Circulating Regeneration and Resource Recovery of Flue Gas Desulfurization Residuals using a Membrane Electroreactor: From Lab Concept to Commercial Scale

摘要

Desulfurization residuals (using NaOH sorbent) were regenerated electrochemicalry, and at the same time sulfur in the flue gas was recovered as H_2SO_4 and H_2 was produced as a clean energy. Since industrialization should always be the final goal to pursue for lab technologies and the evolution of pilot- and full-scale commercial reactors has taken place relatively slowly, this paper is aimed to develop an electroreactor on a sufficiently large scale to evaluate the application potential of the proposed regeneration process. The following key design parameters are discussed: (1) voltage distributions over electrode, membrane, and electrolyte; and (2) scaling up correlation based on lab-scale reactor operation parameters. Thereafter, in the developed reactor, the desulfurization residuals using NaOH sorbent from a semidry flue gas desulfurization (FGD) facility of a power plant in Shandong Province were regenerated and it is significant to note that the electrochemical efficiency of the designed reactor is comparable to that of the chlor-alkali industry, showing that the technology is environmentally friendly and economically feasible. If this technology is to be employed for FGD, the facility could be a profit-generating manufacturing part instead of a currently money-consuming burden for the plants.