Reducing Greenhouse Emissions from Lignite Power Generation by Improving Current Drying Technologies

This study is an inventory analysis and environmental life cycle assessment of hotel food waste management that seeks to inform efforts towards the development of bio circular economy in Zimbabwe. An audit of food waste generation and an inventory analysis of the prevailing food waste management practices at three selected hotels was undertaken. The greenhouse gas emissions from the prevailing disposal of food waste at dumpsites and the proposed biological treatment of food waste were evaluated using the Tier 1 FOD method and Tier 1 method of biological treatment using the 2019 refined 2006 Intergovernmental Panel on Climate Change guidelines. Environmental life cycle assessment was also conducted for the open dumping, composting, and anaerobic digestion. The average food waste generation within the Zimbabwean hospitality industry was estimated at 1.63 kg/guest/day, with a minimum and maximum of 1.01 and 2.25 kg/guest/day, respectively. Source-separated food waste is currently being collected indiscriminately by municipal waste collection trucks for final disposal at the official landfills or dumpsites. This calls for the need for an offtake system of the source-separated food waste in the form of composting or anaerobic digestion. Study results showed that the disposal of food waste at solid waste disposal sites contributes to the highest greenhouse gas emissions, followed by composting with a 75% reduction in greenhouse emissions. Anaerobic digestion brings about a maximum reduction in greenhouse emissions of 97%. Environmental life cycle assessment results also show that anaerobic digestion is the best method leading to net negative environmental impacts.

Purpose. To calculate the parameters of the development of brown coal deposits, including the limiting overburden ratio, when involving coal clay into the development together with brown coal in the composition of the coal mass. Methodology. To calculate the cost of mining a mineral, the method of financial and mathematical averaged costs was applied, considering the level of projected capital investments and the cost of investment funds. Findings. The influence of the involvement of coal clays in the development together with brown coal as a part of coal mass on the limiting overburden ratio is investigated. It is determined that the limiting overburden ratio for a mining enterprise that extracts brown coal is 20 m3/t, and for the extraction of coal clay in a mixture with raw brown coal 17 m3/t. The parameters of brown coal production in Novo-Dmytrivske deposit have been established, which have shown that with a coal production of 9 million tons/year, the overburden ratio is 4 m3/t. In the case of extraction of associated minerals in the form of coal clays, the opencast capacity can increase up to 20 million tons/year, and the overburden ratio will decrease down to 1 m3/t. Originality. The dynamics of the change in the current overburden ratio over the years for the extraction of coal mass with the share of coal clays from 0 to 50% for the conditions of Novo-Dmytrivske brown coal deposit has been established. The costs to produce raw coal have been determined in terms of both natural and conventional fuel. The modelling of the costs for the extraction of minerals and rock mass, depending on the overburden ratio, has been carried out. The change in the overburden ratio was determined when coal clay and off-quality brown coal were involved in the production in comparison with the production of raw brown coal. Practical value. It has been established that those deposits and areas that were previously related to the development of the mine method or open-pit mines with large losses of coal during the complex mining of conditional seams of raw brown coal, off-quality seams, and coal clays, can potentially be mined with minimal losses of useful fossil and with low cost.

Lighting is an indispensable energy end use of man. A significant number people in developing countries live without electric lighting and depend on oil-based lamps. Globally, lighting consumes substantial amount of energy and is a major contributor to green house emissions. Conventional electric lighting systems such as incandescent lamps are highly inefficient and waste energy while the fluorescent/CFL lamps contain toxic chemicals like mercury. Incandescent lamps with short lifespan as well as the fluorescent/CFL lamps pose environmental waste disposal problems (e.g.). The use of renewable energy resource such as solar and wind power systems for example as sources of power for the most efficient and long life lighting source such as high-brightness light emitting diodes (LEDs) (also known as solid state lighting) would reduce global energy consumption for lighting by half, with corresponding reduction in green house emissions. In developing countries solar powered solid state lighting (SPSSL) would ensure access to electric lighting by the disperse population who may not be connected to the national grid in the near feature. In this article we elaborately review the upcoming solid state lighting technology. The physics and principles of operation of LEDs are also reviewed. The impact of this new lighting technology on developing countries in the areas of commerce, education, health and environmental impacts in comparison to conventional lighting technologies is the main thrust of this review.

