The trace of hydrogen energy application can be traced back to gasoline and natural gas. Today, hydrogen energy, as the backbone of energy transformation, plays an important role in areas that are difficult to decarbonize. For example, power, manufacturing and transportation are the main sources of carbon emissions, while hydrogen energy can reduce carbon emissions from the use end and energy storage end.
In the future, the hydrogen energy industry will be integrated with renewable energy and other low-carbon technologies, and diversified in transportation, power, industry and other fields. According to the current energy situation in China, the development of hydrogen energy is one of the important starting points to achieve the goal of double carbon.
1. Current situation of hydrogen energy transportation
The large-scale development of hydrogen energy industry is directly related to the breakthrough of hydrogen energy storage and transportation technology. Due to the particularity of current hydrogen energy and the restriction of industry technology, and the superposition of the characteristics of high density of "hydrogen" element and high transportation loss, hydrogen energy transportation forms a separate link in the hydrogen energy industry chain.
Hydrogen needs to go through the transportation link from hydrogen production to application end. The transportation mode of hydrogen varies according to its storage mode, mainly including gas transportation, liquid transportation, solid transportation and organic liquid transportation. The international hydrogen transportation modes mainly include long tube trailer gas transportation, liquid hydrogen tanker transportation and pipeline transportation.
At present, the more mature application mode in the market is gas transportation, that is, the gas is transported to the terminal by truck, long pipe trailer or pipeline. In this process, the long tube trailer will generally give 200-500 times the atmospheric pressure, while the pipeline will give 10-40 times, and the cost will be 2.02 yuan /kg and 0.3 yuan /kg respectively. In general, pipeline transportation will be safer and can adapt to longer distance transportation.
2 what are the safety risks during hydrogen storage and transportation?
In the hydrogen energy industry chain, the storage and transportation of hydrogen is the key to connect the supply end and the demand end. From the perspective of characteristics, hydrogen is relatively safer than other fuels, and it is not easy to form explosive gas mist. Therefore, the safety and reliability of hydrogen transportation can be effectively improved by establishing effective prevention and control measures during hydrogen storage and transportation and paying attention to safety problems in all links.
Safety assurance during hydrogen transportation - trailer transportation
At present, the long tube trailer is the most widely used for hydrogen storage and transportation, and there will be some risks in the process of transportation. The risks can be reduced by taking effective measures such as setting safety cylinders / pressure gauges / electrostatic conductive devices / fire extinguishing devices, setting safety thermometers, setting safety bursting discs, etc. to ensure the safety of hydrogen filling and transportation.
Safety assurance during hydrogen transportation - liquid hydrogen tank car transportation
The liquid hydrogen tank car has high transportation and storage capacity, which is suitable for medium distance transportation, but has high requirements for heat insulation of hydrogen storage containers; In addition, liquid hydrogen evaporation and ultra-low temperature liquid hydrogen leakage will occur during transportation, causing harm to human body and the environment. In this case, a pressure relief valve can be installed on the device to regulate the internal pressure of the device; In addition, with the help of intelligent inspection and monitoring technology, remote on-board monitoring equipment can be built to give early warning of safety hazards such as failure modes of new transportation equipment and personnel illegal operations, so as to realize intelligent early warning and risk traceability and troubleshooting of hydrogen energy transportation.
Safety assurance during hydrogen transportation - Pipeline hydrogen transportation
Pipeline hydrogen transportation has irreplaceable economy under large-scale and long-distance conditions. It is a priority and practical choice to solve the problem of large-scale and low-cost transportation of hydrogen energy. Through the design, construction, operation and maintenance of hydrogen energy pipeline, the pipeline involves sealing, pipeline risk assessment, regular inspection, etc., which can realize stable and reliable pipeline transmission of hydrogen energy or hydrogen doped natural gas.
3 how to avoid the safety risks of hydrogen transportation?
Based on the uniqueness of hydrogen transportation, we must be extra careful in hydrogen transportation to avoid major accidents. At the same time, relevant staff shall be equipped with portable hydrogen gas detector to timely detect whether hydrogen leaks.
First of all, a safety detection, monitoring and early warning mechanism should be established for the way of pipeline hydrogen transmission: during the pipeline construction, the management of hydrogen doped pipeline welds and nondestructive testing should be strengthened, the buried depth should be appropriately increased, and the research on risk control technologies and equipment such as adding exhaust pipes to casing pipes when crossing roads, railways and streets should be carried out. In the operation process, it is necessary to strengthen the real-time online detection of pipeline leakage and establish an early warning and emergency support system for hydrogen doped natural gas leakage.
Secondly, establish accident emergency and risk control: hydrogen energy transportation accident disposal emergency not only needs professional maintenance and repair teams, pipeline and tank car repair equipment, but also needs the assistance of social resources. In this field, it is urgent to establish a hydrogen energy transportation collaborative emergency and intelligent decision-making big data platform and corresponding key technical support.
In the whole hydrogen energy industry chain, safe and efficient transmission is an important part of the industry chain. At the present stage, based on the transportation experience of natural gas and other gases, foreign hydrogen energy operation standards and the continuous development and improvement of China's hydrogen energy industry, as well as the systematic quantitative research on the occurrence, development mode and mechanism of hydrogen accidents and prevention and control technology, China's hydrogen energy safety standardization will be more scientific, systematic and widely applicable, and promote the vigorous development of the hydrogen energy industry more efficiently.
