Bourns College of Engineering – Center for Environmental Research and Technology University of California, Riverside Evaluation of Emissions/Residue Testing.

Bourns College of Engineering – Center for Environmental Research and Technology

University of California, Riverside

Evaluation of Emissions/Residue Testing from a Thermal Conversion Process Using a Municipal

Solid Waste Feedstock

By

William A. WelchUniversity of California, Riverside

Bourns College of Engineering

Center for Environmental Research and Technology

Presentation to

California Integrated Waste Management Board

September 20, 2005



International Environmental Solutions Facility International Environmental Solutions Facility Romoland, CARomoland, CA



Feedstock (Post-MRF Residual)Feedstock (Post-MRF Residual)



Air Emissions SamplingAir Emissions Sampling



Test MatrixTest Matrix

• Approximately 80 hours of testing over 8 days

• Air Emissions– Continuous analysis conducted for nitrogen oxides, carbon

monoxide, carbon dioxide, and oxygen– Integrated samples acquired for determination of total particulate

matter, sulfur dioxide, toxic organics, volatile organic compounds, formaldehyde, multiple metals, mercury, dioxins, and furans

• Feedstock– Process weight, heating value, organic and inorganic species

• Solid Residues– Process weight, heating value, organic and inorganic species



Air EmissionsAir Emissions

• No regulatory limits currently in place in the US for thermal conversion processes

• Comparison to other emissions limits– Results and/or regulatory limits converted to normalized

concentration values for comparison – US EPA limits for starved air combustors– South Coast Air Quality Management District (SCAQMD) permit

limits for municipal solid waste (MSW) incinerators– European (German) limits for thermal conversion processes

• IES Results– Tests show compliance with all existing limits for criteria

pollutants, except for NOx– Company currently developing NOx control strategy– Health Risk Assessment currently underway



Exhaust Air Emissions Concentrations Exhaust Air Emissions Concentrations and Regulatory Standardsand Regulatory Standards

(concentrations in mg/m3 unless otherwise noted)

Notes: PM = particulate matter, NOx = oxides of nitrogen, CO = carbon monoxide, SO2 = sulfur dioxide, HCl = hydrogen chloride, Cd = Cadmium, Pb=Lead, Hg=Mercury

* NOx emissions complied with the SCAQMD research permit limits issued to IES for this testing

Emissions Standards/Source PM NOx CO SO2 Dioxins/

Furan (TEQ) (ng/Nm3)

Cd Pb Hg

U.S. EPA limits (starved air combustors) 18 219.8 89.2 61.2 0.41 0.01533 0.1533 0.0613

SCAQMD MSW incinerator permit limits (2004) 27 350-399 118 50.6 30 0.04 0.44 0.08

German limits 14 281 70.2 70.2 0.14 0.042 0.7 0.042

IES Romoland 3.87 425* 4.0 2.02 0.035 0.00015 0.00028 0.00056



Exhaust Air Emissions Concentrations and Exhaust Air Emissions Concentrations and Regulatory StandardsRegulatory Standards

NO

x

CO

SO

2

PM

Dio

xins/

Fura

ns

Cd (x

100)

Pb (x

100)

Hg (x

100)

0

50

100

150

200

250

300

350

400

450

Concentration

(mg/Nm3 @ 7% O2)

Air Emissions Component

IES RomolandGerman limitsU.S. EPA limits (starved air combustors)SCAQMD MSW incinerator permit limits (2004)

ng/Nm3



Feedstock and Residue Feedstock and Residue AnalysesAnalyses

• No way to obtain “representative” sample of feedstocks or residues due to the highly heterogeneous nature of mixed MSW

• Some general trends can be gathered from the results– There is good potential of post-process recycling of glass and

metals from the char– Volatile metals (Hg, As, Cd, Pb) are found in higher concentrations

in the baghouse residue than the char– Heavier molecular weight metals are concentrated in the char– Very low levels of toxic organic compounds found in residues– Significant heating value remains in the char

• Future work– Need dioxin/furan and TCLP analyses on char/residues– Strategy for extracting additional energy from char– Strategy for stabilizing char/ash residues for safe disposal



Inorganic Analyses of Feedstock Inorganic Analyses of Feedstock and Solid Residuesand Solid Residues

(example only; not representative of bulk stream)(example only; not representative of bulk stream)

Cl NH3 NO3 Nitrite SO3 As Ba Cd Cr Cr VI

MSW Feedstock 286 4.7 ND 0.172 584 ND 24.6 1.83 16.7 ND

Residual Char 800 1.25 ND ND 962 6.02 176 4.67 41.6 ND

Baghouse Residue 2330 1.11 0.177 3020 5.62 747 49.7 89.5 0.419

(concentrations in mg/kg)

Co Cu Pb Hg Ni Ag V Zn

MSW Feedstock ND 11,300 17.9 ND 6.33 ND 10.5 50.0

Residual Char 5.9 667 645 ND 64.7 1.64 23.7 2660

Baghouse Residue 6.98 660 1740 5.25 72.0 1.66 27.5 5960

Notes: Cl =chloride, NH3 = ammonia (as nitrogen), NO3 = nitrate, SO3 = sulfate, As = arsenic, Ba = barium, Cd = cadmium, Cr = chromium, Cr VI = chromium VI, ND = none detected

Notes: Co = cobalt, Cu = copper, Pb = lead, Hg = mercury, Ni = nickel, Ag = silver, V = vanadium, Zn = zinc, ND = none detected



Organic Analyses of Feedstock and Organic Analyses of Feedstock and Solid ResiduesSolid Residues

(example only; not representative of bulk stream)(example only; not representative of bulk stream)

HHV

(Btu/lb) TKN

(mg/kg) TOC (%

wt.) Benzene (mg/kg)

Ethylbenzene (mg/kg)

Toluene (mg/kg)

MSW Feedstock 2640 N/A N/A ND ND ND

Residual Char 1070 1230 8.49% 0.254 0.141 0.688

Baghouse Residue N/A ND 0.7% 0.177 3020 5.62

Notes: HHV = Higher Heating Value, TKN = Total Kjeldahl Nitrogen, TOC = Total Organic Carbon



ConclusionsConclusions

• Test results show compliance with most air pollution regulations. Modifications to control equipment may be necessary to meet NOx or other health risk standards

• Further characterization of char and baghouse residues recommended for development of solid waste treatment and disposal strategy

Bourns College of Engineering – Center for Environmental Research and Technology University of California, Riverside Evaluation of Emissions/Residue Testing.

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