Features of the crystallization of AlCl3·6H2O in the system AlCl3 – MeClx – HCl – H2O

A laboratory setup has been developed to study the regularities of crystallization of aluminium chloride hexahydrate from hydrochloric acid solutions. The influence of the AlCl3 content in the initial solution, the consumption of gaseous HCl, and the behavior of impurities on the crystallization of AlCl3·6H2O from aluminium chloride solutions of leaching cinder obtained as a result of chlorinating ash burning from thermal power plants in Kazakhstan have been studied. The behavior of impurity metals in the process of crystallization of aluminium chloride solution has been studied, and their distribution between the products of the crystallization process has been established. It is shown that aluminium chloride content in the solution decreases with an increase in the consumption of hydrochloric acid. It was found that under the conditions of crystallization of AlCl3·6H2O, all impurities, except for barium, pass by 98% into the mother liquor. To reduce barium and other impurities in the obtained crystals of AlCl3·6H2O, it is proposed to carry out multiple washing of the crystals with hydrochloric acid (32% HCl). It has been shown that a decrease in the acidity of the washing solution from pH = 10 to pH = 5.5 ensures the isolation of ACH crystals with a minimum content of impurity metals, ppm: 3-5 Ca; 3-6 Fe; 1-3 Mg; 0.1-0.5 Ti; 1-3 Na; 20-30 P2O5. The moisture content of the obtained crystals is 4-5%; the particle size is 400-900 microns. As a result of mathematical processing, regression equations were constructed that adequately predict aluminium chloride content in the solution and its extraction into crystalline hydrate, depending on the consumption of hydrochloric acid. The optimal parameters of the crystallization process have been established: Т = 60 ºС, HCl concentration in the solution - 26-30%, HCl gas consumption = 0.5 l/min, duration 1 hour.

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Effect of Rice Husk Ash and Fly Ash on the workability of concrete mixture in the High-Rise Construction

E3S Web of Conferences ◽

10.1051/e3sconf/20183302029 ◽

2018 ◽

Vol 33 ◽

pp. 02029 ◽

Cited By ~ 10

Author(s):

Lam Van Tang ◽

Boris Bulgakov ◽

Sofia Bazhenova ◽

Olga Aleksandrova ◽

Anh Ngoc Pham ◽

...

Keyword(s):

Fly Ash ◽

Rice Husk ◽

Urban Areas ◽

Power Plants ◽

Thermal Power ◽

Concrete Mixture ◽

Regression Equations ◽

Humid Climate ◽

High Rise ◽

Concrete Mixtures

The dense development of high-rise construction in urban areas requires a creation of new concretes with essential properties and innovative technologies for preparing concrete mixtures. Besides, it is necessary to develop new ways of presenting concrete mixture and keeping their mobility. This research uses the mathematical method of two-factors rotatable central compositional planning to imitate the effect of amount of rice husk (RHA) and fly ash of thermal power plants (FA) on the workability of high-mobility concrete mixtures. The results of this study displays regression equation of the second order dependence of the objective functions - slump cone and loss of concrete mixture mobility due to the input factors - the amounts RHA (x1) and FA (x2), as well as the surface expression image of these regression equations. An analysis of the regression equations also shows that the amount of RHA and FA had a significant influence on the concrete mixtures mobility. In fact, the particles of RHA and FA will play the role as peculiar "sliding bearings" between the grains of cement leading to the dispersion of cement in the concrete mixture. Therefore, it is possible to regulate the concrete mixture mobility when transporting fresh concrete to the formwork during the high-rise buildings construction in the hot and humid climate of Vietnam. Although the average value of slump test of freshly mixed concrete, measured 60 minutes later after the mixing completion, decreased from 18.2 to 10.52 cm, this value still remained within the allowable range to maintain the mixing and and the delivery of concrete mixture by pumping.

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Determination of dependencies of dehydration of thermal power plants’ ash and slag waste from equipment parameters

E3S Web of Conferences ◽

10.1051/e3sconf/201910900015 ◽

2019 ◽

Vol 109 ◽

pp. 00015

Author(s):

Valentyna Cholyshkina ◽

Serhii Kostyria

Keyword(s):

Power Plants ◽

Thermal Power ◽

Raw Material ◽

Thermal Power Plants ◽

Regression Equations ◽

Processing Technologies ◽

New Device ◽

Ash And Slag Waste ◽

Nonlinear Character ◽

Slag Waste

Complex processing of ash and slag from coal-fired thermal power plants attracts a lot of attention. Waste processing will reduce the load on existing storage facilities, to return unburned coal to the boilers of power plants, to obtain a valuable raw material resource for construction, ferrous and non-ferrous metallurgy. At all thermal power plants of Ukraine utilization and storage of ash and slag is carried out by hydraulic method. Therefore, for all processing technologies relevant the dehydration of fine-disperse raw material. The article presents the results of laboratory tests of a new device for dehydration of ash and slag waste. It uses a set of influences on raw material: the overlay of vibration oscillations, the electric field and vacuumizing. By the method of pair linear correlations it is obtained that the dependence of moisture on each of the variable parameters has a weak nonlinear character. The exact and approximate multiple regression equations for the practical assessment of moisture under the combined action of all variable factors are obtained. With the size of the raw material + 0.63 – 0.05 mm, it allows to reduce the moisture from 30 to 9 %.

