On the retrofitting and repowering of coal power plants with post-combustion carbon capture: An advanced integration option with a gas turbine windbox

Retrofitting a significant fraction of existing coal-fired power plants is likely to be an important part of a global rollout of carbon capture and storage. For plants suited for a retrofit, the energy penalty for post-combustion carbon capture can be minimised by effective integration of the capture system with the power cycle. Previous work on effective integration options has typically been focused on either steam extraction from the power cycle with a reduction of the site power output, or the supply of heat and electricity to the capture system via the combustion of natural gas, with little consideration for the associated carbon emissions. This article proposes an advanced integration concept between the gas turbine, the existing coal plant and post-combustion capture processes with capture of carbon emissions from both fuels. The exhaust gas of the gas turbine enters the existing coal boiler via the windbox for sequential combustion to allow capture in a single dedicated capture plant, with a lower flow rate and a higher CO2 concentration of the resulting flue gas. With effective integration of the heat recovery steam generator with the boiler, the existing steam cycle and the carbon capture process, the reference subcritical unit used in this study can be repowered with an electricity output penalty of 295 kWh/tCO2 – 5% lower than a conventional steam extraction retrofit of the same unit – and marginal thermal efficiency of natural gas combustion of 50% LHV – 5% point higher than in a configuration where the gas turbine has a dedicated capture unit

Applications of emerging technologies in the drinking water sector

This chapter explores the application of emerging technologies for waterborne pathogen detection from a market perspective. The water market, particularly in terms of monitoring, is heavily driven by regulation and regulatory compliance. Adoption of new technologies for the detection of pathogens can be challenging within this framework. This chapter will first describe the application of water safety plans (WSPs)and the water safety frameworks (WSF) in various countries, to set the background in which water monitoring is performed across the globe. There will be a particular focus on the situation in the UK as an in-depth case study. The chapter will also identify those pathogens which are currently of most concern to the market, providing a perspective from a public health point of view as well as the market view of existing technologies. Finally, the chapter will conclude by discussing future trends and the challenges of bringing new technologies to market in the water monitoring sector

Fuel Cells

Fuel cells are electrochemical devices capable of converting the chemical energy of a fuel (usually hydrogen, but also hydrocarbons and alcohols) into electricity and heat. Positive characteristics like high efficiency, low pollutant emissions and few maintenance requirements motivated a strong interest in this technology during the last decades, with R&D activities on different fuel cell types and applications going on around the world. In this chapter, after an introduction regarding the general features of the technology and the main development focuses, a particular attention is devoted to the types that currently dominate the market and the research: the Polymer Electrolyte Membrane Fuel Cells (PEMFC) and the Solid Oxide Fuel Cells (SOFC). The corresponding sections present the state of the art of these technologies, together with the technical targets for future developments, as well as existing and prospective applications