Design‐based risk assessment on an ammonia‐derived urban hydrogen refueling station

Abstract

The increase in the number of hydrogen (H 2 ) fuel cell vehicles necessitates the swift installation of requisite infrastructure such as H 2 refueling stations (HRSs). However, the use and storage of high-pressure gaseous H 2 in conventional HRSs limits inventory and poses safety risks. In this regard, ammonia (NH 3 ) is a potential solution as an H 2 carrier with high storage capacity that can be stored as a liquid. However, NH 3 is toxic and accidental exposure to it is fatal for humans. Therefore, this study aims to develop a process and safety design for HRSs using NH 3 as the H 2 carrier. The operation of ammoniaderived H 2 refueling stations comprises dehydrogenation and refueling processes, for which quantitative risk assessment was performed based on process design data. Consequently, it was determined that NH 3 leakage from the storage tank was the dominant accident scenario and that the associated risk exceeded the acceptable risk criteria. Therefore, we proposed a risk mitigation strategy that involves installing a dike to guarantee safe design and operation.

Quantitative Risk Assessment of a Liquid Organic Hydrogen Carriers based Hydrogen Refueling Station

“…3.1 The QRA procedure QRA evaluates the risk associated with equipment by combining the consequences of an accident occurring with tis frequency of occurrence [17,18,21,22,42,43]. Figure 3 depicts the QRA procedure.…”

“…Bae et al [22] designed an AHRS process through simulation and obtained design data for conducting a QRA. Since the release of ammonia from the storage tank would cause signi cant damage to the surrounding community using a dike as a mitigation measure was provided to limit the spread of ammonia gas to prevent the formation of a pool and to reduce the maximum dispersion distance.…”

Simulation Study on Combustion Performance of Ammonia-Hydrogen Fuel Engines

“…Moreover, existing refueling stations can meet the demand for liquid ammonia refueling [13,14]. However, ammonia gas exhibits lower chemical reactivity, difficulty in ignition, and slow combustion rate, so it is necessary to blend high-reactivity fuels to display their superior performance [15,16].…”

Thermocatalytic Ammonia Decomposition – Status and Current Research Demands for a Carbon‐Free Hydrogen Fuel Technology

“…Due to the mentioned potential health hazards of ammonia, Lee et al. published a comprehensive risk assessment for this application [27] . Meanwhile, Chatterjee et al.…”

“…Due to the mentioned potential health hazards of ammonia, Lee et al published a comprehensive risk assessment for this application. [27] Meanwhile, Chatterjee et al give a more critical analysis on the use of ammonia-derived hydrogen. [28] The main drawbacks, they report, are considered to be the high energy demands for the decomposition reaction and subsequent hydrogen purification, which lower the overall energy efficiency.…”