scholarly journals THE INFLUENCE OF CHEMICAL IMPURITIES AND MECHANOCHEMICAL ACTIVATION ON THE RHEOLOGICAL PROPERTIES OF COAL-WATER SUSPENSIONS

2021 ◽  
Vol 1 ◽  
pp. 20-27
Author(s):  
A.V. Kravchenko
Keyword(s):  
Rheological Properties ◽  
Mechanochemical Activation ◽  
Experimental Studies ◽  
Electric Energy ◽  
Energy Resource ◽  
Fuel Mixture ◽  
Resource Base ◽  
Graphical Dependence ◽  
Coal Fuel ◽  
Fuel Mixtures

It is shown that the use of water-coal fuel mixtures as an energy resource in the production of heat and electric energy can not only significantly expand the resource base of the heat and power industry, but also improve the environmental performance of coal combustion on heat power equipment. One of the main problems of using coalwater fuel is its high viscosity, which complicates the processes of pumping and spraying during combustion. Optimization of the viscosity and other rheological properties of these fuel mixtures is achieved by adding chemical reagents-plasticizers. The experimental studies of the effect on the rheological properties of coal-water fuel mixtures of the use in the process of their production of plasticizers of various origins and modes of mechanochemical activation (grinding of the dispersed phase) have been carried out. For the research, plasticizing reagents were selected, which are used in various technologies for the preparation of water-coal fuel mixtures, and new reagents have been proposed. It was concluded that triethylamine has an advantage in use due to its effectiveness and relatively low cost. In this regard, a study of changes in the rheological properties of coal-water fuel with the addition of this reagent-plasticizer in the range from 0,5 to 3% of the total mass of the fuel mixture was carried out. The graphical dependence of the viscosity of coal-water fuel on the concentration of triethylamine has been obtained. An intensive decrease in fuel viscosity (from 0,95 to 0,8 Pa · s) was revealed in the range of additive concentrations of 0,5-1,0%. The study of the influence of the duration of hydrocavitation mechanochemical activation on the rheological properties of coal-water fuel has been carried out. A graphical dependence of the change in the viscosity of coal-water fuel on the duration of mechanochemical activation, which is characterized by a significant minimum of viscosity at the level of processing duration equal to 60 s, has beenobtained. Keywords: coal-water fuel, mechanochemical activation, plasticizing reagents, dynamic viscosity. Corresponding author V.A. Goman, e-mail: [email protected]

Development and Testing of a FuelFlex Dry-Low-NOx Micromix Combustor for Industrial Gas Turbine Applications With Variable Hydrogen Methane Mixtures

2019 ◽  
Author(s):  
H. H.-W. Funke ◽  
N. Beckmann ◽  
S. Abanteriba
Keyword(s):  
Gas Turbine ◽  
Experimental Studies ◽  
Fuel Mixture ◽  
Combustion Efficiency ◽  
Pollutant Emission ◽  
Pure Hydrogen ◽  
Negative Effects ◽  
Low Emission ◽  
Combustion Properties ◽  
Fuel Mixtures

Abstract The negative effects on the earth’s climate make the reduction of the potent greenhouse gases carbon-dioxide (CO2) and nitrogen oxides (NOx) an imperative of the combustion research. Hydrogen based gas turbine systems are in the focus of the energy producing industry, due to their potential to eliminate CO2 emissions completely as combustion product, if the fuel is produced from renewable and sustainable energy sources. Due to the difference in the physical properties of hydrogen-rich fuel mixtures compared to common gas turbine fuels, well established combustion systems cannot be directly applied for Dry Low NOx (DLN) hydrogen combustion. The paper presents initial test data of a recently designed low emission Micromix combustor adapted to flexible fuel operation with variable fuel mixtures of hydrogen and methane. Based on previous studies, targeting low emission combustion of pure hydrogen and dual fuel operation with hydrogen and syngas (H2/CO 90/10 vol.%), a FuelFlex Micromix combustor for variable hydrogen methane mixtures has been developed. For facilitating the experimental low pressure testing the combustion chamber test rig is adapted for flexible fuel operation. A computer-controlled gas mixing facility is designed and installed to continuously provide accurate and homogeneous hydrogen methane fuel mixtures to the combustor. An evaluation of all major error sources has been conducted. In the presented experimental studies, the integration-optimized FuelFlex Micromix combustor geometry is tested at atmospheric pressure with hydrogen methane fuel mixtures ranging from 57 vol.% to 100 vol.% hydrogen in the fuel. For evaluating the combustion characteristics, the results of experimental exhaust gas analyses are applied. Despite the design compromise, that takes into account the significantly different fuel and combustion properties of the applied fuels, the initial results confirm promising operating behaviour, combustion efficiency and pollutant emission levels for flexible fuel operation. The investigated combustor module exceeds 99.4% combustion efficiency for hydrogen contents of 80–100% in the fuel mixture and shows NOx emissions less than 4 ppm corrected to 15 vol.% O2 at the design point.

