Landfill Gas Fueled HCCI Demonstration System

A demonstration system has been developed intending to meet the California Energy Commission’s primary goal of improving California’s electric energy cost/value by providing a low-cost, high-efficiency distributed power generation system that operates on landfill gas as fuel. The project team led by Makel Engineering, Inc. includes UC Berkeley, CSU Chico and the Butte County Public Works Department. The team has developed a reliable, multi-cylinder Homogeneous Charge Compression Ignition (HCCI) engine by converting a Caterpillar 3116, 6.6 liter diesel engine to operate in HCCI mode. This engine utilizes a simple and robust thermal control system. Typically, HCCI engines are based on standard diesel engine designs with reduced complexity and cost based on the well known principles of engine dynamics. Coupled to an induction generator, this HCCI genset allows for simplified power grid connection. Testing with this HCCI genset allowed for the development of a control system to maintain optimal the inlet temperature and equivalence ratio. A brake thermal efficiency of 35.0% was achieved while producing less than 10.0 ppm of NOx and 30 kW of electrical power. Less than 5.0 ppm of NOx was recorded with a slightly lower brake thermal efficiency. Tests were conducted with both natural gas and simulated landfill gas as a fuel source. This demonstration system has shown that landfill gas fueled Homogeneous Charge Compression Ignition engine technology is a viable technology for distributed power generation.

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Decreasing hydrocarbon and carbon monoxide emissions of a natural-gas engine operating in the quasi-homogeneous charge compression ignition mode at low loads

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/095440705x34793 ◽

2005 ◽

Vol 219 (9) ◽

pp. 1125-1131 ◽

Cited By ~ 5

Author(s):

Su Ling ◽

Zhou Longbao ◽

Liu Shenghua ◽

Zhong Hui

Keyword(s):

Carbon Monoxide ◽

Natural Gas ◽

Thermal Efficiency ◽

Homogeneous Charge Compression Ignition ◽

Compression Ignition ◽

Brake Thermal Efficiency ◽

Pilot Fuel ◽

Cng Engine ◽

Standard Mode ◽

Homogeneous Charge

Experimental studies have been carried out on decreasing the hydrocarbon (HC) and carbon monoxide (CO) emissions of a compressed natural-gas (CNG) engine operating in quasi-homogeneous charge compression ignition (QHCCI) mode at low loads. The effects of three technical approaches including partial gas cut-off (PGC), intake air throttling, and increasing the pilot fuel quantity on emissions and the brake thermal efficiency of the CNG engine are studied. The results show that HC and CO emissions can be reduced with only a small penalty on the brake thermal efficiency. An increase in the brake thermal efficiency and reductions in HC and CO emissions can be simultaneously realized by increasing the pilot fuel quantity. It is also indicated from experiments that the HC and CO emissions of the engine can be effectively reduced when using intake air throttling and increasing the pilot fuel quantity are both adopted. However, nitrogen oxide (NOx) emissions increase with increase in the throttling and the pilot fuel quantity. Under PGC conditions, NOx emissions are lower than those in the standard mode; however, they increase and exceed the values in the standard mode in increases in the load and natural-gas supply.

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Development of an exhaust gas recirculation strategy for an acetylene-fuelled homogeneous charge compression ignition engine

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/09544070jauto1364 ◽

2010 ◽

Vol 224 (7) ◽

pp. 941-952 ◽

Cited By ~ 7

Author(s):

K Sudheesh ◽

J M Mallikarjuna

Keyword(s):

Thermal Efficiency ◽

Homogeneous Charge Compression Ignition ◽

Exhaust Gas Recirculation ◽

Electrical Heating ◽

Exhaust Gas ◽

Compression Ignition ◽

Brake Thermal Efficiency ◽

Load Limit ◽

Gas Recirculation ◽

Load Conditions

This paper deals with experimental investigations carried out to develop an exhaust gas recirculation (EGR) strategy for an acetylene-fuelled homogeneous charge compression ignition (HCCI) engine. This study involves an analysis of the external inlet charge heating, the use of a mix of hot EGR and cool EGR to extend the load range, and the performance of the engine in the acetylene HCCI mode. First, experiments are conducted on a single-cylinder engine in the acetylene HCCI mode with external electrical heating at different load conditions, and the best inlet charge temperatures at each load condition are obtained. Second, hot EGR or a mix of hot EGR and cool EGR (i.e. the EGR strategy) is used to reduce or eliminate external charge heating and to extend the upper load limit, or to improve the brake thermal efficiency. In both cases, the engine performance is compared with that of the conventional diesel compression ignition (CI) mode. It is found that with EGR, above 25 per cent of load, the upper load limit at different inlet charge temperatures increases by about 16 28 per cent without any external charge heating. Below 25 per cent of load, the electrical heating at different inlet charge conditions is reduced by about 67–87 per cent. The brake thermal efficiency increases by 5–24 per cent under all the load conditions and it is comparable with that in the conventional CI mode. In the HCCI mode, nitrogen oxide levels are less than 20ppm. Smoke levels are always lower than 0.1 Bosch smoke unit. Hydrocarbon and carbon monoxide emissions are relatively higher than for the conventional CI mode.

