Intelligent Control and Maintenance Man-agement Integrated System Based on Multi-Agents for Coal-Preparation Plant

This paper discusses the progress of computer integrated processing （CIPS） of coal-preparation and then preserits an intelligence controlled production-process, device-maintenance and production-management system of coal- preparation based on multi-agents （IICMMS-CP）. The construction of the IICMMS-CP, the distributed network control system based on live intelligence control stations and the strategy of implementing distributed intelligence control system are studied in order to overcome the disadvantages brought about by the wide use of the PLC system by coaipreparation plants. The software frame, based on a Multi-Agent Intelligence Control and Maintenance Management integrated system, is studied and the implemention methods of IICMMS-CP are discussed. The characteristics of distributed architecture, cooperation and parallel computing meet the needs of integrated control of coal-preparation plants with large-scale spatial production distribution, densely-related processes and complex systems. Its application further improves the reliability and precision of process control, accuracy of fault identification and intelligence of production adjustment, establishes a technical basis for system integration and flexible production. The main function of the system has been tested in a coal-preparation plant to good effect in stabilizing product quality, improving efficiency and reducing consumption.

The beneficiation of tailing of coal preparation plant by heavymedium cyclone

Dense-medium cyclones have been used for beneficiation of fine particles of coal. In this study, the usability of cyclones in the beneficiation of tailings of a coal preparation plant was investigated. For this purpose, separation tests were conducted using spiral concentrator and heavy medium cyclones with the specific weight of medium 1.3-1.8 （g/cm^3） on different grading fractions of tailing in an industrial scale （the weight of tail sample was five tons）. Spiral concentrator was utilized to beneficiate particles smaller than 1 mm. In order to evaluate the efficiency of cyclones, sink and float experiments using a specific weight of 1.3, 1.5, 1.7 and 1.9 g/cm^3, were conducted on a pilot scale. Based on the obtained results, the recovery of floated materials in cyclones with the specific weight of 1.40, 1.47 and 1.55 g/cm^3 are 17.75%, 33.80%, and 50%, respectively. Also, the cut point （Pso）, which is the relative density at which particles report equally to the both products are 1.40, 1.67 and 1.86 g/cm^3. The probable errors of separation for defined specific weights for cyclones are 0.080, 0.085 and 0.030, respectively. Also, the coefficients of variation was calculated to be 0.20, 0.12 and 0.03. Finally, it could be said that the performance of a cyclone with a heavy medium of 1.40 g/cm^3 specific weight is desirable compared with other specific weights.

Cause Analysis and Countermeasure of Gypsum Rain in Coal-fired Power Plants

Focusing on the phenomenon of gypsum rain while wet desulphurization(WFGD) were adopted in coal fired power plant without GGH, the paper studied and put forward the solutions : (1) desulfurization facilities related equipment modification;(2) optimal operation of existing desulfurization facilities.

Damage and deterioration mechanism and curing technique of concrete structure in main coal cleaning plants

Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian mine of the Xuzhou Mining Group Co. Ltd. In these projects, the operating environment and reliability of concrete structures in the main plants of the three companies were investigated and the safety of the structures inspected. Qualitative and quantitative analyses were made on the special natural, technological and mechanical environments around the structures. On the basis of these analyses, we discuss the long-term, combined actions of the harsh natural (corrosive gases, liquids and solids) and mechanical environments on concrete structures and further investigated the damage and deteriorating mechanisms and curing techniques of concrete structures in the main coal cleaning plants. Our study can provide a theoretical basis for ensuring the reliability of concrete structures in main coal cleaning plants.

