Adsorption reverse electrodialysis driven by power plant waste heat to generate electricity and provide cooling

Abstract

Summary Steam power plants release more than half of the primary energy input as ultra low temperature heat below 40∘C into the environment causing thermal pollution. The emitted heat has a very low exergy content making it challenging to use as heat input by another process. Adsorption desalination combined with reverse electrodialysis can be powered by this heat and convert it into electricity. Thus, the system can mitigate thermal pollution and generate electricity at the same time. This study combines a validated reverse electrodialysis model with a dynamic adsorption desalination model that is validated with experimental data within this work. The experiments were conducted using a small‐scale adsorption desalinator and silica gel proving the feasibility of the regeneration at heat source temperatures as low as 40∘C. The simulations of the integrated system analyse different heat integration scenarios showing exergy efficiencies up to 15% and energy efficiencies up to 0.55%. Hence, the system could generate 65 kW electricity from a 20 MW heat source considering pumping losses.

Electro‐membrane reactor: A powerful tool for green chemical engineering

“…The results indicate good stability over operational times of up to 55 h in terms of solution properties, power generation, and thermal consumption. Santori et al 87,88 combined RED with adsorption desalination in a closed‐loop system to generate electricity from low‐grade heat. RED was used to generate electricity by mixing two salt solutions with different concentrations.…”

Water Vapor Adsorption by Porous Materials: From Chemistry to Practical Applications

“…A few works investigated small-scale − and pilot-scale , AD systems, with only one being operated on an industrial scale . On the other hand, modeling and simulation of AD systems are reported on conventional two-bed systems (as in Figure ) − and multibed and multistage systems. − Different numerical simulations were developed at various depths and accuracy. − …”

An estimate of the ultralow waste heat available in the European Union

“…The major waste heat source is therefore the low grade heat from the combined cycle with an upper efficiency assumed at 65% [77]. This is a conservative value of efficiency which leaves only 35% of the primary energy as waste heat at a temperature of 40°C [78]. Energy consumption and waste data from the soda ash industry in the EU in 2018 are reported in Table 17.…”