Online measurement of PM from residential wood heaters in a dilution tunnel

Figures & data

Figure 1. Time-series of PM emissions from a Step-2 2015 NSPS cordwood stove in a dilution tunnel, IDC fueling protocol (Stove #9, August 7, 2019).

Table 1. 1405 TEOM 10-minute practical quantitation limit (PQL) at different sample flows, based on measurements made at 2 LPM sample flow.

TEOM flow	PQL	PQL (g/h), 500	PQL (g/h),
LPM	mg/m^3	cfm tunnel	DF of 50^a
0.5	0.144	0.122	0.245
1.0	0.072	0.061	0.122
2.0	0.036	0.031	0.061
5.0	0.014	0.012	0.024

^aExtractive sampling, assumes a nominal stack flow of 20 SCFM.

Figure 2. Deming regression of collocated PM from a 1405D 2-channel TEOM, 10-minute block average data from a high emitting NSPS Step-2 cordwood stove.

Figure 3. Model 1400AB Teom vs. Manual Emfab Filter PM (mg/m³) in a dilution tunnel at BNL, desiccated equilibration times of 0-Day, 1-Day, and 1-Week. Dotted lines are 1:1.

Figure 4. 1400AB Teom vs. Filter PM Concentration in a dilution tunnel, August 2016 – January 2017. Dotted line is 1:1.

Figure 5. TEOM model 1400 and 1405 vs. manual filter sample PM (mg/m³) for HLS cordwood tests.

Figure 6. 1405 TEOM vs. manual filter sample PM (mg/m³) for pellet stove tests.

Figure 7. (a) 1405 TEOM vs. manual filter sample PM (mg/m³), same number of filters. (b) 1405 TEOM vs. manual filter sample PM (mg/m³), more TEOM than manual filters. Square symbols represent two samples removed from the analysis.

Table 2. Summary of regression parameters, TEOM (model indicated in parentheses) vs. equilibrated manual filter sample (intercepts are not significant).

Data Set	Slope	Intercept, mg	R^2	N
BNL cordwood (1400)	0.867	−1.6	0.990	24
HLS cribwood (1400)	0.885	−1.0	0.960	36
HLS cordwood (1400)	0.826	−0.6	0.972	29
HLS cordwood (1405)	0.978	−0.8	0.971	82
HLS pellet (1405)	0.981	+0.3	0.880	42
HLS, same # filters^a (1405)	0.911	+0.2	0.971	70
HLS, TEOM># filters (1405)	0.983	−0.5	0.972	51

^a4 tests had more manual filters than TEOM filters and are not included here.

Figure 8. PM from a cordwood boiler measured with TEOMs at 25 and 80°C.

Table 3. Filter face velocities for different sampling methods.

Device	diameter	face velocity
and flow	mm	cm/s
TEOM 0.5 LPM	13	6.3
ASTM 0.10 CFM	38	3.8
EPA 5 G 0.5 CFM	94	3.4
PM2.5 FRM	42	20.1

Table 4. eBC to PM Ratio for twelve IDC runs on four different wood stoves.

IDC Phase	Startup	Load 1	Load 2	Load 3	Full Run
Median	0.10	0.03	0.03	0.08	0.04
SD	0.08	0.06	0.03	0.09	0.04
Max	0.30	0.21	0.07	0.31	0.14
Min	0.04	0.01	0.00	0.01	0.01

Figure 9. Mass loss from the TEOM filter when sampling dry clean air.

Figure 10. TEOM filter mass loss for 52 hours after the end of a dilution tunnel test run.

Table 5. Test run average PM emission rate (g/h) with different numbers of filters used.

Run	Duration	9 Filters	5 to 6 Filters	ratio
Date	hours	g/h	g/h
02/02/18	12.1	25.2	15.3	1.65
02/22/18	13.2	16.7	12.8	1.30
04/02/18	14.0	9.3	7.0	1.34
Average	13.1	17.1	11.7	1.46

Data availability statement

The data that support the findings of this study are available from the corresponding author, [GA], upon reasonable request.