has his own statement: “Most of the high-grade mines are derived from low-grade ore smelting, and this process consumes more electricity, water, and other energy sources.†Therefore, the use of medium and low grades Mineral raw materials are more energy-efficient and environmentally friendly.
Compared with domestic titanium dioxide manufacturers, DuPont provides data with a low energy consumption of 30% and solid waste at a lower level, which will promote the upgrading of domestic industries and reduce the overall impact on the environment. An expert once said at the EIA: "I would rather introduce DuPont and not domestic polluters."
Mr. Keith, a U.S.-Canadian Union Steel Union expert, points out: “Using high grade titanium slag and rutile, costing 1,000 U.S. dollars per 2000 pounds, and low-grade ilmenite used in the DuPont chlorination process are only 200 U.S. dollars per 2000 pounds. The law will not bring chlorine pollution, but the level of chlorine pollution in other U.S. titanium dioxide plants using chlorination is also less than that of DuPont's chlorine pollution."
The report of the General Administration of the European Union's Joint Research Center shows that the chlorination process and the sulfuric acid process have hidden dangers in different aspects of the environment, and not who is more environmentally friendly. Chlorination can save energy and reduce waste water, but its waste is more toxic than sulfuric acid.
Expert question 2: Whether the waste is poured into a well 3000 meters above the ground is safe
The DuPont Group plans to inject the waste generated by the company into a well 3000 meters above the ground in order to avoid contamination.
Because there is no such experience in China, the national environmental authority requires that this method of deep well infusion be used as a demonstration project for the treatment of chemical industry waste in China. To this end, the DuPont Group spent $20 million in 2005 to drill a test well.
In this regard, Liu Changhe pointed out: When the waste liquid is poured into the ground of 2000-3000 meters, it will be infiltrated between the gravel layers of the rock. However, after the pollution occurs, it is difficult to deal with it. The hazardous waste pollution, especially radioactive pollution, can only be allowed to spread. . A domestic geologist also believes that only the oil field can meet the geological conditions required by this method, and not every oil field will do: not to mention 24 chlorination plants worldwide, currently only DuPont in Mississippi, USA The titanium dioxide plant (Delislle) uses this method. What is the significance of the demonstration? As for deep well perfusion, the research in this field in our country is still blank. At present, some Internet users in Dongying who have learned about the project have begun posting on the Internet calling for a boycott of the DuPont project. To this end, Liu Changhe suggested: Further in-depth investigation and process evaluation of the Dupont Dongying project, a comprehensive assessment of the advantages and disadvantages of deep-well infusion technology, and listen to public opinions in all directions.
Gu Xuqing said that ferric chloride and other wastes were infused into deep wells according to strict procedures. They are very safe. The spread after 10,000 years has not yet exceeded three kilometers. Meets EPA standards. In fact, there are no groundwater resources within tens of kilometers of Dongying. This is also a unique DuPont technology. Other manufacturers cannot use this technology because they do not master this process and do not have the geological conditions for safe underground infusion.
The two geologists who participated in the environmental evaluation of the project also affirmed the technology for waste disposal of deep wells. Xue Xiaoqun, professor of the Department of Hydrogeology at the Department of Earth Sciences, Nanjing University, pointed out that the isolation layer of the injection well is brine with much higher salt content than drinking water and cannot be used for drinking. In case of a leak in the injection well, it can also be obtained through the isolation layer. buffer. This is also the reason why the former State Environmental Protection Administration listed the project as a demonstration project.
Lu Huafu, a structural geologist at Nanjing University, confirmed that there is no fault in the geological area of ​​the Dongying area and can meet the US Environmental Protection Agency's requirement of “no transfer for 10,000 yearsâ€. At present, 89% of hazardous waste in the United States is buried deep in Class I deep wells. The United States Environmental Protection Agency also concluded in 1994 that deep wells are safer than landfills, waste cans, and incinerators.
Deep-hole infusion technology is still blank in China. At present, it lacks relevant legal restrictions and lacks strict supervision of related technical personnel. This is another aspect that experts worry about.
Lessons Learned: The DuPont Taiwan Titanium Dioxide Project Was Opposed
In 1985, Taiwan’s “United Daily†reported that DuPont plans to invest 6.4 billion Taiwan dollars in a titanium dioxide plant in the Lubin Industrial Zone, Lugang Town, Changhua County, located on the coast of Taiwan. Using the same process and raw materials as the Dongying project—a low-grade mine with a titanium dioxide content of 60%—the scrap is discarded to the deep sea. The news immediately triggered a fierce reaction from the people. Local residents live in fisheries and fear that waste water treatment will lead to increased seawater pollution. Subsequently, the local people, environmental groups, experts, and university students jointly set off a famous environmental protection campaign in the history of Taiwan.
