scholarly journals Planning for Reliable Coal Quality Delivery Considering Geological Variability: A Case Study in Polish Lignite Mining

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Wojciech Naworyta ◽  
Szymon Sypniowski ◽  
Jörg Benndorf
Keyword(s):  
Quality Control ◽  
Power Plants ◽  
Calorific Value ◽  
Drill Hole ◽  
Raw Material ◽  
Sequential Gaussian Simulation ◽  
Integrated Analysis ◽  
Coal Quality ◽  
Advantages And Disadvantages ◽  
Design Options

The aim of coal quality control in coal mines is to supply power plants daily with extracted raw material within certain coal quality constraints. On the example of a selected part of a lignite deposit, the problem of quality control for the run-of-mine lignite stream is discussed. The main goal is to understand potential fluctuations and deviations from production targets dependent on design options before an investment is done. A single quality parameter of the deposit is selected for this analysis—the calorific value of raw lignite. The approach requires an integrated analysis of deposit inherent variability, the extraction sequence, and the blending option during material transportation. Based on drill-hole data models capturing of spatial variability of the attribute of consideration are generated. An analysis based on two modelling approaches, Kriging and sequential Gaussian simulation, reveals advantages and disadvantages lead to conclusions about their suitability for the control of raw material quality. In a second step, based on a production schedule, the variability of the calorific value in the lignite stream has been analysed. In a third step the effect of different design options, multiple excavators and a blending bed, was investigated.

scholarly journals DEVELOPMENT OF RADIATION-PROOF CONCRETE COMPOSITIONS

2020 ◽  
Vol 3 (5) ◽  
pp. 24-33
Author(s):  
M. Sopin ◽  
Sergey Klyuev ◽  
Marina Ageeva ◽  
R. Lesovik ◽  
G. Bogusevich
Keyword(s):  
Water Consumption ◽  
Nuclear Power ◽  
Power Plants ◽  
Mechanical Characteristics ◽  
Nuclear Reactor ◽  
Coefficient Of Thermal Expansion ◽  
Raw Materials ◽  
Raw Material ◽  
Advantages And Disadvantages ◽  
Physical And Mechanical Characteristics

The article considers the possibility of using composite binders and magnetite as components of concrete with radiation-proof properties. The use of the developed concrete is possible not only when it is necessary to build nuclear power plants, but also to create bunkers or anti-radiation shelters. A special feature of concretes used for the protection and design of nuclear reactor cranes is their properties, which they must have. These properties include: low thermal conductivity, increased density, high temperature resistance, reduced values of the coefficient of thermal expansion, shrinkage and creep. Technogenic raw materials for the production of very heavy concrete are studied, the main physical and mechanical characteristics, the requirements that need to be considered in the selection of raw mix composition for protective concrete are analyzed. The paper presents a comparison of physical and mechanical characteristics, the advantages and disadvantages of introducing a binder of various types: cement, cement with a superlasticizer and a binder of low water consumption. It was found that the use of a low-water-consumption binder increases the physical and mechanical characteristics while reducing the consumption of cement in the raw material mix compared to traditional heavy concrete with cement.

scholarly journals Improving efficiency of thermal power plants through mine coal quality planning and control

2018 ◽  
Vol 22 (1 Part B) ◽  
pp. 721-733
Author(s):  
Mirjana Bankovic ◽  
Dejan Stevanovic ◽  
Milica Pesic ◽  
Aleksandra Tomasevic ◽  
Ljiljana Kolonja
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Calorific Value ◽  
Valuable Insight ◽  
Mining System ◽  
Coal Quality ◽  
Planning And Control ◽  
Control Units ◽  
Continuous Mining ◽  
And Control

The main goal of coal quality control in lignite mines is to supply coal to power plants within certain quality constraints. Coal properties can affect the efficiency, reliability, and availability of both the boiler and the emission control units. This paper presents a new based integrated mine process simulation approach to investigate the variability of the calorific value in exploitation a complex lignite deposits. Results provide valuable insight into the performance of a continuous mining system in terms of controlling coal quality variability.

