Effect of low-density polyethylene on smoke emissions from burning of simulated debris piles

Abstract

Low-density polyethylene (LDPE) plastic is used to keep piled debris from silvicultural activities-activities associated with development and care of forests-dry to enable efficient disposal by burning. The effects of inclusion of LDPE in this manner on smoke emissions are not well known. In a combustion laboratory experiment, 2-kg mixtures of LDPE and manzanita (Arctostaphylos sp.) wood containing 0, 0.25, and 2.5% LDPE by mass were burned. Gaseous and particulate emissions were sampled in real time during the entire flaming, mixed combustion phase-when the flaming and smoldering phases are present at the same time-and during a portion of the smoldering phase. Analysis of variance was used to test significance of modified combustion efficiency (MCE)-the ratio of concentrations of fire-integrated excess CO 2 to CO 2 plus CO-and LDPE content on measured individual compounds. MCE ranged between 0.983 and 0.993, indicating that combustion was primarily flaming; MCE was seldom significant as a covariate. Of the 195 compounds identified in the smoke emissions, only the emission factor (EF) of 3M-octane showed an increase with increasing LDPE content. Inclusion of LDPE had an effect on EFs of pyrene and fluoranthene, but no statistical evidence of a linear trend was found. Particulate emission factors showed a marginally significant linear relationship with MCE (0.05 < P-value < 0.10). Based on the results of the current and previous studies and literature reviews, the inclusion of small mass proportions of LDPE in piled silvicultural debris does not appear to change the emissions produced when low-moisture-content wood is burned. In general, combustion of wet piles results in lower MCEs and consequently higher levels of emissions.Implications: Current air quality regulations permit the use of burning to dispose of silvicultural piles; however, inclusion of lowdensity polyethyelene (LDPE) plastic in silvicultural piles can result in a designation of the pile as waste. Waste burning is not permitted in many areas, and there is also concern that inclusion of LDPE leads to toxic air emissions.

Identification of gas-phase pyrolysis products in a prescribed fire: first detections using infrared spectroscopy for naphthalene, methyl nitrite, allene, acrolein and acetaldehyde

“…Naphthalene has been detected (via GC-MS) in tars that were condensed from gas-phase pyrolysis products of both live and dead southeastern fuels, such as live oak (Quercus virginiana) and swamp bay (Persea palustris) (Safdari et al, 2018). It has also been detected (Koss et al, 2018;Hosseini et al, 2014;Aurell et al, 2017) in the gas phase in laboratory burning experiments. The detection of gas-phase naphthalene from wildland fire emissions is thus not surprising, but this is the first report of its identification via IR spectroscopy.…”

Analysis of Chemical Compounds of Gaseous and Particulate Pollutants from the Open Burning of Agricultural HDPE Film Waste

“…PE also contributes to significant changes in CO emissions when incinerated together with agricultural byproducts. Hosseini et al (2014) reported that when a mixed specimen of manzanita (Arctostaphylos sp. ), which is native to North America, and LDPE was incinerated, the CO emission factor was different depending on the LDPE content, but also that the PE had an effect on the increase in combustion efficiency, so further statistical review would be needed.…”

Automated SEM-EDS Analysis of Transition Metals and Other Metallic Compounds Emitted from Incinerating Agricultural Waste Plastic Film

“…A Pitot tube (Testo 0635 2145, Testo Korea Ltd, Seoul, Korea) was inserted into the velocity traverse port and connected to an analyzer box (Testo 350k, Testo Korea Ltd, Seoul, Korea) to measure the wind speed by the differential pressure. In this infrastructure, the heat generated during combustion is naturally cooled through the duct, and the gas temperature of the velocity traverse port is set to be maintained at an average of less than 100 • C. The particulate pollutants generated in the flame, mixed combustion stage and the soot stage, were collected from the duct [44]. Particulate matter sampling was conducted at a wind speed of 1.75 ± 0.37 m 3 /min.…”

“…In order to secure the reliability of EDS-based chemical species analysis, a verified standard sample [7] (Micro-Analysis Consultants LTD) was used to conduct the spectral location standard and quantification calibration. and the soot stage, were collected from the duct [44]. Particulate matter sampling was conducted at a wind speed of 1.75 ± 0.37 m 3 /min.…”