The status of energy conservation in Taiwan's cement industry

International Nuclear Information System (INIS)

Su, Te-Li; Chan, David Yih-Liang; Hung, Ching-Yuan; Hong, Gui-Bing

2013-01-01

The cement industry represents one of the most energy intensive sectors in Taiwan. Energy audits are the direct tools which are employed to help reduce energy consumption. The objectives of energy audits are to establish energy audit systems, provide on-site energy audit service and reduce production cost. This study summarized the energy savings implemented in Taiwan's cement industry; the data were obtained from the on-line Energy Declaration System in 2010. The total implemented energy savings amounted to 68,512 kilo liter of crude oil equivalent (KLOE). The energy audit group audited seven Taiwanese cement plants in 2011 and revealed an energy saving potential of 2571.6 MWh of electricity and 1002.8 KLOE of thermal energy. The total potential energy saving was 1708.5 KL of crude oil equivalent (KLOE), equivalent to a 4560 t reduction in CO 2 emissions, representing the annual CO 2 absorption capacity of a 122 ha forest plantation. - Highlights: • This study summarizes the energy savings implemented in Taiwan's cement industry from the on-line Energy Declaration System. • The energy audit group audited seven Taiwanese cement plants in 2011 and revealed energy saving potential was 1708.5 KLOE. • This work aims to examine what Taiwan has done and also describes the current status in cement industry. • In addition, some potential energy conservation opportunities or measures are revealed in this paper

Analysis of energy-efficiency opportunities for the cement industry in Shandong Province, China: A case study of 16 cement plants

Energy Technology Data Exchange (ETDEWEB)

Hasanbeigi, Ali; Price, Lynn; Lu, Hongyou [China Energy Group, Energy Analysis Department, Environmental Energy Technologies Division, Ernest Orlando Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 90R4000, Berkeley, CA 94720 (United States); Lan, Wang [China Building Materials Academy, Guanzhuang, Chaoyang District, Beijing, Post code 100024 (China)

2010-08-15

In this study, 16 cement plants with New Suspension Preheater and pre-calciner (NSP) kiln were surveyed. Plant energy use was compared to both domestic (Chinese) and international best practice using the Benchmarking and Energy Saving Tool for Cement (BEST-Cement). This benchmarking exercise indicated an average technical potential primary energy savings of 12% would be possible if the surveyed plants operated at domestic best practice levels in terms of energy use per ton of cement produced. Average technical potential primary energy savings of 23% would be realized if the plants operated at international best practice levels. Then, using the bottom-up Electricity Conservation Supply Curve (ECSC) model, the cost-effective electricity efficiency potential for the 16 studied cement plants in 2008 is estimated to be 373 gigawatt-hours (GWh), and total technical electricity-saving potential is 915 GWh, which accounts for 16 and 40% of total electricity use in the studied plants in 2008, respectively. The Fuel Conservation Supply Curve (FCSC) model shows the total technical fuel efficiency potential equal to 7949 terajoules (TJ), accounting for 8% of total fuel used in the studied cement plants in 2008. All the fuel efficiency potential is shown to be cost effective. (author)

Energy efficiency technologies in cement and steel industry

Science.gov (United States)

Zanoli, Silvia Maria; Cocchioni, Francesco; Pepe, Crescenzo

2018-02-01

In this paper, Advanced Process Control strategies aimed at energy efficiency achievement and improvement in cement and steel industry are proposed. A flexible and smart control structure constituted by several functional modules and blocks has been developed. The designed control strategy is based on Model Predictive Control techniques, formulated on linear models. Two industrial control solutions have been developed, oriented to energy efficiency and process control improvement in cement industry clinker rotary kilns (clinker production phase) and in steel industry billets reheating furnaces. Tailored customization procedures for the design of ad hoc control systems have been executed, based on the specific needs and specifications of the analysed processes. The installation of the developed controllers on cement and steel plants produced significant benefits in terms of process control which resulted in working closer to the imposed operating limits. With respect to the previous control systems, based on local controllers and/or operators manual conduction, more profitable configurations of the crucial process variables have been provided.

Technical benefit and risk analysis on cement clinkering process with compact internal burning of carbon

International Nuclear Information System (INIS)

Chen, Hanmin

2015-01-01

This article demonstrates the potential technical benefit and risk for cement clinkering process with compact internal burning of carbon, a laboratory-phase developing technique, from 9 aspects, including the heat consumption of clinkering and exhaust heat utilization, clinker quality, adaptability to alternative fuels, the disposal ability of industrial offal and civil garbage, adaptability to the raw materials and fuels with high content of chlorine, sulphur and alkali, the feasibility of process scale up, the briquetting process of the coal-containing cement raw meal pellet, NO x emission and the capital cost and benefit of conversion project. It is concluded that it will be able to replace the modern precalciner rotary kiln process and to become the main stream technique of cement clinkering process in low carbon economy times. - Highlights: • Compact internal burning of carbon enables cement shaft kiln to run stably. • Compact internal burning of carbon enables cement shaft kiln to scale up. • New process triples energy efficiency with excellent environmental performance. • It will be able to compete with and replace the existing precalciner kiln process. • It will become the mainstream clinkering process in low carbon economy

A critical analysis of energy efficiency improvement potentials in Taiwan's cement industry

International Nuclear Information System (INIS)

Huang, Yun-Hsun; Chang, Yi-Lin; Fleiter, Tobias

2016-01-01

The cement industry is the second most energy-intensive sector in Taiwan, which underlines the need to understand its potential for energy efficiency improvement. A bottom-up model-based assessment is utilized to conduct a scenario analysis of energy saving opportunities up to the year 2035. The analysis is supported by detailed expert interviews in all cement plants of Taiwan. The simulation results reveal that by 2035, eighteen energy efficient technologies could result in 25% savings for electricity and 9% savings for fuels under the technical diffusion scenario. This potential totally amounts to about 5000 TJ/year, of which 91% can be implemented cost-effectively assuming a discount rate of 10%. Policy makers should support a fast diffusion of these technologies. Additionally, policy makers can tap further saving potentials. First, by decreasing the clinker share, which is currently regulated to a minimum of 95%. Second, by extending the prohibition to build new cement plants by allowing for replacement of existing capacity with new innovative plants in the coming years. Third, by supporting the use of alternative fuels, which is currently still a niche in Taiwan. - Highlights: •We analyze energy efficiency improvement potentials in Taiwan's cement industry. •Eighteen process-specific technologies are analyzed using a bottom-up model. •Our model systematically reflects the diffusion of technologies over time. •We find energy-saving potentials of 25% for electricity and 9% for fuels in 2035. •91% of the energy-saving potentials can be realized cost-effectively.

Energy economy and industrial ecology in the Brazilian cement sector

International Nuclear Information System (INIS)

Tavares, Marina Elisabete Espinho; Schaeffer, Roberto

1999-01-01

The article discusses the following issues of the Brazilian cement sector: the Brazilian cement main types specification, cement quantities evolution produced in Brazil from 1987 to 1997, energy conservation in the cement production process with additives, energy economy cost estimates from the utilization of additives, and several technologies energy economy cost used in the industrial sector

Industrial trial to produce a low clinker, low carbon cement

Directory of Open Access Journals (Sweden)

Vizcaíno-Andrés, L. M.

