生物质热化学转化制氢技术

生物质是一种重要的可再生能源，是氢的载体，与矿物燃料相比，具有挥发分高，硫、氮含量低等优点。无论是从能源角度还是从环境角度，发展生物质制氢技术都具有重要的意义。目前有关生物质制氢方面的研究主要集中在热化学转换法和生物法，文章从热化学转换的角度，进行了几种生物质制氢路线的技术经济分析预测。     

乙醇重整制氢催化剂的国内研究进展

制氢技术是发展燃料电池的关键技术之一,而目前研究较多且具有良好应用前景的制氢技术是乙醇水蒸气重整制氢法制氢。综述了国内水蒸气重整法、部分氧化法、氧化重整法等乙醇重整制氢法的研究进展,同时综述了乙醇水蒸气重整制氢催化剂助剂、载体的研究进展。指出了在较低温度下以高转化率、低C0选择性、高氢气选择性制氢是乙醇制氢技术研究的方向。     

可再生能源制氢系统制氢电源研究

利用风电、光伏发电等可再生能源电力的制氢系统是未来制备氢能的发展方向,而制氢电源是制氢系统的核心部件.传统的基于晶闸管整流电路的制氢电源(下文简称为"晶闸管制氢电源")存在功率因数低、谐波大,延迟长等缺点.针对这一问题,本文采用PWM整流器作为制氢电源(下文简称为"PWM制氢电源"),把逆变电路中的SPWM调制和数字控...     

太阳能制氢关键技术研究

围绕太阳能制氢技术展开论述,首先,介绍太阳能制氢技术的研究现状;其次,对于太阳能制氢技术尤其是光催化制氢技术及热化学循环分解水制氢技术,分别从技术原理、关键材料、技术难点等方面进行详细的论述;最后,对太阳能制氢技术研究给出结论及建议,旨在为未来太阳能制氢技术的研发布局和产业技术突破提供参考和思路。     

制氢技术

正制氢技术日新月异。煤气化制氢虽产生大量CO_2,但因原料丰富、价格低廉,仍是规模化、低成本人工制氢的最佳途径;高炉烟道气、化工尾气等通过变压吸附(PSA)技术可低成本回收氢;太阳能制氢技术(光催化、光热解)是未来理想的制氢技术,但受制于转换效率和成本等,预计2030年前难实现规模化。电解水制氢可有效消纳风电、光伏发电等不稳定电力,以及其他富余波谷电力,因而将贯穿于氢能发展全过程,是工业氢气主要来源之一。     

炼厂制氢装置停运可行性及经济性探讨

低氢成本战略是现代炼厂的重要发展战略,优化炼厂氢资源和低氢成本管理是炼厂低氢成本战略的重要组成部分。延安石油化工厂20km~3/h(标准)制氢装置是企业汽柴油质量升级项目配套装置,正常生产状况下,制氢装置与1.2Mt/a连续重整装置所产氢气供全厂用氢装置使用。制氢装置停运前后全厂氢气、燃料气及蒸汽产耗状况表明,制氢装置停运后,重整装置所产氢气能满足全厂用氢需求,增开燃煤锅炉或调整燃煤锅炉的运行负荷均可实现全厂蒸汽的产耗平衡,通过补充液化气可以弥补燃料气出现的缺口。经测算,停运制氢装置后,一年可节约费用约4055万元,经济效益可观。制氢装置停运后,一旦重整装置出现问题,将会给生产带来一定困难,所以必须确保重整装置的安稳、长周期运行及制氢装置完好备用,以便需要开工供氢时能在较短时间内投运。     

几种生物质制氢方式的探讨

生物质资源丰富，是一种重要的可再生能源而且其自身是氢的载体；与矿物燃料相比，具有挥发分高，硫、氮含量低等优点，无论是从能源角度还是从环境角度，发展生物质制氢技术都具有重要的意义。文章论述了生物质制氢的各种方式，介绍了各自的优缺点及面临的困难，着重论述了生物质热化学转换方式制氢，并对其未来的应用前景做了一定的预测。     

制氢技术

综述了几种主要的制氢技术及其发展现状，评述了各种制氢技术的发展前景。     

风光互补与电解水制氢系统负荷的协调稳定运行

电解水制氢作为一种新型储能手段，可作为调整风光能源输出电力的绿色手段。该文以风力发电、光伏发电、电解制氢与燃料电池为研究对象，通过对风光互补发电系统与电解水制氢系统的输出输入功率进行建模仿真，协调优化控制风光电、电解槽、燃料电池以及系统负载的负荷变化要求，改善了风光发电电解水制氢系统与系统负荷之间的负荷不平衡问题，为风光互补可再生能源系统的稳定运行提供了理论依据。     

天然气裂解制氢的研究进展

综述天然气裂解制氢的研究进展,包括介绍催化裂解制氢、等离子体裂解制氢、等离子体催化制氢以及太阳能热解制氢等技术的特点及其国内外研究现状并进行比较分析,基于综述分析提出了相关研究重点。     

The Sono-Hydro-Gen process (Ultrasound induced hydrogen production): Challenges and opportunities

