Abstract

There are increasing interests in converting solid waste or lignocellulosic biomass into gaseous fuels and using reciprocating internal combustion engine to generate electricity. A widely used technique is gasification. Gasification is a process where the solid fuel and air are introduced to a partial oxidation environment, and generate combustible gaseous called synthesis gas or syngas. Converting solid waste into gaseous fuel can reduce landfill and create income for process owners. However, it can be very challenging to use syngas on a gaseous fueled spark ignited (SI) engine, such as a natural gas (NG) engine. NG engines are typically developed with pipeline quality natural gas (PQNG). NG engines can operate at lean burn spark ignited (LBSI), or stoichiometric with exhaust gas recirculation (EGR) spark ignited (SESI) conditions. This work discusses the LBSI engine condition. NG engines can perform very differently when fueled with nonstandard gaseous fuels such as syngas without appropriate tuning. It is necessary to evaluate engine performance in terms of combustion duration, relative knock propensity, and NOx emissions for such applications. Due to constraints in time and resources it is often not feasible to test such fuel blends in the laboratory. An analytical method is needed to predict engine performance in a timely manner. This study investigated the possibility of using syngas on an SI engine developed with PQNG. Engine performance was predicted using in house developed models and PQNG as the reference fuel. Laminar flame speed (LFS), adiabatic flame temperature (AFT), and auto-ignition interval (AI) are used to predict combustion duration, engine out NOx and engine knock propensity relative to NG at the target lambda values. Single cylinder research engine data obtained under lean burn conditions fueled with PQNG was selected as the baseline. LFS, AFT, and AI of syngas were computed at reference conditions. Lambda of operation was predicted for syngas to provide the same burn rate as NG at the reference lambda value for NG. Analysis shows that, using syngas at the selected lambda, the engine can have less engine out NOx emissions and less knock propensity relative to NG at the same speed and load. Modifications to fuel system components may be required to avoid engine derate.

References

References
1.
Bridgwater
,
A. V.
,
1995
, “
The Technical and Economic Feasibility of Biomass Gasification for Power Generation
,”
Fuel
,
74
(
5
), pp.
631
653
.
2.
Leiker
,
M.
,
Cartellieri
,
W.
,
Christoph
,
K.
,
Pfeifer
,
U.
, and
Rankl
,
M.
,
1972
, “
Evaluation of Antiknocking Property of Gaseous Fuels by Means of Methane Number and Its Practical Application to Gas Engines
,”
ASME
Paper No. 72-DGP-4.
3.
Choquette
,
G.
,
2014
, “
Analysis and Estimation of Stoichiometric Air/Fuel Ratio and Methane Number for Gas
,” Gas Machinery Research Council (GMRC) Meeting, Nashville, TN, Oct. 5–8, 2014.
4.
Xu
,
H.
, and
LaPointe
,
L. A.
,
2014
, “
Combustion Characteristics of Lean Burn and Stoichiometric With EGR Spark Ignited Natural Gas Engines
,”
ASME
Paper No. ICEF2014-5521.
5.
Xu
,
H.
, and
LaPointe
,
L. A.
,
2013
, “
Calculation of Laminar Flame Speed and Autoignition Delay at High Temperature and Pressures
,”
ASME
Paper No. ICEF 2013-19028.
6.
Livengood
,
J. C.
, and
Wu
,
P. C.
,
1955
, “
Correlation of Autoignition Phenomena in Internal Combustion Engines and Rapid Compression Machines
,”
Symp. (Int.) Combust.
,
5
(
1
), pp.
347
356
.
You do not currently have access to this content.