2015-03-01

Full Text Available A preliminary assessment of conditions for the industrial manufacture of a new cementitious system based on clinker-calcined clay and limestone, developed by the authors, referred as “low carbon cement” is presented. The new cement enables the substitution of more than 50% of the mass of clinker without compromising performance. The paper presents the follow-up of an industrial trial carried out in Cuba to produce 130 tonnes of the new cement at a cement plant. The new material proved to fulfill national standards in applications such as the manufacture of hollow concrete blocks and precast concrete. No major differences either in the rheological or mechanical properties were found when compared with Portland cement. Environmental assessment of the ternary cement was made, which included comparison with other blended cements produced industrially in Cuba. The new cement has proven to contribute to the reduction of above 30% of carbon emissions on cement manufacture.Se presenta la evaluación preliminar de las condiciones de fabricación industrial de un nuevo sistema cementicio a partir del empleo de clínquer; arcillas calcinadas y piedra caliza; desarrollado por los autores; denominado “cemento de bajo carbono”. El nuevo cemento posibilita la reducción de más de un 50% de la masa de clínquer; sin comprometer el comportamiento del material. El presente trabajo presenta el monitoreo de la producción industrial en una planta en Cuba; de 130 t del nuevo cemento. El cemento obtenido cumple con las regulaciones nacionales de calidad y su empleo tiene similar rendimiento que el cemento Pórtland para la producción de bloques y hormigón de 25 MPa. Se realiza el análisis de impacto ambiental del cemento ternario mediante la comparación con otros cementos producidos industrialmente. El nuevo cemento puede contribuir a la reducción de más del 30% de las emisiones de CO2 asociadas a la manufactura de cemento.

Carbon dioxide emissions and climate change: policy implications for the cement industry

International Nuclear Information System (INIS)

Rehan, R.; Nehdi, M.

2005-01-01

There is growing awareness that the cement industry is a significant contributor to global carbon dioxide (CO 2 ) emissions. It is expected that this industry will come under increasing regulatory pressures to reduce its emissions and contribute more aggressively to mitigating global warming. It is important that the industry's stakeholders become more familiar with greenhouse gas (GHG) emission and associated global warming issues, along with emerging policies that may affect the future of the industry. This paper discusses climate change, the current and proposed actions for mitigating its effects, and the implications of such actions for the cement industry. International negotiations on climate change are summarized and mechanisms available under the Kyoto Protocol for reducing greenhouse gas emissions are explained. The paper examines some of the traditional and emerging policy instruments for greenhouse gas emissions and analyses their merits and drawbacks. The applicability, effectiveness and potential impact of these policy instruments for the global cement industry in general and the Canadian cement industry in particular are discussed with recommendations for possible courses of action

Energy Efficiency Improvement Opportunities for the Cement Industry

Energy Technology Data Exchange (ETDEWEB)

Price, Lynn; Worrell, Ernst; Galitsky, Christina; Price, Lynn

2008-01-31

This report provides information on the energy savings, costs, and carbon dioxide emissions reductions associated with implementation of a number of technologies and measures applicable to the cement industry. The technologies and measures include both state-of-the-art measures that are currently in use in cement enterprises worldwide as well as advanced measures that are either only in limited use or are near commercialization. This report focuses mainly on retrofit measures using commercially available technologies, but many of these technologies are applicable for new plants as well. Where possible, for each technology or measure, costs and energy savings per tonne of cement produced are estimated and then carbon dioxide emissions reductions are calculated based on the fuels used at the process step to which the technology or measure is applied. The analysis of cement kiln energy-efficiency opportunities is divided into technologies and measures that are applicable to the different stages of production and various kiln types used in China: raw materials (and fuel) preparation; clinker making (applicable to all kilns, rotary kilns only, vertical shaft kilns only); and finish grinding; as well as plant wide measures and product and feedstock changes that will reduce energy consumption for clinker making. Table 1 lists all measures in this report by process to which they apply, including plant wide measures and product or feedstock changes. Tables 2 through 8 provide the following information for each technology: fuel and electricity savings per tonne of cement; annual operating and capital costs per tonne of cement or estimated payback period; and, carbon dioxide emissions reductions for each measure applied to the production of cement. This information was originally collected for a report on the U.S. cement industry (Worrell and Galitsky, 2004) and a report on opportunities for China's cement kilns (Price and Galitsky, in press). The information provided in

Reduction of environmental pollution through optimization of energy use in cement industries

Energy Technology Data Exchange (ETDEWEB)

Karbassi, A.R.; Jafari, H.R.; Yavari, A.R.; Hoveidi, H. [Univ. of Tehran (Iran). Graduate Faculty of the Environment; Sid Kalal, H. [J.I.H. Research Laboratories, Tehran (Iran). Nuclear Science and Technology Research Inst.

2010-01-01

Industrial development has lead to higher energy consumption, emission of greenhouse gases, as well as air pollutants. Cement factories play an important role in overall greenhouse emissions. This study aims to investigate the role of Iranian cement industries and their contribution of greenhouse gases contribution. The measured emission factors for oil and fuel gas shows that carbon dioxide contribution from fuel oil based cement industries is almost 2.7 times higher than gas based cement factories. The strength, weakness, opportunity and threat technique analysis showed that the best strategy to combat greenhouse gases from Iranian cement factory is to implement energy efficiency measures. Further, strategic position and action evaluation matrix analysis indicates that Iranian cement industries fall within invasive category. Therefore, exploitation of opportunities must carefully be used. One of these opportunities is the utilization of financial assistance provided by clean development mechanism. The results show that replacement of ball mills with vertical roller mill can reduce the electricity consumption from 44.6 to 28 kWh/ton. As a result of such substitution about 720 million kWh/y of electricity would be saved (almost a power plant of 125 MW capacities). Though implementation of new mills may not be economic for the cement industries' owner, but the overall gain for the government of Iran will be about US$ 304 million. If the duration of such efficiency measure is considered as about 12 y, then the overall carbon dioxide (CO{sub 2}) reduction/phase-out would be around 4.3 million tons.

