Addressing Technology Uncertainties in Power Plants with Post-Combustion Capture

AbstractRisks associated with technology, market and regulatory uncertainties for First-Of-A-Kind fossil power generation with CCS can be mitigated through innovative engineering approaches that will allow solvent developments occurring during the early stage of the deployment of post-combustion CO2 capture to be subsequently incorporated into the next generation of CCS plants. Power plants capable of improving their economic performance will benefit financially from being able to upgrade their solvent technology. One of the most important requirements for upgradeability is for the base power plant to be able to operate with any level of steam extraction and also with any level of electricity output up to the maximum rating without capture. This requirement will also confer operational flexibility and so is likely to be implemented in practice on new plants or on any integrated CCS retrofit project

Platelet signaling: a complex interplay between inhibitory and activatory networks

The role of platelets in hemostasis and thrombosis is dependent on a complex balance of activatory and inhibitory signaling pathways. Inhibitory signals released from the healthy vasculature suppress platelet activation in the absence of platelet receptor agonists. Activatory signals present at a site of injury initiate platelet activation and thrombus formation; subsequently, endogenous negative signaling regulators dampen activatory signals to control thrombus growth. Understanding the complex interplay between activatory and inhibitory signaling networks is an emerging challenge in the study of platelet biology and necessitates a systematic approach to utilize experimental data effectively. In this review, we will explore the key points of platelet regulation and signaling that maintain platelets in a resting state, mediate activation to elicit thrombus formation or provide negative feedback. Platelet signaling will be described in terms of key signaling molecules that are common to the pathways activated by platelet agonists and can be described as regulatory nodes for both positive and negative regulators. This article is protected by copyright. All rights reserved

Financing new power plants ‘CCS Ready’ in China–A case study of Shenzhen city

AbstractWe evaluate the benefits of a ‘CCS Ready Hub’ approach, a regional ‘CCS Ready’ strategy, which not only includes a number of new coal-fired power plants but also integrates other existing stationary CO2 emissions sources, potential storage sites and potential transportation opportunities into an overarching simulation model. A dynamic top-down simulation model was built based on economic decision criteria and option pricing theory. The model inputs and assumptions build on spatial sampling and analysis using a geographic information system (GIS) approach, engineering assessment of local projects and outputs of a CCS retrofitting investment evaluation through cost cash flow modelling. A case study of Shenzhen city in the Pearl River Delta area in Guangdong in southern China is presented, based on engineering and cost assessment studies and stakeholder consultations and building on existing geological surveys and infrastructure plans. The simulation results show that financing ‘CCS Ready’ at regional planning level rather than only at the design stage of the individual plant (or project) is preferred since it reduces the overall cost of building integrated CCS systems. On the other hand, we found the value of considering existing stationary CO2 emissions sources in CCS ready design. Therefore, we recommended that making new plants CCS ready or planning a CCS ready hub should consider existing large emissions sources when possible

GRID and docking analyses reveal a molecular basis for flavonoid inhibition of src-family kinase activity

Flavonoids reduce cardiovascular disease risk through anti-inflammatory, anti-coagulant and anti-platelet actions. One key flavonoid inhibitory mechanism is blocking kinase activity that drives these processes. Flavonoids attenuate activities of kinases including phosphoinositide-3-kinase (PI3K), Fyn, Lyn, Src, Syk, PKC, PIM1/2, ERK, JNK, and PKA. X-ray crystallographic analyses of kinase-flavonoid complexes show that flavonoid ring systems and their hydroxyl substitutions are important structural features for their binding to kinases. A clearer understanding of structural interactions of flavonoids with kinases is necessary to allow construction of more potent and selective counterparts. We examined flavonoid (quercetin, apigenin and catechin) interactions with Src-family kinases (Lyn, Fyn and Hck) applying the Sybyl docking algorithm and GRID. A homology model (Lyn) was used in our analyses to demonstrate that high quality predicted kinase structures are suitable for flavonoid computational studies. Our docking results revealed potential hydrogen bond contacts between flavonoid hydroxyls and kinase catalytic site residues. Identification of plausible contacts indicated that quercetin formed the most energetically stable interactions, apigenin lacked hydroxyl groups necessary for important contacts, and the non-planar structure of catechin could not support predicted hydrogen bonding patterns. GRID analysis using a hydroxyl functional group supported docking results. Based on these findings, we predicted that quercetin would inhibit activities of Src-family kinases with greater potency than apigenin and catechin. We validated this prediction using in vitro kinase assays. We conclude that our study can be used as a basis to construct virtual flavonoid interaction libraries to guide drug discovery using these compounds as molecular templates

Mind the gap: connexins and pannexins in platelet function

Connexins are a family of gap junction forming proteins widely expressed by mammalian cells. They assemble into hexameric hemichannels, which can either function independently or dock with opposing hemichannels on apposite cells, forming a gap junction. Pannexins are structurally related to the connexins but extensive glycosylation of these channels prevents docking to form gap junctions and they function as membrane channels. Platelets express pannexin-1 and several connexin family members (Cx37, Cx40 and Cx62). These channels are permeable to molecules up to 1,000 Daltons in molecular mass and functional studies demonstrate their role in non-vesicular ATP release. Channel activation is regulated by (patho)physiological stimuli, such as mechanical stimulation, making them attractive potential drug targets for the management of arterial thrombosis. This review explores the structure and function of platelet pannexin-1 and connexins, the mechanisms by which they are gated and their therapeutic potential

Valuing Responsive Operation of Post-combustion CCS Power Plants in Low Carbon Electricity Markets

AbstractThis work considers the potential value in the additional flexibility of CCS post-combustion power plants gained by varying the operating CO2 capture level. The continuous relationship between CO2 capture level and the specific electricity output penalty is illustrated, and a new methodology is proposed for maximising net plant income through optimising the operating capture level. This methodology allows the plant to respond to electricity prices, fuel prices, and carbon reduction incentives including CO2 prices and premium payments for low carbon electricity. The implications for flexible operation under different market scenarios are qualified, and the indicative value to plant operators is determined

Vacuum Assisted Acidification: A Novel, Robust and Accurate Technique for the Measurement of CO 2 Loading in Solvents and its Application in Post Combustion Capture

AbstractA method for measuring the CO2 loading of post combustion capture solvents has been developed which first separates CO2 from the solvent by acidification of the solvent under vacuum conditions, then traps the CO2 via deposition, and finally quantifies the CO2 by pressure measurement in a calibrated volume. A preliminary comparative assessment shows that the measurement accuracy and precision of the method compares favorably to other methods currently used at post combustion capture research facilities and that there is potential for continuing development of the method for use in industrial field applications

Developing national CCS capacity and advanced skills:Examples from the UK

AbstractRapidly training researchers involved in carbon capture and storage (CCS) and advancing fundamental understanding of the entire chain is vital to achieve CCS deployment in a timescale aligned with global emission reduction targets. This paper introduces a number of initiatives that are building UK CCS capacity, focussing on activities involving the academic community such as the UK CCS Research Centre (www.ukccsrc.ac.uk) and a number of postgraduate training programmes. These and other examples illustrate the benefits associated with academic-industry collaboration, as well as providing valuable opportunities to accelerate development of suitably trained people and CCS technology in an academic context