The construction ceramics industry is an important part of the national economy and an indispensable basic product industry to improve people's livelihood and meet the people's growing needs for a better life.
After nearly four decades of rapid development, China has become the world's largest producer and consumer of architectural ceramics. The output of architectural ceramics accounts for more than 60% of the world's total output. Consumption has ranked first in the world for many years.
While developing rapidly, the architectural ceramics industry consumes a large amount of resources and energy and generates a large amount of greenhouse gases. According to industry estimates, the building ceramics industry consumes 150 to 200 million tons of raw materials and 40 to 60 million tons of standard coal in energy each year. Direct carbon dioxide emissions range from 0.9 to 140 million tons, and indirect emissions are about 40 million tons.
The implementation of the "dual carbon" strategy has had a huge impact on the architectural ceramics industry. From the comprehensive perspectives of "dual control" of energy consumption, coal reduction, and the realization of the "double carbon" goal of environmental protection, it is necessary to optimize the energy consumption structure and support and encourage industry enterprises to achieve energy use transformation and upgrading.
The fuel used in the building ceramics industry has gone through the energy consumption process of coal (carbon), oil, coal (gas production), and natural gas (liquefied petroleum gas).
The fuels traditionally used for ceramic firing in my country are wood and coal. Since the early 1950s, generator gas has been used to bake building sanitary ceramic products in Shenyang, Tangshan and other places. In the 1950s, my country introduced atmospheric fixed-bed gasifiers from the Soviet Union. From the 1950s to the early 1980s, my country's gasifiers were mainly domestically produced atmospheric-pressure fixed-bed gasifiers [1].
With the development of my country's petroleum industry, heavy oil has gradually replaced producer gas since 1971. By the early 1980s, with the widespread application of oil-fired flame-muffled roller kilns, heavy oil became the main fuel for building ceramics. By the 1990s, due to increased requirements for environmental protection, companies that burned heavy oil later switched to burning light diesel.
In the 1980s, my country introduced two-stage gas generators from Italy, the United States, France, the United Kingdom and other countries. With the increase in usage, coal gasification technology has become increasingly mature. Open-flame roller kilns have gradually replaced muffled flame roller kilns, and have the characteristics of high efficiency, safety, and energy saving. In the 1990s, its cost was only 1/3-2/3 of the cost of fuel, and the economic benefits were obvious.Chemical technology is widely used in the ceramic industry.
In the 21st century, the country has increased its efforts in environmental protection. Since pollutants such as hydrogen sulfide, tar, and phenol water are produced during the coal-to-gas process, if not treated properly, they will seriously affect the quality of local air and water. Many local governments require coal-to-gas production for environmental and drinking water safety considerations. gas to clean natural gas. However, due to the limited supply of natural gas, by the end of 2015, the fuel for my country's building ceramics industry was still mainly coal gas.
According to the construction ceramics production capacity survey, as of 2017, natural gas accounted for 34% of the fuel used in kilns in the construction ceramics industry, and it will reach 50% in 2020.
According to data released by relevant national departments, my country's energy consumption structure will continue to be optimized in 2020, with a total consumption of 4.98 billion tons of standard coal, and the proportion of coal consumption further dropped to less than 58%, and natural gas accounted for The ratio has increased to 8.5%, and the consumption of clean energy such as water, nuclear power, wind and photovoltaics accounts for nearly 16% of total energy consumption.
The "Energy Production and Consumption Revolution Strategy" (2016-2030) proposes that from 2021 to 2030, the use of renewable energy, natural gas and nuclear energy will continue to grow, and the use of high-carbon fossil energy will decrease significantly. . Total energy consumption is controlled within 6 billion tons of standard coal, non-fossil energy accounts for about 20% of total energy consumption, and natural gas accounts for about 15%. New energy demands are mainly met by clean energy. Looking forward to 2050, total energy consumption will be basically stable, with non-fossil energy accounting for more than half.
In order to achieve the 2030 carbon peak and 2060 carbon neutrality goals, the energy consumption of the building ceramics industry needs to be transformed and upgraded to low-carbon and zero-carbon energy.
