scholarly journals Performance Analysis of the Prosopis Juliflora wood Based 10 kWe Downdraft Gasifier

2017 ◽  
Vol 13 (8) ◽  
pp. 6385-6388
Author(s):  
SIVA KUMAR

Gasification of solid biomass into gas often referred as producer gas which has higher heating value can be used to operate internal combustion engine. Here  an attempt has been made to  successful gasification of Prosopis Juliflora Wood and identification of optimum equivalence ratios in downdraft double throat gasifier for generation of quality gas for onward generation of power. A small scale downdraft double throat wood gasifier is designed to deliver a power of 10 kWe to run an IC Engine also the the performance analysis like Specific gasification rate , Gas production rate,gas efficiency,fuel consumption rate are prdedicted for given conditions.The optimum equivalence ratio for  wood have been estimated to 0.3, the gas composition( CO,H2) and calorific value of  wood is  observed as  CO = 18.8 %,H2 =12.8 %,CV =1042 Kcal/nm3 .

2016 ◽  
Vol 35 (3) ◽  
pp. 276-284 ◽  
Author(s):  
Sunil L Narnaware ◽  
NSL Srivastava ◽  
Samir Vahora

Vegetables waste is generally utilized through a bioconversion process or disposed of at municipal landfills, dumping sites or dumped on open land, emitting a foul odor and causing health hazards. The presents study deals with an alternative way to utilize solid vegetable waste through a thermochemical route such as briquetting and gasification for its energy recovery and subsequent power generation. Briquettes of 50 mm diameter were produced from four different types of vegetable waste. The bulk density of briquettes produced was increased 10 to 15 times higher than the density of the dried vegetable waste in loose form. The lower heating value (LHV) of the briquettes ranged from 10.26 MJ kg−1 to 16.60 MJ kg−1 depending on the type of vegetable waste. The gasification of the briquettes was carried out in an open core downdraft gasifier, which resulted in syngas with a calorific value of 4.71 MJ Nm−3 at the gasification temperature between 889°C and 1011°C. A spark ignition, internal combustion engine was run on syngas and could generate a maximum load up to 10 kWe. The cold gas efficiency and the hot gas efficiency of the gasifier were measured at 74.11% and 79.87%, respectively. Energy recovery from the organic vegetable waste was possible through a thermochemical conversion route such as briquetting and subsequent gasification and recovery of the fuel for small-scale power generation.


1989 ◽  
Vol 7 (2) ◽  
pp. 116-127 ◽  
Author(s):  
Justas K. Laichena

Most rural people in Kenya rely principally on human and animal muscle power in their work as subsistence farmers, herdsmen, fisherman, or small-scale crop farmers. All the agricultural processes (ranging from ploughing to harvesting) are done largely by hand, with some help from draft animals and simple tools. Firewood is their principal cooking and heating fuel while kerosene in used for lighting. Their economic growth is hence blocked by the energy crisis. Due to their heavy dependence on biomass – mainly firewood, crop residues, and animal dung – they deprive the soil of essential nutrients and pose a threat to the agricultural lands due to deforestation and the resulting soil erosion. The problem of rural energy, therefore places the provision of food and other basic needs at risk. A technology which extracts a more useful and convenient form of fuel from biomass without destroying its fertilizer value than the traditional conversion method of direct combustion is highly desirable. Anaerobic digestion of agricultural residues generates biogas which can be used directly for lighting, cooking, electricity generation, or to power an IC engine for water pumping or milling. The remaining sludge forms a good fertilizer. This paper reviews the role of biomass in meeting Kenya's energy needs and how biogas can contribute in alleviating the rural energy crisis. Biogas production and utilization technology was introduced in Kenya in 1954 but by 1986 there were less than 200 installed biogas plants and less than 25% of these were operational. A survey of installed biogas plants (across the country) was carried out (using questionnaires and interviews) to identify the factors that have inhibited the adoption of biogas technology in Kenya; and the problems which have caused the failure of many of the installed plants. The paper gives a detailed discussion of the findings. The survey showed that amoung the reasons for nonadoption are: lack of capital and sufficient input materials (animal dung and water); limited dissemination of technical knowledge and experience to operate biogas plants; and the lack of credit and extension facilities. It was also found that problems such as scum build-up and corrosion, and the lack of sufficient knowledge on the operation and maintenance of the digesters especially on feeding and feedstock dilution (leading to low gas production) has resulted to many failures. The paper attempts to answer some of the problems which have resulted to the many failures and hindered widespread acceptance of biogas technology in Kenya. Finally the issue of dissemination is discussed.