Secondary fuels and raw materials in the Spanish cement industry

Energy Technology Data Exchange (ETDEWEB)

Gordobil, J.C.U.; Guede, Elena [Cementos Lemona s.a. (Spain)

1997-03-01

The growing environmental and energy concern are having an impact on the Spanish cement industry. This article describes the impact on waste management, the operation of cement kilns and the possibility for recycling. Current projects and future prospects are described. (UK)

Evaluating co-benefits of energy efficiency and air pollution abatement in China’s cement industry

International Nuclear Information System (INIS)

Zhang, Shaohui; Worrell, Ernst; Crijns-Graus, Wina

2015-01-01

Highlights: • Implementation rates of 37 EEMs are quantified for China’s cement industry. • Energy Supply Cost Curves were implemented in the GAINS model. • The economic energy saving potential is 3.0 EJ and costs is $4.1 billion in 2030. • Energy efficiency would lead to large reductions in air pollution. • The co-benefits decrease average marginal costs of EEMs by 20%. - Abstract: China’s cement industry is the world’s largest and is one of the largest energy consuming, and GHG and air pollutant emitting industries. Actions to improve energy efficiency by best available technology can often bring co-benefits for climate change and air quality through reducing emissions of GHGs and air pollutants emission. In this study, the energy conservation supply curves (ECSC) combined with the GAINS (Greenhouse Gas and Air Pollution Interactions and Synergies) was used to estimate the co-benefits of energy savings on CO 2 and air pollutants emission for implementing co-control options of energy efficiency measures and end-of-pipe options in the China’s cement industry for the period 2011–2030. Results show that there are large co-benefits of improving energy efficiency and reducing emissions of CO 2 and air pollutants for the China’s cement industry during the study period. The cost-effective energy saving potential (EEP1 scenario) and its costs is estimated to be 3.0 EJ and 4.1 billion $ in 2030. The technical energy savings potential (EEP2 scenario) and its costs amount to 4.2 EJ and 8.4 billion $ at the same time. Compared to the baseline scenario, energy efficiency measures can help decrease 5% of CO 2 , 3% of PM, 15% of SO 2 , and 12% of NOx emissions by 2030 in EEP1 scenario. If we do not consider costs (EEP2 scenario), energy efficiency measures can further reduce 3% of CO 2 , 2% of PM, 10% of SO 2 , and 8% of NOx by 2030. Overall, the average marginal costs of energy efficiency measures will decrease by 20%, from 1.48 $/GJ to 1.19 $/GJ, when

Co-controlling CO2 and NOx emission in China's cement industry: An optimal development pathway study

Directory of Open Access Journals (Sweden)

Xiang-Zhao Feng

2018-03-01

Full Text Available It is of important practical significance to reduce NOx emission and CO2 emission in China's cement industry. This paper firstly identifies key factors that influence China's future cement demand, and then uses the Gompertz model to project China's future cement demand and production. Furthermore, the multi-pollutant abatement planning model (MAP was developed based on the TIMES model to analyze the co-benefits of CO2 and NOx control in China's cement industry. During modeling analysis, three scenarios such as basic as usual scenario (BAU, moderately low carbon scenario (MLC, and radically low carbon scenario (RLC, were built according to different policy constraints and emission control goals. Moreover, the benefits of co-controlling NOx and CO2 emission in China's cement industry have been estimated. Finally, this paper proposes a cost-efficient, green, and low carbon development roadmap for the Chinese cement sector, and puts forwards countermeasures as follows: first, different ministries should enhance communication and coordination about how to promote the co-control of NOx and CO2 in cement industry. Second, co-control technology list should be issued timely for cement industry, and the R&D investment on new technologies and demonstration projects should be increased. Third, the phase-out of old cement capacity needs to be continued at policy level. Fourth, it is important to scientifically evaluate the relevant environmental impact and adverse motivation of ammonia production by NOx removal requirement in cement industry. Keywords: Cement industry, CO2 abatement, NOx reduction, Co-benefit analysis

Technical assessment of three layered cement-bonded boards produced from wastepaper and sawdust

International Nuclear Information System (INIS)

Fuwape, Joseph Adeola; Fabiyi, James Sunday; Osuntuyi, Edward Olusola

2007-01-01

The technical properties of three layered cement-bonded boards (CBBs) made from wastepaper and sawdust were investigated. The CBBs were produced at three density levels of 1000, 1200 and 1300 kg/m 3 and at four cement/particle ratios of 2.0:1, 2.5:1, 3.0:1 and 3.5:1 on a weight to weight basis. The technical properties evaluated were modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swelling (TS). The MOR values ranged from 4.85 to 11.69 MPa and MOE values ranged from 2.80 to 5.57 GPa. The mean values of WA and TS after 24 h of water soaking of the CBBs ranged from 18.18% to 40.49% and 3.55% to 12.13%, respectively. MOR and MOE of the CBBs increased with increase in board density, but MOR decreased with the increase in cement/particle ratio. On the other hand, WA and TS decreased with increase in board density and cement/particle ratio. CBBs produced from wastepaper and sawdust at cement/particle ratios of 3.0:1 and 3.5:1 are suitable for building construction such as paneling, ceiling and partitioning

Occupational dermatitis. An epidemiological study in the rubber and cement industries

Energy Technology Data Exchange (ETDEWEB)

Varigos, G A; Dunt, D R

1981-03-01

An epidemiological study of occupational dermatitis in a tyre company and a cement company is reported. Ninety-seven percent of 999 tyre workers and 78% of 151 cement workers were screened by an occupational nurse and subsequently assessed by a specialist dermatologist. Prevalence rates of occupational contact dermatitis were 37 per 1000 and 68 per 1000 in the tyre and cement companies, respectively. Maintenance workers and tyre builders - particularly if they were Yugoslav and female - had high prevalence rates amongst tyre workers. Worker's compensation claim rates for the tyre company are similar to U.K. and U.S. rates for this industry. Prevalence rates of 37 per 1000 can be considered as a lower limit for this industry. The high prevalence rates in the cement company are noteworthy and require further study.

Alternative fuels in cement industry; Alternativa braenslen i cementindustrin

Energy Technology Data Exchange (ETDEWEB)

Nyman, K.E.; Ek, R. [Finnsementti Oy, Parainen (Finland); Maekelae, K. [Finreci Oy (Finland)

1997-10-01

In this project the cement industry`s possibilities to replace half of the fossil fuels with waste derived fuels are investigated. Bench-scale experiments, pilot plant tests and full scale tests have been done with used tires and plastics wastes

Technological, economic and financial prospects of carbon dioxide capture in the cement industry

International Nuclear Information System (INIS)

Li, Jia; Tharakan, Pradeep; Macdonald, Douglas; Liang, Xi

2013-01-01

Cement is the second largest anthropogenic emission source, contributing approximately 7% of global CO 2 emissions. Carbon dioxide capture and storage (CCS) technology is considered by the International Energy Agency (IEA) as an essential technology capable of reducing CO 2 emissions in the cement sector by 56% by 2050. The study compares CO 2 capture technologies for the cement manufacturing process and analyses the economic and financial issues in deploying CO 2 capture in the cement industry. Post-combustion capture with chemical absorption is regarded as a proven technology to capture CO 2 from the calcination process. Oxyfuel is less mature but Oxyfuel partial capture—which only recycles O 2 /CO 2 gas in the precalciner—is estimated to be more economic than post-combustion capture. Carbonate looping technologies are not yet commercial, but they have theoretical advantages in terms of energy consumption. In contrast with coal-fired power plants, CO 2 capture in the cement industry benefits from a higher concentration of CO 2 in the flue gas, but the benefit is offset by higher SO x and NO x levels and the smaller scale of emissions from each plant. Concerning the prospects for financing cement plant CO 2 capture, large cement manufacturers on average have a higher ROE (return on equity) and lower debt ratio, thus a higher discount rate should be considered for the cost analysis than in power plants. IEA estimates that the incremental cost for deploying CCS to decarbonise the global cement sector is in the range US$350–840 billion. The cost estimates for deploying state-of-the art post-combustion CO 2 capture technologies in cement plants are above $60 to avoid each tonne of CO 2 emissions. However, the expectation is that the current market can only provide a minority of financial support for CO 2 capture in cement plants. Public financial support and/or CO 2 utilisation will be essential to trigger large-scale CCS demonstration projects in the cement

The origins of American industrial success: Evidence from the US portland cement industry

OpenAIRE

Prentice, David

2008-01-01

The contributions of innovations, factor endowments and institutions to American industrialization are examined through analysing the rise of the American portland cement industry. Minerals abundance contributed in multiple ways to the spectacular rise of the industry from the 1890s. However, the results of a structural econometric analysis of entry suggests geological surveys, institutions highlighted by David and Wright, played a contributing rather than critical rol...

