Economic and Environmental Assessment of Redmud as Aggregate in Cement Clinker Production

2011 ◽  
Vol 90-93 ◽  
pp. 3254-3257
Author(s):  
Jing Min Hong ◽  
Ling Wang ◽  
Jing Lan Hong

A cost combined life cycle assessment was carried out to estimate the economic and environmental impact of redmud as aggregate in cement production. Results showed that the raw materials, transport, electricity and coal had the highest contribution to overall cost, while coal production and direct emissions represented the dominant contribution to overall environment impact. Improving energy and raw material efficiency and minimizing raw materials transport distance are the efficient way to minimize overall environmental and economic impacts.

Author(s):  
Ali Benlamoudi ◽  
Aeslina Abdul Kadir ◽  
Mohamed Khodja

The objective of this study is to investigate the performance of incorporating petroleum sludge waste as raw materials into the cement clinker production. The burnability and the structural analysis of the produced clinker were studied. The results showed that the addition of petroleum sludge into the clinker matrices improved the burnability of the clinker by lowering the free lime content. Moreover, 2.5% and 5% of this waste was effective and did not affect the quality of the cement clinker negatively. This study, which is the first to investigate the incorporation of petroleum sludge into cement production, provides also a complete elimination of this waste from the environment.


2020 ◽  
Vol 24 (4) ◽  
pp. 36-41
Author(s):  
O.A. Miryuk

There are presented the results of physicochemical studies of the composition and thermal transformations og large-tonnage wastes of beneficiation of scarnified-magnetite ores from Kazakhstan. To determine the composition of materials and thermal transformations, the following methods were used: X-ray phase analysis, differential-thermal analysis, Mцssbauer and infrared spectroscopy. There was revealed the stepwise nature of the transformation of anthropogenic material during roasting, due to polymineral composition of ore beneficiation. It has been established that the chemical-mineral characteristics of natural silicates determine the formation processes and properties of clinker phases. An integrated approach to the study of technogenic raw materials allowed not only to substantiate the possibility and expedience of using scarnified-magnetite ore beneficiation wastes in cement production, but also to determine the preference for the phase composition of cement clinker. Research result from the basis for the development of low-energy cement clinkers with a high content of belite phase.


2005 ◽  
Vol 5 (2) ◽  
pp. 169
Author(s):  
Sumardi P ◽  
I. B. Agra ◽  
I. M. Bendiyasa ◽  
Wahyudi B. S.

Wahyudi B.S.Wahyudi B.S.In general, the main raw materials in Portland cement production are limestone, clay, and corrective materials such as iron sand and silica sand. These raw material come from natural deposits, which are very hard to find in some countries. In this research, Portland cement was made by utilizing the demolition rubble of office and housing buildings. The rubble consists of concrete wastes (mixtures of hydrated Portland cement minerals and some aggregates) and some building bricks as well as mortar/plaster of Portland cement. To meet the cement modulus, which is generally used in Portland cement industries, corrective materials such as limestone (source of CaO) and disposed building bricks are used. The term burning ability is used for Portland cement to measure the CaO free content in the cement clinker produced from specified raw material mixes at a specific operating 'condition of clinkering. The cement modulus used is Ume Saturation Factor (LSF) and Silica Modulus (SM). The minimum Cao free content was found by using LSF: 0.86, SM: 2.14, and clinkering temperature 14000C for 30 minutes. The cement modulus was made from concrete waste, limestone, and disposed red brick with a weight ratio of 1: 3.489: 0.677. Keywords: Burning ability,demolition rubble of buildings, Portland cement, and raw mixes.


2020 ◽  
Vol 10 (1) ◽  
pp. 49
Author(s):  
Suharto Suharto ◽  
Muhammad Amin ◽  
Muhammad Al Muttaqii ◽  
Syafriadi Syafriadi ◽  
Kiki Nurwanti

