从“气”到“氢”的一字之变 四川资阳打造成渝氢走廊氢源配送中心From 'Gas' to 'Hydrogen': Ziyang, Sichuan Builds a Hydrogen Supply Distribution Center for the Chongqing-Chengdu Hydrogen Corridor

Lin Feng Town in Anyue County, Ziyang City, Sichuan Province, where pipelines of the Ziyang Branch of China National Petroleum Corporation's Southwest Oil & Gas Field Natural Gas Purification Plant roar day and night. The natural gas extracted from underground has its hydrogen sulfide removed here, and the clean gas is delivered to millions of households. In the past, the removed hydrogen sulfide was highly toxic waste that had to be disposed of at a cost; today, a new process is about to turn it into high-purity hydrogen to power cars and locomotives.

This is the starting point of Ziyang's hydrogen energy story. China's 15th Five-Year Plan has listed hydrogen energy as a key future industry direction, and the Chengdu-Chongqing hydrogen corridor is one of the country's five pilot zones. This corridor has been operating for over four years, promoting 1,577 hydrogen fuel cell vehicles and building 34 hydrogen refueling stations, but it has always lacked a stable, low-cost local hydrogen source — most hydrogen is transported from hundreds of kilometers away by tube trailer, costing thirty to forty yuan per kilogram at station. Located at the geographic center of the corridor, Ziyang is working on this conversion from “gas” to “hydrogen,” which differs by only one Chinese radical in characters, but represents an industrial shift.

The confidence of Ziyang primarily lies beneath its feet. The Anyue gas field has confirmed reserves of 1.45 trillion cubic meters, accounting for 7.4% of the national total and 33.3% of the provincial total, with conventional natural gas reserves ranking first in the province. It has been included in the national 100-billion-cubic-meter-level production capacity bases and China’s "Gas Daqing" strategic layout. As of now, Anyue has built 350 exploration and development wells and 17 gas gathering stations.

What’s even more special is that the natural gas here has a high sulfur content—the raw gas contains 15 to 30 grams of hydrogen sulfide per cubic meter. The extracted gas cannot be burned directly; it must go through an advanced purification plant: desulfurization, dehydration, sulfur recovery, and tail gas treatment, removing the hydrogen sulfide so that clean gas can be transmitted externally. In the past, this hydrogen sulfide was a hot potato, highly toxic and costly to handle; today, it has become Ziyang’s most unique "raw material asset" for developing hydrogen energy.

"Turning waste into hydrogen, both hydrogen and sulfur can be used, and both by-products are very valuable," said Zhou Jun, head of the comprehensive working group of the Hydrogen Energy Industry Task Force in Ziyang High-tech Zone. Using off-site electrocatalytic technology, hydrogen sulfide can be directly decomposed into high-purity hydrogen and sulfur, significantly reducing raw material costs. The Ziyang branch plant acts as a 'converter' for this resource—one end is connected to the underground gas field, purifying sulfur-containing natural gas into clean gas for export; the other end is connected to a future hydrogen production project, where the hydrogen sulfide 'stripped' daily is exactly the 'fuel' for hydrogen production. Currently, both units of the plant are fully operational, processing 4 billion cubic meters of natural gas annually.

Another advantage of Ziyang is its location. It is the only prefecture-level city in Sichuan directly connected to both Chengdu and Chongqing, forming a 'dual-core' area; 85% of the traffic between Chengdu and Chongqing passes through here, and the three main transport routes of the Chengdu-Chongqing hydrogen corridor intersect here. The hydrogen refueling network along the corridor is becoming denser—Chongqing Expressway Group plans to build or upgrade 25 hydrogen refueling stations by 2028. Since hydrogen transportation is costly and shorter distances are more economical, Ziyang, located at the geographic center, is naturally suitable as a 'distribution center' for hydrogen sources. Lei Xianzhang, director of the Tianfu New Energy Research Institute, put it more plainly, 'Hydrogen can be distributed from Ziyang, east to Chongqing, west to Chengdu.'

The key to turning 'gas' into 'hydrogen' is how to efficiently and cost-effectively produce hydrogen. Ziyang's answer is to take a two-pronged approach. The first approach is electrocatalytic hydrogen production from hydrogen sulfide off-gas, which can rely on by-product hydrogen sulfide from the Ziyang branch plant, directly decomposing the waste into high-purity hydrogen and sulfur, with a planned annual capacity of about 9,000 tons and a purity of up to 99.999%. No other company in China has yet achieved large-scale industrial application of this route. The second approach is photovoltaic water electrolysis for hydrogen production, aiming for an annual output of over 600 tons of green hydrogen. At the same time, biomass hydrogen production by Beijing Zhongdi Smart Energy is also in Ziyang's scope, using straw as raw material, costing 17 to 19 yuan per kilogram, with containerized equipment that can produce and refuel hydrogen on-site.

Ziyang's only hydrogen refueling station currently started operation in April 2024, with a daily hydrogen refueling capacity of 500 kilograms and a listed price of 52 yuan per kilogram. "Hydrogen prices need to be below 30 yuan to have economic value," said Li Caixin, General Manager of Ziyang Sinopec High-New Energy Co., Ltd. At present, it mainly refuels a few local hydrogen buses and vehicles passing through from the Chengdu-Chongqing route. "Only when the price comes down will more passing vehicles choose this station." Ziyang's 15th Five-Year Plan for Industrial and Information Development clearly states the intention to actively integrate into the Sichuan-Chongqing urban cluster hydrogen comprehensive application pilot and the Chengdu-Chongqing 'hydrogen corridor' construction, accelerate the industrial demonstration application of hydrogen production from hydrogen sulfide off-site electro-catalysis, and strengthen the local low-cost hydrogen supply capacity.

A city with a hydrogen source, if there are no local companies that can make use of hydrogen, is just a 'hydrogen mine,' not a 'hydrogen industry.' Ziyang's manufacturing foundation is not something that appeared overnight—CRRC Ziyang Locomotive, Hyundai Commercial Vehicles, and Ziyang Petroleum Steel Pipe are all local industrial assets, and now these three companies have simultaneously entered the hydrogen energy sector. CRRC Ziyang is the only fuel cell locomotive manufacturer in the province, and hydrogen-powered locomotives have already been commercially operated outside the province in Guizhou; Hyundai Commercial Vehicles has delivered over 700 hydrogen-powered light trucks, operating in Guangzhou, Sichuan-Chongqing, Xinjiang, and other places, with a total mileage of more than 25 million kilometers and an energy conversion efficiency of about 64%.

[Source: People's Daily Online - Sichuan Channel]

[Editor: Xiao Neng]