Wearing a "mask" to prevent PM2.5 on boilers using low-temperature SCR denitrification catalysts

Publishdate:2015-12-22 Views:15

Starting from the 7th, Beijing has once again entered a "haze mode", accompanied by the launch of a red warning for heavy pollution. It is currently the heating season, and coal-fired and natural gas heating boilers in the city emit a large amount of pollutants, which are directly or indirectly converted into the familiar and disliked fine particulate matter PM2.5 in recent years. According to previous tracing, coal-fired emissions contribute nearly 1/4 of Beijing's PM2.5. If this part of PM2.5 can be "solved", it will undoubtedly be of great significance to "Beijing Blue".

The reporter learned from Beijing University of Technology that Professors He Hong and Li Jian from the School of Environment and Energy Engineering at the university, along with their research team, have devoted themselves to research for many years and developed a comprehensive honeycomb type low-temperature SCR denitrification catalyst. This catalyst can significantly reduce the nitrogen oxide emissions from coal-fired and gas boilers, effectively preventing the conversion of nitrogen oxides to PM2.5. Assembling block by block honeycomb catalyst materials is equivalent to putting a PM2.5 resistant "mask" on the boiler.

Experts from different fields collaborate to do "side jobs"

In 1998, Beijing experienced a total of 76 smog days, with a stable type of weather that was not conducive to the diffusion of atmospheric pollutants occurring at a frequency of 40.4%, and nitrogen oxides increasing by 14% compared to the previous year. In response to the severe air pollution situation, the Beijing Municipal Government took 18 emergency measures at the end of that year to control coal smoke pollution, motor vehicle exhaust pollution, and dust pollution.

In the autumn of that year, He Hong officially came to Beijing University of Technology to engage in teaching and research in the field of catalytic chemistry. "As a native of Beijing, I have a great understanding of how the air quality in Beijing has deteriorated. With the rapid development of the economy, chimneys have emerged, and pollutants such as sulfur dioxide and nitrogen oxides are directly discharged into the atmosphere." He Hong said that from 1993 to 1996, while pursuing a doctoral degree at Hong Kong Baptist University, he knew that the West has strict control over nitrogen oxide emissions, The process of purifying nitrogen oxides through a series of technologies is called "denitrification", but looking around the mainland, the "denitrification" process has only just begun in recent years.

Looking for materials on the periodic table of chemical elements

In 2004, the two of them led a research team to start making basic formulas. Compared to other scientific research projects in terms of project initiation, approval, defense, and award evaluation, the projects of He Hong and Li Jian were completely "covert operations" in the early years. There is no project proposal, no research endpoint, no research funding, and even the school director is unaware. "We just want to try hard and see how much lower the temperature of the catalyst material can be made," Li Jian said. At that time, they both had a plan, and once they succeeded, they would directly turn the laboratory results into industrial products that can be applied. "To be honest, we won't do any fancy research."

The division of labor between the two is clear. He Hong leads the students to be responsible for the research and preparation of catalyst materials, while Li Jian leads the students to be responsible for the molding and engineering application of catalyst modules. Finding suitable low-temperature catalyst materials is not an easy task. He Hong said that they searched for samples of the periodic table, including sodium, magnesium, aluminum, iron, zinc, copper, etc., and constantly compared and tested them. Except for a few radioactive elements, they tried almost all the elements on the periodic table.

"At that time, we had our own research topics, and the teaching and research tasks were also heavy, but we quietly persevered in this research." He Hong said, his laboratory was on the fifth floor, and Li Jian's laboratory was upstairs. Every day, the two of them would run in tandem upstairs and downstairs. "This was a great way to lose weight at that time," he laughed.

Such a large project, involving specific product preparation, is unimaginable without funding. He Hong admitted that conducting research at that time could only save more and more. If it really didn't work, the two of them would "scrape" the surplus funds from other scientific research projects or use some equipment left over from other projects. "Although it seems very non-standard now, it was indeed a last resort at the time," He Hong said.

