Environmental Engineering Reference
In-Depth Information
Chapter 5
Energy and Supercritical Fluids
Richard L. Smith
Abstract
Global energy demand is expected to increase from 12.4 gigatons oil
equivalent (Gtoe) in 2010 to 16.7 Gtoe by 2035. Energy systems will need to be
redesigned or rethought to achieve the high efficiencies required to meet such
energy demands. Energy systems that take advantage of the favorable thermo-phys-
ical properties of supercritical fluids can help raise efficiency and this chapter intro-
duces several applications of energy systems that use supercritical fluids. These
include (i) transcritical cycles for heating (ii) cryogenic exergy recovery for lique-
fied natural gas transport, (iii) geothermal and waste heat energy, (iv) refrigeration,
(v) ultra-supercritical steam generators, (vi) biofuel synthesis, (vii) hydrothermal
conversion of biomass and (viii) solvo-thermal processing of biomass with ionic
liquids. Supercritical fluids offer unique technological advantages in their use for
energy systems and increase cycle efficiencies and simplify chemical processing.
Keywords
Energy systems
·
Transcritical
·
Biomass
·
Ionic liquids
·
Supercritical
·
Hydrogenation
5.1
Energy Poverty and Global Energy Trends
The availability of energy directly affects the quality of life in the world as more
than 1.3 billion people live without electricity and more than 2.6 billion people
live without clean cooking facilities (IEA
2014
). The lack of electricity and clean
cooking facilities is referred to as energy poverty (Fig.
5.1
). Presently, there is wide-
spread energy poverty in sub-Saharan Africa, India, developing Asia, China and
Latin America. Energy poverty can be expected to increase as both the world popu-
lation and global energy demand increase.