Potential energy savings and CO2 emissions reduction of China's cement industry

International Nuclear Information System (INIS)

Ke, Jing; Zheng, Nina; Fridley, David; Price, Lynn; Zhou, Nan

2012-01-01

This study analyzes current energy and carbon dioxide (CO 2 ) emission trends in China's cement industry as the basis for modeling different levels of cement production and rates of efficiency improvement and carbon reduction in 2011–2030. Three cement output projections are developed based on analyses of historical production and physical and macroeconomic drivers. For each of these three production projections, energy savings and CO 2 emission reduction potentials are estimated in a best practice scenario and two continuous improvement scenarios relative to a frozen scenario. The results reveal the potential for cumulative final energy savings of 27.1 to 37.5 exajoules and energy-related direct emission reductions of 3.2 to 4.4 gigatonnes in 2011–2030 under the best practice scenarios. The continuous improvement scenarios produce cumulative final energy savings of 6.0 to 18.9 exajoules and reduce CO 2 emissions by 1.0 to 2.4 gigatonnes. This analysis highlights that increasing energy efficiency is the most important policy measure for reducing the cement industry's energy and emissions intensity, given the current state of the industry and the unlikelihood of significant carbon capture and storage before 2030. In addition, policies to reduce total cement production offer the most direct way of reducing total energy consumption and CO 2 emissions. - Highlights: ► This study models output and efficiency improvements in Chinese cement industry from 2011–2030. ► Energy savings and CO 2 emission reductions estimated for 3 scenarios relative to frozen scenario. ► Results reveal cumulative final energy savings potential of 27.1–37.5 EJ and 3.2–4.4 Gt CO 2 reductions. ► Increasing efficiency is the most important policy for reducing cement energy and emissions intensity.

Application of tracer technique in cement industry

International Nuclear Information System (INIS)

Baran'ai, L.

1979-01-01

Application is stated of the radioisotope indication method in the cement industry. The method was applied in three directions. In the first direction, by means of labelling of 300 steel mill balls by cobalt-60, wear of them was examined. The degree of wear of milling balls in the process of milling was determined according to the decrease of their weight. Radioactive label served only for tracing controll balls. In the second direction, according to the natural radioactivity being presented in ashes by radioisotopes radium-226 and thorium-229, amount of ashes in the products of cement milling was determined (in the mill product, cement product, flying dust and back loading groats). In the third direction, by means of labelling of definite fractions of mille by radioisotope gold-198, optimization of technological parameters of silos were raw meal is homogenization. The following technological parameters have been established: amount of homogenized material; time of homogenization and frequency of intensity changing of supplied compressed air jet [ru

Recent developments in the cement industry: a comparative study between Mexico and India

Directory of Open Access Journals (Sweden)

Ganesh Babu Kumaran

2008-10-01

Full Text Available Since early twentieth century, the use of cement has become a popular and strategic product for economic growth of every country. In India as in Mexico, the first factories began in the earlier twentieth century, India is nowadays the world’s second largest producer and Mexico is the third firm in cement production, despite being the tenth world producer. The eighties have significate for both countries major structural changes in its economy, which have radically altered the structure and functioning of the cement industry and even more during the decade of the nineties. This article discusses the recent performance of the cement industry in both countries, compares the dynamics and causes that gave rise to these changes. It examines changes in the structure of domestic market in both countries and the strategies employed by large companies that operate in both, including a brief analysis of the role of transnational corporations in their development at the stage of globalization and liberalization of markets that characterizes the last two decades. Finally, it explores the great changes that make possible the growth and expansion of the cement industry during the period, based on technological change, the determinants of competitiveness and the role of economic policies in the development of industry in both countries.

Technical justifications for the tests and criteria in the waste form technical position appendix on cement stabilization

International Nuclear Information System (INIS)

Siskind, B.; Cowgill, M.G.

1992-01-01

As part of its technical assistance to the Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a background document for the cement stabilization appendix, Appendix A, to Rev. 1 of the Technical Position on Waste Form (TP). Here we present an overview of this background document, which provides technical justification for the stability tests to be performed on cement-stabilized waste forms and for the criteria posed in each test, especially for those tests which have been changed from their counterparts in the May 1983 Rev. 0 TP. We address guidelines for procedures from Appendix A which are considered in less detail or not at all in the Rev. 0 of the TP, namely, qualification specimen preparation (mixing, curing, storage), statistical sampling and analysis, process control program specimen preparation and examination, and surveillance specimens. For each waste form qualification test, criterion or procedural guidelines, we consider the reason for its inclusion in Appendix A, the changes from Rev. 0 of the TP (if applicable), and a discussion of the justification or rationale for these changes

Technical justifications for the tests and criteria in the waste form Technical position appendix on cement stabilization

International Nuclear Information System (INIS)

Siskind, B.; Cowgill, M.G.

1992-01-01

As part of its technical assistance to the Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a background document for the cement stabilization appendix. Appendix A, to Rev. 1 of the Technical Position on Waste Form (TP). Here we present an overview of this background document, which provides technical justification for the stability tests to be performed on cement-stabilized waste forms and for the criteria posed in each test) especially for those tests which have been changed from their counterparts in the May 1983 Rev. 0 TP. We address guidelines for procedures from Appendix A which are considered in less detail or not at all in the Rev. 0 of the TP, namely, qualification specimen preparation (mixing, curing, storage), statistical sampling and analysis, process control program specimen preparation and examination, and surveillance specimens. For each waste form qualification test, criterion or procedural guideline, we consider the reason for its inclusion in Appendix A, the changes from Rev. 0 of the TP (if applicable), and a discussion of the justification or rationale for these changes. (author)

3.7. Technical and economic aspects of the application of cement concretes obtained from local minerals

International Nuclear Information System (INIS)

Saidov, D.Kh.

2011-01-01

This article is devoted to technical and economic aspects of the application of cement concretes obtained from local minerals. The following composite materials obtained from local raw materials were considered: mineral (cement, lime), inorganic (phosphates, sodium silicate), organic (phenol formaldehyde, epoxide, urea-formaldehyde, carbamide, acryl, organosilicon, furfural aniline). It was concluded that from technical and economical points of view the most effective materials were: mineral composite materials, crude shale oils and ligno sulphonates.

