Japanese utilities put fuel mixing at center of decarbonization strategy

2021 ◽  
Vol 46 (10) ◽  
pp. 7-8
Keyword(s):  
Fuel Mixing

Dual-Location Fuel Injection Effects on Emissions and NO*/OH* Chemiluminescence in a High Intensity Combustor

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Ahmed O. Said ◽  
Ahmed E. E. Khalil ◽  
Ashwani K. Gupta
Keyword(s):  
Fuel Injection ◽  
Single Injection ◽  
Mixing Time ◽  
Fuel Mixture ◽  
Combustion Noise ◽  
Fuel Distribution ◽  
Mixture Preparation ◽  
Pollutants Emission ◽  
Fuel Mixing ◽  
Colorless Distributed Combustion

Colorless distributed combustion (CDC) has shown to provide ultra-low emissions of NO, CO, unburned hydrocarbons, and soot, with stable combustion without using any flame stabilizer. The benefits of CDC also include uniform thermal field in the entire combustion space and low combustion noise. One of the critical aspects in distributed combustion is fuel mixture preparation prior to mixture ignition. In an effort to improve fuel mixing and distribution, several schemes have been explored that includes premixed, nonpremixed, and partially premixed. In this paper, the effect of dual-location fuel injection is examined as opposed to single fuel injection into the combustor. Fuel distribution between different injection points was varied with the focus on reaction distribution and pollutants emission. The investigations were performed at different equivalence ratios (0.6–0.8), and the fuel distribution in each case was varied while maintaining constant overall thermal load. The results obtained with multi-injection of fuel using a model combustor showed lower emissions as compared to single injection of fuel using methane as the fuel under favorable fuel distribution condition. The NO emission from double injection as compared to single injection showed a reduction of 28%, 24%, and 13% at equivalence ratio of 0.6, 0.7, and 0.8, respectively. This is attributed to enhanced mixture preparation prior to the mixture ignition. OH* chemiluminescence intensity distribution within the combustor showed that under favorable fuel injection condition, the reaction zone shifted downstream, allowing for longer fuel mixing time prior to ignition. This longer mixing time resulted in better mixture preparation and lower emissions. The OH* chemiluminescence signals also revealed enhanced OH* distribution with fuel introduced through two injectors.

scholarly journals Nitrogen Oxide Reduction by Staged Combustion of Biomass Gas in Gas Turbines — A Modeling Study of the Effect of Mixing

1999 ◽  
Author(s):  
Edgardo G. Coda Zabetta ◽  
Pia T. Kilpinen ◽  
Mikko M. Hupa ◽  
Jukka K. Leppälahti ◽  
C. Krister O. Ståhl ◽  
...  
Keyword(s):  
Gas Turbines ◽  
Nox Reduction ◽  
Plug Flow ◽  
Chemical Kinetic ◽  
Process Variables ◽  
Staged Combustion ◽  
Fuel Gas ◽  
Effective Option ◽  
Fuel Mixing ◽  
Lower Temperature

Detailed chemical kinetic modeling has been used to study the reduction of nitrogen oxides at gas turbine (GT) combustor conditions. A gas from gasification of wood with air has been used as the fuel. An air-staged combustion technique has been adapted. In our previous study a simple plug flow model was used to study the effects of pressure and temperature among others process variables. The air-fuel mixing was assumed perfect and instantaneous. Results showed the NOx reduction mainly affected by both pressure and temperature. The aim of the present work is to establish the effect of air-fuel mixing delay on NOx predictions and to extrapolate indications options for GT. To model the mixing delay, a varying number of air sub-streams are mixed with the fuel gas during different time periods. Alternatively, a combination of a perfectly mixed zone followed by a plug flow zone is illustrated. Results by any air-fuel mixing model show similar affect of process variables on NOx reduction. When a mixing delay is assumed instead of the instantaneous mixing the NOx reduction is enhanced, and only with delayed mixing NOx are affected by CH4. Lower temperature and higher pressure in the GT-combustor can enhance the NOx reduction. Also air staging is an effective option: a 3 stages combustor designed for low mixing speed appear competitive compared to more complicate combustors. The fewer hydrocarbons in the gasification gas the high NOx reduction.

scholarly journals KARAKTERISTIK BIO-OIL HASIL PIROLISIS LIMBAH BREM DENGAN VARIASI TEMPERATUR

2019 ◽  
Vol 7 (1) ◽  
pp. 23-28
Author(s):  
Edi Munarwan
Keyword(s):  
High Temperature ◽  
Temperature Variation ◽  
Fossil Fuel ◽  
Trial Result ◽  
Flash Point ◽  
Burning Process ◽  
Automotive Technology ◽  
Bio Oil ◽  
Fuel Mixing ◽  
Optimal Mixing