Development of a Rapid Coal Analyzer Using Laser-Induced Breakdown Spectroscopy (LIBS)

2018 ◽  
Vol 72 (8) ◽  
pp. 1225-1233 ◽  
Author(s):  
Shunchun Yao ◽  
Juehui Mo ◽  
Jingbo Zhao ◽  
Yuesheng Li ◽  
Xiang Zhang ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Power Plants ◽  
Calorific Value ◽  
Utilization Efficiency ◽  
Quality Analysis ◽  
Laser Induced Breakdown Spectroscopy ◽  
Accurate Analysis ◽  
Coal Quality ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

Determination of coal quality plays a major role in coal-fired power plants and coal producers for optimizing the utilization efficiency and controlling the quality. In this work, a rapid coal analyzer based on laser-induced breakdown spectroscopy (LIBS) was developed for rapid quality analysis of pulverized coal. The structure of the LIBS apparatus was introduced in detail. To avoid time-consuming and complicated sample preparation, a pulverized feeding machine was designed to form a continuously stable coal particle flow. The standard deviation (SD) of characteristic peaks was used to estimate the spectral valid data in this experiment. Coupled with cluster analysis, artificial neural networks and genetic algorithm are employed as a nonlinear regression method in order to indicate the relationship between coal quality and the corresponding plasma spectra. It is shown that the average absolute error of ash, volatile matter, fixed carbon, and gross calorific value for the validation set is 0.82%, 0.85%, 0.96%, and 0.48 MJ/kg. The average standard deviation of repeated samples is 1.64%, 0.92%, 1.08%, and 0.86 MJ/kg, showing a high sample-to-sample repeatability. This rapid coal analyzer is capable of performing reliable and accurate analysis of coal quality.

scholarly journals Biomass as a raw material for energy production

2016 ◽  
Vol 3 (6) ◽  
pp. 251-255
Author(s):  
Michael Tsatiris ◽  
Kyriaki Kitikidou
Keyword(s):  
Energy Source ◽  
Energy Production ◽  
Lignin Content ◽  
Forest Biomass ◽  
Calorific Value ◽  
Dry Weight ◽  
Heat Energy ◽  
Raw Material ◽  
Biomass Combustion ◽  
Advantages And Disadvantages

In this paper, the meaning of biomass is defined and it is explained why it is a potential source of energy. The utilization of biomass as an energy source is based on heat energy production during its combustion. The solar energy captured and stored by plants is released in the form of heat energy during the biomass combustion. The variables that affect the energy value (calorific value) of forest biomass involve the chemical composition, percentage of extractives, moisture content, ash content and density. Softwoods generally contain more energy than hardwoods on a dry weight basis, due to higher lignin content plus the presence of more resinous extractives. Lastly, the advantages and disadvantages of biomass as an energy source are analyzed: biomass is renewable and eco-friendly, but its efficiency is low.

PROSPECTS OF OBTAINING ALTERNATIVE FUEL FROM VARIOUS BIOMASS AND WASTE SPECIES IN AZERBAIJAN

2019 ◽  
pp. 25-41
Author(s):  
O. M. Salamov ◽  
F. F. Aliyev
Keyword(s):  
Power Plants ◽  
Energy Intensity ◽  
Oil And Gas ◽  
Renewable Energy Sources ◽  
Calorific Value ◽  
High Energy ◽  
Energy Sector ◽  
Energy Sources ◽  
Mineral Fertilizers ◽  
Gaseous Fuels

The paper discusses the possibility of obtaining liquid and gaseous fuels from different types of biomass (BM) and combustible solid waste (CSW) of various origins. The available world reserves of traditional types of fuel are analyzed and a number of environmental shortcomings that created during their use are indicated. The tables present the data on the conditional calorific value (CCV) of the main traditional and alternative types of solid, liquid and gaseous fuels which compared with CCV of various types of BM and CSW. Possible methods for utilization of BM and CSW are analyzed, as well as the methods for converting them into alternative types of fuel, especially into combustible gases.Reliable information is given on the available oil and gas reserves in Azerbaijan. As a result of the research, it was revealed that the currently available oil reserves of Azerbaijan can completely dry out after 33.5 years, and gas reserves–after 117 years, without taking into account the growth rates of the exported part of these fuels to European countries. In order to fix this situation, first of all it is necessary to use as much as possible alternative and renewable energy sources, especially wind power plants (WPP) and solar photovoltaic energy sources (SFES) in the energy sector of the republic. Azerbaijan has large reserves of solar and wind energy. In addition, all regions of the country have large reserves of BM, and in the big cities, especially in industrial ones, there are CSW from which through pyrolysis and gasification is possible to obtain a high-quality combustible gas mixture, comprising: H2 + CO + CH4, with the least amount of harmful waste. The remains of the reaction of thermochemical decomposition of BM and CSW to combustible gases can also be used as mineral fertilizers in agriculture. The available and projected resources of Azerbaijan for the BM and the CSW are given, as well as their assumed energy intensity in the energy sector of the republic.Given the high energy intensity of the pyrolysis and gasification of the BM and CSW, at the present time for carrying out these reactions, the high-temperature solar installations with limited power are used as energy sources, and further preference is given to the use of WPP and SFES on industrial scale.