Producing hydrogen using ultrasonic waves offers tremendous opportunities, which could lead to a clean, affordable and reliable energy source. Introducing high-frequency ultrasonic waves to liquid water could provide an efficient way to produce efficient and clean hydrogen. This particular review makes a focus on the application of power ultrasound in hydrogen production and discusses the challenges, opportunities and future directions. This new, ultrasonic based hydrogen production technology is given the name of “Sono-Hydro-Gen”. It is well known that hydrogen can be formed from the dissociation of water molecules subjected to ultrasound via the so-called sonolysis process. Factors affecting the hydrogen production rate and the theory beyond these effects are described herein. The average hydrogen production-rate reported from the Sono-Hydro-Gen process is 0.8 μMol per minute at an acoustic intensity of 0.6 W cm⁻². This review also compares the Sono-Hydro-Gen technology with the most commonly used technologies and it is found that this technology could lead to a prosperous and secure hydrogen energy for the future. Recent numerical and experimental investigations on the hydrogen production pathways have been reviewed showing various numerical simulations for different experimental configurations. Finally, performance and efficiency criteria are discussed along with the challenges associated with the Sono-Hydro-Gen process.     

Large-vscale hydrogen production and storage technologies: Current status and future directions

Over the past years, hydrogen has been identified as the most promising carrier of clean energy. In a world that aims to replace fossil fuels to mitigate greenhouse emissions and address other environmental concerns, hydrogen generation technologies have become a main player in the energy mix. Since hydrogen is the main working medium in fuel cells and hydrogen-based energy storage systems, integrating these systems with other renewable energy systems is becoming very feasible. For example, the coupling of wind or solar systems hydrogen fuel cells as secondary energy sources is proven to enhance grid stability and secure the reliable energy supply for all times. The current demand for clean energy is unprecedented, and it seems that hydrogen can meet such demand only when produced and stored in large quantities. This paper presents an overview of the main hydrogen production and storage technologies, along with their challenges. They are presented to help identify technologies that have sufficient potential for large-scale energy applications that rely on hydrogen. Producing hydrogen from water and fossil fuels and storing it in underground formations are the best large-scale production and storage technologies. However, the local conditions of a specific region play a key role in determining the most suited production and storage methods, and there might be a need to combine multiple strategies together to allow a significant large-scale production and storage of hydrogen.     

Optimizing hydrogen production capacity and day ahead market bidding for a wind farm in Texas

Producing green hydrogen from wind energy is one potential method to mitigate curtailment. This study develops a general approach to examine the economic benefit of adding hydrogen production capacity through water electrolysis along with the fuel cell and storage facilities in a wind farm in north Texas. The study also investigates different day ahead market bidding strategies in the existence of these technologies. The results show that adding hydrogen capacity to the wind farm is profitable when hydrogen price is greater than $3.58/kg, and that the optimal day ahead market bidding strategy changes as hydrogen price changes. The results also suggest that both the addition of a fuel cell to reconvert stored hydrogen to electricity and the addition of a battery to smooth the electricity input to the electrolyzer are suboptimal for the system in the case of this study. The profit of a particular bidding scenario is most sensitive to the selling price of hydrogen, and then the input parameters of the electrolyzer. This study also provides policy implications by investigating the impact of different policy schemes on the optimal hydrogen production level.     

Adapting the French nuclear fleet to integrate variable renewable energies via the production of hydrogen: Towards massive production of low carbon hydrogen?

Producing low-carbon hydrogen at a competitive rate is becoming a new challenge with respect to efforts to reduce greenhouse gas emissions. We examine this issue in the French context, which is characterised by a high nuclear share and the target to increase variable renewables by 2050. The goal is to evaluate the extent to which excess nuclear power could contribute to producing low-carbon hydrogen.Our approach involves designing scenarios for nuclear and renewables, modelling and evaluating the potential nuclear hydrogen production volumes and costs, examining the latter through the scope of hydrogen market attractiveness and evaluating the potential of CO₂ mitigation.This article shows that as renewable shares increase, along with the hydrogen market expected growth driven by mobility uses, opportunities are created for the nuclear operator. If nuclear capacities are maintained, nuclear hydrogen production could correspond to the demand by 2030. If not, possibilities could still exist by 2050.     

Optimizing hybrid offshore wind farms for cost-competitive hydrogen production in Germany

Nearly 96% of the world's current hydrogen production comes from fossil-fuel-based sources, contributing to global greenhouse gas emissions. Hydrogen is often discussed as a critical lever in decarbonizing future power systems. Producing hydrogen using unsold offshore wind electricity may offer a low-carbon production pathway and emerging business model. This study investigates whether participating in an ancillary service market is cost competitive for offshore wind-based hydrogen production. It also determines the optimal size of a hydrogen electrolyser relative to an offshore wind farm. Two flexibility strategies for offshore wind farms are developed in this study: an optimal bidding strategy into ancillary service markets for offshore wind farms that build hydrogen production facilities and optimal sizing of Power-to-Hydrogen (PtH) facilities at wind farms. Using empirical European power market and wind generation data, the study finds that offshore-wind based hydrogen must participate in ancillary service markets to generate net positive revenues at current levels of wind generation to become cost competitive in Germany. The estimated carbon abatement cost of “green” hydrogen ranges between 187 EUR/tonCO₂e and 265 EUR/tonCO₂e. Allowing hydrogen producers to receive similar subsidies as offshore wind farms that produce only electricity could facilitate further cost reduction. Utilizing excess and intermittent offshore wind highlights one possible pathway that could achieve increasing returns on greenhouse gas emission reductions due to technological learning in hydrogen production, even under conditions where low power prices make offshore wind less competitive in the European electricity market.     

