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The selected fly ash, by product of coal combustion in thermal power plant, was tested to analyse its potential for use as supplementary cementitious material in cement-based composites, especially for the possibility of improving properties such as resistance and durability of the material. The chemical and physical properties of coal fly ash were characterised together with the determination of pozzolanic activity which was carried out by Frattini and Chapelle tests. The investigated material can be used as a pozzolanic active mineral admixture in the form of cement blends with the potential to improve the properties of cement-based composites. [ABSTRACT FROM AUTHOR]

A thermal process called torrefaction turns biomass into a substance that resembles coal and has superior fuel properties than the original biomass. Biomass that has been torrefied is more energy dense and hydrophobic, making it better for handling and storing. The objectives of this research are to develop a simulation model of the torrefaction process from Malaysian biomass and perform optimization for mass yield and energy consumption, and to integrate optimal torrefaction process into the existing biomass power plant. The process was simulated using ASPEN Plus. After EFB and other component is defined and properties method is selected depending on the process, the simulation model was developed by using model palette installed inside ASPEN to produce the desired torrefied EFB. For the base model of the simulation, crusher is used for size reduction, two separators and three RStoich model reactors are used for combustion and RYield model reactor for torrefaction. For optimization of mass yield and overall energy consumption, 6 option (simulation model 0 to 5) of design configurations were analysed. Retrofitting study on biomass-based power generation plant with torrefaction process is to improve the existing feedstock. Thus, 5 options (simulation option a to e) were constructed to further reduce the energy consumption of the total plant operation in the biomass power plant. The option was selected by lowest energy consumption, lowest integration cost and lowest annual utilities cost. Generally, the torrefaction technology is an improvement of biomass utilization technology and finally realize the maximum application of biomass energy. [ABSTRACT FROM AUTHOR]

Geopolymer mortar is made without using cement as a base material, but using other materials that contain silica and alumina. This element is widely found in industrial waste materials, such as fly ash. Fly ash is obtained from the residue of burning coal in a steam power plant. Geopolymer mortar has the disadvantage of low flexural strength, so it is brittle and breaks easily. This study aims to improve the flexural strength of fly ash-based geopolymer mortar with the addition of polypropylene fibers. The percentages of fiber added were 0.4%, 0.8%, 1.2%, and 1.6% by weight of fly ash. Fiber mixing to the dry mortar mixture. Tests conducted in the form of setting time, workability, compressive strength, flexural strength and visual observation of fiber attachment. The size of the specimens used is a 50x50x50mm cube and a 30x30x130mm block. Mechanical properties testing was carried out at 1, 3, 7 and 28 days of mortar age. The test results showed that addition of polypropylene fibers at 0,4%, increased compressive strength by 117,82%, namely 17,97MPa and the flexural strength increased by 76,06%, to 7,87MPa at 0,8% fiber percentage. Visual observation showed that geopolymer mortar has a more ductile failure behavior. [ABSTRACT FROM AUTHOR]

In Malaysia, coal is the largest fossil fuel used to generate power electricity which is 54.05%. By burning coal, greenhouse gas (GHG) emissions will continuously increase and affect global warming. Therefore, one of the alternatives is by promoting the co-firing coal and biomass in the existing coal-fired power plant in Malaysia. The past decade has seen an increase in the use of Computational Fluid Dynamic (CFD) to analyse the thermal performance of the coal-fired power plant. A coal-fired power plant for this study is referring to a 150MW subcritical boiler with tangential burner with the design pressure and temperature are 188 bar and 540 °C. This plant burned coal from Adaro and Hatillo. CFD simulation for co-firing is using 5% of sawdust at first level burners. From this study, several CFD methods were applied including the Eulerian-Langrangian approach to solve the two-phase gas-solid equation, Reynolds Averaged Navier Stokes (RANS) equation combined with k-ɛ Model to solve the turbulence problem in the gas phase, Discrete Ordinates Method (DO) to solve the radiative transfer equation (RTE) and Weighted Sum of Gray Gases Model (WSGGM) was used to calculate the absorption coefficient of the gas mixture. Based on the contour analysis result, found out that by co-firing coal and biomass, the burnout is reduced from an average of 0.45 kg/s to 0.33 kg/s when compared to pure coal combustion. This is mainly due to high volatile matters (VM) in the biomass. The concentration per unit thermal is also reduced to 42% when co-firing with sawdust. The early devolatilization will increase the gas and local temperature at each burner zone. The CO concentration was higher at the burner zone due to devolatilization. [ABSTRACT FROM AUTHOR]