scholarly journals Criteria for Assessing the Energy-Ecological Effectiveness of using the Sludge of Waste Treatment Plants as Components of Liquid Composite Fuels

2020 ◽  
Vol 9 (4) ◽  
pp. 328
Author(s):  
Iryna Suvorova ◽  
Oleh Kravchenko ◽  
Vitalii Goman ◽  
Ihor Baranov
Keyword(s):  
Municipal Wastewater ◽  
Waste Treatment ◽  
Wastewater Treatment Plants ◽  
Energy Resource ◽  
Fuel Mixture ◽  
Fuel Oil ◽  
Industrial Wastes ◽  
Resource Saving ◽  
The Sustainable Development ◽  
Fuel Mixtures

The challenging issues in the sustainable development of a state currently are the problems of protecting the environment from contamination, increasing the capacity of systems for recycling and reusing water, and the development of resource saving and non-waste technologies. The authors have developed and introduced the technology of hydrocavitation activation of liquid hydrocarbons to create composite fuels that can contain off-spec hydrocarbons, including stale fuel oil, oil tanker outwashes, stillage bottoms, coal, bio mass, industrial wastes and the sludge of wastewater treatment plants. The main criteria were defined for assessing the energy-ecological effectiveness of using sludge in municipal wastewater as a component of composite fuels. The criteria are as follows: the calorific capacity of the fuel mixture, the energy effectiveness of its use as an energy resource, consumer properties, and the environmental performance of combusting this kind of fuel. Using these criteria during the production and combustion of composite fuels obtained with hydrocavitation activation allows producing high-quality fuel mixtures with specified thermophysical and consumer properties. This opens the prospects of more effective usage of hydrocarbon resources and of solving simultaneously two problems: the production of surplus energy and environmental load reduction during the disposal and neutralisation of moisture-containing waste. Keywords: sludge; hydrocarbon resources; hydrocavitation activation; composite fuels; waste disposal and neutralisation

Studying dispersed and rheological properties of hydrocarbon-containing acid emulsions and their efficiency in removing asphalt-resin-paraffin deposits

2020 ◽  
pp. 128-139
Author(s):  
M. Yu. Shumakher ◽  
V. V. Konovalov ◽  
A. P. Melnikov
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Rheological Properties ◽  
Reaction Rate ◽  
Experimental Studies ◽  
Efficient Removal ◽  
Reservoir Properties ◽  
Hydrocarbon Solvents ◽  
Formation Zone ◽  
Effect Of The Composition

Currently, the treatment of the bottomhole formation zone with acidic compositions is one of the most common methods to intensify the oil inflow. The use of various modified acid compositions increases the efficiency of acid treatments on the bottomhole formation zone. Acid compositions, including those containing hydrocarbon solvents, which contribute to more efficient removal of organic colmatants, affect the reaction rate of the reagent with the rock and processing equipment, change the reservoir properties, etc.The article presents the results of experimental studies, which are aimed at establishing the effect of the composition of hydrocarbon-containing acidic emulsions consisting of an aqueous solution of hydrochloric acid, toluene and Neonol AF 9-10 on their dispersed and rheological properties, as well as their efficiency in removing paraffin deposits.

scholarly journals Bioh2, Heat and Power from Palm Empty Fruit Bunch via Pyrolysis-Autothermal Reforming: Plant Simulation, Experiments, and CO2 Mitigation

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4767
Author(s):  
Lifita N. Tande ◽  
Erik Resendiz-Mora ◽  
Valerie Dupont
Keyword(s):  
Agricultural Waste ◽  
Experimental Studies ◽  
Energy Resource ◽  
Autothermal Reforming ◽  
Packed Bed Reactor ◽  
Sub Saharan Africa ◽  
Production Plant ◽  
Pure Hydrogen ◽  
Empty Fruit Bunch ◽  
Bio Oil