Formation and emission characteristics of VOCs from a coal-fired power plant

On-site measurements of volatile organic compounds(VOCs)in different streams of flue gas were carried out on a real coal-fired power plant using sampling bags and SUMMA canisters to collect gas samples,filters to collect particle samples.Gas chromatography-flame ionization detector/mass spectrometry and gas chromatography-mass spectrometry was the offline analysis method.We found that the total mass concentration of the tested 102 VOC species at the outlet of wet flue gas desulfuration device was(13456±47)μg·m^(-3),which contained aliphatic hydrocarbons(57.9%),aromatic hydrocarbons(26.8%),halogen-containing species(14.5%),and a small amount of oxygen-containing and nitrogencontaining species.The most abundant species were 1-hexene,n-hexane and 2-methylpentane.The top ten species in terms of mass fraction(with a total mass fraction of 75.3%)were mainly hydrocarbons with a carbon number of 6 or higher and halogenated hydrocarbons with a lower carbon number.The mass concentration of VOC species in the particle phase was significantly lower than that in the gas phase.The change of VOC mass concentrations along the air pollution control devices indicates that conventional pollutant control equipment had a limited effect on VOC reduction.Ozone formation potential calculations showed that aromatic hydrocarbons contributed the highest ozone formation(46.4%)due to their relatively high mass concentrations and MIR(maximum increment reactivity)values.

Development of a Raoult’s Law-Based Screening-Level Risk Assessment Methodology for Coal Tar and Its Application to Ten Tars Obtained from Former Manufactured Gas Plants in the Eastern United States

A Raoult’s law-based screening-level assessment methodology was developed to calculate the carcinogenic and non-carcinogenic risks from ingestion of coal tar-contaminated water and it was applied to ten coal tars obtained from sites in the eastern United States. This approach provides a simple risk screening based on the conservative assumptions of Tier 1 in both the ASTM RBCA methodology and the USEPA Soil Screening Guidance. Results across the ten tars exhibited similar patterns, even though the coal tars had significantly different chemical compositions, and in all cases the screening-level risks were above the USEPA thresholds. There was no appreciable difference in the total risks when using either the current USEPA 1993 PAH risk assessment guidance or the proposed 2010 guidance. Benzene, while present at low concentrations within the coal tars, posed the dominant risk and strong correlations were observed with the benzene mole fraction.

Land reclamation in the refuse dump of open coal mines and its following ecology principle

Through the research on the model of the land reclamation in the refuse dumpof Heidaigou open coal mines,it was concerned that ecology was the theoretical basic forthe land reclamation of open coal mines.According to the principle of ecological substitut-ing,the land reclamation can be divided into three stages:water and soil conservation,ecological performance and economic performance.Taking the land reclamation in the re-fuse dump of Heidaigou open coal mines as the practical example,explained the applica-tion of the ecological substituting principle on the land reclamation in the open coal mines.

Progress and prospects of innovative coal-fired power plants within the energy internet

The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society.

Environmental performance assessments of different methods of coal preparation for use in small-capacity boilers: experiment and theory

The purpose of this article is to receive environmental assessments of combustion of different types of coal fuel depending on the preparation(unscreened,size-graded,briquetted and heat-treated)in automated boilers and boilers with manual load-ing.The assessments were made on the basis of data obtained from experimental methods of coal preparation and calculated methods of determining the amount of pollutant and greenhouse gas emissions,as well as the mass of ash and slag waste.The main pollutants from coal combustion are calculated:particulate matter,benz(a)pyrene,nitrogen oxides,sulfur dioxide,carbon monoxide.Of the greenhouse gases carbon dioxide is calculated.As a result of conducted research it is shown that the simplest preliminary preparation(size-graded)of coal significantly improves combustion efficiency and environmental performance:emissions are reduced by 13%for hard coal and up to 20%for brown coal.The introduction of automated boil-ers with heat-treated coal in small boiler facilities allows to reduce emissions and ash and slag waste by 2-3 times.The best environmental indicators correspond to heat-treated lignite,which is characterized by the absence of sulfur dioxide emissions.