The geographical position of PLTU Rembang, the Rembang Coal Steam Power Plant, which is located on the northern coast of Java, makes the area get a very large supply of sea breezes. The sea breeze can be used as an alternative energy source at the PLTU Rembang. For the target of renewable energy and environmentally friendly generation, it is planned to model a portable wind turbine for lighting lamps in the jetty area. In this study, a study of the wind potential in the jetty area was carried out. Wind data retrieval is done by using a wind speed detector. From the wind potential, a portable wind turbine design was carried out using CAD. The wind turbine selected is the savonius type with a variation of the number of blades 3. By considering the ease of making the rotor, the rotor diameter is designed with a size of 0.43 m and a height-to-diameter ratio of 1.2. The portable type was chosen for flexibility and considering the safety factor. [ABSTRACT FROM AUTHOR]

Power plant in Indonesia is still dominated by thermal plant from diesel fuel, gas and coal which cannot be renewed. The renewable energy potential in Indonesia is highly able to develop such as photovoltaic, wind turbine and micro hydro plant. Hybrid power plant system is a method of combining two or more plants in order to obtain the synergy which give a positive impact in technical (reliability supply system) and economic advantage. The main purpose of this research is to construct a controlling system of hybrid plant renewable energy to maintain the load supply by utilizing microcontroller ATMega2560 as the central of the control. The finding of this research is hybrid system which has constructed is well function with battery voltage value equal to 10 Volt as relay parameter to switch one power plant to another. [ABSTRACT FROM AUTHOR]

Increasing demand for electricity, in developing countries leads them to develop new technologies to generate power. At the same global warming and emission of CO2 and wastage of energy which is due to nearly 5-8% of the total electricity generation is due to various auxiliary process carries out at thermal power plant, the processes are moving and conveying fluid ,moving the fuel gases from furnaces, cooling ,condensing process etc. All these process are carried out by Induced Draft Fan, Compressors, Cooling Tower Fan, etc. This research work explains the implementation of variable frequency drives for the Induced draft fan and Cooling Tower Fan in the Thermal power plant is analyzed and calculations of energy conservation was carried using variable frequency drive. [ABSTRACT FROM AUTHOR]

The article is devoted to the development and justification of a method of burning solid household waste in a boiler furnace of a thermal power plant. This method was considered on the example of a steam boiler TPP-210A, which is installed at the Novocherkassk State District Power Station of the Rostov region. To describe the developed method, a thermal diagram was compiled indicating the main units involved in the combustion of household solid waste. All calculations were based on official reliable data obtained from open sources, for example, the "Territorial Waste Management Scheme of the Rostov Region" was taken as a source of an array of data on the amount of waste received annually. Analysis and comparison of fuel incinerated at TPP and waste coming to landfills of this power plant location area has been carried out. As a result of the calculation, the main parameters of the waste were identified (quantity - the share introduced into the main mass of coal fuel, type, method of processing) and operating modes of the thermal power plant at which the waste is burned. [ABSTRACT FROM AUTHOR]

Integrated gasification Combined cycle plants (IGCC) have high efficiency and minimal emissions of harmful substances, which makes them a promising technology for the energy production from coal. However, the cost of energy produced from IGCC remains high, which requires the improvement of IGCC technology. Increasing the efficiency and reducing the material consumption of IGCC is possible due to the addition of steam to the air blast in gasifier. To study the effect of steam addition on the gasification process, a one-dimensional kinetic-thermodynamic model has been developed that takes into account the chemical reaction inside the pores, the distribution of coal particles by size, the change in reaction order of steam gasification of coal, and the recirculation of coke-ash residue (CAR) from the gasifier outlet. Calculations of steam-air gasification of Kuznetsk coal in an industrial two-stage gasifier MHI for two types of coal grinding (ball mill and disintegrator) and three gasifier operation modes: nominal, pyrolysis (maximum recirculation of CAR) and flow (minimum recirculation of CAR) are carried out. Dependence cold gas efficiency of the gasifier from the steam / coal ratio is non-monotonic, associated with a change in the order of the steam gasification reaction. The maximum increase of cold gas efficiency is 0.5–9% abs. depending on the gasifier operation mode. [ABSTRACT FROM AUTHOR]