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Predictive Modeling of Integrated Boiler Unit for a Coal Fired Thermal Power Plant

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2016-0189 ◽

2017 ◽

Vol 18 (3) ◽

Author(s):

Sreepradha Chandrasekharan ◽

Rames Chandra Panda ◽

Bhuvaneswari Natrajan Swaminathan

Keyword(s):

Power Plant ◽

Thermal Power Plant ◽

Power Plants ◽

Thermal Power ◽

Electrical Energy ◽

Analysis Tool ◽

Regression Equations ◽

Boiler Unit ◽

Super Heater ◽

Statistical Analysis Tool

AbstractMajority of the power plants in the world is based on coal. Pulverized coal is used to generate pressurized steam to drive turbines where-by chemical energy is converted to electrical energy. Modeling of the steam generator in thermal power plant plays a major role as it comprises of interactive units like economizer, drum and super-heater. Experiments across different units of the power plant are carried out to build correlations between input and output. Main objective of the work is to compare performances arising out by considering the system-model as three individual units or as one integrated boiler unit. In order to do this, multiple regression equations are derived based on quadratic models. The dependability of the pressure and temperature on the other variables are analyzed using the statistical analysis tool and validation of the derived model with the plant data is performed. Significance of regressions were evaluated based on ANOVA which in combination with standardized residuals distribution and their means for confidence levels of 95 and 99 %, helped in validating the model. Operating parameters are optimized using RSM supported by design of experiments with Box-Behnken design. These models will be helpful in understanding and designing the safe operation and control of thermal power plants.

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Greenhouse Gas Emissions from Hydropower Reservoirs

Hydro Nepal Journal of Water Energy and Environment ◽

10.3126/hn.v11i0.7159 ◽

2012 ◽

Vol 11 ◽

pp. 37-42 ◽

Cited By ~ 7

Author(s):

Amit Kumar ◽

M.P. Sharma

Keyword(s):

Water Quality ◽

Greenhouse Gas ◽

Power Plants ◽

Thermal Power ◽

Linear Equations ◽

Quality Parameters ◽

Regression Equations ◽

Combined Impact ◽

The Impact ◽

Hydropower Reservoirs

Hydropower reservoirs are found to emit about 35-70 times less greenhouse gas (GHG) compared to thermal power plants. The emissions not only depend on the type of eco-region in which the reservoir is located but also on the reservoir characteristics and water quality parameters. This paper reports the results of the impact of reservoir parameters and water quality characteristics on GHG emission from tropical, temperate and boreal reservoirs. For this purpose, linear equations are developed but the regression coeffi cient is found very poor. The R2 range for CO2 is 5×10-5 to 0.36 for tropical, temperate and boreal reservoirs and the R24 is 0.004- 0.244 respectively, which is far lower than 0.90, and cannot be accurately used for prediction. Thereafter, empirical regression equations are developed to see the combined impact of reservoir parameters and R2 is found as 0.48 for CO2 and 0.16 for CH4 for tropical, 0.34 and 0.37 for CO2 and CH4 respectively for temperate and 0.51 and 0.26 for boreal reservoirs. The R2 0.90 indicates that these equations cannot be used to accurately predict the emissions, but can be used to get some idea about emissions from the reservoirs.DOI: http://dx.doi.org/10.3126/hn.v11i0.7159 Hydro Nepal Vol.11 2011 pp.37-42

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A Review on Utilization of Fly- Ash and Pond-Ash as a Partial Replacement of Cement in Concrete Mix Design

International Journal of Scientific Research in Science Engineering and Technology ◽

10.32628/ijsrset196270 ◽

2018 ◽

pp. 413-418

Author(s):

Harshkumar Patel ◽

Yogesh Patel

Keyword(s):

Fly Ash ◽

Electricity Generation ◽

Power Plants ◽

Renewable Energy Sources ◽

Thermal Power ◽

Strength Test ◽

Partial Replacement ◽

Pond Ash ◽

Research Activities ◽

Ash Disposal

Now-a-days energy planners are aiming to increase the use of renewable energy sources and nuclear to meet the electricity generation. But till now coal-based power plants are the major source of electricity generation. Disadvantages of coal-based thermal power plants is disposal problem of fly ash and pond ash. It was earlier considered as a total waste and environmental hazard thus its use was limited, but now its useful properties have been known as raw material for various application in construction field. Fly ash from the thermal plants is available in large quantities in fine and coarse form. Fine fly ash is used in construction industry in some amount and coarse fly ash is subsequently disposed over land in slurry forms. In India around 180 MT fly is produced and only around 45% of that is being utilized in different sectors. Balance fly ash is being disposed over land. It needs one acre of land for ash disposal to produce 1MW electricity from coal. Fly ash and pond ash utilization helps to reduce the consumption of natural resources. The fly ash became available in coal based thermal power station in the year 1930 in USA. For its gainful utilization, scientist started research activities and in the year 1937, R.E. Davis and his associates at university of California published research details on use of fly ash in cement concrete. This research had laid foundation for its specification, testing & usages. This study reports the potential use of pond-ash and fly-ash as cement in concrete mixes. In this present study of concrete produced using fly ash, pond ash and OPC 53 grade will be carried. An attempt will be made to investigate characteristics of OPC concrete with combined fly ash and pond ash mixed concrete for Compressive Strength test, Split Tensile Strength test, Flexural Strength test and Durability tests. This paper deals with the review of literature for fly-ash and pond-ash as partial replacement of cement in concrete.

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