Recent Patents on Valve Mechanism Device

2020 ◽  
Vol 13 (3) ◽  
pp. 230-241
Author(s):  
Ye Dai ◽  
Hui-Bing Zhang ◽  
Yun-Shan Qi
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Flow Direction ◽  
Research Progress ◽  
Valve Mechanism ◽  
Advantages And Disadvantages ◽  
Valve Structure ◽  
Valve Leakage ◽  
Safety And Reliability

Background: Valves are an important part of nuclear power plants and are the control equipment used in nuclear power plants. It can change the cross-section of the passage and the flow direction of the medium and has the functions of diversion, cutoff, overflow, and the like. Due to the earthquake, the valve leaks, which will cause a major nuclear accident, endangering people's lives and safety. Objective: The purpose of this study is to synthesize the existing valve devices, summarize and analyze the advantages and disadvantages of various devices from many literatures and patents, and solve some problems of existing valves. Methods: This article summarizes various patents of nuclear-grade valve devices and recent research progress. From the valve structure device, transmission device, a detection device, and finally to the valve test, the advantages and disadvantages of the valve are comprehensively analyzed. Results: By summarizing the characteristics of a large number of valve devices, and analyzing some problems existing in the valves, the outlook for the research and design of nuclear power valves was made, and the planning of the national nuclear power strategic goals and energy security were planned. Conclusion: Valve damage can cause serious safety accidents. The most common is valve leakage. Therefore, the safety and reliability of valves must be taken seriously. By improving the transmission of the valve, the problems of complicated valve structure and high cost are solved.

Advantages and Disadvantages of Nephelometric Measurement of Serum Lipids

1974 ◽  
Vol 20 (4) ◽  
pp. 502-504 ◽  
Author(s):  
Daniel M Baer
Keyword(s):  
Quality Control ◽  
Serum Lipids ◽  
Serum Triglyceride ◽  
Chemical Methods ◽  
Unstable Material ◽  
Advantages And Disadvantages ◽  
Control Procedures ◽  
Frequent Problem

Abstract Several technical difficulties diminish the usefulness of serum triglyceride estimation by the method of Stone and Thorp [Clin. Chim. Acta 14, 812 (1966)]. An artificial and somewhat unstable material is used in the standardization. Falsely elevated readings caused by scratched cuvettes are a frequent problem. Conventional quality-control procedures cannot be used because stable preparations are not available. Specimen stability is a greater problem than with conventional chemical methods. In spite of these difficulties, the method can be useful, if its limitations are recognized, in measurements made on nonfasting individuals.

Advances in absorbents and techniques used in wet and dry FGD: a critical review

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lokesh Kumar ◽  
Susanta Kumar Jana
Keyword(s):  
Power Plants ◽  
Low Cost ◽  
Fine Particulate Matter ◽  
Packed Column ◽  
Toxic Substance ◽  
Cost Effective ◽  
Solid Wastes ◽  
Raw Material ◽  
Process Industries ◽  
Slurry Bubble Columns

Abstract Sulfur dioxide is considered as an extremely harmful and toxic substance among the air pollutants emitted from the lignite- and other high-sulfur-coal based power plants, old tires processing units, smelters, and many other process industries. Various types of absorbents and desulfurization technologies have been developed and adopted by the industries to reduce the emission rate of SO2 gas. The present paper focuses on the ongoing advances in the development of varieties of regenerative and non-regenerative absorbents viz., Ca-based, Mg-based, Fe-based, Na-based, N2-based, and others along with various FGD technology, viz., wet, dry or semi-dry processes. Additionally, different types of contactors viz., packed column, jet column, spray tower, and slurry bubble columns along with their significant operational and design features have also been discussed. In the existing or newly installed limestone-based FGD plants, an increasing trend of the utilization of newly developed technologies such as limestone forced oxidation (LSFO) and magnesium-enhanced lime (MEL) are being used at an increasing rate. However, the development of low-cost sorbents, particularly suitable solid wastes, for the abatement of SO2 emission needs to be explored sincerely. Many such wastes cause air pollution by way of entrainment of fine particulate matter (PM), groundwater contamination by its leaching, or brings damage to crops due to its spreading onto the cultivation land. One such pollutant is marble waste and in this work, this has been suggested as a suitable substitute to limestone and cost-effective sorbent for the desulfurization of flue gases. The product of this process being sellable in the market or may be used as a raw material in several industries, it can also prove to be an important route of recycling and reuse of one of the air and water-polluting solid wastes.

Sign in / Sign up

Export Citation Format

Share Document