Global greenhouse issues and environmental policy among countries have been widely discussed. European Union (EU) and Asian countries including Japan, Korea, and Malaysia have introduced stringent environmental policies in reducing greenhouse impact from thermal coal plants. Coal was used as the main fuel due to its cheaper cost as compared to the other fuels such as natural gas and distillate. In fact, to ensure sustainability of the national grid system, coal power plants are still required to be in operation. However, coal behavior tends to deviate with different coal specifications such as gross calorific value (GCV). Coal GCV describes the energy content inside the coal in producing heat value. Besides, the different heat value produces different output such as SO2 and NO2 from the combustion process. This research aims to evaluate the impact towards combustion output based on a selection of coal type that is tested in a 700-megawatt thermal coal plant boiler. The study found high coal GCV will increase the production of SO2 and NO2 for every 10 kJ/kg by about 0.001% of SO2 and 0.002% of NO2. Nevertheless, this higher rate of production can be mitigated by introducing Flue Gas Desulphurization (FGD) while the boiler is in operation. [ABSTRACT FROM AUTHOR]

In ensuring the sustainability of energy security in the grid system, thermal coal plants were sustaining the baseload for most countries. Thus, it is essentially important to ensure the optimum operation of thermal coal plants in support of the national grid. Besides, to ensure that the operation of these plants meet the operational limit, critical parameters were the highlighted and identified. In fact, the operation of these plants significantly adheres to the thermodynamic process with the principle of heat transfer. Therefore, the experimental study was carried out to validate and identify the effect of coal combustion in the boiler parameters at the thermal coal plants generating 700 megawatts capacity. In observing the coal combustion effect, several types of coal were selected for this study. Temperature in the boiler indicates the boiler parameters are the impact from coal combustion. From the study, different types of coal resulted in a different effect on the boiler parameters such as Furnace Rear Path Temperature (FRPT), Furnace Exit Gas Temperature (FEGT) and Flue Gas Outlet Temperature (FRPT). The result shows boiler temperature with different types of coal at the temperature effect range; FPRT between 750-820°C, FEGT between 950-1200°C, and FRPT between 165-190°C. The results indicate the boiler parameters range is at acceptance limit with firing different types of coal. [ABSTRACT FROM AUTHOR]

Monitoring at six locations for samples of Total Suspended Particulate (TSP) ambient air around Pacitan Coal Steam Power Plant has been carried out. The purpose of this research is to characterize TSP and identify radioactivity around Pacitan Coal Steam Power Plant. The characteristics of TSP are determined by weighing before and after the weight of the TSP filter on the air pumping process at a constant, continuous speed for 24 hours. The Total Suspended Particulate (TSP) level around Pacitan Coal Steam Power Plant has the smallest value of 41.0 µg/m3 and the highest with a value of 67.9 µg/m3 resulting in an average value of 49.2±9.9 µg/m3. This average is still below the WHO air quality guidelines of 250 µg/m3. The radioactivity content of natural radionuclide air particulates including Th-232, Ra-226, Ra-228 and K-40 at 6 air sampling locations was determined using gamma spectrometers with HPGe detectors. The average activity concentration of Th-232, Ra-226, Ra-228 and K-40 in the TSP air particulate matter sample was 10.5; 14,0; 17,6; and 82.7 µBq/m3. The concentration value of radioactivity is still below the recommended value by Head Regulations of Nuclear Energy Regulatory Agency No. 7 in 2017 about the raw value of radioactivity levels in the air (Ra-226 with a value of 1800 µBq/m3 and Th-232 with a value of 2300 µBq/m3). From the results of TSP level analysis and radioactivity characteristics, air quality in the environment around Pacitan Power Plant is still safe for the people. [ABSTRACT FROM AUTHOR]

