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Research and Development of a Special Slag Glass Ceramics
Baowei Li,
Ming Zhao,
Yongsheng Du,
Hua Chen,
Jing Gao,
Hongxia Li,
Xiaolin Jia
Issue:
Volume 3, Issue 3, June 2018
Pages:
53-63
Received:
6 June 2018
Accepted:
25 June 2018
Published:
25 July 2018
Abstract: This paper is a thorough summary of the main results of the research group of the current authors, i.e. Research Group of Mining & Metallurgy Wastes Green-utilization with High-added Value, on developing glass ceramics of pyroxene system using Bayan Obo mine tailing and the fly ash from a Baotou thermal power plant as the main starting materials. The fabricating procedure and the typical properties were reported firstly. Then the primary effects of iron, lanthanum, cerium, niobium oxides and microwave sintering were examined respectively. Several important phenomena discovered during the research were analyzed. Based on these discoveries, the reason to the general good properties this special glass ceramic characterized by high hardness and bending strength, strong resistances to erosion and corrosion of acid and alkaline solutions was revealed. The result of the current study can serve as an example for the future utilization of solid wastes from mining, metallurgy and other relevant industries in a more profitable way and for the protection of both environment and natural resources.
Abstract: This paper is a thorough summary of the main results of the research group of the current authors, i.e. Research Group of Mining & Metallurgy Wastes Green-utilization with High-added Value, on developing glass ceramics of pyroxene system using Bayan Obo mine tailing and the fly ash from a Baotou thermal power plant as the main starting materials. T...
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Surface Alloying of the Casting in the Casting Mold
Rasulov Fuzuli,
Babaev Agil
Issue:
Volume 3, Issue 3, June 2018
Pages:
64-73
Received:
16 July 2018
Accepted:
6 August 2018
Published:
29 August 2018
Abstract: The article discusses the possibility of obtaining a composite coating on the surface of iron castings in the process of melt molding. As the composite powder mixture to the mold surface spreads used alloy powders and nickel-based low-alloyed white cast iron. Particle size distribution of these powders meet the following fractions: + 50-63; + 63-100; + 100-160; + 160-200; + 200-315 μm. It is established that a decrease in the thickness of the powder coating to 3-5mm casting of cast iron into a mold with powder spread at 1420-1440°C and the dispersion of the powder particles 50... 100 μm contribute to the formation of quality castings with a composite coating low-alloyed chrome-nickel white cast iron - gray cast iron and "nickel alloy CrNi80Si2B2 - gray cast iron". The increase in the casting temperature of cast iron from 1340°C to 1440°C increases the impregnation depth of the spread on the basis of the powder from low-alloyed chrome-nickel white cast iron and CrNi80Si2B2 by 3-4 mm. It is found that by forming the composite coating on the surface of the mechanical properties and corrosion resistance of the castings are significantly increased compared to bare casting for the same composition. It has been established that the σB and HB of the material of the "CrNi80Si2B2 - gray cast iron" composite coating in comparison with cast iron increases in 1.86-1.94 and 1.20-1.24 times, wear resistance - by 1.5 times, and corrosion resistance in 43 times; for the material "low-alloyed chrome-nickel white cast iron - gray cast iron" these figures improve 1.44 times and 2.55 times, wear resistance 5.6 times and corrosion resistance 4.25 times. Optimum technological parameters for manufacturing of cast-iron castings with a composite coating "powder nickel alloy CrNi80Si2B2 - gray cast iron Class 20" with the raised wear resistance, corrosion resistance and durability are recommended. Technological processes have been developed for the manufacture of castings with a composite coating - type bushings and parts of cast-iron valves.
Abstract: The article discusses the possibility of obtaining a composite coating on the surface of iron castings in the process of melt molding. As the composite powder mixture to the mold surface spreads used alloy powders and nickel-based low-alloyed white cast iron. Particle size distribution of these powders meet the following fractions: + 50-63; + 63-10...
