To solve the problems of the high energy consumption of CO

2

regeneration and the superior difficulty of CO

2

utilization in the flue gas decarbonization system with traditional monoethanolamine (MEA) method

a novel ammonia d

ecarbonization system for producing NH

4

HCO

3

was proposed based on the water photovoltaic electrolysis for hydrogen production and Haber-Bosch ammonia synthesis process.This system utilized photovoltaic electrolysis of water to produce green hydrogen

which was further synthesized with N

2

to produce green ammonia (NH

3

). The NH

3

in solution form

reacted with CO

2

in flue gas in an absorption tower to generate NH

4

HCO

3

. Simultaneously

the rich liquor (containing NH

4

HCO

3

) was cooled and separated to produce NH

4

HCO

3

achieving the co-production of electricity

heat

and NH

4

HCO

3

with low carbon emissions

and avoiding the challenges associated with large-scale storage and utilization of CO

2

. Based on a 300 MW coal-fired unit

a simulation model of the system was established in Aspen Plus V11 software. Calculation and analysis results indicate that the system can remove 1.546 8 million tonnes of CO

2

annually from flue gas (with a decarbonization rate of 85%)

and produce 2.792 million tonnes of NH

4

HCO

3

1.034 2 million tonnes of by-product O

2

and 4.731 4 million tonnes of hot water annually. It requires the configuration of a photovoltaic power unit with an installed capacity of 2 594 MW and an ammonia production system with an annual output of 620 500 tonnes. The equivalent cost of carbon dioxide removal is 233.96 yuan per tonne.