Experimental study on the use of basalt stone originated from Lampung has been conducted to evaluate its potential for a partial substitute of raw material in production of cement clinker. The basalt stone contains minerals of anorthite, augite, and albite phases that are required for clinker formation. In this study, the main raw materials were 80% limestone, 10% silica sand, 9% clay and 1% iron sand. The raw material in these experiments were mixtures 90% or 80% of the main raw material and 10% or 20% of basalt stone. The effect of adding coal to raw materials was also studied to see the possibility of an increase in clinkerization temperature inside the raw material mixture, and at the same time to see the effect of coal ash on clinker composition. Clinker obtained from heating of raw materials at a temperature of 1100oC had LSF of 94.1% and 95.1% (heating time of 1 and 3 hours). If heating is carried out at 1200oC, the clinker had LSF of 97.7% and 98.0% (heating time of 2 and 3 hours, respectively). Depending on the temperature and duration of heating, the clinker mostly had SM in the range of 2.18-2.40% , and AM in the range of 0,78-1.80%. Characterization using XRD showed that the clinker consisted of larnite and gehlenite phases, and dominated by CaO.Batu basalt Lampung telah diuji potensinya sebagai pengganti sebagian bahan baku utama pembuatan klinker semen. Batu basalt tersebut memiliki mineral-mineral dalam fase anorthite, augite, dan albite yang diperlukan pada pembentukan klinker. Pada penelitian ini, bahan baku utama adalah batu kapur 80%, pasir silika 10%, tanah liat 9% dan pasir besi 1%. Campuran bahan baku klinker adalah 90% atau 80% bahan baku utama dan 10% atau 20% batu basalt. Efek penambahan batubara ke dalam bahan baku klinker juga dipelajari untuk melihat kemungkinan kenaikan temperatur klinkerisasi di dalam campuran bahan baku, dan sekaligus untuk melihat efek abu batubara terhadap komposisi klinker. Klinker hasil pemanasan bahan baku pada temperatur 1100oC memiliki LSF 94,1% dan 95,1% (lama pemanasan 1 dan 3 jam). Jika pemanasan dilakukan pada 1200oC, klinker memilik LSF 97,7% dan 98,00% (lama pemanasan 2 dan 3 jam). Tergantung pada temperatur dan lama pemanasan, klinker hasil percobaan ini umumnya memiliki SM 2,18-2,40%, dan AM antara 0,78-1,80%. Karakterisasi dengan XRD menunjukkan bahwa klinker terdiri dari fase larnite dan gehlenite, dan didominasi CaO.


2020 ◽  
Vol 12 (6) ◽  
pp. 2500 ◽  
Author(s):  
Li Ping ◽  
Gang Zhao ◽  
Xiaohu Lin ◽  
Yunhui Gu ◽  
Wei Liu ◽  
...  

Cement manufacturing and the treatment of sludge are considered both energy-intensive industries and major greenhouse gas (GHG) emitters. However, there are still few studies on comprehensive carbon footprint analysis for adding municipal sludge in the cement production. In this study, the lime-dried sludge blended with calcium oxide at the mass mixing ratio of 10% was utilized as raw material for the preparation of Portland cement. The chemical and physical properties of sludge were analyzed. A set of carbon footprint calculation methods of lime-drying treatment of sludge and reuse in cement kilns was then established to explore the feasibility of coprocessing lime-dried sludge in cement kilns. The results showed lime-dried sludge containing CaO, SiO2, Al2O3, and Fe2O3 was ideal for cement production as raw material. However, the water content of lime-dried sludge should be strictly limited. The lime-drying process presented the biggest carbon emission (962.1 kg CO2-eq/t sludge), accounting for 89.0% of total emissions. In the clinker-production phase, the lime-dried sludge as raw material substitute and energy source gained carbon credit of 578.8 and 214.2 kg CO2-eq/t sludge, respectively. The sludge used for producing cement clinker could reduce carbon emissions by 38.5% to 51.7%. The addition ratio of lime and stacking time in the sludge lime-drying process could greatly affect the carbon footprint of coprocessing lime-dried sludge in cement kiln.


