From October 29, 2018 to November 2, 2018, the China Town Heating Association organized a delegation to Japan to conduct comprehensive pipe gallery and heating technology exchanges, covering the Japanese heating technology and policies. During the visit, the following units and Equipment and facilities:

◆ Japan Hanshin Expressway Technology Research Co., Ltd.

◆ Osaka Prefecture Kishiwada Civil Engineering Office

◆ Japan Heat Supply Business Association

◆ Sapporo City Hall, Sapporo Energy Supply, and other local heating companies

◆ Osaka Rinku New Town Integrated Pipe Gallery, Tokyo Roppongi New Town heating facility, Sapporo train station underground heating facility, snow melting trough cooling facility, etc.

The Association hopes to strengthen communication with the Japanese side in the future and build a cooperation platform for the heating industry in China and Japan.



Learning and communication

(I) Communication with the Japan Heat Supply Business Association

The purpose of the establishment of the Japan Heat Supply Business Association is to promote the healthy development of the heat supply business and the stable supply of energy by conducting investigations, research, and popularization activities related to the heat supply business based on social requirements. The effective use of this has contributed to the development of the Japanese economy and the improvement of people's cultural life. The Japan Heat Supply Industry Association has a total of 81 formal member units, 31 sponsored member units, an area of 132, a heating area of 3.8 million square meters, a capital of 800 million yen, and 19 employees.


Organization chart of Japan Heat Supply Business Association


(2) Heating (Cold) Technology in Japanese Cities

Japan's current heating development has the following characteristics:

1. Japan's central heating (cold) systems are mostly small-scale and are mostly used for business facilities such as office buildings. The proportion of residential buildings is relatively small, but the proportion of residential buildings is also increasing rapidly in recent years;

2. Japan's regional centralized heating (cold) development speed is rapid, and the supply model is gradually diversifying;

3. Japan's heating (cold) system pays more attention to energy saving and environmental protection. While ensuring heating, it must also take into account the characteristics of beautiful cities, prevention of public hazards, and urban disaster prevention, especially to resist the impact of earthquake disasters.


Similar to the haze problems facing China now, in the 1960s and 1970s, the use of large amounts of traditional fossil fuels also deteriorated the air environment in Japan. Therefore, in order to achieve efficient use of energy, global environmental protection, and low carbon For urban construction and other purposes, diversified forms of heating have been widely promoted in Japan. These diverse forms of heating can be divided into the following categories:

1.Big volume heat storage pump system

The system uses cheap electricity at night to store energy in thermal storage tanks and provides energy during the day. The heat pump can run at full load, so as to achieve the purpose of energy saving and consumption reduction.

2. Waste heat recovery of cogeneration system

Combined heat and power systems use clean natural gas or other fuels to provide electricity while providing heat. The recovered waste heat can be used as a heat source for district central heating.

3. Utilization of waste heat in cities

District heating systems in cities can use the heat generated by factories, substations and subways in the city, otherwise they will be wasted. The generation of this heat is mainly the hot gas exhausted from the work of these facilities. It can save energy and reduce waste heat.

4.Using waste energy

Use waste energy to generate heat, that is, waste heat generated by the combustion and power generation of solid waste, RDF (garbage-derived fuel), renewable oil, and biomass (such as waste wood chips). This is not only conducive to energy conservation, but also to the management of municipal solid waste.

5.Using thermal energy brought by temperature difference

This type of heating method mainly uses the temperature difference between water temperature and air temperature, because compared with air temperature, seawater, river water, urban sewage, groundwater and other water are warm in winter and cool in summer, and the temperature is stable all year round. Therefore, different cities make use of these resources according to their own characteristics.

6.Other methods

Renewable energy, such as solar energy, geothermal energy, etc.



(3) Construction of Comprehensive Pipe Gallery

Overview of Japan's Comprehensive Pipe Gallery

Japan's comprehensive pipe gallery is divided into three types: electric wire pipe gallery, supply pipe gallery, and trunk integrated pipe gallery.