Empty fruit bunch, a significant by-product of the palm oil industry, represents a tremendous and hitherto neglected renewable energy resource for many countries in South East Asia and Sub-Saharan Africa. The design and simulation of a plant producing pure hydrogen through autothermal reforming (ATR) of palm empty fruit bunch (PEFB) was carried out based on successful laboratory experiments of the core process. The bio-oil feed to the ATR stage was represented in the experiments and in the simulation by a surrogate bio-oil mixture of 11 organic compounds shown to be main constituents of PEFB oil from previous work, and whose combined elemental composition and volatility was determined to be as close as possible to that of the real PEFB bio-oil. The experiments confirmed that H2 yields close to equilibrium predictions were achievable using an in-house synthetised Rh-Al2O3 catalyst in a packed bed reactor. Initial sensitivity analysis on the plant revealed that feed molar steam to carbon ratio should not exceed 3 for the optimal design of the ATR hydrogen production plant. An overall plant efficiency of 39.4% was obtained for the initial design, this value was improved to 67.5% by applying pinch analysis to enhance the integration of heat in the design. The proposed design renders CO2 savings of about 0.56 kg per kg of raw PEFB processed. The proposed design and accompanying experimental studies together make a strong case on the possibility of polygeneration of H2, heat, and power from an otherwise discarded agricultural waste.

Ultra-Low Emission Hydrogen/Syngas Combustion With a 1.3 MW Injector Using a Micro-Mixing Lean-Premix System

2011 ◽  
Author(s):  
Brian Hollon ◽  
Erlendur Steinthorsson ◽  
Adel Mansour ◽  
Vincent McDonell ◽  
Howard Lee
Keyword(s):  
Carbon Dioxide ◽  
Natural Gas ◽  
Flame Temperature ◽  
Fuel Mixture ◽  
Full Scale ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Fuel Injector ◽  
Nitrogen Dilution ◽  
Fuel Mixtures

This paper discusses the development and testing of a full-scale micro-mixing lean-premix injector for hydrogen and syngas fuels that demonstrated ultra-low emissions and stable operation without flashback for high-hydrogen fuels at representative full-scale operating conditions. The injector was fabricated using Macrolamination technology, which is a process by which injectors are manufactured from bonded layers. The injector utilizes sixteen micro-mixing cups for effective and rapid mixing of fuel and air in a compact package. The full scale injector is rated at 1.3 MWth when operating on natural gas at 12.4 bar (180 psi) combustor pressure. The injector operated without flash back on fuel mixtures ranging from 100% natural gas to 100% hydrogen and emissions were shown to be insensitive to operating pressure. Ultra-low NOx emissions of 3 ppm were achieved at a flame temperature of 1750 K (2690 °F) using a fuel mixture containing 50% hydrogen and 50% natural gas by volume with 40% nitrogen dilution added to the fuel stream. NOx emissions of 1.5 ppm were demonstrated at a flame temperature over 1680 K (2564 °F) using the same fuel mixture with only 10% nitrogen dilution, and NOx emissions of 3.5 ppm were demonstrated at a flame temperature of 1730 K (2650 °F) with only 10% carbon dioxide dilution. Finally, using 100% hydrogen with 30% carbon dioxide dilution, 3.6 ppm NOx emissions were demonstrated at a flame temperature over 1600 K (2420 °F). Superior operability was achieved with the injector operating at temperatures below 1470 K (2186 °F) on a fuel mixture containing 87% hydrogen and 13% natural gas. The tests validated the micro-mixing fuel injector technology and the injectors show great promise for use in future gas turbine engines operating on hydrogen, syngas or other fuel mixtures of various compositions.

Characterization of Spray Formed by Diesel-Water Mixture Jet Injected Into an Air Crossflow

2017 ◽  
Author(s):  
Jinkwan Song ◽  
Jong Guen Lee
Keyword(s):  
Diesel Fuel ◽  
Drop Size ◽  
Pure Water ◽  
Fuel Mixture ◽  
Water Mixture ◽  
Fuel Injector ◽  
Spray Characteristics ◽  
Two Fluids ◽  
Mixing Ratios ◽  
Fuel Mixtures

