Low Cost Hydrogen Production Platform

Timothy M. Aaron, Jerome T. Jankowiak

关键词: DESIGN;    ECONOMICS;    FABRICATION;    HEAT EXCHANGERS;    HYDROGEN;    HYDROGEN PRODUCTION;    NATURAL GAS;    OPTIMIZATION;    PRODUCTION;    RISK ASSESSMENT;    STEAM;    STEAM GENERATION;    TESTING;    WATER TREATMENT;   

DOI  :  10.2172/966044
RP-ID  :  None
PID  :  OSTI ID: 966044
Others  :  TRN: US201001%%580

学科分类：再生能源与代替技术

美国|英语

来源: SciTech Connect

【 摘 要 】

A technology and design evaluation was carried out for the development of a turnkey hydrogen production system in the range of 2.4 - 12 kg/h of hydrogen. The design is based on existing SMR technology and existing chemical processes and technologies to meet the design objectives. Consequently, the system design consists of a steam methane reformer, PSA system for hydrogen purification, natural gas compression, steam generation and all components and heat exchangers required for the production of hydrogen. The focus of the program is on packaging, system integration and an overall step change in the cost of capital required for the production of hydrogen at small scale. To assist in this effort, subcontractors were brought in to evaluate the design concepts and to assist in meeting the overall goals of the program. Praxair supplied the overall system and process design and the subcontractors were used to evaluate the components and system from a manufacturing and overall design optimization viewpoint. Design for manufacturing and assembly (DFMA) techniques, computer models and laboratory/full-scale testing of components were utilized to optimize the design during all phases of the design development. Early in the program evaluation, a review of existing Praxair hydrogen facilities showed that over 50% of the installed cost of a SMR based hydrogen plant is associated with the high temperature components (reformer, shift, steam generation, and various high temperature heat exchange). The main effort of the initial phase of the program was to develop an integrated high temperature component for these related functions. Initially, six independent concepts were developed and the processes were modeled to determine overall feasibility. The six concepts were eventually narrowed down to the highest potential concept. A US patent was awarded in February 2009 for the Praxair integrated high temperature component design. A risk analysis of the high temperature component was conducted to identify any potential design deficiency related to the concept. The analysis showed that no fundamental design flaw existed with the concept, but additional simulations and prototypes would be required to verify the design prior to fabricating a production unit. These identified risks were addressed in detail during Phase II of the development program. Along with the models of the high temperature components, a detailed process and 3D design model of the remainder of system, including PSA, compression, controls, water treatment and instrumentation was developed and evaluated. Also, in Phase II of the program, laboratory/fullscale testing of the high temperature components was completed and stable operation/control of the system was verified. The overall design specifications and test results were then used to develop accurate hydrogen costs for the optimized system. Praxair continued development and testing of the system beyond the Phase II funding provided by the DOE through the end of 2008. This additional testing is not documented in this report, but did provide significant additional data for development of a prototype system as detailed in the Phase III proposal. The estimated hydrogen product costs were developed (2007 basis) for the 4.8 kg/h system at production rates of 1, 5, 10, 100 and 1,000 units built per year. With the low cost SMR approach, the product hydrogen costs for the 4.8 kg/h units at 50 units produced per year were approximately $3.02 per kg. With increasing the volume production to 1,000 units per year, the hydrogen costs are reduced by about 12% to $2.67 per kg. The cost reduction of only 12% is a result of significant design and fabrication efficiencies being realized in all levels of production runs through utilizing the DFMA principles. A simplified and easily manufactured design does not require large production volumes to show significant cost benefits. These costs represent a significant improvement and a new benchmark in the cost to produce small volume on-site hydrogen using existing process technologies. The cost models assume a natural gas cost of $5/MMBtu (HHV). Praxair has, in Phases I and II of this program, shown that significant improvements in cost, plant layout, system integration and overall system optimization are achievable. Phase III of the program, submitted in January 2007, was to focus on demonstrating both the technical feasibility and economic viability of the design developed in Phases I and II through a full-scale prototype design, construction, installation, analysis and operation at a hydrogen fueling station. Due to funding limitations, Phase III of the program was not approved by the DOE.