Efforts to fulfill the needs of electricity in Indonesia are still dominated by the use of fossil fuels such as coal in Steam Power Plants. However, the process of burning coal causes various environmental problems, one of which is fly ash. Fly ash is classified as a dangerous and toxic material. Although it is regarded as hazardous material, fly ash contains silica (SiO2) and alumina (Al2O3) which can be used as raw material for synthesis of aluminosilicate-based materials such as geopolymers, zeolites and others. In this study, the chemical composition, SiO2/Al2O3 ratio, and fly ash type will be examined from three different sources of fly ash such as power plants owned by a private company located in the Kapuas area (FA1), Asam-Asam's (FA2), and PulangPisau's (FA3) power plant. The chemical composition was tested by ASTM D 3682-13. Based on data, FA1 has the highest SiO2 and Al2O3 composition with a percentage of 56.44% and 31.31%, respectively. FA2 has the highest Fe2O3 composition with a percentage of 23.10% and FA3 has the highest CaO composition with a percentage of 23.46%. The highest SiO2/Al2O3 ratio is 4.61 from FA2, while the lowest SiO2/Al2O3 ratio is 1.80 from FA1. Based on the chemical composition of fly ash, FA1 and FA2 are classified as F type, while FA3 is classified as C type. From these data, it can be concluded that the fly ash from the three power plants still have the potential to be used as source for synthesis of aluminosilicate-based materials. [ABSTRACT FROM AUTHOR]

Sustainability in Supply Chain Management (SSCM) is extremely popular among researchers and practitioners since decades due to its multi-approach in nature. Thermal power plants have very bad images among other power generating industries due to its main staple coal, which is that the main source of generating power. Thanks to coal the Environmental performance is diminishing simultaneously decreasing Economic and Social performance, as SSCM is that the integration of Environmental, Social and Economic performance. Since Coal based power plants are in trouble and in target of pollution control panel and facing ecological issues, by adopting SSCM most vital issues like waste management, customer satisfaction and productivity are often achieved. So, during this paper ANN is implemented to seek out the foremost negative parameters of Thermal power plant Sustainable parameter which is creating barrier for customer satisfaction. [ABSTRACT FROM AUTHOR]

A significant share of problems in coal powered thermal plants is contributed by the wear of slurry pumps and the same has been tackled in the current study with the help of Cetyltrimethyl Ammonium Bromide (CTAB) as additive to the slurry. In present work, an erosion testing is done utilizing a Pot Tester setup for SS316 samples which is a common pump material. A comparative study on erosion behaviour of the as-received material is carried out by using a high concentration slurry (Cw = 60% by weight) with and without additives. The experiments are performed with four different rotational speeds of the samples (300, 400, 500 and 600rpm) while keeping the erodent impact angle as 90°. It is observed that the erosion rate increases with rotational speed for the both the cases (with and without additives). It is found that erosion rate decreases significantly by the use of additives in the slurry. A linear variation of weight loss with time is observed and an increase in wear with increasing rpm is also seen. [ABSTRACT FROM AUTHOR]

Air pollution is one of the greatest environmental evils. The Multi-Plume industrial source complex Short-term Period Regulatory (MPC-SPR) model is an alternate model to EPA and it is exclusively developed for regulatory purposes in India. The MPC-SPR model is based on a Gaussian Plume dispersion model from continuous elevated point sources. The processes as considered in the models are similar to ISCST3. The data requirements for dispersion analysis consist of three important parts: the emission inventory, the meteorological data and the monitoring data. A detailed emission inventory has been prepared by gathering data such as stack height, stack diameter, stack temperature, velocity, and rate of discharge of SO2 from the industries. Emission inventory has been Neyveli prepared data gathered from CARD such as stack coordinate, stack height, exit stack diameter and emission rate of SO2. The Meteorological data such as wind speed and Wind direction were observed from the Meteorological observatory at Vadalur. The hourly meteorological file to the MPC-SPR models have been prepared, which is similar to that of the ISCST3 model. The MPC-SPR Model was used to simulate the dispersion pattern of SO2 in the month of January 2019 by considering the emission from all the industrial stacks situated within the study area. [ABSTRACT FROM AUTHOR]