In 2008, two teams made breakthrough progress in their research, and a material called vanadium molybdenum titanium greatly improved the low-temperature adaptability of honeycomb catalysts. "In the laboratory, this material can guarantee catalytic performance even at 160 ℃. At first, we couldn't believe it and it took us a long time to repeatedly verify," He Hong said.

Pollutants are reduced to nitrogen and water

Significant breakthroughs have been made in material research and development, but products are still far away. Li Jian told reporters that the powder produced in the laboratory is the catalyst material, which needs to be processed through multiple processes such as extrusion and forming to become the final product. The processing technology in this process is crucial to ensure the final effect of the material.

Hard work pays off for those who are willing. They found a company in Wuqing, Tianjin to conduct industrial experiments, and then found a factory in Zibo, Shandong willing to process catalyst materials. So almost every week, the two of them had to rush from Beijing to Shandong. "At that time, the railway to Zibo was not as convenient as it is now, so we had to drive there," He Hong said. After unremitting efforts, they processed catalyst materials with specifications such as 30 pores and 40 pores, "The 40 hole material is very rare internationally due to its high processing difficulty. It has a better effect on purifying natural gas boilers' emissions of nitrogen oxides and is suitable for pollution reduction in major cities such as Beijing."

Recently, the reporter saw samples of these two catalyst materials in the experimental building of Beijing University of Technology. At first glance, they are rectangular shapes, with small pores densely distributed in the middle. "The cross-sectional length of the rectangular shape is 15 centimeters, and 40 pores mean that there are 40 small pores in this section of the material, which has 40 flue gas channels." Li Jian explained that after adding ammonia to pollutants such as nitrogen dioxide and nitrogen oxide emitted from the boiler, they undergo reduction reactions and become nitrogen and water through these catalyst materials, "Nitrogen is the main component of the Earth's atmosphere, and water samples are beneficial and harmless to organisms," said Li Jian.

In Li Jian's laboratory, the reporter witnessed the miraculous effect of this honeycomb material. After passing through the material, the concentration of nitrogen oxides in the flue gas was miraculously reduced to 6.83 milligrams per cubic meter, "far below the current standard limit for boiler emissions in Beijing." Li Jian said.

Expected to help Beijing thermal power enterprises reduce emissions

With good technology and products, it is natural to push them to the market, which is the goal of He Hong and Li Jianchu. This technology has been successfully transformed through Beijing's Jia Technology Co., Ltd., but encountered many difficulties in its initial promotion. "People are used to foreign products and don't trust our technology," He Hong said. One time, he brought materials to a company in Wuhan, Hubei, and the factory thought he was just a salesperson, hastily passing the time. "They didn't even give a glass of water to drink," He Hong said. But later, as their products became well-known in the industry, even the local environmental protection bureau director would accompany them throughout the journey, hoping to use this new technology.

Li Jian told reporters that the overall honeycomb type low-temperature SCR denitrification catalyst has broad application prospects. A coal-fired boiler with a capacity of 20 tons can effectively purify nitrogen oxides by combining 10 cubic meters of catalyst materials and installing them into a denitrification reactor. This catalyst material has been put into use in multiple heating communities in Beijing, and they are still in talks with the Beijing Southwest Thermal Power Center, which is responsible for important power supply missions. Advanced catalyst materials are expected to be put into use in Beijing's environmentally friendly and advanced thermal power center.