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Thermodynamic analysis and comparison of downdraft gasifiers integrated with gas turbine, spark and compression ignition engines for distributed power generation

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2014.02.027 ◽

2014 ◽

Vol 66 (1-2) ◽

pp. 290-297 ◽

Cited By ~ 12

Author(s):

Andrés Z. Mendiburu ◽

Justo J. Roberts ◽

João A. Carvalho ◽

José L. Silveira

Keyword(s):

Power Generation ◽

Gas Turbine ◽

Thermodynamic Analysis ◽

Compression Ignition ◽

Distributed Power ◽

Distributed Power Generation ◽

Compression Ignition Engines

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Effect of Load Level on the Performance of a Dual Fuel Compression Ignition Engine Operating on Syngas Fuels With Varying H2/CO Content

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4003956 ◽

2011 ◽

Vol 133 (12) ◽

Cited By ~ 16

Author(s):

B. B. Sahoo ◽

U. K. Saha ◽

N. Sahoo

Keyword(s):

Diesel Engine ◽

Thermal Efficiency ◽

Peak Pressure ◽

Gaseous Fuel ◽

Dual Fuel ◽

Engine Fuel ◽

Compression Ignition ◽

Compression Ignition Engine ◽

Engine Operation ◽

Brake Thermal Efficiency

Syngas, an environmentally friendly alternative gaseous fuel for internal combustion engine operation, mainly consists of carbon monoxide (CO) and hydrogen (H2). It can substitute fossil diesel oil in a compression ignition diesel engine through dual fuel operation route. In the present investigation, experiments were conducted in a constant speed single cylinder direct injection diesel engine fuelled with syngas-diesel in a dual fuel operation mode. The main contribution of this study is to introduce the new synthetic gaseous fuel (syngas) including the possible use of CO gas, an alternative diesel engine fuel. In this work, four different H2 and CO compositions of syngas were chosen for dual fuel study under different engine loading levels. Keeping the same power output at the corresponding tested loads, the engine performance of dual fuel operations were compared to that of diesel mode for the entire load range. The maximum diesel replacement in the engine was found to be 72.3% for 100% H2 fuel. This amount replacement rate was reduced for the low energetic lower H2 content fuels. The brake thermal efficiency was always found highest (about 21%) in the case of diesel mode operation. However, the 100% H2 syngas showed a comparative performance level with diesel mode at the expense of higher NOx emissions. At 80% engine load, the brake thermal efficiency was found to be 15.7% for 100% CO syngas. This value increased to 16.1%, 18.3% and 19.8% when the 100% CO syngas composition was replaced by H2 contents of 50%, 75% and 100%, respectively. At part loads (i.e., at 20% and 40%), dual fuel mode resulted a poor performance including higher emission levels. In contrast, at higher loads, syngas fuels showed a good competitive performance to diesel mode. At all the tested loads, the NOx emission was observed highest for 100% H2 syngas as compared to other fuel conditions, and a maximum of 240 ppm was found at 100% load. However, when the CO fractions of 25%, 50% and 100%, were substituted to hydrogen fuel, the emission levels got reduced to 175 ppm, 127 ppm, and 114 ppm, respectively. Further, higher CO and HC emission levels were recorded for 25%, 50%, and 100% CO fraction syngas fuels due to their CO content. Ignition delay was found to increase for the dual fuel operation as compared to diesel mode, and also it seemed to be still longer for higher H2 content syngas fuels. The peak pressure and maximum rate of pressure rise were found to decrease for all the cases of dual fuel operation, except for 100% H2 syngas (beyond 60% load). The reduction in peak pressure resulted a rise in the exhaust gas temperature at all loads under dual fuel operation. The present investigation provides some useful experimental data which can be applied to the possible existing engine parameters modifications to produce a competitive syngas dual fuel performance at all the loading operations.

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Micro Humid Air Cycle: Part A — Thermodynamic and Technical Aspects

Volume 3: Turbo Expo 2003 ◽

10.1115/gt2003-38326 ◽

2003 ◽

Cited By ~ 25

Author(s):

J. Parente ◽

A. Traverso ◽

A. F. Massardo

Keyword(s):

Power Generation ◽

Thermal Efficiency ◽

Specific Work ◽

Humid Air ◽

Distributed Power ◽

Analysis And Design ◽

Distributed Power Generation ◽

Air Turbine ◽

Work Up ◽

Energy Plants

With the increasing interest in distributed power and heat generation, microturbines (mGT) have come to play an important role in small-size energy plants as the most competitive alternative to piston engines, due to their low environmental impact and reduced O&M costs. The Humid Air Turbine (HAT), which has received special attention over the last ten years, can be exploited to enhance thermal efficiency for power generation, although it is still not able to provide more than 30% efficiency for a regenerated cycle. For this reason a micro HAT cycle seems to offer an interesting way to significantly increase thermal efficiency and specific work and easily reduce NOx emissions. This paper presents a general thermodynamic assessment of a micro Humid Air cycle (mHAT), in the range of 100–500 kWe, with cycle optimisation, and a preliminary attempt to integrate existing microturbines and the humid air cycle: the results show that a remarkable increase in efficiency (up to 3–5 percentage points) and specific work (up to 50–70%) can be achieved without any major re-design of the machine, with the exception of the combustion chamber. Moreover, the detailed analysis and design of the saturation tower demonstrates its compactness, one of the overriding requirements for a system for distributed power generation.

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