How "Zero-Carbon" Heating Is Realized
——Investigation of Nuclear Energy Heating in Haiyang City, Shandong Province, Reporter Wang Jinhu
Recently, the topic of nuclear heating has been very hot.
On November 9th, nuclear heating was the first to achieve “city coverage” in Haiyang, Shandong, and nuclear heating gradually entered the public eye.
Immediately afterwards, on December 3, the first nuclear heating project in southern my country-Zhejiang Haiyan Nuclear Power Heating Demonstration Project (Phase I) was officially put into operation.
As one of the ways to achieve clean heating, how are nuclear heating and its advantages realized?
is it safe?
Is heating expensive?
What role can it play in environmental protection?
"This winter, my home has been powered by nuclear energy. The temperature is stable, and the price is cheaper than before." In the Jinyang Coastal Garden District of Haiyang City, Shandong Province, the thermometer of the resident Jiang Suqin's house shows that the room temperature is about 25 degrees Celsius, and the 120 square meter home is warm. Intimate.
During the Mengdong season, all parts of Shandong entered the heating season one after another.
At present, coal-fired heating is still the choice in many places.
However, Haiyang City, located on the coast of Shandong, has achieved nuclear heating a step ahead, becoming the country's first "zero-carbon" heating city.
Haiyang uses nuclear power to keep residents warm through the winter without worrying about coal supply and environmental pollution.
I look forward to it from unheard of
In winter, time is also much quieter.
Walking in the Haiyang tourist resort, thousands of miles of blue sky, white clouds drifting lightly, the sound of waves from far and near, seagulls from time to time, screaming beautifully...It is different from the "gray" sky in the heating season in the imagination , The clean and clear environment here makes people feel refreshed.
Located in the Yasha Village of Haiyang Tourist Resort, the home of Diao Wenping is warm as spring. The thermometer on the locker at the entrance of the house shows that the indoor temperature is 26 degrees Celsius, while the local minimum temperature in Haiyang as forecasted by the meteorological department that day is a bit. number.
Diao Wenping told reporters that since nuclear heating was officially started on November 9 this year, the room temperature in his home has been maintained at 267 degrees Celsius no matter how the outdoor temperature changes. Not only is the heating effect very stable, it is even higher than the boiler heating in the past. When the temperature is three or four degrees Celsius, "it is basically enough to wear short sleeves at home now, and long sleeves will feel hot, but I didn't expect the effect to be so good."
He praised the heating effect of his own home again and again.
Even though Diao Wenping is full of praise for nuclear heating, when he first heard that the heating source of the district would be changed from coal to nuclear power, he and his neighbors were also worried and puzzled.
“Before boiler heating, the room temperature can reach 22 degrees Celsius.” He recalled, because residents had never been exposed to nuclear heating, whether the heating temperature would be affected was the issue that the residents were most worried about at the beginning.
Now, this question clearly has an answer.
Residents' attitude towards nuclear heating has gradually changed from what was initially unheard of to very much looking forward to it.
Diao Wenping said: "In the early stage, the government department sent us the'understand paper' and arranged staff to answer questions. We know that nuclear heating is cleaner and more environmentally friendly. It is the future development direction. We can become the first batch of beneficiaries. very happy."
As an important practice to explore the comprehensive utilization of nuclear energy and help promote the achievement of carbon reduction goals, nuclear heating does not destroy the blue sky and white clouds, but also keeps residents warm through the winter.
It can be said that this time Haiyang took the lead in successfully achieving the "city-wide coverage" of nuclear energy heating, which is of demonstrative significance and has taken a solid step for larger-scale clean heating in the future.
The heating principle is like "self-heating small hot pot"
The primary prerequisite for achieving full coverage of nuclear heating is to ensure safety. From design and demonstration to pipeline construction, and even in all aspects of nuclear heating, Haiyang has always used science and technology to advance in an orderly manner, and will try first when there is no existing domestic experience to refer to. .
“Nuclear energy heating requires multiple barriers to isolate users and nuclear power units. During the heat exchange process, only heat is transferred without direct contact with the medium.” At Shandong Haiyang Nuclear Power Plant, part of the steam generated from nuclear power generators is extracted as a heat source. , The high-temperature water is exchanged through the heat exchanger in the factory, and then the multi-stage heat exchange through the pipe network arrives at the user terminal.
Technicians often use Internet celebrity food "self-heating small hot pot" to explain the working principle of nuclear energy heating. "The self-heating small hot pot we usually eat has a heating layer underneath, and a food layer on top, which is physically isolated and used as a thermal conductive material underneath. The inedible part only serves as a heating function and will not come into contact with the ingredients on it."
Technicians told reporters that in this way, before the hot water at the first heat exchange station of the nuclear power plant leaves the factory, the on-line monitoring and isolation device will also be tested, and the pressure difference design between the circuits will ensure the safety of heating.