1. Before 2030, natural gas will become the main energy used by the industry, but factors such as its price and supply restrict the application of natural gas in the industry< /p>
Natural gas is a clean and low-carbon fossil energy that will play an important role in the green and low-carbon transformation of global energy. At present and in the long term in the future, my country's energy development has entered a development stage of coexistence of incremental substitution and stock substitution, promoting The green and low-carbon transformation of energy and the orderly expansion of natural gas utilization are one of the important ways to help peak energy carbon and build a clean, low-carbon, safe and efficient energy system [2].
In the next 15 years, natural gas supply and consumption will trend upward
In 2020, China's natural gas production was 192.5 billion cubic meters, a year-on-year increase of 9.8%. The growth rate of natural gas production has been faster than the growth rate of consumption for two consecutive years, and supply security capabilities have continued to improve. Natural gas imports were 140.4 billion cubic meters, a year-on-year increase of 3.6%. China's natural gas consumption was 328 billion cubic meters, an increase of approximately 22 billion cubic meters, a year-on-year increase of 6.9%, accounting for 8.4% of total primary energy consumption.
Through reasonable guidance and market construction, natural gas consumption is expected to reach 430 billion to 450 billion cubic meters in 2025, and 550 billion to 600 billion cubic meters in 2030. After that, natural gas consumption will stabilize Sustainable growth will enter a development platform period around 2040. Since then, as the substitution of electric energy and hydrogen energy has accelerated, terminal natural gas consumption has steadily declined, falling to 50 to 160 billion cubic meters in 2060 [3].
With the same calorific value, the carbon emissions of natural gas are nearly 40% lower than that of standard coal
The emission factors recommended by the National Development and Reform Commission's "Interim Measures for the Promotion and Management of Energy-Saving and Low-Carbon Technologies" are 2.64 tCO2/tce for coal and 1.63 tCO2/tce for natural gas. Using natural gas instead of coal can reduce carbon dioxide emissions by nearly 40%.
Architectural ceramic roller kilns use natural gas instead of coal to produce gas, which has energy-saving effects[4]
When the kiln uses coal gas, due to the low calorific value of coal gas, in order to obtain the same temperature in the kiln and ensure the same lateral temperature difference in the kiln, the kiln used The coal-to-gas burner is equipped with a large air-to-combustion ratio, which results in an increase in kiln exhaust and heat loss. Therefore, the combustion efficiency of coal-to-gas is lower than that of natural gas. The kiln was originallyAfter switching from coal gas to natural gas, the air coefficient of the kiln combustion process is reduced, the amount of combustion-supporting air entering the kiln is reduced, and the amount of smoke leaving the kiln is reduced, which can reduce the heat loss of the exhaust smoke and has an energy-saving effect.
There is much room for improvement in the proportion of natural gas
In 2020, the output of architectural ceramics was 8.569 billion square meters, consuming 47 million tons of standard coal. It is estimated that natural gas is about 10 billion cubic meters. Natural gas consumption accounts for 3% of national consumption and 8.1% of industrial natural gas consumption. With the further advancement of the "coal-to-gas" policy, the implementation of the "dual carbon" strategy, and the advantages of natural gas in "energy saving and carbon reduction", the proportion of natural gas in the energy consumption structure of the building ceramics industry will further increase and become the main energy source in the industry.
In 2030, assuming that natural gas accounts for 60% of the comprehensive energy consumption in the production of building ceramics, the demand for natural gas will be approximately 30 billion cubic meters, accounting for approximately 5% of the national demand. %.
Factors such as natural gas price and supply limit its application in the building ceramics industry
Natural gas prices fluctuate greatly, especially during the winter heating season, when prices rise exponentially.
Fuel costs account for more than 30% of the production costs of ceramic tiles. Ordinary ceramic tiles are very sensitive to fluctuations in natural gas prices, and meager profits can easily be offset by rising gas prices. The supply of natural gas cannot be guaranteed, and supply interruptions occur frequently, causing ceramic companies to suffer heavy losses. The above factors have led to a decrease in the willingness of ceramic companies to use natural gas. Although the "coal-to-gas" policy has been advanced in depth and has been stepped up layer by layer, and even "one size fits all", the progress of replacing coal-based gas with natural gas is still slow. Adequate supply and stable prices have become the common aspirations of ceramic companies. According to reports, LNG futures officially received project approval from the China Securities Regulatory Commission at the end of 2021 and is accelerating its listing work. The listing of natural gas futures will help form my country's natural gas benchmark price and reduce natural gas price fluctuations.
