MSU NIST Extension Project: Testing of an Adsorber (Scrubber) for Fume Hood Exhaust at the MSU Safety and Risk Management Building.

As part of a previous project, i.e., the MSU EPICenter Project (Williams et al., 2000), which was completed without the involvement of this writer, an adsorber for fume hood exhaust and an associated microwave based regenerator for the adsorbent were installed at the MSU Safety and Risk Management Building. Both the adsorber and regenerator were designed and fabricated by CHA Corporation of Laramie, Wyoming. The writer supervised testing of both the adsorber and regeneration systems. Some improvements in the design and operation of the regenerator were also made during this later project.

The important results of the experimental evaluation of the adsorber and regenerator performance are scheduled to appear in the ASCE Journal of Environmental Engineering, March 2004. 

Various images of the adsorber, regenerator, and test sequence are shown below.


Williams, K., Berkebile, R., McLennan, J., Achelpohl, K., and Svec, P., The NIST Report for the MSU EPICenter, September 2000, National Institute of Standards and Technology, Washington, DC.

Figure 1. The project site: the MSU Safety and Risk Management Building


Figure 2. Fan which directs fume hood exhaust downward into the adsorber and upward to a location above the roof.

Figure 3. The fume hood adsorber shown detached from ducts. Dimensions of the adsorber are approximately 1 x 1 x 1 m.


Figure 4. Chemical being injected into the fume hood at a controlled rate.


Figure 5. Chemical container shown within the fume hood.


Figure 6. Multiple containers for high rate injection of chemical into the fume hood.


Figure 7. One of the analyzers used to measure the concentration of chemical flowing into or out of the adsorber.


Figure 8. The adsorber with the top removed and adsorbent removed. It is a radial flow unit which contains separately two types of adsorbents.


Figure 9. Close-up of the radial chambers that contain the adsorbents.

Figure 10. The adsorbent regenerator. In operation, the adsorbent flows vertically downward through the black tube shown near the center of the image. Basically, the absorbents are heated by microwaves to drive off the adsorbed chemical  which is transferred to nitrogen purge gas. The purge gas is then further treated before being allowed to enter the atmosphere.


Figure 11. After regeneration, the adsorbent is transferred to a container and weighed. In normal use, the adsorbent flows directly back into the adsorber.

Figure 12. Nitrogen was used as a purge gas for the regeneration process.