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Operational surveillance of all vital parts of thermal power plants is nowadays more important than any time before due to requirements for their extremely flexible operation resulting from intermittent behaviour of renewable energy sources. New methods for online measuring of pneumatic transport provide new possibilities for control and early fault detection of coal grinding and conveying system in direct-fired power plant boilers. Arrays of intrusive electrostatic sensors are an attractive option due to their inexpensive application and good spatial sensitivity required in large rectangular ducts of pulverized-coal systems. In this study, statistically treated electrostatic signals are used for detection of unexpected change in operating regime of coal grinding and conveying. Model-based and model-free autocorrelation reduction techniques are used to reduce the inherent autocorrelation of data. Forming batch-means of data, a model-free autocorrelation reduction technique is proposed in combination with an autoregressive-integrated-moving-average (ARIMA) method. Residuals between real and ARIMA-model fitted data are entered into exponentially-weighted-moving-average (EWMA) control chart for statistical surveillance of the process. The robust and cost-effective measuring method accompanied with a simple and intuitive control scheme proves to be effective for early fault detection of the pulverized-coal preparation system.

The goal of this research is to establish the applicability of an electrostatic measuring technique for monitoring the quality of a coal-milling process in direct-firing systems. Such systems are used in large steam boilers fired with low-rank coal where the pulverized coal is transported pneumatically from the mills to the burner nozzles via ducts with large cross-sections. The electrostatic measuring method, in connection with intrusive rod-type sensors, was studied because it provides good spatial sensitivity and cost effectiveness. A laboratory test rig was constructed, where the pulverized coal carried by ambient air was employed for the experiments emulating the pneumatic transport of coal particles in direct-firing systems. The test rig enables an extensive variation of the most influential parameters, like the mass flow, the velocity and the size of the particles. A linear, multiregression analysis of the results of the experiments was carried out and the appropriate regression model enabling a determination of the mean diameter of the particles using the electrostatic signal was chosen. Based on the results of the study the electrostatic measuring technique can be used for monitoring the size of pneumatically transported particles. The appropriate regression model needs to be chosen for each particular application to describe the dependency of the acquired electrostatic signal on the influential parameters of the pneumatic transport.

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The aim of SEEP2017 is to bring together the researches within the field of sustainable energy and environmental protection from all over the world.The contributed papers are grouped in 18 sessions in order to provide access to readers out of 300 contributions prepared by authors from 52 countries.We thank the distinguished plenary and keynote speakers and chairs who have kindly consented to participate at this conference. We are also grateful to all the authors for their papers and to all committee members.We believe that scientific results and professional debates shall not only be an incentive for development, but also for making new friendships and possible future scientific development projects. Increasing efforts and resources have been devoted to research during environmental studies, including the assessment of various harmful impacts from industrial, civic, business, transportation and other economy activities. Environmental impacts are usually quantified through Life Cycle Assessment (LCA). In recent years, footprints have emerged as efficient and useful indicators to use within LCA. The footprint assessment techniques has provided a set of tools enabling the evaluation of Greenhouse Gas (GHG) -including CO2, emissions and the corresponding effective flows on the world scale. From all such indicators, the energy footprint represents the area of forest that would be required to absorb the GHG emissions resulting from the energy consumption required for a certain activity, excluding the proportion absorbed by the oceans, and the area occupied by hydroelectric dams and reservoirs for hydropower.An overview of the virtual GHG flow trends in the international trade, associating the GHG and water footprints with the consumption of goods and services is performed. Several important indications have been obtained: (a) There are significant GHG gaps between producer's and consumer's emissions -US and EU have high absolute net imports GHG budget. (b) China is an exporting country and increasingly carries a load of GHG emission and virtual water export associated with consumption in the relevant importing countries. (c) International trade can reduce global environmental pressure by redirecting import to products produced with lower intensity of GHG emissions and lower water footprints, or producing them domestically.To develop self-sufficient regions based on more efficient processes by combining neighbouring countries can be a promising development. A future direction should be focused on two main areas: (1) To provide the self-sufficient regions based on more efficient processes by combining production of surrounding countries. (2) To develop the shared mechanism and market share of virtual carbon between trading partners regionally and internationally. HAKAN SERHAD SOYHAN 4 Development in energy sector, technological advancements, production and consumption amounts in the countries and environmental awareness give shape to industry of energy. When the dependency is taken into account in terms of natural...