2. 2Before 2030, the available hydrogen energy cannot meet the needs of large-scale applications in the industry. It can be used in some areas with conditions.
Hydrogen energy can be divided into "gray hydrogen", "blue hydrogen" and "green hydrogen". At present, natural gas is mainly used to produce hydrogen internationally, while coal-based hydrogen production is the main method in my country. The mainstream choice of global hydrogen production technology is hydrogen production from fossil energy, mainly due to the low cost of hydrogen production from fossil energy. Among them, hydrogen production from natural gas accounts for 48% of the world due to its good cleanliness, high efficiency and relatively low cost. my country's energy structure is "rich in coal and low in gas", and the cost of hydrogen production from coal is lower than that from natural gas. Therefore, domestic hydrogen production from coal accounts for the largest share (64%), followed by industrial by-products (21%) [5].
In 2020, my country's hydrogen production was approximately 33.42 million tons, accounting for nearly one-third of the world's hydrogen production. It is the world's largest hydrogen producer. The main sources are hydrogen production from fossil energy and electrolysis. The production of hydrogen from water is less than 1%. In the field of terminal consumption, hydrogen utilization as industrial raw materials accounts for more than 99%, and hydrogen utilization as energy accounts for less than 0.1%. It is mainly utilized in the transportation sector in the form of hydrogen fuel cell vehicles [6].
It is estimated that by 2030, my country's annual hydrogen production will reach 37 million tons, and the proportion of hydrogen produced by electrolysis of water will reach about 15%. Most hydrogen is used as industrial raw materials, and the consumption as energy is 3.2 million tons, equivalent to 13 million tons of standard coal, of which about 10 million tons of standard coal are used in hydrogen fuel cell vehicles.
Before 2030, the hydrogen energy that can be used as energy in the building ceramics industry is far lower than the annual energy consumption of the industry, and cannot be widely used in the industry, and does not take into account transportation, Storage and cost issues.
However, some production areas or enterprises close to rich hydrogen resources (such as industrial by-product hydrogen) can consider using hydrogen energy as the main energy source and increase the research and development application of hydrogen energy in building ceramic products.
3. Green power and kiln electrification are the keys to the industry achieving carbon neutrality
Although natural gas is "energy-saving and carbon-reducing," it is still a fossil energy and still emits carbon emissions. After 2030, the industry's energy structure will gradually transform to zero-carbon energy. Hydrogen-doped natural gas may be a transition, and hydrogen energy, biomass energy, etc. can be used as supplements. As the electrification level of the industrial sector increases, the energy consumption of the building ceramics industry will eventually use green electricity..
According to the Greenhouse Gas Emissions Report Supplementary Data Sheet, the average emission factor for the national power grid in 2015 was 0.6101 tCO2/MWh, and this data has been used in subsequent years. In December 2021, in the latest public solicitation for "Corporate Greenhouse Gas Emission Accounting Methods and Reporting Guidelines for Power Generation Facilities (2021 Revised Edition)" (draft for comments) issued by the General Office of the Ministry of Ecology and Environment, the average emission factor of the national power grid was adjusted to The latest is 0.5839tCO2/MWh, a decrease of about 4.3%. The decline in this number reflects the rapid development of clean energy sources such as wind power and photovoltaics in my country in recent years and the continuous reduction in the average standard coal consumption of thermal power plants.
Converted based on 0.5839tCO2/MWh, the current carbon dioxide emission factor of electricity is 4.75kgCO2/kgce, and its emissions are about 1.8 times that of coal and about 2.8 times that of natural gas. Therefore, at the current stage, the higher the degree of electrification of the industry, the higher the corresponding indirect carbon dioxide emissions. When the proportion of green electricity increases to a certain level and the average emission factor of the national power grid drops below 0.2tCO2/MWh, the emissions from using electricity will be equivalent to that of natural gas with the same calorific value.
