Impact of Biogas and Waste Fats Methyl Esters on NO, NO2, CO, and PM Emission by Dual Fuel Diesel Engine
Abstract
:1. Introduction
2. Materials and Methods
3. Results and Discussion
4. Conclusions
- With the increase of the BG share in the engine fuel supply, the amount of carbon oxides increases significantly. It is caused by the change of parameters of the engine fuel supply at constant operating parameters. A change in the injection angle may result in CO emission reduction; however, the reduction is slight in relation to the engine emission powered solely by DF, as evidenced in other tests [42,45,47,49]. The place and method of BG injection is also important, i.e., the injection into the inlet manifold. The use of multi-point or even direct injection could clearly reduce CO emission.
- The presence of BG in the engine feed mixture significantly reduces NOx. However, if we analyze the emission of NO and NO2 separately, we can see a clear increase in the emission of NO2 toxic particles. It follows that the presence of BG in fuels has a negative impact on the qualitative and quantitative composition of nitrogen oxides emitted in exhaust fumes.
- Replacing DF with UCOME fuel reduces both NO and NO2. The use of UCOME + BG mixture in comparison to the engine power supply with DF + BG fuel shows a negligible reduction in the amount of NO2.
- A three- to four-times reduction of PM emission was detected when the liquid fuel DF was replaced by UCOME. On the other hand, the presence of BG had no significant effect on the amount of PM in the exhaust fumes, regardless of the liquid fuel used.
- The improvement of the composition of exhaust emissions can also be performed using other constructions of a diesel engine. The use of a turbocharged engine will result in better reduction of exhaust gases or the introduction of water into the combustion chamber.
Author Contributions
Funding
Conflicts of Interest
List of Symbols and Acronyms
A* | mass amount of gases, kmol·h−1 |
AF | air filter |
AM | synchronous engine |
B | share of x gas (CO, NO, NO2) in the exhaust, mg·kg−1 |
BG | biogas |
BGT | biogas tank |
CFPP | cold filter plugging point |
CH4 | methane |
CO | carbon monoxide |
CO2 | carbon dioxide |
CS | control system |
CSM | control system monitor |
DE | diesel engine |
DF | diesel fuel |
DFT | diesel fuel tank |
DM | diesel (liquid fuel) mass flow meter |
EA | emission analyzation system |
EP | exhaust pipe |
EPM | measurement probe for exhaust gases |
ES | exhaust silencer |
FT | fuel temperature measurement |
GC | gas pressure regulator and flow control value |
GSI | gas injector control system |
H2S | hydrogen sulfide |
IM | intake manifold |
kWhe | electricity unit |
M | molar mass of the i-th gas, kg·kmol−1 |
NO | nitric oxide |
NO2 | nitrogen dioxide |
NOx | oxides of nitrogen |
O2 | oxygen |
P | pressure in the exhaust manifold, Pa |
PC | computer |
PM | particulate matter |
R | universal gas constant, J·kg−1·K−1 |
T | exhaust gases temperature, K |
UCO | used cooking oil |
UCOME | use cooking oil methyl ester |
UCOMET | waste cooking oil methyl ester tank |
V* | exhaust gases flow, in normal m3·h−1 |
WCO | waste cooking oil |
WS | weather station |
X | mass stream for NO, NO2, PM, and CO, mg·h−1 |
y | quantitative share of the i-th gas |
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Parameter | Engine |
---|---|
Engine type/model | Vertical in-line diesel engine |
Application | Power generator |
No. of cylinders | 2 |
Rated speed (rpm) | 3600 |
Rated power (kW) | 9.76 @ 3600 rpm |
Rated torque (Nm) | 30 @ 2600 rpm |
Displacement (cm3) | 570 |
Aspiration system Combustion system | Natural Ball-type swirl chamber |
Injection system | IDI Engine |
Common Name of Fatty Acids UCO (Used Cooking Oil) | (%) | |
---|---|---|
Myristic | (C 14:0) | 0.23 |
Palmitic | (C 16:0) | 8.56 |
Palmitoleic | (C 16:1) | 0.42 |
Stearic | (C 18:0) | 2.11 |
Oleic | (C 18:1) | 61.72 |
Linoleic | (C 18:2) | 18.18 |
Linolenic | (C 18:3) | 6.0 |
Arachidic | (C 20:0) | - |
Eicosenoic | (C 20:1) | - |
Other | 2.78 |
Fuel Property | Unit | UCOME | DF | BG |
---|---|---|---|---|
Viscosity @ 40 °C | mm2·s−1 | 4.79 | 2.91 | - |
Density @ 15 °C | kg·m−3 | 884.9 | 836.7 | 1.25 |
Calorific value | MJ·kg−1 | 38.2 | 42.6 | 17.15 |
CFPP | °C | −2 | −22 | - |
Cetane number | - | 57 | 52 | - |
Octane number | - | - | - | 110 [48] |
Flash point | °C | 244 | 59 | 630 [48] |
Component | Content | Uncertainty Level | |
---|---|---|---|
Hydrogen sulfide | H2S | 28 ppm | ± 10% |
Methane | CH4 | 59.9% (v/v) | ± 3% |
Carbon dioxide | CO2 | 41.7% (v/v) | ± 3% |
Oxygen | O2 | 0.7% (v/v) | ± 1% |
Emission [mg·h−1] | The Impact of Biogas | DF/UCOME | |
---|---|---|---|
DF+BG | UCOME+BG | ||
CO | +0.93 | +0.93 | + |
NO | +(−0.72) | +(−0.93) | + |
NO2 | +0.52 | −0.51 | + |
PM | −(−0.48) | −(−0.57) | + |
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Golimowski, W.; Krzaczek, P.; Marcinkowski, D.; Gracz, W.; Wałowski, G. Impact of Biogas and Waste Fats Methyl Esters on NO, NO2, CO, and PM Emission by Dual Fuel Diesel Engine. Sustainability 2019, 11, 1799. https://doi.org/10.3390/su11061799
Golimowski W, Krzaczek P, Marcinkowski D, Gracz W, Wałowski G. Impact of Biogas and Waste Fats Methyl Esters on NO, NO2, CO, and PM Emission by Dual Fuel Diesel Engine. Sustainability. 2019; 11(6):1799. https://doi.org/10.3390/su11061799
Chicago/Turabian StyleGolimowski, Wojciech, Paweł Krzaczek, Damian Marcinkowski, Weronika Gracz, and Grzegorz Wałowski. 2019. "Impact of Biogas and Waste Fats Methyl Esters on NO, NO2, CO, and PM Emission by Dual Fuel Diesel Engine" Sustainability 11, no. 6: 1799. https://doi.org/10.3390/su11061799
APA StyleGolimowski, W., Krzaczek, P., Marcinkowski, D., Gracz, W., & Wałowski, G. (2019). Impact of Biogas and Waste Fats Methyl Esters on NO, NO2, CO, and PM Emission by Dual Fuel Diesel Engine. Sustainability, 11(6), 1799. https://doi.org/10.3390/su11061799