scholarly journals Influence of Gasification Operating Parameters on Performance of the Nong Bua Dual Fluidized Bed Gasification System in Thailand

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Vilailuck Siriwongrungson ◽  
Malinee Prasong ◽  
Janjira Hongrapipat ◽  
Reinhard Rauch ◽  
Shusheng Pang ◽  
...  
Keyword(s):  
System Performance ◽  
Operating Time ◽  
Gas Composition ◽  
Heating Value ◽  
Product Gas ◽  
Lower Heating Value ◽  
Dual Fluidized Bed ◽  
Bed Material ◽  
System Power ◽  
Lower Heating

Gasification system performance generally depends on feed moisture content, activity of bed material, gasifier and combustor temperatures, and scrubber media. The tar concentration and gas composition of product gas are two indicators of the gasification system performance. In this research, the effects of gasifier temperature and the activity of bed material on the tar concentration and gas composition of the product gas produced from a dual fluidized bed (DFB) gasification system power plant were investigated. The DFB gasification system power plant is located in Nong Bua district, Nakhon Sawan province, Thailand. Two periods of gasification operation were examined. These two periods were when the olivine was freshy activated and then after a period of operation. The gasifier temperature had several peaks during the operation, which caused the product gas composition to fluctuate. When the olivine had been used for a period, the percentage of hydrogen was approximately 3% higher than when the olivine had been freshly activated, and a lower heating value was observed, which was probably due to lower heating value of hydrogen. The tar concentration was substantially lower when compared with the freshly activated olivine. When the olivine was used for a period, the average tar concentration was 56±22 mg/Nm3 (this is after 95 h continuous operating time) while the average tar concentration of the freshly activate olivine was 872±125 mg/Nm3 (which was after 34.5 h continuous operating time). It was concluded that the average tar concentration and gas composition were influenced by the activity of the bed material and the gasification temperature.

Herb Residues Gasification in a Circulating Fluidized Bed

2012 ◽  
Vol 549 ◽  
pp. 508-512 ◽  
Author(s):  
Fei Qiang Guo ◽  
Yu Ping Dong
Keyword(s):  
Fluidized Bed ◽  
Circulating Fluidized Bed ◽  
Good Condition ◽  
Gas Composition ◽  
Heating Value ◽  
Product Gas ◽  
Lower Heating Value ◽  
Gas Fuel ◽  
Herb Residues ◽  
Lower Heating

A circulating utilization way of herb residues is designed to convert herb residues to gas fuel in industrial-scale by a circulating gasification bed gasifier in this work. The gasification characteristics of herb residues in the circulating fluidized bed of 300kg/h were investigated in about 200 hours. The results indicated that the gas composition and tar yield were affected by oxygen to biomass ratio (O/B ratio). The lower heating value of product gas was 4 to 5MJ/m3 using herb residues as feedstock. When O/B was 0.37, the product gas reached a good condition with lower heating value of 4.89MJ/m3.

scholarly journals Experimental Gasification of Biomass in an Updraft Gasifier with External Recirculation of Pyrolysis Gases

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Adi Surjosatyo ◽  
Fajri Vidian ◽  
Yulianto Sulistyo Nugroho
Keyword(s):  
Combustion Zone ◽  
Air Flow ◽  
Simple Type ◽  
Gas Composition ◽  
Reduction Zone ◽  
Heating Value ◽  
High Conversion Efficiency ◽  
Lower Heating Value ◽  
Pyrolysis Gases ◽  
Lower Heating

The updraft gasifier is a simple type of reactor for the gasification of biomass that is easy to operate and has high conversion efficiency, although it produces high levels of tar. This study attempts to observe the performance of a modified updraft gasifier. A modified updraft gasifier that recirculates the pyrolysis gases from drying zone back to the combustion zone and gas outlet at reduction zone was used. In this study, the level of pyrolysis gases that returned to the combustion zone was varied, and as well as measurements of gas composition, lower heating value and tar content. The results showed that an increase in the amount of pyrolysis gases that returned to the combustion zone resulted in a decrease in the amount of tar produced. An increase in the amount of recirculated gases tended to increase the concentrations of H2and CH4and reduce the concentration of CO with the primary (gasification) air flow held constant. Increasing the primary air flow tended to increase the amount of CO and decrease the amount of H2. The maximum of lower heating value was 4.9 MJ/m3.