Indonesia is the country with the largest source of coal in the world, one of the region in Tarahan, Sumatera. Many power plants in Indonesia use coal as its main source, one of them in Suralaya. Coal is used as the main source of power generation because it has a heat value and considerable power compared to other generating sources. In addition, the price is relatively cheap to be one consideration of usage. Coal distribution process from Tarahan to Suralaya using barge. The use of barges is still widely used because it can bring considerable capacity and cheap shipping prices compared with other transportation During the shipping process, there is often a fire on coal in barges that greatly affects the safety and quality of coal itself. There have been cases of coal barge fires due to the heat energy incurred by the coal itself. Spontaneous combustion often occur as a result of a pile of coal in barges that are directly exposed by the environment causing spontaneous fires in coal. Environmental factors such as air, temperature, weather, and humidity are very influential. This method to prevent the spontaneous combustion of coal in barges is using the U-tube heat exchanger that is installed on the barge sideboards. The purpose of this research is to have preliminary design and calculate pump capacity of the heat exchanger system in the barge with the consideration of the loading and unloading process of coal so as not to interfere with the work process. Ratio of thermal transfer influence occurring in coal to heat exchanger placement distance to determinate the placement of the heat exchanger. The heat exchanger dimension value uses the pipeline surface area ratio to the coal surface area directly exposed by the environment. The preliminary design drawings of the heat exchanger in the barge are provided. The test results showed the necessary heat exchanger pipe design and placement on the barge to prevent spontaneous combustion. [ABSTRACT FROM AUTHOR]

The pyrolysis characteristics and kinetic parameters of coal and water hyacinth blend have been investigated by using thermogravimetric analysis. Those of pure coal and pure water hyacinth were also each studied as a comparison. The coal sample was taken from a Sub-district of Gunung Panjang, Berau, East Kalimantan, Indonesia. The as-received sample was ground to be a mesh size of 60. The sample of water hyacinth originated from Dams of Selorejo and Sengguruh, district of Malang, Indonesia. The raw material was cleaned with water and subsequently cut and dried at the temperature of around 85 °C for 6 hours. The dried biomass was then crushed and sieved at a size of 60 mesh as well. The blended fuel was composed of coal and water hyacinth in a mass ratio of 40:60 (wt%). The thermogravimetric experiment was performed for the coal, the water hyacinth, and their blend under the instrumentality of thermal analyzer at a single heating rate of 40 °C/min. The sample was heated up from 27 to 1000 °C with a nitrogen flow rate of 100 ml/min. Thermogravimetric (TG) and derivative thermogravimetric (DTG) curves were obtained. The kinetic evaluation was performed under the fitting method of Coats-Redfern. The results indicated that three stages of decomposition process were encountered during thermal degradation of the individual samples of coal and water hyacinth, as well as their blend. The addition of 60% water hyacinth to the coal provoked the thermal degradation toward the lesser temperature and forced the increase of maximum mass loss rate. The activation energy went to decrease together with the increasing of water hyacinth fraction, i.e., 84.02, 66.72, and 44.45 kJ/mol for respectively the coal, blended fuel, and water hyacinth. These results could be valuable in designing and developing of the reactor of the thermal conversion system on an industrial scale. [ABSTRACT FROM AUTHOR]

The prediction of gas-phase ignition characteristics of a coal dust layer by a hot metal particle located on its surface was performed by numerical simulation. The theoretical study results can be used in practice to develop the provisions of fire safety management aimed at preventing large fires and man-made disasters. In this paper we consider coal dust, the particle dispersion of which varies in the range of 0.1–1 mm. As local sources of heating steel disk-shaped and parallelepiped-shaped particles with the same specific size of 10 mm are used. The nonideality factor influence of the thermal contact of a local heat source and a dispersed brown coal layer on its gas-phase ignition delay-times when the parameters in the considered system vary over a wide range, including the initial temperatures of metal particles from 1100 to 1600 K. [ABSTRACT FROM AUTHOR]

