NOVELTY - Reducing carbon dioxide emissions of petroleum refinery/petrochemical/hydrogen plant involves: a) feeding hydrocarbon feedstocks and steam to steam reformer unit, to create synthetic gas stream; b) shifting synthetic gas stream to create shifted synthetic gas stream; c) capturing carbon dioxide from the stream through carbon dioxide absorption process; d) purifying hydrogen remaining in shifted stream to create purified hydrogen fuel stream and purge gas stream; e) feeding purified hydrogen fuel stream to process fired heaters; and f) recycling purge gas stream to reactor/furnace section.    USE - For reducing the carbon dioxide emissions of a petroleum refinery, petrochemical or hydrogen plant by utilizing a low carbon hydrogen stream to fuel the process fired heaters and capturing the carbon dioxide stream pre-combustion (claimed).    ADVANTAGE - The process is efficient and economical technique for reducing the carbon dioxide emissions in a refinery; and eliminates the need for post combustion carbon dioxide capture from fired heaters (at atmospheric pressure and in dilute phase) in a petroleum refinery, thus achieves environmental targets by capturing carbon dioxide in a centralized facility and provides fuel gas low in carbon to the fired heaters.    DETAILED DESCRIPTION - Reducing the carbon dioxide emissions of a petroleum refinery, petrochemical or hydrogen plant by utilizing a low carbon hydrogen stream to fuel the process fired heaters and capturing the carbon dioxide stream pre-combustion involves: a) feeding hydrocarbon feedstocks and steam to a steam reformer unit, where the steam reformer reactor unit contains reactor section and a furnace section, to create a synthetic gas stream; b) shifting the synthetic gas stream catalytically using a water gas shift unit to create a shifted synthetic gas stream; c) capturing the carbon dioxide from the shifted synthetic gas stream through a carbon dioxide absorption process; d) purifying the hydrogen remaining in the shifted synthetic gas stream after the step (c) to create a purified hydrogen fuel stream and a purge gas stream; e) feeding the purified hydrogen fuel stream to process fired heaters, the furnace section of the steam reformer, and/or other process users within the refinery; and f) recycling the purge gas stream from step (d) to the reactor section and/or the furnace section of the steam reformer unit, where the carbon emissions of the refinery are reduced by more than 20%.