In the process of promoting applications, their products also encountered difficulties in driving out good coins with inferior ones. Some domestic manufacturers have launched catalyst materials that claim to also achieve denitrification functions, stirring up the market at low prices. "They only charge 10000 yuan per cubic meter, which is simply impossible and the cost is not enough. Unless unknown materials are added, it is meaningless to actually reduce emissions." He Hong said that they will also increase technological research and reduce material costs in the future, and also hope that relevant departments can increase supervision, "This is also a protection for our scientific research enthusiasm"


Starting from the 7th, Beijing has once again entered a "haze mode", accompanied by the launch of a red warning for heavy pollution. It is currently the heating season, and coal-fired and natural gas heating boilers in the city emit a large amount of pollutants, which are directly or indirectly converted into the familiar and disliked fine particulate matter PM2.5 in recent years. According to previous tracing, coal-fired emissions contribute nearly 1/4 of Beijing's PM2.5. If this part of PM2.5 can be "solved", it will undoubtedly be of great significance to "Beijing Blue".

The reporter learned from Beijing University of Technology that Professors He Hong and Li Jian from the School of Environment and Energy Engineering at the university, along with their research team, have devoted themselves to research for many years and developed a comprehensive honeycomb type low-temperature SCR denitrification catalyst. This catalyst can significantly reduce the nitrogen oxide emissions from coal-fired and gas boilers, effectively preventing the conversion of nitrogen oxides to PM2.5. Assembling block by block honeycomb catalyst materials is equivalent to putting a PM2.5 resistant "mask" on the boiler.

Experts from different fields collaborate to do "side jobs"

In 1998, Beijing experienced a total of 76 smog days, with a stable type of weather that was not conducive to the diffusion of atmospheric pollutants occurring at a frequency of 40.4%, and nitrogen oxides increasing by 14% compared to the previous year. In response to the severe air pollution situation, the Beijing Municipal Government took 18 emergency measures at the end of that year to control coal smoke pollution, motor vehicle exhaust pollution, and dust pollution.

In the autumn of that year, He Hong officially came to Beijing University of Technology to engage in teaching and research in the field of catalytic chemistry. "As a native of Beijing, I have a great understanding of how the air quality in Beijing has deteriorated. With the rapid development of the economy, chimneys have emerged, and pollutants such as sulfur dioxide and nitrogen oxides are directly discharged into the atmosphere." He Hong said that from 1993 to 1996, while pursuing a doctoral degree at Hong Kong Baptist University, he knew that the West has strict control over nitrogen oxide emissions, The process of purifying nitrogen oxides through a series of technologies is called "denitrification", but looking around the mainland, the "denitrification" process has only just begun in recent years.

Looking for materials on the periodic table of chemical elements

In 2004, the two of them led a research team to start making basic formulas. Compared to other scientific research projects in terms of project initiation, approval, defense, and award evaluation, the projects of He Hong and Li Jian were completely "covert operations" in the early years. There is no project proposal, no research endpoint, no research funding, and even the school director is unaware. "We just want to try hard and see how much lower the temperature of the catalyst material can be made," Li Jian said. At that time, they both had a plan, and once they succeeded, they would directly turn the laboratory results into industrial products that can be applied. "To be honest, we won't do any fancy research."

The division of labor between the two is clear. He Hong leads the students to be responsible for the research and preparation of catalyst materials, while Li Jian leads the students to be responsible for the molding and engineering application of catalyst modules. Finding suitable low-temperature catalyst materials is not an easy task. He Hong said that they searched for samples of the periodic table, including sodium, magnesium, aluminum, iron, zinc, copper, etc., and constantly compared and tested them. Except for a few radioactive elements, they tried almost all the elements on the periodic table.

"At that time, we had our own research topics, and the teaching and research tasks were also heavy, but we quietly persevered in this research." He Hong said, his laboratory was on the fifth floor, and Li Jian's laboratory was upstairs. Every day, the two of them would run in tandem upstairs and downstairs. "This was a great way to lose weight at that time," he laughed.

Such a large project, involving specific product preparation, is unimaginable without funding. He Hong admitted that conducting research at that time could only save more and more. If it really didn't work, the two of them would "scrape" the surplus funds from other scientific research projects or use some equipment left over from other projects. "Although it seems very non-standard now, it was indeed a last resort at the time," He Hong said.

