The Comparison Between Carbon Capture And Storage(CCS) And Artificial Forest Carbon Sequestration

Excessive emission of CO₂ has led to increasingly serious global warming.The concept that human society should control CO₂ emissions to slow or even reverse global warming has become a general consensus among countries.China is the world’s largest carbon emitter,accounting for 28.3% of global carbon emissions in 2016.One of the reasons is that coal still plays an important role of China’s primary energy consumption.Carbon trading market will be opened all over the contry in 2017.As a result,coal-fired power plants and coal chemical plants have to search for large-scale carbon reduction technology to reduce cost.Carbon capture and storage（CCS）is a mature and promising large-scale carbon reduction technology.In 2016,it has stored almost 30 Mt CO₂,growing by 7.5% every year.However,unprofitable challenges and unclear technical path slowed down its development process in China.On the other hand,artificial forest carbon sequestration,which utilizes forest carbon pool to store CO₂,becomes prevailing in carbon trading market.But its cost and carbon sink amount of carbon sequestration are not well-studied in China.This dissertation conducts modeling and simulation of CCS and artificial forest carbon sequestration respectively,and sets up economic models to calculate and compare their unit cost.For CCS,Aspen with mathematical model is accepted to simulate and compare different technology paths.For artificial forest,CO₂ FIX model is used to simulate two actual programs of artificial forest carbon sequestration,which are in Hebei and Inner Mongolia province.The result shows that: firstly,CCS’s unit cost of reduction emission ranges from 190 to 410 CNY/t CO₂.The lowest unit cost of reduction emission appears in CCS with pre-combustion capture and pipeline transport,which is 192 CNY/t CO₂.Post-combustion capture CCS is more expensive than pre-combustion capture CCS,with almost twice unit cost of reduction emission compared to the latter.Second,unit costs of reduction emission vary obviously in artificial forests with different geographical conditions and vegetation types.The unit cost of reduction emission is 126 CNY/t CO₂ in Hebei artificial forest,while it rises to 183 CNY/t CO₂ in Inner Mongolia.Thirdly,CCS’s unit cost of emission reduction is higher than that of artificial forest carbon sequestration.CCS with post-combustion capture is nearly 2³ times more expensive than artificial forest carbon sequestration.However when considering the proper technology paths,like pre-combustion and pipeline transport,the unit cost of emission reduction will decrease to the same level of inefficient artificial forest carbon sequestration.