(1) The proportion of green electricity in electricity will be greatly increased
In 2020, the country's full-scale power generation was 7,626.4 billion kWh, an increase of 4.1% over the previous year, of which hydropower was 1,355.3 billion kWh, an increase of 4.1% over the previous year; thermal power was 5,177 billion kWh, an increase of 2.6% over the previous year; nuclear power 366.2 billion kWh, an increase of 5.0% over the previous year; grid-connected wind power was 466.5 billion kWh, an increase of 15.1% over the previous year; grid-connected solar power generation was 261.1 billion kWh, an increase of 16.6% over the previous year [7].
Figure 2 National full-scale power generation structure in 2020< /span>
Under the "dual carbon" goal, the requirements for low-carbon development of energy and electricity have become increasingly prominent. The installed capacity of non-fossil energy power generation will continue to grow, and the power supply structure is developing in a cleaner and lower-carbon direction. . From the perspective of power generation, non-chemicalThe proportion of fossil energy power generation will gradually increase from about 30% in 2020 to 50% in 2030, and 80%-90% in 2060[8].
Hydropower is still the main force in renewable energy generation
Hydropower is the "leader" in renewable energy generation, generating far more electricity than wind and solar power. The status of hydropower in China has been greatly improved. Coal-fired power currently ranks first in China's power generation share, and hydropower ranks second. As of the end of 2020, China's hydropower installed capacity was approximately 370 million kilowatts, accounting for approximately 19% of the country's total installed power generation capacity; power generation capacity was approximately 1,355.3 billion kilowatt hours, accounting for more than 60% of all renewable energy generation capacity. In 2020, the country's full-scale power generation installed capacity reached 2,200.58 million kilowatts, and the country's full-scale hydropower installed capacity reached 370.16 million kilowatts, accounting for 16.82% of the total installed capacity.
According to China’s long-term hydropower development plan, the installed hydropower capacity will be approximately 520 million kilowatts by 2030, and the hydropower development level will be approximately 60%. By 2060, the installed hydropower capacity will be approximately 700 million kilowatts, and the hydropower development level will be 73%.
Wind power is the third largest conventional power source
Wind power is a clean, pollution-free and sustainable form of energy utilization. After 40 years of development, wind power has developed into the third largest conventional power source in China after thermal power and hydropower, and has certain cost advantages among various types of power sources. At present, the cumulative scale of wind power grid-connected across the country has reached 282 million kilowatts, and the annual power generation is approximately 0.5 trillion kilowatt-hours. The power generation cost of onshore wind power has dropped to a level comparable to the cost of coal-fired power generation. In some areas, it is even 0.1 yuan lower than coal power per kilowatt-hour. Offshore wind power is expected to achieve grid parity around 2025 [9].
As of the end of 2020, the country’s cumulative installed wind power capacity was 281.53 million kilowatts[10], which was 225 times that of 2005, accounting for 12.8% of my country’s total installed power generation capacity. However, the proportion of wind power in my country's power structure is still very low. In 2020, the country's wind power generation reached 466.5 billion kilowatt hours, accounting for 6.1% of the country's total power generation.
According to forecasts, China's cumulative installed wind power capacity will be 445 million kilowatts in 2030 and 1.254 billion kilowatts in 2050 (approximately 4.5 times the actual cumulative installed wind power capacity in 2020); wind power generation in 2030 will be 0.84 trillion kilowatt hours , it will be 2.45 trillion kWh in 2050 (about 5 times that of 2020). China’s electricity consumption is expected to reach 8 trillion kWh in 2050 [11] (the total electricity consumption in the whole society in 2020 is 7.51 trillion kWh). This means that wind power will account for 30.6% of the electricity production structure by then.
Photovoltaic power generation is the fastest growing type of power supply
my country's photovoltaic power generation has maintained rapid growth in recent years, with the installed capacity reaching 250 million kilowatts in 2020. Encouraged by relevant policies such as "County-wide Photovoltaic Development", the development of photovoltaic power generation will further accelerate. In the future, photovoltaic power generation will be the leader in the development of non-fossil energy under the "double carbon" goal for a long time. It will maintain a strong growth momentum from now to 2060 and become the power source with the largest growth rate. It is expected that the installed capacity will reach about 550 million kilowatts and 800 million to 830 million kilowatts in 2025 and 2030 respectively, and will increase to about 2 billion kilowatts in 2060. The installed capacity of photovoltaic power generation is currently lower than that of coal power, hydropower, and wind power, and is expected to become the power source with the largest capacity between 2030 and 2035.