Assessment of natural radioactivity levels and radiation hazards due to cement industry

International Nuclear Information System (INIS)

El-Taher, A.; Abdel Halim, A.S.

2010-01-01

The cement industry is considered as one of the basic industries that plays an important role in the national economy of developing countries. Activity concentrations of 226 Ra, 232 Th and 40 K in Assiut cement and other local cement types from different Egyptian factories has been measured by using γ-ray spectrometry. From the measured γ-ray spectra, specific activities were determined. The measured activity concentrations for these natural radionuclides were compared with the reported data for other countries. The average values obtained for 226 Ra, 232 Th and 40 K activity concentration in different types of cement are lower than the corresponding global values reported in UNSCEAR publications. The obtained results show that the averages of radiation hazard parameters for Assiut cement factory are lower than the acceptable level of 370 Bq kg -1 for radium equivalent Ra eq , 1 for level index Iγr, the external hazard index Hex ≤1 and 59 (nGy h -1 ) for absorbed dose rate. The manufacturing operation reduces the radiation hazard parameters. Cement does not pose a significant radiological hazard when used for construction of buildings.

Valorization of used tyres as fuel substitute in cement industry; Valorisation des pneus usages comme combustible de substitution en cimenterie

Energy Technology Data Exchange (ETDEWEB)

Anon.

1999-03-01

According to the French syndicate of cement industry, more than 350000 t of worn tyres are produced each year in France, among which only 143000 t are reused in retreading, exported as used tyres or valorized in cement industry. The rest is generally tipped or burnt in the open-air. In cement kilns, the organic matters of tyres are completely burnt while the metal belts supply the necessary amount of iron to the cement composition. The combustion of tyres produces no black smoke, no smell and no ash and has no significant influence on the effluents of cement factories: gases are directly filtered in the kiln by the important mass of raw materials which acts as quicklime. In 1997, 31500 t of used tyres were burnt in the seven French cement factories over 34 that use this kind of fuel and represents 1.5% of the total energy needs. This substitution ratio could easily reach 10 to 15% without leading to any additional environmental or technical problem. A project of collection and valorization of used tyres has been developed by the French ministry of environment and aims at completely eliminating tyres tipping since July 1, 2002. In order to illustrate the French policy of tyres valorization, two examples of actions are presented in this paper: the first one is carried out by the Michelin manufacturer in order to facilitate the recycling of civil engineering tyres, and the second is carried out by Ciments d`Origny company at the Rochefort factory where tyres are used as fuel substitutes. (J.S.)

Economic benefits of reducing emissions from the cement industry

International Nuclear Information System (INIS)

El-Fadel, M.; Metni, M.; Nuwayhid, M.I.; Kobrossi, R.

1999-01-01

Full text.Air pollution has recently been a growing concern in Lebanon particularly around industrial facilities and in urban areas. The cement industry constitutes a major polluting source and its impacts have historically raised considerable local public concern, as was previously the case in many developed countries. In this context, the town of Chekka, which is the site of four cement factories, has been the subject of long-lived controversy with respect to emissions and potential adverse environmental impacts. While field observations and public health complains support the presence of such impacts., scientific data are almost non-existent to adequately evaluate the actual situation. This paper describes recent efforts conducted towards a proper air quality characterization in order to shed light on the extent and nature of the impact of the cement industry in the Chekka region on its immediate vicinity. For this purpose, continuous monitoring of selected air pollutants (particulate matter, nitrogen dioxide, and carbon monoxide) was conducted during a limited period. In addition, pollutant dispersion modeling was performed to better define exposure areas. Field measurements coupled with simulation results were linked to a survey questionnaire to assess potential health and material damage on a sample area. The economic benefits of emissions reduction of selected pollutants are presented in the context of the results obtained during this study

Developing Low-Clinker Ternary Blends for Indian Cement Industry

Science.gov (United States)

Pal, Aritra

2018-05-01

In today's scenario cement-concrete has become the backbone of infrastructure development. The use of concrete is increasing day by day and so does cement. One of the major concerns is that the cement manufacturing contributes 7% of total man-made CO2 emission in the environment. At the same time India being a developing country secured the second position in cement production. On the other hand solid waste management is one of the growing problems in India. As we are one of the major contributors in this situation so, the time has come to think about the sustainable alternatives. From various researches it has been observed that the low clinker cement can be suitable option. In the present paper we have tried to develop a low clinker ternary blend for Indian cement industry using the concept of synergetic behavior of fly ash-limestone reaction and formation of more stable monocarboaluminate hydrate and hemicarboaluminate hydrate. 30% fly ash and 15% limestone and 5% gypsum have been used as supplementary cementing material for replacing 50% clinker. The mechanical properties like, compressive strength, have been studied for the fly ash limestone ternary blends cements and the results have been compared with the other controlled blends and ternary blends. The effect of intergrinding of constituent materials has shown a comparable properties which can be used for various structural application. The effect of dolomitic limestone has also been studied in fly ash limestone ternary blends and the result shows the relation between compressive strength and dolomite content is inversely proportional.

Energy consumption and CO2 emissions in China's cement industry: A perspective from LMDI decomposition analysis

International Nuclear Information System (INIS)

Xu Jinhua; Fleiter, Tobias; Eichhammer, Wolfgang; Fan Ying

2012-01-01

We analyze the change of energy consumption and CO 2 emissions in China's cement industry and its driving factors over the period 1990–2009 by applying a log-mean Divisia index (LMDI) method. It is based on the typical production process for clinker manufacturing and differentiates among four determining factors: cement output, clinker share, process structure and specific energy consumption per kiln type. The results show that the growth of cement output is the most important factor driving energy consumption up, while clinker share decline, structural shifts mainly drive energy consumption down (similar for CO 2 emissions). These efficiency improvements result from a number of policies which are transforming the entire cement industry towards international best practice including shutting down many older plants and raising the efficiency standards of cement plants. Still, the efficiency gains cannot compensate for the huge increase in cement production resulting from economic growth particularly in the infrastructure and construction sectors. Finally, scenario analysis shows that applying best available technology would result in an additional energy saving potential of 26% and a CO 2 mitigation potential of 33% compared to 2009. - Highlights: ► We analyze the energy consumption and CO 2 emissions in China's cement industry. ► The growth of cement output is the most important driving factor. ► The efficiency policies and industrial standards significantly narrowed the gap. ► Efficiency gains cannot compensate for the huge increase in cement production. ► The potentials of energy-saving of 26% and CO 2 mitigation of 33% exist based on BAT.

Critical elements in implementations of just-in-time management: empirical study of cement industry in Pakistan.