Study on the economics of wind energy through cryptocurrency

Taking raw coal of China as the investigation object, MIPS method was used to calculate the material input of raw coal in the period of 1990~2008. Numerical calculation indicated that, in the production of raw coal, water input accounted for above 72% of the total material input, and solid non-biological material input accounted for about 25%, while air input accounted for only 0.4%. As for the whole country, the average input coefficients for water, solid non-biological material, and air were 6.13 t/t, 2.13 t/t, and 0.03 t/t, respectively; the average input coefficients for water, solid non-biological material, and air were 6.07 t/t, 2.26 t/t, and 0.03 t/t, respectively, for the state-owned major coal mines; in the local mine, the average input coefficients for water, solid non-biological material, and air were 6.17 t/t, 2.03 t/t, and 0.03 t/t, respectively. The raw coal material input as a whole appeared to be rising.

Seasonal thermodynamic prediction of the performance of a hybrid solar gas-turbine power plant

Triboelectrostatic separation of pulverized fuel of coal power plant based on mineralogical analyses

More than a fifth of the greenhouse emissions produced worldwide come from the transport sector. Several initiatives have been developed over the last few decades, aiming at improving vehicles’ energy conversion efficiency and improve mileage per liter of fuel. Most recently, electric vehicles have been brought back into the market as real competitors of conventional vehicles. Electric vehicle technology offers higher conversion efficiencies, reduced greenhouse emissions, low noise, etc. There are, however, several challenges to overcome, for instance: improving batteries’ energy density to increase the driving range, fast recharging, and initial cost. These issues are addressed on this chapter by looking in depth into both conventional and non-conventional storage technologies in different transportation applications.

Detailed mineralogical information from underground coal gasification (UCG) is essential to better understand the chemical reactions far below the surface. It is of great scientific significance to study the mineral transformation and identify the typical minerals in certain process conditions, because it may help to ensure the stable operation of gasification processes and improve the utilization efficiency of coal seams. The transformation of iron-bearing minerals has the typical characteristics during the UCG process and is expected to indicate the process parameters. In this paper, UCG progress was subdivided into pyrolysis, reduction and oxidation stages, and the progressive coal conversion products were prepared. Two types of lignite with different iron contents, Ulankarma and Ulanqab coals, were used in this study. The minerals in the coal transformation products were identified by X-ray diffraction (XRD) and a scanning electron microscope coupled with an energy-dispersive spectrometer (SEM-EDS). The thermodynamic calculation performed using the phase diagram of FactSage 7.1 was used to help to understand the transformation of minerals. The results indicate that the transformation behavior of iron-bearing minerals in the two lignites are similar during the pyrolysis process, in which pyrite (FeS2) in the raw coal is gradually converted into pyrrhotite (Fe1−xS). In the reduction stage, pyrrhotite is transformed into magnetite (Fe3O4) and then changes to FeO. The reaction of FeO and Al2O3 in the low iron coal produces hercynite above 1000 °C because of the difference in the contents of Si and Al, while in the high iron coal, FeO reacts with SiO2 to generate augite (Fe2Si2O6). When the temperature increases to 1400 °C, both hercynite and augite are converted to the thermodynamically-stable sekaninaite.

In coal production, the raw coal contains a large amount of gangue, which affects the quality of coal and pollutes the environment. Separating coal and gangue can improve coal quality, save energy, and reduce consumption and make rational use of resources. The separated gangue can also be reused. Robots with computer vision technology have become current research hotspots due to simple equipment, are efficient, and create no pollution to the environment. However, the difficulty in identifying coal and gangue is that the difference between coal and gangue is small, and the background and prospects are similar. In addition, due to the irregular shape of gangue, real-time grasping requirements make robot control difficult. This paper presents a coal and gangue separating robot system based on computer vision, proposes a convolutional neural network to extract the classification and location information, and designs a robot multi-objective motion planning algorithm. Through simulation and experimental verification, the accuracy of coal gangue identification reaches 98% under the condition of ensuring real-time performance. The average separating rate reaches 75% on low-, medium-, and high-speed moving conveyor belts, which meets the needs of actual projects. This method has important guiding significance in detection and separation of objects in complex scenes.