Abstract             The increasing number of automotive technology and vehicle cause using fossil fuel also rises. So it is needed alternative fuel as replacement or mixing of  the fuel, for keeping the existence so that the crisis of fuel will not happen. Bio-oil is a product resulted from pyrolisis which can be used as solar fuel mixing. Bio-oil is a obtained from brem waste which is processed with pyrolisis technique. Pyrolisis is a substance burning process in high temperature without using oxygen. In this research is using 250oC, 350oC, 450oC and 550oC temperature variation which need 3 hours of time and mass 500 grams. The Bio-oil which is produced by pyrolisis is combined by solar and tested to determine the characteristic. The first trial is done to earn the volume pyrolisis result from each temperature. The second trial uses ASTM D 445-12 method to earn viscosity in 40oC temperature and ASTM D 93-12 method to get flash point. The result of the trial shows the highest volume is earned from 5500C temperature which produce bio-oil around 254 ml. The trial result of 5% bio-oil combination from every temperature is earned the best result from 450oC temperature, while the optimal mixing percentage bio-oil with solar is earned the highest viscosity inmixture of 15% bio-oil which 85% solar around 4,779 mm2/s and the highest flash point is earned from mixture of 5% bio-oil which 95% solar around 61oC. Keywords : bio-oil, pyrolysis, flash point, viscosity   AbstrakPeningkatan teknologi otomotif dan jumlah kendaraan yang meningkat menyebabkan penggunaan bahan bakar fosil semakin meningkat. Maka  dibutuhkan bakan bakar alternatif sebagai pengganti atau campuran bahan bakar, untuk menjaga agar tidak terjadi krisis bahan bakar. Bio-oil merupakan salah satu produk hasil pirolisis yang dapat digunakan sebagai campuran bahan bakar solar. Bio-oil diperoleh dari limbah brem yang diproses dengan cara  pirolisis. Pirolisis merupakan proses pembakaran suatu bahan pada suhu tinggi tanpa oksigen. Pada penelitian ini menggunakan variasi temperatur 250oC, 350oC, 450oC dan 550oC dengan waktu 3 jam dan massa 500 gram. Bio-oil hasil pirolisis divariasikan dengan solar dan diuji untuk mengetahui karakteristiknya. Pengujian pertama dilakukan untuk mendapatkan volume hasil pirolisis dari tiap temperatur. Pengujian kedua menggunakan metode ASTM D 445-12 untuk mendapatkan viskositas pada suhu 40oC dan metode ASTM D 93-12 untuk mendapatkan titik nyala. Hasil pengujian menunjukkan volume tertinggi diperoleh dari temperatur 5500C menghasilkan bio-oil sebanyak 254 ml. Hasil pengujian variasi campuran 5% bio-oil dari tiap temperatur diperoleh hasil yang terbaik yaitu dari temperatur 4500C, sedangkan persentase campuran yang optimal bio-oil dengan solar diperoleh viskositas tertinggi pada campuran 15% bio-oil dengan 85% solar sebesar 4,779 mm2/s dan titik nyala tertinggi diperoleh dari campuran 5% bio-oil dengan 95% solar sebesar 61oC Kata Kunci: : bio-oil, pirolisis, titik nyala,  viskositas

Development of a calibrated technique forin situinvestigation of air–fuel mixing in engines

2006 ◽  
Vol 54 (1) ◽  
pp. 33-45
Author(s):  
G de Sercey ◽  
G Awcock ◽  
M Heikal
Keyword(s):  
Fuel Mixing

Medium and High Load Performance of Partially Premixed Combustion in a Wave-Piston Multi-Cylinder Engine With Diesel and PRF70 Fuel

2018 ◽  
Author(s):  
Kenan Muric ◽  
Per Tunestal ◽  
Ingemar Magnusson
Keyword(s):  
Heat Transfer ◽  
High Load ◽  
Single Stage ◽  
Premixed Combustion ◽  
Nox Emissions ◽  
Heavy Duty ◽  
Partially Premixed Combustion ◽  
Fuel Mixing ◽  
Partially Premixed ◽  
Soot Emissions

European and US emission legislation on diesel compression ignition engines has pushed for the development of new types of combustion concepts to reduce hazardous pollutants and increase fuel efficiency. Partially premixed combustion (PPC) has been proposed as one solution to future restrictions on emissions while providing high gross indicated efficiency. The conceptual idea is that the time for the mixing between fuel and air will be longer when ignition delay is increased by addition of high amounts of exhaust gas recirculation (EGR). Increased air-fuel mixing time will lead to lower soot emissions and the high EGR rates will reduce both NOx emissions and combustion flame temperature, which decreases the overall heat transfer. Previous research in heavy-duty gasoline PPC has mostly focused on emissions and efficiency at low and medium load in single-cylinder engines. In this paper a Volvo D13 heavy-duty single-stage VGT engine with a newly developed Wave piston was run at medium and high engine load with a variation in fuel injection pressure. The Wave piston was specifically designed to enhance air-fuel mixing and increase combustion velocity. Two fuels were used in the experiments, PRF70 and Swedish MK1 diesel. Soot-NOx trade-off, combustion characteristics and efficiency were compared for both fuels at 1000 and 2000 Nm engine torque. The results show that at high load the combustion behavior with respect to rate of heat release and heat transfer is very similar between the fuels and no major difference in indicated efficiency could be observed. Peak gross indicated efficiencies were reported to be around 49 % for both fuels at 1000 Nm and slightly above 50 % at 2000 Nm. The new Wave piston made it possible to obtain 1 g/kWh engine-out NOx emissions while still complying with Euro VI legislation for particulate emissions. Soot emissions were generally lower for PRF70 compared to MK1 diesel. We could also conclude that gas exchange performance is a major issue when running high load PPC where high Λ and EGR is required. The single-stage VGT turbocharger could not provide sufficient boost to keep Λ above 1.3 at high EGR rates. This penalized combustion efficiency and soot emissions when reaching Euro VI NOx emission levels (0.3–0.5 g/kWh).

Sign in / Sign up

Export Citation Format

Share Document