2020 ◽  
Vol 19 (2) ◽  
pp. 138
Author(s):  
Najwa Hayati Abdul Halim ◽  
Suriyati Saleh ◽  
Noor Asma Fazli Abdul Samad

Biomass gasification is widely used for converting solid biomass into synthesis gas for energy applications. Raw biomass is commonly used as feedstock for the gasification process but it usually contains high moisture content and low energy value which lowering synthesis gas production. Thus, torrefaction as a pre-treatment process is necessary in order to upgrade the properties of feedstock for producing more synthesis gas production and improving gasification performance. The objective of this work is to study the effect of gasification temperature on the synthesis gas production and gasification performance using raw and torrefied palm mesocarp fibre (PMF). The gasification process is conducted using bubbling fluidized bed using steam as gasifying agent. Based on experimental work, by increasing gasification temperature from 650 – 900 °C, the compositions of hydrogen and carbon monoxide gases were enhanced greatly while carbon dioxide and methane gases were decreased for both raw and torrefied PMF. In terms of gasification performance, synthesis gas yield for raw and torrefied PMF is increased from 0.91 to 1.23 Nm3/kg and 1.10 to 1.35 Nm3/kg respectively. Besides, lower heating value (LHV) of torrefied PMF is 0.04 MJ/Nm3 higher than raw PMF at 900 °C. The result showed that the percentage of cold gas efficiency (CGE) reached maximum of 67% for raw PMF while carbon conversion (CC) at 85.6% for torrefied PMF at a gasification temperature of 900 °C. The higher CC obtained by torrefied PMF is because of the increment of carbon content from 45.2% to 53.7% as a result of torrefaction. Gasification temperature of 800 °C showed the best performance of the PMF gasification since the maximum performances of LHV is achieved and started to decrease once the gasification temperature is operated beyond 800 °C.


2019 ◽  
Vol 25 (4) ◽  
pp. 329-339
Author(s):  
João Cardoso ◽  
Valter Silva ◽  
Daniela Eusébio ◽  
Tiago Carvalho ◽  
Paulo Brito

A 2-D numerical simulation approach was implemented to describe the gasification process of olive pomace in a bubbling fluidized bed reactor. The numerical model was validated under experimental gasification runs performed in a 250 kWth quasi-industrial biomass gasifier. The producer gas composition, H2/CO ratio, CH4/H2 ratio, cold gas efficiency and tar content were evaluated. The most suitable applications for the potential use of olive pomace as an energy source in Portugal were assessed based on the results. A techno-economic study and a Monte Carlo sensitivity analysis were performed to assess the feasibility and foresee the main investment risks in conducting olive pomace gasification in small facilities. Results indicated that olive pomace gasification is more suitable for domestic purposes. The low cold gas efficiency of the process (around 20%) turns the process more appropriate for producer gas production in small cogeneration facilities. Olive pomace gasification solutions showed viable economic performance in small cogeneration solutions for agriculture waste-to-energy recovery in olive oil agriculture cooperatives. However, the slender profitability may turn the project unattractive for most investors from a financial standpoint.


2019 ◽  
Vol 38 (2) ◽  
pp. 406-416 ◽  
Author(s):  
Marcel Mikeska ◽  
Jan Najser ◽  
Václav Peer ◽  
Jaroslav Frantík ◽  
Jan Kielar

Gas from the gasification of pellets made from renewable sources of energy or from lower-quality fuels often contains a number of pollutants. This may cause technical difficulties during the gas use in internal combustion gas engines used for energy and heat cogeneration. Therefore, an adequate system of gas cleaning must be selected. In line with such requirements, this paper focuses on the characterization and comparison of gases produced from different types of biomass during gasification. The biomass tested was wood, straw, and hay pellets. The paper gives a detailed description and evaluation of the measurements from a fix-bed gasifier for the properties of the produced gases, raw fuels, tar composition, and its particle content before and after the cleaning process. The results of elemental composition, net calorific value, moisture, and ash content show that the cleaned gases are suitable for internal combustion engine-based cogeneration systems, but unsuitable for gas turbines, where a different cleaning technology would be needed.


