Assessing the potential of utilisation and storage strategies for post-combustion CO2 emissions reduction

The emissions reduction potential of three carbon dioxide handling strategies for post-combustion capture is considered. These are carbon capture and sequestration/storage (CCS), enhanced hydrocarbon recovery (EHR), and carbon dioxide utilization (CDU) to produce synthetic oil. This is performed using common and comparable boundary conditions including net CO2 sequestered based on equivalent boundary conditions. This is achieved using a “cradle to grave approach” where the final destination and fate of any product is considered. The input boundary is pure CO2 that has been produced using a post-combustion capture process as this is common between all processes. The output boundary is the emissions resulting from any product produced with the assumption that the majority of the oil will go to combustion processes. We also consider the “cradle to gate” approach where the ultimate fate of the oil is not considered as this is a boundary condition often applied to EHR processes. Results show that while CCS can make an impact on CO2 emissions, CDU will have a comparable effect whilst generating income while EHR will ultimately increase net emissions. The global capacity for CDU is also compared against CCS using data based on current and planned CCS projects. Analysis shows that current CDU represent a greater volume of capture than CCS processes and that this gap is likely to remain well beyond 2020 which is the limit of the CCS projects in the database

Formic acid synthesis using CO₂ as raw material: Techno-economic and environmental evaluation and market potential

The future of carbon dioxide utilisation (CDU) processes, depend on (i) the future demand of synthesised products with CO₂, (ii) the availability of captured and anthropogenic CO₂, (iii) the overall CO₂ not emitted because of the use of the CDU process, and (iv) the economics of the plant. The current work analyses the mentioned statements through different technological, economic and environmental key performance indicators to produce formic acid from CO₂, along with their potential use and penetration in the European context. Formic acid is a well-known chemical that has potential as hydrogen carrier and as fuel for fuel cells. This work utilises process flow modelling, with simulations developed in CHEMCAD, to obtain the energy and mass balances, and the purchase equipment cost of the formic acid plant. Through a financial analysis, with the net present value as selected metric, the price of the tonne of formic acid and of CO₂ are varied to make the CDU project financially feasible. According to our research, the process saves CO₂ emissions when compared to its corresponding conventional process, under specific conditions. The success or effectiveness of the CDU process will also depend on other technologies and/or developments, like the availability of renewable electricity and steam

Effects of Cytokines and Immunosuppressants on the Production of Serum Amyloid A Protein and C-reactive Protein in HepG2 Cells

C-reactive protein (CRP) and serum amyloid A protein (SAA) are acute- phase proteins produced by the liver in response to inflammatory cytokines. The concentrations of these proteins in serum vary in parallel in most pathological conditions, but sometimes vary independently. CRP and SAA were determined in HepG2 cell culture medium supplemented with five immunosuppressants (corticosteroid, gusperimus hydrochloride, cyclosporin A, mizoribine and tacrolimus hydrate), with or without interleukin-1β(IL-1β) and interleukin-6 (IL-6). We also examined the effects of the immunosuppressants on the production of cytokines and changes in CRP and SAA production in HepG2 cells stimulated with the culture fluid from lipopolysaccharide (LPS) - treated monocytes. In HepG2 cells, production of CRP and SAA was greatly affected by IL-6 and IL-β, respectively. Prednisolone (PSL) suppressed CRP production, while it enhanced SAA production. The other four immunosuppressants did not affect CRP production, but inhibited SAA production. PSL significantly inhibited cytokine production in monocytes, while the other immunosuppressants enhanced it. In HepG2 cells incubated with the culture fluid from LPS-stimulated monocytes, CRP production was suppressed, while SAA production was enhanced. PSL suppressed CRP production in HepG2 cells by inhibiting IL-6 production in monocytes, whereas PSL increased SAA production through a direct action on the hepatoma cells. In contrast, the other immunosuppressive agents enhanced IL-β production in monocytes. The agents induced SAA production in the HepG2 cells but did not affect CRP production