Science.gov (United States)

Qureshi, Muhammad Imran; Iftikhar, Mehwish; Bhatti, Mansoor Nazir; Shams, Tauqeer; Zaman, Khalid

2013-01-01

In recent years, inventory management is continuous challenge for all organizations not only due to heavy cost associated with inventory holding, but also it has a great deal to do with the organizations production process. Cement industry is a growing sector of Pakistan's economy which is now facing problems in capacity utilization of their plants. This study attempts to identify the key strategies for successful implementation of just-in-time (JIT) management philosophy on the cement industry of Pakistan. The study uses survey responses from four hundred operations' managers of cement industry in order to know about the advantages and benefits that cement industry have experienced by Just in time (JIT) adoption. The results show that implementing the quality, product design, inventory management, supply chain and production plans embodied through the JIT philosophy which infect enhances cement industry competitiveness in Pakistan. JIT implementation increases performance by lower level of inventory, reduced operations & inventory costs was reduced eliminates wastage from the processes and reduced unnecessary production which is a big challenge for the manufacturer who are trying to maintain the continuous flow processes. JIT implementation is a vital manufacturing strategy that reaches capacity utilization and minimizes the rate of defect in continuous flow processes. The study emphasize the need for top management commitment in order to incorporate the necessary changes that need to take place in cement industry so that JIT implementation can take place in an effective manner.

Air Pollutant Emissions Projections for the Cement and Steel Industry in China and the Impact of Emissions Control Technologies

Energy Technology Data Exchange (ETDEWEB)

Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Khanna, Nina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-03-01

China’s cement and steel industry accounts for approximately half of the world’s total cement and steel production. These two industries are two of the most energy-intensive and highest carbon dioxide (CO₂)-emitting industries and two of the key industrial contributors to air pollution in China. For example, the cement industry is the largest source of particulate matter (PM) emissions in China, accounting for 40 percent of its industrial PM emissions and 27 percent of its total national PM emissions. The Chinese steel industry contributed to approximately 20 percent of sulfur dioxide (SO_{2) emissions and 27 percent of PM emissions for all key manufacturing industries in China in 2013. In this study, we analyzed and projected the total PM and SO2 emissions from the Chinese cement and steel industry from 2010–2050 under three different scenarios: a Base Case scenario, an Advanced scenario, and an Advanced EOP (end-of-pipe) scenario. We used bottom-up emissions control technologies data and assumptions to project the emissions. In addition, we conducted an economic analysis to estimate the cost for PM emissions reductions in the Chinese cement industry using EOP control technologies, energy efficiency measures, and product change measures. The results of the emissions projection showed that there is not a substantial difference in PM emissions between the Base Case and Advanced scenarios, for both the cement and steel industries. This is mainly because PM emissions in the cement industry caused mainly by production process and not the fuel use. Since our forecast for the cement production in the Base Case and Advanced scenarios are not too different from each other, this results in only a slight difference in PM emissions forecast for these two scenarios. Also, we assumed a similar share and penetration rate of control technologies from 2010 up to 2050 for these two scenarios for the cement and steel industry. However, the Advanced EOP}

Opportunities for Energy Efficiency and Demand Response in the California Cement Industry

Energy Technology Data Exchange (ETDEWEB)

Olsen, Daniel; Goli, Sasank; Faulkner, David; McKane, Aimee

2010-12-22

This study examines the characteristics of cement plants and their ability to shed or shift load to participate in demand response (DR). Relevant factors investigated include the various equipment and processes used to make cement, the operational limitations cement plants are subject to, and the quantities and sources of energy used in the cement-making process. Opportunities for energy efficiency improvements are also reviewed. The results suggest that cement plants are good candidates for DR participation. The cement industry consumes over 400 trillion Btu of energy annually in the United States, and consumes over 150 MW of electricity in California alone. The chemical reactions required to make cement occur only in the cement kiln, and intermediate products are routinely stored between processing stages without negative effects. Cement plants also operate continuously for months at a time between shutdowns, allowing flexibility in operational scheduling. In addition, several examples of cement plants altering their electricity consumption based on utility incentives are discussed. Further study is needed to determine the practical potential for automated demand response (Auto-DR) and to investigate the magnitude and shape of achievable sheds and shifts.

Guidebook for Using the Tool BEST Cement: Benchmarking and Energy Savings Tool for the Cement Industry

Energy Technology Data Exchange (ETDEWEB)

Galitsky, Christina; Price, Lynn; Zhou, Nan; Fuqiu , Zhou; Huawen, Xiong; Xuemin, Zeng; Lan, Wang

2008-07-30

The Benchmarking and Energy Savings Tool (BEST) Cement is a process-based tool based on commercially available efficiency technologies used anywhere in the world applicable to the cement industry. This version has been designed for use in China. No actual cement facility with every single efficiency measure included in the benchmark will likely exist; however, the benchmark sets a reasonable standard by which to compare for plants striving to be the best. The energy consumption of the benchmark facility differs due to differences in processing at a given cement facility. The tool accounts for most of these variables and allows the user to adapt the model to operational variables specific for his/her cement facility. Figure 1 shows the boundaries included in a plant modeled by BEST Cement. In order to model the benchmark, i.e., the most energy efficient cement facility, so that it represents a facility similar to the user's cement facility, the user is first required to input production variables in the input sheet (see Section 6 for more information on how to input variables). These variables allow the tool to estimate a benchmark facility that is similar to the user's cement plant, giving a better picture of the potential for that particular facility, rather than benchmarking against a generic one. The input variables required include the following: (1) the amount of raw materials used in tonnes per year (limestone, gypsum, clay minerals, iron ore, blast furnace slag, fly ash, slag from other industries, natural pozzolans, limestone powder (used post-clinker stage), municipal wastes and others); the amount of raw materials that are preblended (prehomogenized and proportioned) and crushed (in tonnes per year); (2) the amount of additives that are dried and ground (in tonnes per year); (3) the production of clinker (in tonnes per year) from each kiln by kiln type; (4) the amount of raw materials, coal and clinker that is ground by mill type (in tonnes per

Quantifying the Co-benefits of Energy-Efficiency Programs: A Case Study of the Cement Industry in Shandong Province, China

Energy Technology Data Exchange (ETDEWEB)

Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lobscheid, Agnes [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dai, Yue [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-11-01

China’s cement industry accounted for more than half of the world’s total cement production in 2010. The cement industry is one of the most energy-intensive and highest carbon dioxide (CO2)-emitting industries and one of the key industrial contributors to air pollution in China. For example, it is the largest source of particulate matter (PM) emissions in China, accounting for 40 percent of industrial PM emissions and 27 percent of total national PM emissions. Although specific regulations and policies are needed to reduce the pollutant emissions from the cement industry, air pollution can also be reduced as a co-benefit of energy efficiency and climate-change mitigation policies and programs. Quantifying and accounting for these co-benefits when evaluating energy efficiency and climate-change mitigation programs reveals benefits beyond the programs’ energy and global warming impacts and adds to their cost effectiveness. In this study, we quantify the co-benefits of PM10 and sulfur dioxide (SO2) emissions reductions that result from energy-saving measures in China’s cement industry.

Reduction of Multi-pollutant Emissions from Industrial Sectors: The U.S. Cement Industry – A Case Study

Science.gov (United States)

For Frank Princiotta’s book, Global Climate Change—The Technology Challenge Carbon dioxide (CO2) accounts for more than 90% of worldwide CO2-eq green-house gas (GHG) emissions from industrial sectors other than power generation. Amongst these sectors, the cement industry is one ...