The article presents the results of studies of the structure and properties of the waste of carbon enrichment - cake, electroplasma treated to develop a technique for obtaining organo-mineral porous material to implement the possibility of its practical application as a sorbent for wastewater treatment. We conducted a study termoactivation zone in the chamber electroplating reactor. The method of obtaining organomineral porous materials from coal cakes with the study of the elemental composition of raw materials before and after thermal activation is presented. Their most important physical and chemical properties are also studied. The result of the conducted researches the ability of thermoactivation of the coal cake, changing its material composition, the occurrence of porosity and the related sorption capacity applied for wastewater treatment. Thus, the waste of flotation of the coal cake is fundamentally suitable for the production from it of porous substances by the method of thermal degradation in electroplating reactor. [ABSTRACT FROM AUTHOR]

Thermal conversion of bituminous coal containing 5% by weight of copper nitrate (Cu(NO3)2) initiation additive which was applied by incipient wetness impregnation and mechanical activation has been studied. The experiment was conducted by thermogravimetric analysis at a heating rate of 2.5°C/min up to a maximum temperature of 600°C. Inert gas nitrogen with a flow rate of 60 ml/min was used as a medium. The beginning of the volatile compounds sublimation in modified samples occurs earlier in comparison with the reference samples regardless of the method of Cu(NO3)2 additive application to the coal sample. The essential difference in the thermal decomposition of the researched samples modified by various methods is stages of the process. Decomposition of copper nitrate is accompanied with the beginning of volatile compounds sublimation (in the case of an application by an incipient wetness impregnation) or their sequential release after decomposition of the coarse additive (in the case of mechanical activation). According to the BET analysis, it has been established that the change in the temperature of volatile compounds release Δtd is in direct correlation with the pore volume of the modified sample particles. [ABSTRACT FROM AUTHOR]

Fly ash as the name signifies is made from fly ash generated from the thermal power stations along with lime and gypsum. Pulverized fuel ash is called fly ash and is mostly generated from thermal power stations where it is generated by burning of coal. Almost 25-30% less cement or motor the fly ash bricks must require. Immense strength and bonding these bricks are made from machines easily arranged in symmetrical structures providing, hence, they are uniform in shape and size. These bricks absorb significantly less water the outside cement wall plastering is not required in case of fly ash bricks as they are grey and have smooth and uniform texture. These are much lighter in weight as compared to conventionally used red bricks thereby reducing the transportation and dead building costs. Moreover, such as fly ash bricks do not require firing which is an important manufacturing step for the red bricks and therefore does not contribute to environmental pollution. [ABSTRACT FROM AUTHOR]

Indonesia has abundant coal resources. However, some of the coal is difficult to be mined because of its location. Some are too far below the soil surface, or also called Deep Seated Coal (DSC). Underground Coal Gasification (UCG) is an alternative Clean Coal Technology that carried out gasification underground, thus it may have a potential explore DSC. The primary assessment of underground gasification may be started from a simple thermal analysis. This paper presents those assessment on the characteristics of gasification for further prospects of underground coal gasification implementation in Indonesia. The gasification experiments were carried out in a Thermogravimetric Analyser by using ten samples of coal from various locations in Indonesia. The experimental parameters include gasification media (CO2 or air) at temperature ranges from 35°C to 900°C and a heating rate of 10°C/min. The gasification media is passed at a rate of 100mL/min. Data of weight loss of sample were obtained from this experiment. From the experimental results, Arrhenius constants obtained on gasification with air are in the range 55643 to 114245 min−1 with the activation energy of 46.26 to 96.98 kJ/mol. Meanwhile, the gasification with CO2 yields Arrhenius constant 15301 up to 61339 min−1 and the activation energy of 12.72 to 109.71 kJ/mol. Those kinetics data provide the basic information for further exploring the possibility of underground coal gasification. [ABSTRACT FROM AUTHOR]