Tolerance Comparison Among Selected Spirulina Strains Cultured Under High Carbon Dioxide and Coal Power Plant Flue Gas Supplements

In order to explore the changes in the growth and protein contents of Spirulina and obtain a proper strain for the fixation of carbon dioxide(CO2 from flue gas,the strains isolated from the Spirulina farms and the strain 208 were cultured under different aeration conditions including no CO2,10%CO2 and coal power plant flue gas supplements.The physiological indexes including filament length,biomass yield and chlorophyll a,soluble protein and phycocyanin contents were determined,respectively.When cultured without CO2 supplement,the strain 4-5 exhibited the highest biomass yield(1.880 g L^(−1)and a specific growth rate(0.367 d−1.However,the specific growth rate of all strains decreased significantly when they were cultured under 10%CO2 and unfiltered coal power plant flue gas supplements.Considerable differences were noted in the performance of the experimental microalgal strains under different contemporaneous conditions.The strain 7-8 achieved the highest biomass yield(1.603 g L^(−1)and relatively high phycocyanin content(7.1%)under 10%CO2 supplement.We noted that strain 4-5 had the highest specific growth rate(0.182 d−1 and biomass yield(0.43 g L^(−1)under coal power plant flue gas supplement.Strain 6-10 displayed the highest soluble protein content(66.02%),and strain 7-8 showed the highest phycocyanin content(9.28%)under coal power plant flue gas supplement.

Study on Model for Assessment of Quality Management Performance of Coal Preparation Plant in CIMS

In this paper the method to calculate intangible quality cost is put forward for the first time based on the production and management characteristics of coal preparation plant. A model for assessment of quality management performance of coal preparation plant is established on the ground of quality cost. By using of CIMS integration environment the strategy to carry out the model and the application example are also offered. It provides a new and feasible way to assess performance quality management of coal preparation plant.

Evaluating the Technical and Economic Feasibility of Adding a Power Recovery System to the Steam Condenser of a Lignite Coal-Fired Power Plant

Steam is the typical working fluid to drive turbo-generators in coal-fired power plants. It is an effective working fluid, but some of its energy is extracted in an unusable form when condensed. A Power Recovery Cycle (PRC) using a more volatile Secondary Working Fluid (SWF) added to the steam cycle could improve energy efficiency. PRCs have been applied to the flue gas and for combined cycle systems but not to traditional plant steam cycles. This paper details an analysis of adding a steam cycle PRC to a 500 MW lignite coal-fired power plant. A validated model of the plant was developed and PRCs using the three most attractive SWFs, benzene, methanol and hydrazine, were then added to the model. Adding a benzene, methanol, or hydrazine steam cycle PRC will produce an additional 59, 34, and 49 MW, respectively. An AACE Class 4 factored broad capital cost estimate and comparable operating costs and revenue estimates were developed to evaluate PRC feasibility. The benzene, methanol, and hydrazine processes had 2019 Net Present Values (NPVs) @12% of -$32, -$59, and +$35 million ± 40%, respectively. Thus, a PRC may be profitable at current or modest increases to U.S. Upper Midwest electricity prices of around $0.0667/kWh.

Feasibility Ananlysis of Building Pithead Power Plants in North Shaanxi and Ningxia Coal Bases

North Shaanxi and Ningxia are extremely abundant in coal resources, with excellent geographical positions and transport facilities, suitable to build large size pithead power plants. This paper details the coal resources in North Shaanxi Province and Ningxia Autonomous Region, fuel coal and transportation conditions for building large size pithead power plants, and carries out the analyses of economic benefits and electricity prices of bidding for access to grid for the six recommended power plants. The analyses show that these power plants, after built up, will have strong competitive powers and make contributions for the sustainable development of power industry in North China and Shandong Province.