A comparative study on hydrogen production from steam-glycerol reforming: thermodynamics and experimental

A detailed comparative study on thermodynamic and experimental analyses of glycerol reforming for hydrogen production has been conducted in terms of the effects of temperature, pressure, water to glycerol feed ratio, feeding reactants to inert gas ratio and feeding gas flow rate (residence time). The thermodynamic analysis was conducted by using a non-stoichiometric methodology based on the minimisation of Gibbs free energy. And the experiments were carried out with a pilot scale set-up. The results show that the thermodynamic and experimental data agree fairly well with each other. The measured hydrogen production is slightly lower than that predicted by the thermodynamic analysis, which is mainly because the conversion of steam is incomplete. High temperature, low pressure, low feeding reactants to inert gas ratio and low gas flow rate are favourable for steam reforming of glycerol for hydrogen production. There is an optimal water to glycerol feed ratio for steam reforming of glycerol for hydrogen production which is about 9.0. The glycerol conversion is a strong function of water to glycerol ratio, whereas a weak function of other parameters over the conditions of this work. A novel adsorption enhanced reaction process incorporating water and heat recovery is proposed for further optimisation of hydrogen production from steam reforming of glycerol.     

Optimized photovoltiac system for hydrogen production

Hydrogen, which can be produced by water electrolysis, can play an important role as an alternative to conventional fuels. It is regarded as a potential future energy carrier. Photovoltaic arrays can be used in supplying the water electrolysis systems by their energy requirements. The use of photovoltaic energy in such systems is very suitable where the solar hydrogen energy systems are considered one of the cleanest hydrogen production technologies, where the hydrogen is obtained from sunlight by directly connecting the photovoltaic arrays and the hydrogen generator. This paper presents a small PV power system for hydrogen production using the photovoltaic module connected to the hydrogen electrolyzer with and without maximum power point tracker. The experimental results developed good results for hydrogen production flow rates, in the case of using maximum power point tracker with respect to the directly connected electrolyzer to the photovoltaic modules.     

A review on integrated thermochemical hydrogen production from water

Hydrogen production from water splitting is considered one of the most environmentally friendly processes for replacing fossil fuels. Among the various technologies to produce hydrogen from water splitting, thermochemical cycles using chemical reagents have the advantage of scale up compared to other specific facilities or geological conditions required. According to thermochemical processes using chemical redox reactions, 2-, 3-, 4-step thermochemical water splitting cycles can generate hydrogen more efficiently due to reducing temperatures. Increasing the number of cycles or steps of thermochemical hydrogen production could reduce the required maximum temperature of the facility. In addition, recently developed hybrid thermochemical processes combined with electricity or solar energy have been studied on a large scale because of the reduced cost of hydrogen production. Additionally, hybrid thermochemical water splitting combined with renewable energy can result in not only reducing the cost, but also increasing hydrogen production efficiency in terms of energy. As for a green energy, hydrogen production from water splitting using sustainable and renewable energy is significant to protect biological environment and human health. Additionally, hybrid thermochemical water splitting is conducive to large scale hydrogen production. This paper reviews the multi-step and highly developed hybrid thermochemical technologies to produce hydrogen from water splitting based on recently published literature to understand current research achievements.     

Assessing techno-economic uncertainties in nuclear power-to-X processes: The case of nuclear hydrogen production via water electrolysis

Nuclear assisted low carbon hydrogen production by water electrolysis represents a potential application of nuclear cogeneration towards deep decarbonization of several fossil fuel-dependent industrial sectors. This work builds a probabilistic techno-commercial model of a water electrolysis plant coupled to an existing nuclear reactor for base load operations. The objective is to perform discounted cash flow (DCF) calculations for levelized nuclear hydrogen production cost under input parameter uncertainty. The probability distributions of inputs are used with the Monte Carlo-Latin Hypercube (MC-LH) sampling technique to generate 10⁵ input scenarios and corresponding distribution of the levelized or life cycle hydrogen production cost instead of deterministic point values. Based on current techno-economic conditions, the levelized production costs of electrolytic hydrogen using electricity from large water-cooled nuclear reactors are determined to be US $ 12.205 ± 1.342, 8.384 ± 1.148 and 6.385 ± 1.051/kg H₂ respectively at rated alkaline water electrolyser capacities of 1.25 MW(e), 2.5 MW(e) and 5 MW(e). The corresponding values for PEM water electrolysers are US $ 13.162 ± 1.356, 8.891 ± 1.141 and 6.663 ± 1.057/kg H₂. The potential for flexible nuclear reactor operation and management of power demand uncertainties through nuclear hydrogen cogeneration is also examined through a case study.