Eco-efficiency of the world cement industry: A data envelopment analysis

Energy Technology Data Exchange (ETDEWEB)

Oggioni, G., E-mail: oggioni@eco.unibs.i [University of Brescia, Faculty of Economics, Department of Quantitative Methods, IT-25122 Brescia (Italy); Riccardi, R., E-mail: riccardi@ec.unipi.i [University of Brescia, Faculty of Economics, Department of Quantitative Methods, IT-25122 Brescia (Italy); Toninelli, R., E-mail: roberta.toninelli@unifi.i [University of Pisa, Faculty of Economics, Department of Statistics and Applied Mathematics, IT-56124 Pisa (Italy)

2011-05-15

Chemical reactions and the combustion of dirty fuels, such as coal and petroleum coke (petcoke), that are used in cement production processes generate a significant amount of CO{sub 2} emissions. In this paper, we provide an eco-efficiency measure for 21 prototypes of cement industries operating in many countries by applying both a data envelopment analysis (DEA) and a directional distance function approach, which are particularly suitable for models where several production inputs and desirable and undesirable outputs are taken into account. To understand whether this eco-efficiency is due to a rational utilization of inputs or to a real carbon dioxide reduction as a consequence of environmental regulation, we analyze the cases where CO{sub 2} emissions can either be considered as an input or as an undesirable output. Empirical results show that countries where cement industries invest in technologically advanced kilns and adopt alternative fuels and raw materials in their production processes are eco-efficient. This gives a comparative advantage to emerging countries, such as India and China, which are incentivized to modernize their production processes.

Eco-efficiency of the world cement industry: A data envelopment analysis

International Nuclear Information System (INIS)

Oggioni, G.; Riccardi, R.; Toninelli, R.

2011-01-01

Chemical reactions and the combustion of dirty fuels, such as coal and petroleum coke (petcoke), that are used in cement production processes generate a significant amount of CO 2 emissions. In this paper, we provide an eco-efficiency measure for 21 prototypes of cement industries operating in many countries by applying both a data envelopment analysis (DEA) and a directional distance function approach, which are particularly suitable for models where several production inputs and desirable and undesirable outputs are taken into account. To understand whether this eco-efficiency is due to a rational utilization of inputs or to a real carbon dioxide reduction as a consequence of environmental regulation, we analyze the cases where CO 2 emissions can either be considered as an input or as an undesirable output. Empirical results show that countries where cement industries invest in technologically advanced kilns and adopt alternative fuels and raw materials in their production processes are eco-efficient. This gives a comparative advantage to emerging countries, such as India and China, which are incentivized to modernize their production processes.

Use of secondary fuels in rotary kilns of the cement industry; Einsatz von Sekundaerstoffen in Drehofenanlagen der Zementindustrie

Energy Technology Data Exchange (ETDEWEB)

Hoenig, V. [Forschungsinstitut der Zementindustrie, Duesseldorf (Germany)

1998-09-01

Most cement works in Germany use secondary materials for cement production or are planning to do so. Many of the materials in question, such as used tyres, have been recycled in an environmentally acceptable way for decades, and a large body of experience has accumulated on their use in the cement industry. In the cement industry secondary materials are understood to comprise secondary fuels as well as secondary raw materials. The latter have for some part replaced the natural raw materials used for burning cement clinker, the preliminary product of cement. By using used tyres, used oil and other waste materials as secondary fuels the cement industry has for decades contributed to an environmentally acceptable form of waste disposal. The use of secondary materials has also enabled the cement industry to improve its economic situation. In response to the enactment of the Materials Recycling Law the cement industry has during the past few years turned its attention to the utilisation of other waste materials. The criteria relevant to the cement industry`s choice of a waste material as secondary material lastly depends on the process-related side constraints attending the clinker burning process and the requirements on the burning process with regard to product quality and environmental acceptability. [Deutsch] Die meisten Zementwerke in Deutschland setzen bei der Zementherstellung Sekundaerstoffe ein oder planen ihren Einsatz. Fuer einige dieser Stoffe, wie z.B. Altreifen gilt, dass sie bereits seit Jahrzehnten umweltvertraeglich verwertet werden, so dass viele Erfahrungen ueber deren Einsatz in der Zementindustrie vorliegen. Unter Sekundaerstoffen werden in der Zementindustrie sowohl Sekundaerbrennstoffe wie auch Sekundaerrohstoffe verstanden. Letztere ersetzen teilweise die natuerlichen Rohstoffe, aus denen der Zementklinker, das Vorprodukt des Zements, gebrannt wird. Bezueglich der Sekundaerbrennstoffe traegt die Zementindustrie schon seit Jahrzehnten zu einer

Can Imports Discipline Collusive Firms? Case of the Philippine Cement Industry

OpenAIRE

Rafaelita M. Aldaba

2008-01-01

Applying a conjectural variations (CV) model introduced by Haskel and Scaramozzino (H&S model 1997), the paper examines the impact of trade liberalization on the Philippine cement industry where alleged cartel activities have taken place after the entry of the worlds Big Three cement firms : Holcim, Cemex, and Lafarge. In the H&S model, the relationship between firm behavior and competition is estimated with price cost margin (price minus marginal costs over price) as indicator of competition...

Advanced dust control techniques in cement industry electrostatic precipitator - a case study

International Nuclear Information System (INIS)

Khattak, Z.; Ahmad, J.

2011-01-01

The case study deal with the current day problem of pollution by industrial zones in Pakistan with emphasis on the cement Industry which has been proved to be the second revenue generating hub after textile sector of the Pakistan. A pilot study into the identification and available removal Techniques of particulates from the exhaust of a cement plant clinker cooler was carried out. The objective of this work was to study the performance of the each technique in detail in the removal of a particulate with a wide range of sizes, under different operational conditions and to compare the results for collection efficiency with predictions by available theoretical models. A brief and comprehensive discussion regarding design, construction and bottlenecks of each tool has been discussed to fully ascertain it's scope and usability. First part of the study identifies the various pollutants being emitted from the chimney of a specific cement plant in Pakistan and while last portion deals with the ways to curtail these pollutants. (author)

Dust exposure and the risk of cancer in cement industry workers in Korea.

