ENGINEERING

A recent project deviated from the usual physics and neuroscience projects required to better understand phenomenon of time.  It was that of barbecue smoke with its potential to inflict harmful health consequences due to the volatile organic compounds it contains.  A small study was generated to see what the efficacy might be by using activated carbon scrubbers for the smoke from grills whose energy source was woodchips or charcoal.

The main source of inspiration and energy for this project since day one has been our volunteer employee, Nikolas Kalamas who provides this abstract.

 

Removing Harmful Volatile Organic Compounds (VOCs) and PM₂.₅ From Barbecue Smoke Leaving Desirable Sweet Syringol Behind

 

ABSTRACT

BBQ smoke contains volatile organic compounds (VOCs) and particle masses (e.g., PM_2.5) that are hazardous to health.  Carbon activated scrubbers have been used to adsorb them. However, differential scrubbing of BBQ smoke leaving behind the sweet-smelling compound, Syringol, has not been attempted.  Coincidentally, Syringol is a polar molecule.  And activated carbon is more effective at removing non-polar molecules because it is non-polar. Therefore, it was hypothesized that BBQ smoke can be cleaned of toxic compounds leaving some Syringol that prompts barbecuing.

It was also hypothesized that even scrubbed invisible barbecue smoke may contain some harmful organic compounds.  And, a conventional barbecue can be redesigned to incorporate carbon scrubbers.

A modified grill carried the smoke via hoses to scrubbers of various concentrations (0, 25, 50,75, 100%), to TVOC/PM_2.5 meters, and to portals for olfactory sampling and smoke visibility measurements.  Fig. 1.  Energy sources were either wood chips, charcoal, or propane.  Up TO 20 trials for each condition were performed with randomization.

Differential adsorption was dramatic. Fig. 2.   For example, for woodchips using a 50% scrubber concentration, the percent remaining Syringol was 60% compared to 6% for TVOC – a 10 fold difference (p< 0.05 Mann-Whitney U).  Compared to ambient air, invisible smoke was associated with some unhealthy TVOC/PM _2.5 levels.  Half of the PM_2.5 values were above the unhealthy level (p<0.05).

The proposed BBQ design (Fig. 3) divides a conventional grill into 3 compartments separated by carbon scrubber partitions.  The outside compartments provide the energy source.  Scrubbed relatively clean smoke passes through the carbon partition to reach food in the central compartment. 

 

Fig 1

Fig 3