In 2008, two teams made breakthrough progress in their research, and a material called vanadium molybdenum titanium greatly improved the low-temperature adaptability of honeycomb catalysts. "In the laboratory, this material can guarantee catalytic performance even at 160 ℃. At first, we couldn't believe it and it took us a long time to repeatedly verify," He Hong said.

Pollutants are reduced to nitrogen and water

Significant breakthroughs have been made in material research and development, but products are still far away. Li Jian told reporters that the powder produced in the laboratory is the catalyst material, which needs to be processed through multiple processes such as extrusion and forming to become the final product. The processing technology in this process is crucial to ensure the final effect of the material.

Hard work pays off for those who are willing. They found a company in Wuqing, Tianjin to conduct industrial experiments, and then found a factory in Zibo, Shandong willing to process catalyst materials. So almost every week, the two of them had to rush from Beijing to Shandong. "At that time, the railway to Zibo was not as convenient as it is now, so we had to drive there," He Hong said. After unremitting efforts, they processed catalyst materials with specifications such as 30 pores and 40 pores, "The 40 hole material is very rare internationally due to its high processing difficulty. It has a better effect on purifying natural gas boilers' emissions of nitrogen oxides and is suitable for pollution reduction in major cities such as Beijing."

Recently, the reporter saw samples of these two catalyst materials in the experimental building of Beijing University of Technology. At first glance, they are rectangular shapes, with small pores densely distributed in the middle. "The cross-sectional length of the rectangular shape is 15 centimeters, and 40 pores mean that there are 40 small pores in this section of the material, which has 40 flue gas channels." Li Jian explained that after adding ammonia to pollutants such as nitrogen dioxide and nitrogen oxide emitted from the boiler, they undergo reduction reactions and become nitrogen and water through these catalyst materials, "Nitrogen is the main component of the Earth's atmosphere, and water samples are beneficial and harmless to organisms," said Li Jian.

In Li Jian's laboratory, the reporter witnessed the miraculous effect of this honeycomb material. After passing through the material, the concentration of nitrogen oxides in the flue gas was miraculously reduced to 6.83 milligrams per cubic meter, "far below the current standard limit for boiler emissions in Beijing." Li Jian said.

Expected to help Beijing thermal power enterprises reduce emissions

With good technology and products, it is natural to push them to the market, which is the goal of He Hong and Li Jianchu. This technology has been successfully transformed through Beijing's Jia Technology Co., Ltd., but encountered many difficulties in its initial promotion. "People are used to foreign products and don't trust our technology," He Hong said. One time, he brought materials to a company in Wuhan, Hubei, and the factory thought he was just a salesperson, hastily passing the time. "They didn't even give a glass of water to drink," He Hong said. But later, as their products became well-known in the industry, even the local environmental protection bureau director would accompany them throughout the journey, hoping to use this new technology.

Li Jian told reporters that the overall honeycomb type low-temperature SCR denitrification catalyst has broad application prospects. A coal-fired boiler with a capacity of 20 tons can effectively purify nitrogen oxides by combining 10 cubic meters of catalyst materials and installing them into a denitrification reactor. This catalyst material has been put into use in multiple heating communities in Beijing, and they are still in talks with the Beijing Southwest Thermal Power Center, which is responsible for important power supply missions. Advanced catalyst materials are expected to be put into use in Beijing's environmentally friendly and advanced thermal power center.

In the process of promoting applications, their products also encountered difficulties in driving out good coins with inferior ones. Some domestic manufacturers have launched catalyst materials that claim to also achieve denitrification functions, stirring up the market at low prices. "They only charge 10000 yuan per cubic meter, which is simply impossible and the cost is not enough. Unless unknown materials are added, it is meaningless to actually reduce emissions." He Hong said that they will also increase technological research and reduce material costs in the future, and also hope that relevant departments can increase supervision, "This is also a protection for our scientific research enthusiasm"