Supply gallery

[Objective] Reduce the number of excavations

[Target] gas, water, sewage

[Location] Trunk and sidewalk


The picture shows an example of Japan's supply corridor

Current Status of Japanese Pipe Gallery

The National Road Office under the Ministry of Land, Infrastructure, Transport and Tourism of Japan is responsible for the construction and management of the city's "underground comprehensive corridor" under the main arterial roads in each region. In addition to the National Highway Office, the Local Construction Bureau also undertakes the construction and management of the "underground comprehensive pipe gallery" under the road.


At present, Japan has built underground comprehensive corridors with a total length of more than 2,000 kilometers in nearly 80 cities including Tokyo, Osaka, Nagoya, Yokohama, and Fukuoka, which has played an important role in the modernization and scientific construction of Japanese cities. (The table below shows the buried corridor of the National Highway in Tokyo)



Underground pipe gallery pipeline layout




Japan's district heating is mainly in the form of combined heat and power, but it does not rely solely on natural gas. Take the heating system in the downtown area of Sapporo as an example. It is operated by Hokkaido Heat Supply Co., Ltd. This system provides high-temperature hot water of 170 ° C to 190 ° C for the urban area of Sapporo. , Not based on building area), is Japan's largest heating system, which was completed in 2009. After the transformation, the main fuel is wooden biomass, natural gas as auxiliary and backup fuel. Through technical treatment, the use of wooden biomass fuels has greatly reduced carbon emissions. According to local environmental protection departments, after the use of this biomass fuel technology in 2009, the carbon emissions were 30% of the original emissions. The reason for choosing biomass fuel is to reduce the dependence on single energy source. Secondly, there is a rich wood processing industry in the region. The waste wood fuel is cheap. In addition, the burned biomass burning ash is used in road construction materials. It can be said that three uses have been achieved.





Gains and suggestions

(1) Japanese urban heating (cold) technology-diversified forms to help clean heating

Although in terms of the popularity of combined heat and power, Japan is not comparable to the Nordic countries such as Denmark and Finland. But Japan's overall climatic conditions from south to north are very similar to China. Under the general situation that the country protects the environment and reduces carbon emissions, its multiple forms of heating are worthy of reference for our country.

(II) Construction of Comprehensive Pipe Gallery——Scientific planning, high standard construction, and perfect operation management

The construction of pipe corridors in Japan, depending on the scale, takes about five to six years from planning to completion, and requires a lot of demonstration.

The construction of urban underground comprehensive corridors must be considered according to a hundred-year plan. At the design level, various factors should be considered. The technical regulations required for design and construction (including various design, construction, and acceptance standards, etc.) are to ensure urban underground comprehensive corridors Strong support for construction. Therefore, while the national and local government departments formulate relevant construction standards and building codes, enterprises must also formulate corresponding standards according to the characteristics of their own industries in order to provide support for high-standard construction.

The repair, maintenance and renewal of the urban underground comprehensive corridor is also an important part of the construction of the urban underground comprehensive corridor. Japan ’s urban underground integrated corridors have a very comprehensive operation and management system. Usually, the specialized underground comprehensive corridor management department is responsible for overall management. At the same time, special management companies and pipeline laying units are commissioned to jointly manage according to different areas of responsibility, but The detailed rules and regulations of management must be clear at the planning stage of the construction.


Experience

Through this exchange and study in Japan, although the study time was short, it was full of gains. Established a relationship with the Japan Heat Supply Business Association, learned the planning, investment, design, construction, operation and management experience of Japan's comprehensive pipeline corridor, and exchanged with field heating companies in Japan to visit Japan's cold regions. The future development and utilization of thermal technology and unused energy have a deeper understanding. Japan's advanced technology and management in the field of heating has opened up everyone's horizons. Its concept of environmental protection and energy conservation has penetrated into every detail and is worthy of our learning and reference.






The exchange and study in Japan this time, although the time is short, but the gains are considerable. Not only did I have a certain understanding of the Japanese integrated pipe gallery and diversified heating systems, but also I was amazed by the Japanese people's truth-seeking and meticulous work, and this pursuit is derived from a serious attitude towards everything. Behind this high-standard, standardized management is the pursuit of excellence, which embodies environmentally-friendly, safe, rigorous, scientific and refined management.

"Stones from other hills, can learn". Through this exchange and learning, we better draw on the development experience of the heating industry in neighbouring countries, spurring us to continue to improve, improve and surpass.