Some Environmental Aspects of Hydrogen Production

Hydrocarbons (predominantly, NG) are likely to play a major role in hydrogen production in the near- to medium-term future. However, hydrocarbons significantly contribute to anthropogenic C02 emissions into the atmosphere. Spath and Mann [11] estimated that the global warming potential (GWP) of hydrogen production by the SMR process is 13.7 kg C02 (equiv.) per kg of net hydrogen produced. GWP is defined as a combination of C02, CH4, and N20 emissions expressed as C02 equivalence for a 100-year time frame. 

C02 accounts for 77.6% of the system s GWP. According to Scholz, C02 emissions from the SMR process is 0.44 Nm3 C02/Nm3 H2 [4]. Thus, a typical SMR hydrogen plant with the capacity of 1 million m3 of hydrogen per day produces over 0.4 million standard m3 of C02 per day, which is normally vented into the atmosphere. 

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