COMPARATIVE RESEARCH ON THE CHARACTERISTICS OF THE FLYASH FROM COAL REFUSE-FIRED AND COAL-FIRED POWER PLANTS

The physical,chemical and mineral facies properties of the flyash from Xiezhuang Coal Refuse Fired Power Plant have been studied by means of naked eyes,microscope,chemical composition analysis and XRD analysis,and compared with that of the flyash from Taian Coal Fired Power Plant.The result shows that the flyash from coal refuse fired power plant is of better quality in making construction items,for being brighter in color,fine and high activity.Some ways of comprehensive utilization of the ash have been suggested in this paper.

Preparation of magnetically separable mesoporous activated carbons from brown coal with Fe3O4

Magnetically separable mesoporous activated carbon was prepared from brown coal in the presence of Fe3O4 as a bi-functional additive.Magnetic activated carbon(MAC)was characterized by lowtemperature nitrogen adsorption,scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and vibrating sample magnetometry(VSM).The evolution behaviors and transition mechanism of Fe3O4 during the preparation of MAC were investigated.The results show that prepared MAC with 6 wt%Fe3O4 addition having a specific surface area and mesopore ratio of 370 m^2·g^-1 and 55.7%,which meet the requirements of adsorption application and magnetic recovery.Highly dispersed iron-containing aggregates with the size of 0.1 lm in the MAC were observed.During the preparation of MAC,Fe3O4 could enhance the escape of volatiles during the carbonization.Fe3O4 could also accelerate burning off the carbon wall during activation,which leads to enlarging micropore size,then resulting in the generation of mesopore and macropore.As a result,a part of Fe3O4 converted into FeO,FeOOH,a-Fe,c-Fe,Fe2SiO4 and compound of Aluminum-iron-silicon.The prepared activated carbon,which was magnetized by both of residual Fe3O4,reduced a-Fe and c-Fe,can be easily separated from the original solution by external magnetic field.

A review of state-of-the-art processing operations in coal preparation

Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.

On 3D Geo-visualization of a Mine Surface Plant and Mine Roadway

Constructing the 3D virtual scene of a coal mine is the objective requirement for modernizing and processing information on coal mining production. It is also the key technology to establish a ＂digital mine＂. By exploring current worldwide research, software and hardware tools and application demands, combined with the case study site （the Dazhuang mine of Pingdingshan coal group）, an approach for 3D geo-visualization of a mine surface plant and mine roadway is deeply discussed. In this study, the rapid modeling method for a large range virtual scene based on Arc/Info and SiteBuilder3D is studied, and automatic generation of a 3D scene from a 2D scene is realized. Such an automatic method which can convert mine roadway systems from 2D to 3D is realized for the Dazhuang mine. Some relevant application questions are studied, including attribute query, coordinate query, distance measure, collision detection and the dynamic interaction between 2D and 3D virtual scenes in the virtual scene of a mine surface plant and mine roadway. A prototype system is designed and developed.

Spatiotemporal simulation and predication of heavy metal(loid) concentrations in coal chemical industrial areas with a soil environmental capacity model

Heavy metal (loid)(HM) accumulation in the soil and the HM spatiotemporal distribution have important implication for soil pollution prevention and remediation. The present study investigated the concentrations and spatiotemporal distributions of lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr) and arsenic (As) in the topsoil of a coal chemical plant in Ningxia Aulonomous region (Ningxia), China. Topsoil samples (/?= 153) were obtained using the checkerboard method, and the HM concentrations were determined. The soil residual rates of the five HMs were measured with leaching experinients and were applied in a soil environmental capacity model to predict the quarHitiHive variation of the HM concentrations. The predicted results were employed to estimate the HM spatiotemporal distribution within 2() years with the Kriging technique. The number of sampling sites, where all five HM concentratio ns exceed their corresponding background values in Ningxia, would be increased from 0 to 90% within 1() years of the plant operation. In addition, Pb and Cd were distributed along the traffic routes. Mercury and As were distributed near fuel gas emission vents. Chromium was mainly accumulated in slag dumps. The study may provide the theoretical and practical foun d at ion for future HM pollution control in coal chemical plants.