After two years of struggle, DuPont was forced to cancel the Lukang investment plan on March 12, 1987, reviewing the entire operation process and introducing advanced technology, so it regained the trust of the island’s experts and continued to work with local residents. After two years of communication, they finally set up a factory in Guanyin Industrial Park, Taoyuan, which is far from the coast. The factory uses a high-quality titanium material containing 90% titanium dioxide, which is treated and buried in the ground slag yard.
Liu Changhe is deeply puzzled by this: Since it is DuPont's unique and advanced technology, why did you use 90% of the high-grade minerals when setting up factories in Taiwan for the second time?
According to the "Global Titanium Dioxide Industry" published by Canadian titanium dioxide industry consultancy TZMI, DuPont uses low-grade titanium raw materials in four of the world's six titanium dioxide plants. However, with the demand for environmental protection and increased production capacity, the titanium raw materials grades of the two companies have exceeded 80%. Only two factories (Mississippi and Mexico, respectively) are still using low-grade titanium raw materials in whole or in part, accounting for 16.96% of the total production capacity of the chlorination process.
The data provided by the China Titanium Dioxide Industry Annual Conference Proceedings 2007 shows that the total annual production capacity of titanium dioxide in China was 1.27 million tons, but the total demand was only 1 million to 1.2 million tons. There will be 2 million tons of projects to be launched in the next two to three years. It is far greater than the demand. Experts believe that the process adopted by the Dupont Dongying Plant is "a process route that consumes the most resources and produces the greatest pollution in the chlorination process."
According to Guo Zhenglong, secretary general of Titanium Dioxide Industry Association, there are chlorination and sulfuric acid technologies for titanium dioxide. Although China has adopted a relatively backward sulfuric acid method, a company has independently developed and adopted the chlorination method, as well as several factories. It will also be launched. Chlorination is not a blank. For such high-pollution, high-energy-consuming industries, the titanium dioxide industry associations consider that there are many problems in the Dupont Dongying project, both in terms of environmental protection and industrial development.
Based on the specific process information provided by industry experts, the annual meeting gathered opinions from the council members and formed "Several Opinions on DuPont's 200,000-ton/year Titanium Chloride Project for Chlorination" and submitted it to the National Development and Reform Commission. It is hoped that relevant government departments will exercise utmost care in the approval of such major projects, and will be able to introduce the most advanced technologies into China under certain conditions. The Chinese government must maintain the independent innovation achievements of the domestic titanium dioxide industry for 40 years, scientifically develop and make rational use of China’s abundant titanium resources, and enable the Chinese titanium dioxide industry to truly implement energy conservation and emission reduction targets and achieve sustainable development.
Yue Yihua, head of the Greenpeace pollution prevention project, believes that: First, companies should stop using any toxic substances, such as chloride, from the source of production. In addition, in the waste disposal process, even if buried deep underground, it is impossible to truly guarantee its safety, and there is still a huge potential danger. The waste disposal method for deep wells is completely contrary to the idea of ​​clean production.
Regardless of DuPont's claim that its method of deep well infusion is advanced and safe, it is, after all, just a passive end treatment of toxic waste. When a large amount of toxic waste is buried in the ground and there are long-term hidden dangers to the environment, in the short term, DuPont has avoided the responsibility of minimizing the use of toxic substances and reducing the generation of toxic waste in the process of product design and production. In a developing country, billions of dollars are invested in new projects, and the adoption of a process that does not comply with the concept of modern clean production is an irresponsible and transfer of pollution. Second, DuPont's emissions from the three titanium dioxide plants in the United States ranked first, second and seventh in the United States.
Dioxin is a colorless, odorless and highly toxic, hard-to-degrade material. Dioxins are 100 times more toxic than potassium cyanide, and they are known as “drugs of the century†and are persistent organic pollutants prohibited by the Stockholm Convention. one. The DuPont Mississippi Titanium Dioxide Plant has caused high levels of dioxin in the surrounding environment due to many years of production. It has triggered more than 2,000 civil lawsuits against DuPont by the surrounding people and was finally decided by the local court to Dupont to compensate one person suffering from bone marrow cancer. The fishermen have 14 million U.S. dollars.
In the United States, according to the "Emergency Planning and Public Access to Information Act", DuPont factories have the obligation to publicize the release of toxic substances to the public. Although DuPont stated that its corporate emissions of dioxins are all low-risk and controllable, the Tennessee government, environmental officials, and the public in which the company is located have expressed unacceptable responsibility for concealing the truth.
Similarly, the emissions of dioxin from the Dupont Dongying project also appeared only in the EIA report and no public announcement was made.
This really makes people have great doubts about DuPont's sincerity in protecting the Chinese environment.
He pointed out that in order to prevent DuPont from introducing advanced technology, it actually transferred its projects that were under great pressure in the home country to developing countries, and used China’s relatively cheap electricity, coal, labor, and environmental costs, and did not pollute factories. It is necessary to urge the NDRC to revisit the Dupont Dongying project carefully before making approvals to seek profits. Consult the opinions of more experts and ask DuPont to abandon the production process of low-grade raw materials and plan how to save energy and reduce pollutants. Emissions measures are made public to the public.
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