scholarly journals Effect of biomass fuel ash and bed material on the product gas composition in DFB steam gasification

Energy ◽  
2021 ◽  
Vol 219 ◽  
pp. 119650
Author(s):  
K. Fürsatz ◽  
J. Fuchs ◽  
F. Benedikt ◽  
M. Kuba ◽  
H. Hofbauer
Keyword(s):  
Steam Gasification ◽  
Biomass Fuel ◽  
Gas Composition ◽  
Product Gas ◽  
Fuel Ash ◽  
Bed Material

scholarly journals Combustion Study of Polyoxymethylene Dimethyl Ethers and Diesel Blend Fuels on an Optical Engine

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4608
Author(s):  
Jingjing He ◽  
Hao Chen ◽  
Xin Su ◽  
Bin Xie ◽  
Quanwei Li
Keyword(s):  
Soot Formation ◽  
Comprehensive Evaluation ◽  
Chemical Properties ◽  
Heating Value ◽  
Optical Engine ◽  
Leading Role ◽  
Combustion Duration ◽  
Polyoxymethylene Dimethyl Ethers ◽  
Lower Heating Value ◽  
Lower Heating

Polyoxymethylene dimethyl ethers (PODE) are a newly appeared promising oxygenated alternative that can greatly reduce soot emissions of diesel engines. The combustion characteristics of the PODE and diesel blends (the blending ratios of PODE are 0%, 20%, 50% and 100% by volume, respectively) are investigated based on an optical engine under the injection timings of 6, 9, 12 and 15-degree crank angles before top dead center and injection pressures of 100 MPa, 120 MPa and 140 MPa in this study. The results show that both the ignition delay and combustion duration of the fuels decrease with the increasing of PODE ratio in the blends. However, in the case of the fuel supply of the optical engine being fixed, the heat release rate, cylinder pressure and temperature of the blend fuels decrease with the PODE addition due to the low lower heating value of PODE. The addition of PODE in diesel can significantly reduce the integrated natural flame luminosity and the soot formation under all injection conditions. When the proportion of the PODE addition is 50% and 100%, the chemical properties of the blends play a leading role in soot formation, while the change of the injection conditions have an inconspicuous effect on it. When the proportion of the PODE addition is 20%, the blend shows excellent characteristics in a comprehensive evaluation of combustion and soot reduction.

Biodiesel Effects on Influencing Parameters of Brake Fuel Conversion Efficiency in a Medium Duty Diesel Engine

2010 ◽  
Vol 132 (12) ◽  
Author(s):  
Joshua A. Bittle ◽  
Jesse K. Younger ◽  
Timothy J. Jacobs
Keyword(s):  
Conversion Efficiency ◽  
Energy Content ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Biodiesel Fuel ◽  
Mass Energy ◽  
Fuel Conversion ◽  
Heating Value ◽  
Lower Heating Value ◽  
Lower Heating

Biodiesel remains an alternative fuel of interest for use in diesel engines. A common characteristic of biodiesel, relative to petroleum diesel, is a lowered heating value (or per mass energy content of the fuel). For same torque engine comparisons, the lower heating value translates into a higher brake specific fuel consumption (amount of fuel consumed per unit of power produced). The efficiency at which fuel energy converts into work energy, however, may remain unchanged. In this experimental study, evaluating nine unique engine operating conditions, the brake fuel conversion efficiency (an assessor of fuel energy to work energy efficiency) remains unchanged between 100% petroleum diesel fuel and 100% biodiesel fuel (palm olein) at all conditions, except for high load conditions. Several parameters may affect the brake fuel conversion efficiency, including heat loss, mixture properties, pumping work, friction, combustion efficiency, and combustion timing. This article describes a study that evaluates how the aforementioned parameters may change with the use of biodiesel and petroleum diesel, and how these parameters may result in differences in the brake fuel conversion efficiency.