Overcoming the "first kilometer" of nuclear energy heating safety, how to smoothly transport high-temperature and strong high-temperature water to the heat exchange station of the heating power company after passing through the heat exchanger of the nuclear power plant is a test of the municipal first-level pipe network. "Drainage" ability.
In an above-ground heating pipe network area located on the Dongcun River Bridge, Haixiang Middle Road, Haiyang City, the reporter saw that compared to traditional pipelines, the newly renovated pipelines that carry high-temperature water for nuclear energy heating are obviously much stronger.
Xin Zhangbo, deputy general manager of Haifa Water Group, who is responsible for the transformation of the supporting pipeline network in Haiyang City, told reporters that to support nuclear heating to cover the whole city of Haiyang means that the pipeline network will have to face greater flow and pressure. load.
To this end, they implemented a dual-line all-customized "renewal and upgrade" for the city's 46-kilometer single-line supporting pipe network from outside the nuclear power plant to various thermal power companies.
For example, the diameter of the pipe increased to 1 meter and the wall thickness of the pipe increased to 1.2 cm, nearly twice the previous.
The insulation layer used to be manually operated on site, but now it is directly integrated and prefabricated in the factory.
These technical improvements have greatly improved the pressure-bearing and thermal insulation capabilities of the pipe network, effectively reduced heat loss, and ensured the heating effect.
According to preliminary predictions, the heat loss of Haiyang nuclear heating will be 8% to 9% this year, and the entire heating season is expected to be less than 10%, which is already considerable for the long-distance pipeline network.
Not only has the piping hardware materials been upgraded, but the local pipeline network for transporting nuclear energy, heating and hot water is also intelligent for the first time.
Xin Zhangbo said: "Our pipe network is equipped with a temperature sensing device. Once there is a pipeline leak, an alarm signal will be automatically sent to the main control room as soon as possible to ensure timely and effective disposal."
100,000 tons of coal can be saved during the heating season
As early as August 2018, as the operator of the Haiyang Nuclear Power Plant, Shandong Nuclear Power initiated research on the nuclear power extraction and heating project, and successfully realized nuclear power heating in the Haiyang Nuclear Power production office.
Since then, Shandong Nuclear Power invited a team composed of “big coffee-level” experts such as China Nuclear Energy Industry Association, Tsinghua University, and General Electric Power Planning and Design Institute to report on the feasibility study of the long-distance and large-scale external heating project of the Haiyang Nuclear Power Project. After review, the technical plan was unanimously approved by experts.
In May 2019, the first batch of 700,000 square meters heating projects launched by Haiyang Nuclear Power Plant officially landed and entered the full implementation stage.
On July 10, 2019, the first phase of the 700,000 square meter project of Haiyang nuclear power heating was officially started. On September 30, 2019, the construction of the first nuclear power heating and heat exchange station and the laying of the 15-kilometer main network were completed.
During the heating season from 2019 to 2020, a total of 7,757 users in Haiyang’s Lingang, tourist resort and nuclear power industrial park 700,000 square meters have used nuclear energy for heating.
As the first commercial nuclear energy heating project in China, the project was named the "National Energy Nuclear Energy Heating Commercial Demonstration Project" by the National Energy Administration.
As the second phase of the 4.5 million square meter nuclear heating project was put into use on November 9 this year, Haiyang’s entire urban area nuclear heating model was officially launched. Haiyang has realized the transformation from traditional high-energy-consuming coal-fired heating to nuclear clean heating. Seamless switching".
"The second phase of the 4.5 million square meter nuclear energy heating project has significant advantages in improving energy efficiency and reducing carbon emissions. It has important demonstration significance for ensuring clean heating in the north, promoting carbon neutrality, and improving the regional ecological environment." Shandong Nuclear Power Said Wu Fang, secretary of the party committee and chairman of the company.
According to estimates, nuclear heating has replaced 12 coal-fired boilers in Haiyang, reducing electricity consumption by 9 million kilowatt-hours per heating season, saving 100,000 tons of coal, reducing carbon dioxide by 180,000 tons, sulfur dioxide by 1,188 tons, and nitrogen oxide by 1,123. Tons and heat are 1.3 million GJ, which is equivalent to planting 1,000 hectares of broad-leaved forest, which will effectively improve the atmospheric environment and marine ecological environment of Haiyang City during the heating season.
From burning coal to adopting nuclear energy, clean energy not only provides users with a better heating experience, but also promotes the transformation and upgrading of traditional thermal power companies.
In the view of Zhao Xin, chairman of Haiyang Haiyuan Energy Co., Ltd., with the realization of full coverage of nuclear heating in Haiyang, the company’s "dividend period" has just begun.