2016 ◽  
Author(s):  
A. Ribeiro ◽  
C. Vilarinho ◽  
J. Araújo ◽  
J. Carvalho

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Wail Aladayleh ◽  
Ali Alahmer

This paper investigates the potential of utilizing the exhaust waste heat using an integrated mechanical device with internal combustion engine for the automobiles to increase the fuel economy, the useful power, and the environment safety. One of the ways of utilizing waste heat is to use a Stirling engine. A Stirling engine requires only an external heat source as wasted heat for its operation. Because the exhaust gas temperature may reach 200 to 700°C, Stirling engine will work effectively. The indication work, real shaft power and specific fuel consumption for Stirling engine, and the exhaust power losses for IC engine are calculated. The study shows the availability and possibility of recovery of the waste heat from internal combustion engine using Stirling engine.


2021 ◽  
Vol 13 (15) ◽  
pp. 8274
Author(s):  
Hasanain A. Abdul Wahhab ◽  
Hussain H. Al-Kayiem

The aggressive growth of Eichhornia crassipes (Water Hyacinth) plants causes severe damage to the irrigation, environment, and waterway systems in Iraq. This study aims to produce, characterize, and test biofuel extracted from the Eichhornia crassipes plant in Iraq. The extracted biodiesel was mixed at 10%, 20%, and 40% with neat diesel to produce three biodiesel samples. The methodology consists of the physiochemical properties of the samples that were characterized. The performance of the IC engine fueled by neat and biodiesel samples was measured under various operational conditions. The exhaust gases were analyzed to estimate the compounds to assess the environmental impact. The results showed that the density and viscosity of mixtures increase and the calorific value decrease with biodiesel. The engine test showed that the diesel + 10BE, diesel + 20BE, and diesel + 40BE enhanced brake thermal efficiency using 2.6%, 4.2%, and 6.3%, respectively, compared to neat diesel. Exhaust tests show a slight reduction, of 0.85–3.69% and 2.48–6.93%, in CO and HC emission, respectively. NOx is higher by 1.87–7.83% compared with neat diesel. The results revealed that biodiesel blended from Eichhornia crassipes is a viable solution to mitigate the drastic impact on the environment and economy in Iraq. The blended biodiesel has good potential to be mixed with the locally produced diesel from oil refineries.


2021 ◽  
pp. 146808742110464
Author(s):  
Yang Hua

Ether and ester fuels can work in the existing internal combustion (IC) engine with some important advantages. This work comprehensively reviews and summarizes the literatures on ether fuels represented by DME, DEE, DBE, DGM, and DMM, and ester fuels represented by DMC and biodiesel from three aspects of properties, production and engine application, so as to prove their feasibility and prospects as alternative fuels for compression ignition (CI) and spark ignition (SI) engines. These studies cover the effects of ether and ester fuels applied in the form of single fuel, mixed fuel, dual-fuel, and multi-fuel on engine performance, combustion and emission characteristics. The evaluation indexes mainly include torque, power, BTE, BSFC, ignition delay, heat release rate, pressure rise rate, combustion duration, exhaust gas temperature, CO, HC, NOx, PM, and smoke. The results show that ethers and esters have varying degrees of impact on engine performance, combustion and emissions. They can basically improve the thermal efficiency of the engine and reduce particulate emissions, but their effects on power, fuel consumption, combustion process, and CO, HC, and NOx emissions are uncertain, which is due to the coupling of operating conditions, fuel molecular structure, in-cylinder environment and application methods. By changing the injection strategy, adjusting the EGR rate, adopting a new combustion mode, adding improvers or synergizing multiple fuels, adverse effects can be avoided and the benefits of oxygenated fuel can be maximized. Finally, some challenges faced by alternative fuels and future research directions are analyzed.


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