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Electricity Generation Potential Through Solar-Rice Husk Hybrid Power Plant in Nepal and Its Major Paddy Producing Districts
Ram Dayal Yadav,
Ajay Kumar Jha,
Nawraj Bhattarai
Issue:
Volume 3, Issue 3, June 2018
Pages:
74-87
Received:
27 August 2018
Accepted:
17 September 2018
Published:
15 October 2018
Abstract: Nepal is an agricultural based country having huge potential of rice husk. Out of total electrical energy consumption in Nepal, 22%, 34.76% and 36.58% were imported from India in the years 2016, 2017 and 2018 respectively. Such import can be minimized by generating electricity from solar-rice husk hybrid system. Solar plants have drawbacks of intermittency in day/night cycle and reduced irradiation in winter and cloudy days. Biomass plants have problem associated with continuous supply of seasonal fuel. Those problems can be solved using hybrid system by maximizing the energy potential of these resources, increasing process efficiency, providing greater security of supply and reducing overall cost. The objective of this paper is to estimate electricity generation potential through solar- rice husk hybrid power plant in Nepal and its major paddy producing districts through existing data and forecasting the same for future potential. From existing data, the rice husk growth rate in Nepal was found to be 2.92% and on the basis of that growth rate, future potentials were forecasted. The 20 major paddy producing districts were taken into consideration as 71.15% of total paddy production of Nepal was found to be shared by those districts. The quantity of rice husk was found assuming 20% of paddy converted into rice husk in the mills. The rice husk consumption for cattle feeding was assumed 10% of total rice husk. The electric power from rice husk was calculated assuming 1.3 kg consumption of rice husk for per kWh generation of electricity through steam route and 1.86 kg of rice husk consumption for per kWh electricity generation through gasification route. The average increase rate of land for paddy production and the average increase rate of rice husk production were found to be 0.39% and 2.92% respectively. The electrical energy potentials of Nepal for the years 2015 and 2030 with solar-rice husk hybrid power plant through steam route were found as 100.67 MW and 155.02 MW respectively and through gasification route 70.36 MW and 108.35 MW respectively. The electrical potential for Jhapa district was found the highest values of 7.10 MW and 10.94 MW through steam route and 4.96 MW and 7.64 MW through gasification route for the years 2015 and 2030 respectively. Thus, through solar-rice husk hybrid power plant system, large amount of electricity can be generated locally in Nepal, which in turn can reduce energy import and enhance the better life of the people.
Abstract: Nepal is an agricultural based country having huge potential of rice husk. Out of total electrical energy consumption in Nepal, 22%, 34.76% and 36.58% were imported from India in the years 2016, 2017 and 2018 respectively. Such import can be minimized by generating electricity from solar-rice husk hybrid system. Solar plants have drawbacks of inter...
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Acoustic Performance of Parallel Baffled Silencers Different Configurations in HVAC Channel
Antonio Petosic,
Sanja Grubesa,
Mia Suhanek,
Ivan Djurek
Issue:
Volume 3, Issue 3, June 2018
Pages:
88-96
Received:
27 August 2018
Accepted:
7 September 2018
Published:
27 October 2018
Abstract: Serious noise pollution is one of the most unwanted consequences of the rapid urbanization and industrialization and various studies have shown that long exposure to noise can result in different health issues. Therefore, the performance of large industrial baffled silencer is crucial for reducing the environmental noise from large industrial plants. In this particular research the acoustic parameters of several different configurations of parallel baffled silencers have been compared by using an in-situ measurement method according to the ISO-11820:1996 Standard. The geometrical parameters e.g. length, thickness and distance between baffles as well as the absorption parameters of baffles have been changed in terms of full absorption and half-absorption surface. Furthermore, their influence on the silencer performance in channel with and without flow has been measured. Transmission and insertion loss acoustic parameters in octave frequency bands from 63 Hz up to 16 kHz are determined in the in-situ measurement setup including the influence of the reflections from baffles at the inlet side and opening at the outlet side. Moreover, the analytical expression (Piening and trapezoidal equation) for one parallel baffled silencer’s configuration has been compared with the measurement values on octave bands of interest. Additionally, the sound pressure distribution between baffles has also been measured and it can be concluded that the sound pressure level change is much larger at the beginning when compared to the value at the end of a silencer.
Abstract: Serious noise pollution is one of the most unwanted consequences of the rapid urbanization and industrialization and various studies have shown that long exposure to noise can result in different health issues. Therefore, the performance of large industrial baffled silencer is crucial for reducing the environmental noise from large industrial plant...
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