"For example, in 2019, we dismantled the 65-ton boiler room and converted it into the first heat exchange station of the thermal power company for nuclear heating. In the short term, the company needs to bear the cost of the renovation, but in the long run, it will be of great help to the company’s operation. "He told reporters that in the past for heating in winter, the colder the weather, the failure rate of desulfurization, boilers and other equipment will increase significantly. Because it is almost normal for enterprise staff to work overtime to repair faulty equipment, they often work until late at night, which not only worsens it. This also affects the production cost of the enterprise and also affects the heat experience of users.
After the use of nuclear energy for heating, the original boilers and environmental protection equipment are no longer used. The boiler room that used to require 9 people in groups of 3 shifts has become an unattended heat exchange station, requiring only regular inspections.
In this way, it not only saves electricity costs, maintenance costs, environmental protection expenditures and labor costs, but also effectively reduces enterprise production costs.
Taking a heating season as an example, Haiyang Haiyuan Energy Co., Ltd. can save about 3 million yuan in environmental protection, electricity and labor costs.
At the same time, Shandong Nuclear Power Corporation has not only improved the thermal efficiency of the units through the implementation of nuclear energy heating projects, but also made room for profits for residents.
After the start of the whole area heating in Haiyang City, the Haiyang Municipal Party Committee and the Haiyang Municipal Government adhered to the principle of “no increase in residential heating prices, no increase in government financial burdens, no damage to the interests of heating power companies, contributions to the operation of nuclear power companies, and great improvement in ecological and environmental benefits” Promoting the construction of nuclear energy heating projects, the heating fee has been reduced by 1 yuan per square meter compared with previous years, from the original 22 yuan per square meter to 21 yuan per square meter, making it cleaner, more economical, and more economical. Comfortable nuclear heating.
Trans-regional heating is on the agenda
In just three years, the Haiyang Nuclear Power Heating Project has completed the process from concept to design planning, implementation, and improvement.
Wang Naiyan, an academician of the Chinese Academy of Sciences, said that nuclear heating is a green and clean energy without carbon dioxide and sulfur dioxide emissions. For heating provinces, it is of great significance to replace coal with clean energy.
The Shandong Provincial Energy Bureau gave the conclusion of “clean, safe, stable and efficient” for Haiyang nuclear energy heating, and the project was demonstrated and promoted nationwide by the National Development and Reform Commission and the National Energy Administration.
In the "14th Five-Year Plan for Energy Development in Shandong Province" issued in August this year, it is proposed to implement active and orderly development and utilization of nuclear energy.
The plan calls for speeding up nuclear energy heating, building a national energy nuclear heating commercial demonstration project in an all-round way, realizing “full coverage” of 4.5 million square meters of nuclear heating in Haiyang, and building the country’s first “zero-carbon” heating city; actively promote Haiyang nuclear power Trans-regional heating to Yantai City, Qingdao Jimo and other places.
Haiyang has completed the “full coverage” of nuclear energy heating ahead of schedule, and the promotion of Haiyang Nuclear Power’s cross-regional heating of Yantai City, Qingdao Jimo and other places has also been put on the agenda.
In September of this year, the Shandong Provincial Government issued the "Implementation of the "Six Stability" and "Six Guarantees" to promote high-quality development policy list (fourth batch), which requires the integration of thermal market resources in the Jiaodong Peninsula and the preferential use of nuclear heating in areas where conditions permit. By the end of 2021, Qingdao, Yantai, and Weihai will incorporate nuclear heating into their urban heating plans.
According to relevant experts from Shandong Nuclear Power, long-distance heating needs to consider issues such as heat loss, engineering costs, material selection, and stable operation of large pipeline networks. Currently, Shandong Nuclear Power is carrying out related scientific research and research, exploration and practice of water-heat coupling.
In the future, with the in-depth development of scientific research, we will further improve efficiency and reduce costs through design optimization, application of new technologies, and selection of new materials.
Regarding the timetable for nuclear heating in the three places, heating and pipe network companies said, “This depends not only on the construction of nuclear heat sources, but also on the overall heating planning of different cities. Cross-regional heating also involves municipal planning, pipe network laying, and A series of problems such as the connection of heat and enterprises, cost accounting, etc., although these problems are not technical problems, they may be more time-consuming than overcoming technical problems."
At present, the 30 million square meters heating research project of "Nuanhe No. 1" is progressing smoothly. It is planned to start construction in 2022 and put into production in 2023.
By then, the project can cover a radius of 130 kilometers and reach the main urban areas of Yantai and Qingdao.
The future heating project of 200 million square meters is also under planning, and subsequent heating projects with a larger heating range will be gradually carried out, which will replace the heating in the main urban areas of Qingdao and Yantai with a larger area.
The reporter learned during an interview in Haiyang that in the heating season last year, the relevant person in charge of the Qingdao Housing and Construction Department had specifically visited Haiyang to investigate and connect with the issue of nuclear heating. In order to solve the problem of inter-regional nuclear heating, the cities have moved around.
——Investigation on nuclear heating in Haiyang City, Shandong
——Investigation on nuclear heating in Haiyang City, Shandong