Search results for "combustion"

Numerical study of electrodynamic control of straw co-firing with propane

2019

Catalytic combustion of ethane over high surface area Ln1−xKxMnO3 (Ln = La, Nd) perovskites: The effect of potassium substitution

1997

Publisher Summary As a general trend, the substitution of the rare earth cation by potassium decreased the intrinsic activity, reduced the reaction order in oxygen, and, for the more substituted samples (x>0.10), it increased the selectivity to ethene. Supported platinum or palladium catalysts have so far been used almost exclusively, because of their excellent activity. However, their high price, tendency to be poisoned, and volatility in some applications have estimulated the search for suitable substitutes. LaCoO3, as a potential auto exhaust catalyst, starting a wide interest in the catalytic properties of perovskites. Their specific application as catalysts in flameless combustion has …

BIOMASS UTILIZATION AS A RENEVABLE ENERGY SOURCE IN POLISH POWER INDUSTRY – CURRENT STATUS AND PERSPECTIVES

2015

The depletion of the conventional energy sources, as well as the degradation and pollution of the environment by the exploitation of fossil fuels caused the development of renewable energy sources (RES), including biomass. In Poland, biomass is the most popular renewable energy source, which is closely related to the obligations associated with the membership in the EU. Biomass is the oldest renewable energy source, and its potential, diversity and polymorphism place it over other sources. Besides, the improvement in its parameters, including an increase in its calorific value, resulted in increasing use of biomass as energy source. In the electric power industry biomass is applied in the p…

Physical properties of aerosol particles measured from a bubbling fluidized bed boiler

2015

Abstract Increased use of biomass and waste fuels, and the consequent corrosion problem have led to an increased need to study and monitor the combustion processes. This study presents an extensive physical characterization of aerosol particles measured from a bubbling fluidized bed boiler with different fuel mixtures and optional ferric sulfate feeding. The fuel mixtures included bark, sludge, peat and solid recovered fuel. Previously, the characterization of the particles analyzed from a fluidized bed reactor has mainly focused on chemical off-line analysis of collected impactor samples, large coarse mode particles or laboratory-scale reactors. In this study, the focus is in the particle …

Electric Field Impact On The Biomass Gasification And Combustion Dynamics

2015

Experimental investigations of the DC electric field effect on thermal decomposition of biomass, formation of the axial flow of volatiles (CO, H2, CxHy), mixing of volatiles with swirling airflow at low swirl intensity (S ≈ 0.2-0.35), their ignition and on formation of combustion dynamics are carried out with the aim to understand the mechanism of electric field influence on biomass gasification, combustion of volatiles and heat energy production. The DC electric field effect on combustion dynamics was studied by varying the positive bias voltage of the central electrode from 0.6 kV to 3 kV, whereas the ion current was limited to 2 mA. The results of experimental investigations confirm the …

Preliminary Experimental Study on Double Fuel HCCI Combustion

2015

AbstractThis paper regards an experimental study on a particular internal combustion engine process which combines Double Fuel combustion with Homogeneous Charge Compression Ignition (HCCI) using mixtures of natural gas (NG) and gasoline. The tests performed on a CFR engine demonstrate that HCCI combustion can be achieved using NG-gasoline mixtures without knocking occurrence for low to medium engine load varying the proportion between the two fuels. The main advantage of this new combustion process relies on the noticeable higher engine efficiency obtained with respect to conventional spark ignition operation, and on the strong reduction of NOX emissions.

The different catalytic behaviour in the propane total oxidation of cobalt and manganese oxides prepared by a wet combustion procedure

2013

Abstract Cobalt oxide and manganese oxide catalysts have been prepared through aqueous synthesis using a wet combustion procedure. These materials have been tested as catalysts for the total oxidation of propane. It has been observed a different catalytic behaviour between cobalt and manganese oxides although for both oxides a very high catalytic activity has been obtained. Cobalt oxides prepared by the wet combustion procedure are less reactive than a simple cobalt oxide prepared without the addition of organic acids. However, in the case of manganese oxide the use of organic acids highly increases the catalytic activity. The different catalytic behaviour has been related to the variation …

Promoting the activity and selectivity of high surface area Ni–Ce–O mixed oxides by gold deposition for VOC catalytic combustion

2011

Gold supported on nickel cerium oxide catalysts (Ni–Ce–O) have been studied for the total oxidation of propane, as a model for hydrocarbon volatile organic compound emission control. High surface area Ni–Ce–O catalysts were synthesized using a very simple evaporation method, where cerium and nickel salts were evaporated in the presence of a mixture of methanol and oxalic acid. Gold catalysts were prepared following a deposition–precipitation method. A very efficient catalyst for the oxidation of propane, in terms of both activity and selectivity, was obtained. This high activity has been related to the high surface area of the catalyst (and therefore to the presence of more active sites ava…

Organic matter and wettability characteristics of wildfire ash from Mediterranean conifer forests

2015

Abstract Thermogravimetric analysis (TGA) and water repellency (wettability) determination of ash samples collected following wildfires at four different Mediterranean conifer forest sites in eastern Spain were conducted to provide insights into variations in key chemical and physical characteristics of ash. TGA allowed the evaluation of organic matter (OM) and inorganic carbonate (IC) characteristics and their role in ash wettability. Thermogravimetric profiles were recorded for 40 ash samples (ten from each site). The persistence of water repellency of all ash samples was assessed by the Water Drop Penetration Time (WDPT) test. OM contents decreased, whilst OM stability indices and IC con…

THE POSSIBILITY OF DISPOSING OF SPENT COFFEE GROUND WITH ENERGY RECYCLING

2015

The current policy of waste management requires, above all, a gradual reduction of waste amount and, to a larger extent, forces us to seek new methods of waste disposal. Recycling the energy contained in biomass waste is a more and more universally applied method of thermal converting. Biomass combustion allows saving fossil fuels which fits into sustainable development. This paper checks the possibility of using spent coffee ground (SCG) in energy recycling using a combustion process. This particular biomass type up to now has not been widely examined, which inclines to consider its usage as a potential additive to alternative fuels. In the study, we examined the quality of fuel, which was…