Nuclear power capacity will grow steadily
Nuclear power is a clean and reliable power source with a high number of utilization hours. With the large-scale development of wind power and photovoltaic power generation, it can make a greater contribution to the power balance of the system. It is an important force in achieving the "double carbon" goal and should develop nuclear power efficiently on the basis of ensuring safety. In 2020, my country's nuclear power installed capacity will be approximately 50 million kilowatts. The development of nuclear power in my country is affected by factors such as power plant site selection space and planning and construction cycle. Without the development of inland nuclear power, it is expected that the installed capacity will reach approximately 80 million, 120 million, and 230 million kilowatts in 2025, 2030, and 2050 respectively. , the installed capacity will remain stable after 2050.
(2) The electrification of energy-using equipment in the industry has become an inevitable trend
According to "China"Energy and Power Development Outlook" (2021), electric energy will gradually occupy the core position of terminal energy consumption, and the electrification rate will continue to increase. It will be about 30% in 2025, more than 50% in 2050, and is expected to reach 70% in 2060.
In the construction ceramics industry, electric energy will account for 10%-15% of comprehensive energy consumption in 2020, and there is huge room for improvement. The key to improving the electrification rate of the building ceramics industry lies in the electrification of kiln equipment. Kiln energy consumption accounts for about 60%, and the current main energy sources are coal gas and natural gas. Changing the gas-fired roller kiln to the electric-fired roller kiln has become an important way to improve the electrification rate of the industry.
(3) Electrically fired roller kilns save more energy and reduce carbon emissions than gas fired roller kilns
Traditional firing kilns in the architectural ceramics industry mainly use gas-fired roller kilns. The electric heated roller kiln is a new type of kiln currently under development. By using electric fired roller kiln technology, combustion air is not required, the flue gas volume is reduced by more than 80%, and the firing energy consumption is theoretically reduced by about 50%. Considering the utilization of waste heat from the gas-fired roller kiln, the comprehensive energy saving of the electric-fired roller kiln can reach more than 20%.
The gas-fired roller kiln is replaced by electric firing. Based on the fact that green electricity accounts for 80% of the electricity, the carbon emissions are reduced by about 85%, and the emission reduction effect is very significant.
(4) Electricity prices will be more competitive in the future
The issue that the industry is most concerned about is the supply and price of energy. Energy supply is planned uniformly by the state. In terms of energy prices, due to the non-renewable nature of fossil energy, primary energy prices are expected to continue to rise; with the advancement of green power technology and the gradual increase in its proportion, electricity prices will show a downward trend, or at least remain stable. , so compared with fossil energy, electricity prices will be more competitive. This reduces obstacles to increasing the electrification rate of the industry.
The fuel used in the building ceramics industry has gone through the processes of coal (carbon), oil, coal (gas production), and natural gas (liquefied petroleum gas). Natural gas will become the main energy source for industry development before 2030. In areas where conditions permit, hydrogen energy can also be used as an alternative. After 2030, electric mixed combustion may be a transition. With the improvement of the greenness of the power structure, the electrification of building ceramic kilns has becomeKey to carbon neutrality for the industry. Ceramic kiln equipment companies need to plan in advance and increase the research and development of electric fired roller kilns to contribute to the industry's carbon neutrality in 2060.
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[2] China Natural Gas Development Report. 2021.
[3] China Energy and Power Development Outlook. 2021.
[4] Wu Zhiliang. Technical measures for “coal-to-gas” fuel conversion in ceramic enterprises and energy conservation and environmental protection benefits. Ceramics. 2019.7
[5] 2021 Hydrogen Energy Industry Analysis Report.
[6] China Energy and Power Development Outlook 2021.
[7] China Electric Power Industry Annual Development Report 2021.
[8] China Energy and Power Development Outlook.2021.
[9] Qin Haiyan. "Local Governments Relay to Promote the Affordable Development of Offshore Wind Power in 2025". China Wind Power Network.
[10] "National Energy Administration releases national power industry statistics in 2020", National Energy Administration website.
[11] Li Ping. Liu Qiang, Wang Qia, et al. "China's Energy Prospects 2018-2050".