scholarly journals Lower Heating Value of Jet Fuel from Hydrocarbon Class Concentration Data and Thermo-Chemical Reference Data: An Uncertainty Quantification

2021 ◽  
Author(s):  
Randall Boehm ◽  
Zhibin Yang ◽  
David Bell ◽  
John Feldhausen ◽  
Joshua Heyne
Keyword(s):  
Jet Fuel ◽  
Confidence Bands ◽  
Heats Of Formation ◽  
Concentration Data ◽  
Heating Value ◽  
Accuracy And Precision ◽  
Lower Heating Value ◽  
Detailed Assessment ◽  
Value Net ◽  
Lower Heating

A detailed assessment is presented on the calculation and uncertainty of the lower heating value (net heat of combustion) of conventional and sustainable aviation fuels, from hydrocarbon class concentration measurements, reference molecular heats of formation, and the uncertainties of these reference heats of formation. Calculations using this paper’s method and estimations using ASTM D3338 are reported for 17 fuels of diverse compositions and compared against reported ASTM D4809 measurements. All the calculations made by this method and the reported ASTM D4809 measurements agree (i.e., within 95% confidence intervals). The 95% confidence interval of the lower heating value of fuel candidates that are comprised entirely of normal- and iso-alkanes is less than 0.1 MJ/kg by the method described here, while high cyclo-alkane content leads to 95% confidence bands that approach 0.2 MJ/kg. Taking a possible bias into account, the accuracy and precision of the method described in this work could be as high as 0.23 MJ/kg for some samples.

scholarly journals The Technological Investigations Of Manufacturing Of Energy Chips

2015 ◽  
Vol 1 ◽  
pp. 220
Author(s):  
Ziedonis Miklašēvičs
Keyword(s):  
Moisture Content ◽  
Dry Mass ◽  
Quality Parameters ◽  
Heating Value ◽  
Long Term Storage ◽  
Lower Heating Value ◽  
Term Storage ◽  
Lower Heating

The methodology in Latvia forest industry provide to determine the quality of energy chips only in long- term storage places before selling. Due to the lack of hard empirical data about the quality parameters of energy chips in different phases of manufacturing process, this research paper consists of: - the identification and analyses of the factors that influenced the values of energy chips quality features such as: bulk density, moisture content, ash content, higher and lower heating value according to actual moisture content and per dry mass of the chips; - the methodology for determination the quality parameters of energy chips by analysis the wood moisture content and by choice the method of the manufacturing of energy chips.

scholarly journals EXERGY-BASED INVESTIGATION OF A COAL-FIRED ALLAM CYCLE

2019 ◽  
Vol 137 ◽  
pp. 01018 ◽  
Author(s):  
Jing Luo ◽  
Ogechi Emelogu ◽  
Tatiana Morosuk ◽  
George Tsatsaronis
Keyword(s):  
Fossil Fuels ◽  
Coal Gasification ◽  
High Efficiency ◽  
Cycle Performance ◽  
Energetic Efficiency ◽  
Component Level ◽  
Lower Efficiency ◽  
Heating Value ◽  
Lower Heating Value ◽  
Lower Heating

Allam cycle is a novel cycle that capitalizes on the unique thermodynamic properties of supercritical CO2 and the advantages of oxy-combustion for power generation. It is a high-pressure supercritical carbon dioxide cycle designed to combust fossil fuels such as natural gas or syngas (from coal gasification systems) with complete CO2 separation at a high-efficiency and zero atmospheric emissions. This semi-closed cycle produces sequestration-ready/pipeline quality CO2 by-product, and thus eliminates the need for additional CO2-capture system. The Coal-fueled Allam cycle is targeted to deliver between 51-52% net efficiency (lower heating value) for coal gasification. In this study, the expected energetic efficiency is verified by simulating the system in Ebsilon professional software and the result showed that the net efficiency of the simulated coal-fired plant is 30.7%, which is significantly lower than the targeted value. The lower efficiency maybe as a result of the missing heat integration in the system, the high power demand of the oxidant compressor and CO2 compressors. And an exergy analysis based on published cycle data is employed, to investigate the cycle performance, identify the sources of the cycle’s thermodynamic inefficiencies at the component level; a sensitivity analysis is also performed to study the effects of selected thermodynamic parameters on the overall performance of the coal-fired Allam cycle.