Using a mixture of water and diesel fuel is considered a way to reduce gas emissions including NOx and COx in the gas turbine. This paper presents experimental results on spray characteristics of the water-diesel fuel mixture in an air crossflow. A plain-orifice type injector of 0.508 mm in diameter is employed in the research. Pure water, pure diesel fuel, and water-diesel fuel mixtures with different mixing ratios are used to compare their spray characteristics. In order to observe spray behaviors in different breakup regimes, Weber numbers for water of 30 and 125 are chosen as the operating condition and the corresponding Weber numbers for diesel fuel at the same conditions are 92 and 382, respectively. Momentum flux ratios are 10 and 20. A tee connection and a subsequent static mixer are employed at upstream of fuel injector to mix two liquids. Phase Doppler Particle Analyzer (PDPA) measurement is performed to measure droplet distributions and mean drop size at various mixture ratios, and planar laser induced fluorescence (PLIF) technique with dyeing either diesel or water is used to look into the primary breakup process. PDPA data show that the spray characteristics of water-diesel fuel mixtures such as mean drop size and number density distribution can be predicted from the measured drop size distribution of pure fluids by weighting those quantities by mass fraction of each fluid, indicating that the water and diesel are injected alternately without significant mixing between the two fluids. A short transition of liquid flow from water-to-diesel or diesel-to-water produces small fraction of relatively bigger droplets.

scholarly journals Theoretical and experimental studies of a gas stamping device with a piston pressure multiplier

2019 ◽  
Vol 18 (1) ◽  
pp. 163-173
Author(s):  
A. Yu. Botashev ◽  
R. A. Bayramukov
Keyword(s):  
Theoretical Analysis ◽  
Experimental Studies ◽  
Fuel Mixture ◽  
Small Scale ◽  
Scale Production ◽  
Pressure Treatment ◽  
Energy Of Combustion ◽  
Stamping Process ◽  
Pressure Multiplier ◽  
The Matrix

In many industries, the share of small-scale production plants is significant. In these conditions, compared with traditional methods of pressure treatment, pulse pressure treatment methods, one of the varieties of which is gas stamping, are more efficient. However, the known devices of gas stamping provide mainly stamping of thin-walled parts. To expand the technological capabilities of gas stamping, the authors developed a gas stamping device with a piston pressure multiplier, in which heating and deformation of the stamping workpiece is carried out using the energy of combustion of fuel mixtures in the combustion chamber, in the working cylinder and in the cavity of the matrix. This article is devoted to the study of the workflow of this device. Theoretical analysis of the workflow was carried out, and, as a result, a pattern was determined for the variation of the pressure that performs the stamping process in the working cylinder. In particular, it was found that at the final stage of the stamping process, due to the energy of combustion of the fuel mixture, the pressure in the working cylinder increases 1.5...2 times, which allows a significant increase in the thickness of the parts to be stamped. An experimental gas stamping device with a piston pressure multiplier was developed, and experimental studies were carried out. The studies confirmed the main results of the theoretical analysis: the discrepancy between the theoretical and experimental values of the degree of pressure multiplication in the working cylinder does not exceed 11%.

scholarly journals EVALUATION OF HYDROPHILIC GLOBULES WITH SODIUM ALGINATE CONTAINING A LACTIC ACID– CHITOSAN COMPLEX

2021 ◽  
Vol 26 ◽  
pp. 170-177
Author(s):  
Katarzyna Małolepsza-Jarmołowska ◽  
Keyword(s):  
Lactic Acid ◽  
Rheological Properties ◽  
Sodium Alginate ◽  
Contact Time ◽  
Experimental Studies ◽  
Vaginal Mucosa

An important issue in the treatment of vaginitis is the amount of time the drug remains on the vaginal mucosa. If the contact time is too short, the drug cannot work effectively to ensure the correct pH in the vaginal environment. This study evaluated formulations of globules containing sodium alginate, lactic acid and chitosan with different pH and rheological properties. The experimental studies revealed that it is possible to produce a preparation with optimal pharmaceutical and application properties. The use of an appropriate ratio of lactic acid to chitosan in the complex and the appropriate concentration of sodium alginate produces a preparation with excellent properties to coat the surface of the vaginal mucosa.

scholarly journals Use of the mathematical model of the ignition system to analyze the spark discharge, including the destruction of spark plug electrodes

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Sebastian Różowicz
Keyword(s):  
Mathematical Model ◽  
Experimental Studies ◽  
Fuel Mixture ◽  
Spark Discharge ◽  
Fuel Additives ◽  
Ignition System ◽  
Spark Plug ◽  
The Mathematical Model

Abstract The paper presents the results of analytical and experimental studies concerning the influence of different kinds of fuel additives on the quality of the spark discharge for different configurations of the ignition system. The wear of the spark plug electrode and the value of spark discharge were determined for various impurities and configurations of the air-fuel mixture.

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