Diesel particulates

Additional research for both ethanol and methanol showed that the amount of ignition improver could be reduced by systems increa sing engine compression (63). Going from 17 1 to 21 1 reduced the amount of TEGDN requited for methanol from 5% by volume to 3%. Ignition-improved methanol exhibited very low exhaust emissions compared to diesels particulate emissions were eliminated except for small amounts associated with engine oil, NO was even lower with increased compression, and CO and hydrocarbons were also below diesel levels. 

Methanol use would also reduce pubHc exposure to toxic hydrocarbons associated with gasoline and diesel fuel, including ben2ene, 1,3-butadiene, diesel particulates, and polynuclear aromatic hydrocarbons. Although pubHc formaldehyde exposures might increase from methanol use in garages and tunnels, methanol use is expected to reduce overall pubHc exposure to toxic air contaminants. 

J. Dinesen, S.S. Nissen, and H. Christensen, Electrochemical Diesel Particulate Filter, SAE paper 980547, Diesel Exhaust Aftertreatment (SP-1313) 197-201 (1998). 

Standardization. Standardization in analytical chemistry, in which standards are used to relate the instrument signal to compound concentration, is the critical function for determining the relative concentrations of species In a wide variety of matrices. Environmental Standard Reference Materials (SRM s) have been developed for various polynuclear aromatic hydrocarbons (PAH s). Information on SRM s can be obtained from the Office of Standard Reference Materials, National Bureau of Standards, Gaithersburg, MD 20899. Summarized in Table VII, these SRM s range from "pure compounds" in aqueous and organic solvents to "natural" matrices such as shale oil and urban and diesel particulate materials. 

The small particles are reported to be very harmful for human health [98]. To remove particulate emissions from diesel engines, diesel particulate filters (DPF) are used. Filter systems can be metallic and ceramic with a large number of parallel channels. In applications to passenger cars, only ceramic filters are used. The channels in the filter are alternatively open and closed. Consequently, the exhaust gas is forced to flow through the porous walls of the honeycomb structure. The solid particles are deposited in the pores. Depending on the porosity of the filter material, these filters can attain filtration efficiencies up to 97%. The soot deposits in the particulate filter induce a steady rise in flow resistance. For this reason, the particulate filter must be regenerated at certain intervals, which can be achieved in the passive or active process [46]. 

Levsen K (1988) The analysis of diesel particulate. Eresenius ZAnal Chem 331 467-478. 

Coal ash, coal fly ash, power station fly ash, incinerator ash, vehicle exhaust particulates, urban dust, atmospheric dust, metal smelter dust, welding dust, diesel particulates, particulates on filter media Sewage sludge, wastewater... 

CRMs for Contaminants in Environmental Matrices For nearly two decades NIST has been involved in the development of SRMs for the determination of organic contaminants such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and chlorinated pesticides in natural environmental matrices such as fossil fuels (Hertz et al.1980 Kline et al. 1985), air and diesel particulate material (May and Wise 1984 Wise et al. 2000), coal tar (Wise et al. 1988a), sediment (Schantz et al. 1990, 1995a Wise et al. 1995), mussel tissue (Wise et al. 1991 Schantz et al. 1997a), fish oil, and whale blubber (Schantz et al. 1995b). Several papers have reviewed and summarized the development of these environmental matrix SRMs (Wise et al. 1988b Wise 1993 Wise and Schantz 1997 Wise et al. 2000). Seventeen natural matrix SRMs for the determination of organic contaminants are currently available from NIST with certified and reference concentrations primarily for PAHs, PCBs, chlorinated pesticides, polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofiirans (PCDFs) see Table 3.11. 

Diesel Particulate Extract PAHs (8) PAH (23) Nitro-PAHs (18)... 

Diesel Particulate Matter (Industrial Forklift) PAHs (II) PAHs (28)... 

NIST SRM diesel particulate matter flocculation-based batch equilibrium method with 59-d equilibration time, air-bridge equilibrium with 123-d equilibration time, Nguyen et al. 2004)... 

Matsuzawa, S., Masser-Ali, L., Garrigues, P. (2001) Photolytic behavior of polycyclic aromatic hydrocarbons in diesel particulate matter deposited on the ground. Environ. Sci. Technol. 36, 3139-3143. 

Catalyst activities, specific, 10 47t Catalyst additives, nitrogen oxide emissions and, 11 719 Catalyst-based diesel particulate filter (CB-DPF) technology, 10 61-62 Catalyst bed(s)... 

DCL DDGS DEFC DICI DISI DME DMFC DOE DP DPF Direct coal liquefaction Distillers dried grains with solubles Direct ethanol fuel cell Direct-injection compression ignition Direct-injection spark ignition Dimethylether Direct methanol fuel cell Department of Energy (USA) Dynamic programming Diesel particulate filter... 

FIG. 17-56 Typical porous wall tube array diesel particulate filter. 

SRM 1650A Soot diesel particulate matter heavy du... 

SRM 1650A ( ) Diesel Particulate Organic Constituents NIST (being replaced)... 

Sidhu S, Gullet B, Striebich R, Klosterman JR, Contreras J, DeVito M (2005) Endocrine disrupting chemical emissions from combustion sources diesel particulate emissions and domestic waste open bum emissions. Atmos Environ 39 801-811... 

Andrews GE, Abbass MK, Williams PT, et al. 1989. Factors influencing the composition of the organic fraction of diesel particulates. Journal of Aerosol Science 20(8) 1373-1376. 

The extended SCR model has been integrated with other catalyst and diesel particulate filter (DPF) models in the Daimler exhaust gas after-treatment systems simulation environment ExACT. The model was also extended to other SCR catalytic materials [79]. 

Anke Giithenke, Daniel Chatterjee, Michel Weibel, Bernd Krutzsch, Petr Koci, Milos Marek, Isabella Nova and Enrico Tronconi, Current Status of Modeling Lean Exhaust Gas Aftertreatment Catalysts Athanasios G. Konstandopoulos, Margaritis Kostoglou, Nickolas Vlachos and Evdoxia Kladopoulou, Advances in the Science and Technology of Diesel Particulate Filter Simulation... 

Tong and Karasek (1984) diesel particulate matter (DPM). d Schuetzle and Daisey (1990) and references therein. 

TABLE 10.21 Direct Mutagenicities of Two Nitroazabenzo[a]pyrenes, Their N-Oxide Derivatives,u and 3,6-Dinitrobenzo[a]pyrenec Detected in Ambient and Diesel Particulate Matter15 and, for Comparison, l- and 3-Nitrobenzotalpyrene... 

TABLE 10.33 Concentrations of Selected Nitroarenes in Extracts of Diesel Particulate POM b... 

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