Industrial Process Description for the Recovery of Agricultural Water From Digestate

2020 ◽  
Vol 142 (7) ◽  
Author(s):  
Halina Pawlak-Kruczek ◽  
Agnieszka Urbanowska ◽  
Weihong Yang ◽  
Gerrit Brem ◽  
Aneta Magdziarz ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Rural Areas ◽  
Reclaimed Water ◽  
Industrial Process ◽  
Hydrothermal Carbonization ◽  
Full Potential ◽  
Agricultural Water ◽  
Heating Value ◽  
Lower Heating Value ◽  
Lower Heating

Abstract Currently, the reclamation and reuse of water have not reached their full potential, although more energy is needed to obtain and transport freshwater and this solution has a more serious environmental impact. Agricultural irrigation is, by far, the largest application of reclaimed water worldwide, so the proposed concept may result in the production of water that can be used, among others, for crop irrigation. This paper describes a novel installation for the recovery of the agricultural water from the digestate, along with the results of initial experiments. Currently, water is wasted, due to evaporation, in anaerobic digestion plants, as the effluent from dewatering of the digestate is discharged into lagoons. Moreover, water that stays within the interstitial space of the digestate is lost in a similar fashion. With increasing scarcity of water in rural areas, such waste should not be neglected. The study indicates that hydrothermal carbonization (HTC) enhances mechanical dewatering of the agricultural digestate and approximately 900 L of water can be recovered from one ton. Dewatered hydrochars had a lower heating value of almost 10 MJ/kg, indicating the possibility of using it as a fuel for the process. The aim of this Design Innovation Paper is to outline the newly developed concept of an installation that could enable recovery of water from, so far, the neglected resource—i.e., digestate from anaerobic digestion plants.

The Ethanol-Water Humidification Process in EvGT Cycles

2004 ◽  
Author(s):  
Marcus Thern ◽  
Torbjo¨rn Lindquist ◽  
Tord Torisson
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Production ◽  
Test Facility ◽  
Level Energy ◽  
Water Mixture ◽  
Evaporation Process ◽  
Heating Value ◽  
Lower Heating Value ◽  
Lower Heating

Ethanol from bio-products has become an important fuel for future power production. However, the present production technology is rather expensive. This paper focuses on how to lower the production cost of ethanol extraction from mash, and to use the ethanol as a primary fuel in gas turbines for heat and power production. Today, ethanol is produced during distillation by supplying energy to extract the ethanol from the mash. Using the evaporation process in the evaporative gas turbine to extract the ethanol from the mash before the distillation step, a lot of energy can be saved. In the evaporation process, the ethanol is extracted directly from the mash using energy from low-level energy sources. The evaporation technology is therefore expected to reduce the cost for the ethanol production. Simultaneous heat and mass transfer inside the ethanol humidification tower drives a mixture of ethanol and water into the compressor discharge air. To investigate the evaporation of a binary mixture into air at elevated pressures and temperatures, a test facility was constructed and integrated into the evaporative gas turbine pilot-plant. The concentration of ethanol in the mash is not constant but depends on the sugar content in the feedstock used in the fermentation process. Tests were therefore conducted at different concentrations of ethanol in the ethanol-water mixture. Tests were also performed at different temperature and flow conditions to establish the influence of these parameters on the lower heating value of the produced low calorific gas. It has been shown that this technology extracts about 80% of the ethanol from the mash. It has also been shown that the composition of the resulting gas depends on the temperatures, flow rates and composition of the incoming streams. The tests have shown that the produced gas has a lower heating value between of 1.8 to 3.8 MJ/kg. The produced gas with heating values in the upper range is possible to use as fuel in the gas turbine without any pilot flame. Initial models of the ethanol humidification process have been established and the initial test results have been used for validating developed models.

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