Coal preparation can remove most of the impurities in raw coal, reduce ash, and improve coal quality. Reducing the ineffective transportation of vermiculite, reducing the environmental pollution caused by burning coal, and providing the basic guarantee for the further clean and efficient use of coal are the foundation of clean coal technology. The domestic status of the automation technology of the coal preparation plant is introduced, and the issues needing attention in the automation technology of the coal preparation plant in China are introduced. Briefly describe the main contents of the current coal preparation plant automation technology and the issues needing attention in the control loop, and the possible consequences of an unreasonable design of the coal preparation plant automation system. By analyzing the development trend of the automation technology of the coal preparation plant, the broader development prospects of optimal control and video surveillance substation technology are expected. The scientific development of the coal preparation plant is to make full use of advanced coal preparation technologies, processes and equipment, improve the raw coal selection rate, continuously improve and improve the process, develop and introduce new efficient and high-yield washing equipment, and improve automation, professionalism, and informationization. And intelligence

Concrete is considered as a strong and durable construction material lasting over a century. Reinforced concrete is one among the most popular materials used for construction around the world. reinforced concrete is subjected to deterioration in harsh environment like costal regions therefore, sereveral researchers are striving hard with their efforts towards developing a new material to overcome this problem. This research investigates the utilization of marble dust powder in concrete, where marble A Green cement is a revolutionary topic in the history of cement Industry. This was first invented in Denmark in the year 1998.It presents the feasibility of the usage of By product materials like Flyash, GGBS(Ground granulated blast furnance slag),Graintedust. The use of Flyash in cement contributes the reduction of green house emission with negative impacts on the economy .It has been observed that 0.9tons of CO2 is produced per ton of cement production. It accounts for around 5% of world’s CO2 emission. it avoids the pollution and resue the materials the present study is carried out. Green cement reduces the shrinkage, creep, less heat of hydration and better workability and it requires less energy for its production ,Green cement is used in construction of bridges, buildings, dams and roads.

The present paper deals with the optimal planning for blending of coal of different grades for beneficiation of coal with a view to satisfy the requirements of the end users with desired specifications. The input specifications are known whereas aspiration levels of the characteristics washed coal have been specified. Beneficiation of coal refers to the production of wash coal from raw coal with the help of some suitable beneficiation/coal washing technologies. The processed coal is used by the different steel plants to serve their purpose during the manufacturing process of steel. The aim is to fix the level of the raw coal samples from different coal seams to be used/fed for the beneficiation to meet the desired target of the coal blending indicators, yield to maximum extent and to restrict the input cost of raw coal to be fed for beneficiation. The problem is considered as multi criteria decision making problem and solved using multi objective genetic algorithm. A case study from a regional coal company situated at Jharia coalfield, India has been made and solved using the proposed model.

The present review aims to provide an up-to-date summary of bio-methane (CH₄) gas production, which use as is a renewable energy source. Burned bio-methane gas used for water heating, space heating, drying, or cooking. CH₄ is also used in an automotive to produce both heat and electricity. The bio-methane gas is produced by anaerobic digestion (AD) technology of food waste, agricultural waste, municipal waste, green waste, manure, and sewage. AD technolog is promising technology; having the potential to convert several bio-masses into bio-gas rich with methane gas, which is alternative to fossil fuels. The hydrolysis, acidogenesis, acetogenesis, and methanogenesis are essential steps of AD process. The steps are proceeding by different kind of bacteria such as, acidogenic, acetogenic, and methanogenic bacteria. An effective process to increase the productivity of an anaerobic digestion process by combining it with a microbial electrosynthesis system (MES) was developed. Percentage compositions of CH₄ from anaerobic digestion of a different feedstock were between 50% - 84%. The various physical, chemical, physiochemical and, biological pretreatments methods were applied to break the complex biomass into easily digested components. The AD system has many advantages, like low energy consumption, low nutrient and chemical requirement, improved sanitation, pathogens reduction, reduction of disease transmission, greenhouse emissions and nitrous oxide emissions reduction, etc. And some of the anaerobic digestion disadvantages are a long start-up, high buffer requirements for pH controlling, higher sensitivity of microorganisms to pH and temperature, etc. More advantages and disadvantages are discussed in this review. In the future, will be solutions to problems that limits production yield.

Biofuels are an important tool for the reduction of carbon dioxide and other greenhouse emissions. NAD+-dependent formate dehydrogenase has been previously shown to be capable of the electrochemical reduction of carbon dioxide into formate, which can be ultimately converted to methanol. We established that a functional enzyme, tagged for immobilization, could be continuously secreted by Pichia pastoris. The protein can be easily separated from the growth media and its activity remains constant over an extended period of time. This is an important first step in creating a self-sustaining system capable of producing biofuels with minimal resources and space required.