Fig. 2 shows the experimental setup

Fig. 2 shows the experimental setup for gas removal efficiency test of the present PPWS. The PPWS consists of a spray nozzle (model TF28, BETE Fog Nozzle, Inc., Greenfield, MA, USA), a main body with the MPPM (0.3 m 0.3 m 0.3 m), a demister, and a liquid reservoir with an electrical conductivity meter and a pH meter.