2013 ◽  
Vol 824 ◽  
pp. 490-498
Author(s):  
B. Kareem

Attainment of accuracy in raw materials mix for production processes has been the major problem in many production organizations in developing countries. Effects of unequal proportions of material required for a production process are not fully considered in the past studies. This study modeled the raw material requirements in a production process using proportionality based mixed linear programming approach. The objective was to find optimal mix of raw materials for the production of a unit tonnage of a product. The performance of the model was tested by comparing it with alternatively formulated model based on conventional material mix. This model was tested using a cement production system from which blasted limestone, crushed limestone; raw meal, gypsum, red alluvium, clinker and coal were used as raw materials. The conventional method of mixing materials led to 50 % surplus and shortage of materials in the process as compared with the new scheme. The model would be a good tool for accurate prediction of quantity of the raw material required in the production process.Nomenclature, the proportion of material used per ton of the processed product, the quantity of material in processed product (ton), the material proportional per ton of the product, andthe total quantity of materials needed per ton of the product,..., the counter for material type,..., the counter for material proportionality variant


2017 ◽  
Vol 24 (36) ◽  
pp. 27862-27869 ◽  
Author(s):  
Minrui Huang ◽  
Huajun Feng ◽  
Na Li ◽  
Dongsheng Shen ◽  
Yuyang Zhou ◽  
...  

2013 ◽  
Vol 389 ◽  
pp. 341-345 ◽  
Author(s):  
Ya Li Wang ◽  
Shi Jie Dong ◽  
Lin Lin Liu ◽  
Su Ping Cui ◽  
Hai Bo Xu

Calcium carbide Slag is one kind of industrial wastes from CaC2 hydrolysis reaction that will cause land pollution. In the research, calcium carbide Slag used as a substitute for limestone to produce cement clinker, which with a high portion of CaO content and then an excellent calcium containing raw material. As a kind of industrial wastes, the properties of Calcium carbide slag differentiate from that of natural limestone. The formation process of clinker minerals was studied by means of XRD. The results indicated that clinker minerals formation is similar to that from use of limestone. The generated clinker has a rational mineral composition and well developed mineral phase structure. But, there are many differences in decomposition temperatures between the calcium containing raw materials. Therefore, the carbide slag can be used as a substitute of limestone raw material to produce cement clinker.


2014 ◽  
Vol 629-630 ◽  
pp. 337-342
Author(s):  
Hong Mei Ai ◽  
Su Feng Zhu

Utilizing construction waste, mainly waste concrete, to produce recycled cement, provides possibility for realizing the closed circulation between concrete and cement, which is an effective way for sustainable development of cement and concrete industry. Waste clay brick (WCB) and its surface-coated waste mortar are inevitably introduced into the raw meals while waste concrete is used in cement production. So on the basis of the composition characteristics of construction waste, considering of optimizing the performance of recycled cement and improving the adaptability of recycled cement to complex raw material, it's necessary to study the effect of raw meal mixing waste concrete and WCB on sintering process and property of recycled cement clinker. Mixing waste concrete and WCB in three different proportions, the burnability of raw meal, clinker mineral composition, clinker mineral morphology and hydration characteristics of recycled cement have been studied in this paper. The results indicate, the presence of WCB is beneficial for the generation and development of silicate minerals; with increasing proportion of WCB, the content of f-CaO in recycled cement clinker rises, the structure of C-S-H gel from hydration product presents higher densification and the compression strength of 3d and 28d curing period are enhanced.


2021 ◽  
Vol 10 (1) ◽  
pp. 1-7
Author(s):  
Herliati Rahman ◽  
Akhirudin Salasa

Currently, the use of alternative fuels and raw materials (AFR) in the cement industry is very attractive. This is driven by demands for environmental sustainability and the efficiency of fuel and raw material costs. One of the materials that can be used as AFR is sludge oil. However, it needs to be ensured that the chlorine content in the sludge oil does not exceed the threshold so that it does not have a negative impact during the cement production process. It is known that if the chlorine content is more than the threshold, it can cause blocking or clogging of the separator and the kiln. This study aims to determine the performance of the Jena Multi EA 4000 instrument in determining the chlorine content in sludge oil quickly and accurately. Analytic Jena Multi EA 4000 is an Atomic Absorption Spectrometers (AAS) instrument that can be used for analysis of samples in the form of solids or slurries containing chlorine. As validation of the resulting analysis, the wet method is used, which as usual, to determine chlorine levels. From the statistic analysis, namely the F-test and T-test, We found that F-count equal to 0.0080 and F-table equal to 4.2839. it shows that F-count < F-table, indicating the difference in the variance of the two methods H0: s12 = s22 is accepted because there is no difference to the variability of these two tests and the value of T-count = -3.9717 and T-table = 2.1788 so that T-count <T-table is accepted because there is no difference in the average accuracy of the two methods H0: M1 = M2.  


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