Science.gov (United States)

Koh, Dong-Hee; Kim, Tae-Woo; Jang, Seunghee; Ryu, Hyang-Woo

2013-03-01

Cement is used widely in the construction industry, though it contains hazardous chemicals such as hexavalent chromium. Several epidemiological studies have examined the association between cement dust exposure and cancer, but these associations have proved inconclusive. In the present study, we examined the association between dust exposure and cancer in cement industry workers in Korea. Our cohort consisted of 1,324 men who worked at two Portland cement manufacturing factories between 1997 and 2005. We calculated cumulative dust exposures, then categorized workers into high and low dust exposure groups. Cancer cases were identified between 1997 and 2005 by linking with the national cancer registry. Standardized incidence ratios (SIRs) were calculated for all workers and the high and low dust exposure groups, respectively. The SIR for overall cancers in all workers was increased (1.35, 95% CI: 1.01-1.78). The SIR for stomach cancer in the high dust exposure group was increased (2.18, 95% CI: 1.19-3.65), but there was no increased stomach cancer risk in the low dust exposure group. The SIR for rectal cancer in all workers was increased (3.05, 95% CI: 1.32-6.02). Rectal cancer risk was similar in the high and low exposure groups. Our findings suggest a potential association between exposure in the cement industry and an increased risk of stomach and rectal cancers. However, due to the small number of cases, this association should be further investigated in a study with a longer follow-up period and adjustment for confounders. Copyright © 2012 Wiley Periodicals, Inc.

Solidification process for toxic and hazardous wastes. Second part: Cement solidification matrices

International Nuclear Information System (INIS)

Donato, A.; Arcuri, L.; Dotti, M.; Pace, A.; Pietrelli, L.; Ricci, G.; Basta, M.; Cali, V.; Pagliai, V.

1989-05-01

This paper reports the second part of a general study carried out at the Nuclear Fuel Division aiming at verifying the possible application of the radioactive waste solidification processes to industrial hazardous wastes (RTN). The cement solidification of several RTN types has been taken into consideration, both from the technical and from the economic point of view. After a short examination of the Italian juridical and economical situation in the field, which demonstrates the need of the RTN solidification, the origin and characteristics of the RTN considered in the study and directly provided by the producing industries are reviewed. The laboratory experimental results of the cementation of RTN produced by gold manufacturing industries and by galvanic industries are reported. The cementation process can be considered a very effective mean for reducing both the RTN management costs and the environmental impact of RTN disposal. (author)

Microwave processing of cement and concrete materials – towards an industrial reality?

International Nuclear Information System (INIS)

Buttress, Adam; Jones, Aled; Kingman, Sam

2015-01-01

Each year a substantial body of literature is published on the use of microwave to process cement and concrete materials. Yet to date, very few if any have lead the realisation of a commercial scale industrial system and is the context under which this review has been undertaken. The state-of the–art is evaluated for opportunities, and the key barriers to the development of new microwave-based processing techniques to enhance production, processing and recycling of cement and concrete materials. Applications reviewed include pyro-processing of cement clinker; accelerated curing, non-destructive testing and evaluation (NDT&E), and end-of-life processing including radionuclide decontamination

Utilization coke dust as fuel in the cement industry

International Nuclear Information System (INIS)

Nawaz, S.

2006-01-01

Utilization of coke dust available from coal carbonization plants, as a fuel in the cement industry has been undertaken and discussed in this research paper. The parameters studied include physical and chemical evaluation of the coke dust and its economic feasibility/ suitability as fuel for the cement plants. Detailed studies have been carried out on the above referred parameters. In addition a comparative study has been done to access its suitability in comparison to other fuels especially imported coal. It has been found that the coke dust contained about 66% fixed carbon, 29% ash, 4% volatile matter, 1% moisture and 0.48% sulphur. It gross calorific value was found to be 5292 Kcal/kg. The detailed analysis of coke dust ash was also performed to determine as to how its constituents will compare with the cement constituents. Keeping in view the experimental results/ data generated on the coke dust, it has been concluded that it can be quite a good substitute for imported coal. In doing so a substantial financial saving can be achieved which ranges 40-45%. (author)

Quantifying the co-benefits of energy-efficiency policies: a case study of the cement industry in Shandong Province, China.

Science.gov (United States)

Hasanbeigi, Ali; Lobscheid, Agnes; Lu, Hongyou; Price, Lynn; Dai, Yue

2013-08-01

In 2010, China's cement industry accounted for more than half of the world's total cement production. The cement industry is one of the most energy-intensive and highest carbon dioxide (CO2)-emitting industries, and thus a key industrial contributor to air pollution in China. For example, it is the largest source of particulate matter (PM) emissions in China, accounting for 40% of industrial PM emissions and 27% of total national PM emissions. In this study, we quantify the co-benefits of PM10 and sulfur dioxide (SO2) emission reductions that result from energy-saving measures in the cement industry in Shandong Province, China. We use a modified form of the cost of conserved energy (CCE) equation to incorporate the value of these co-benefits. The results show that more than 40% of the PM and SO2 emission reduction potential of the electricity-saving measures is cost effective even without taking into account the co-benefits for the electricity-saving measures. The results also show that including health benefits from PM10 and/or SO2 emission reductions reduces the CCE of the fuel-saving measures. Two measures that entail changing products (production of blended cement and limestone Portland cement) result in the largest reduction in CCE when co-benefits were included, since these measures can reduce both PM10 and SO2 emissions, whereas the other fuel-saving measures do not reduce PM10. Published by Elsevier B.V.

Industrial Wastes as Auxiliary Additives to Cement/Lime Stabilization of Soils

Directory of Open Access Journals (Sweden)

Jijo James

2016-01-01

Full Text Available Chemical stabilization involves the use of chemical agents for initiating reactions within the soil for modification of its geotechnical properties. Cement and lime stabilization have been the most common stabilization methods adopted for soil treatment. Cement stabilization results in good compressive strengths and is preferred for cohesionless to moderately cohesive soil but loses effectiveness when the soil is highly plastic. Lime stabilization is the most preferred method for plastic clays; however, it proves to be ineffective in sulphate rich clays and performs poorly under extreme conditions. With such drawbacks, lots of researches have been undertaken to address the issues faced with each stabilization method, in particular, the use of solid wastes for soil stabilization. Solid waste reuse has gained high momentum for achieving sustainable waste management in recent times. Research has shown that the use of solid wastes as additives with and replacement for conventional stabilizers has resulted in better results than the performance of either individually. This review provides insight into some of the works done by earlier researchers on lime/cement stabilization with industrial wastes as additives and helps to form a sound platform for further research on industrial wastes as additives to conventional stabilizers.

the Danish cement industry

OpenAIRE

la Cour, Lisbeth Funding; Møllgård, Peter

2001-01-01

We test econometrically whether the sole Danish producer of cement holds a dominant position in the Danish market for (grey) cement. In import penetration tests, we find that its pricing and quantity decisions are independent of import price and quantity, implying that it can act to a considerable extent independently of its competitors. We also test whether it can act independently of its customers and find that its demand is inelastic with respect to its price. It thus holds a dominant posi...

Mapping and modeling multiple benefits of energy efficiency and emission mitigation in China’s cement industry at the provincial level

International Nuclear Information System (INIS)

Zhang, Shaohui; Worrell, Ernst; Crijns-Graus, Wina

2015-01-01

Highlights: • Provincial disparities in energy use and emissions are quantified for China’s cement industry. • We describe emission mitigation impacts on EEMs with integrated assessment model. • We quantify the multiple benefits potential in China’s cement industry on provincial level. • Energy efficiency would lead to huge reductions in air pollution in all provinces. • We discuss uncertainty in relation to distribution of energy saving and emission reduction. - Abstract: China’s cement industry is the second largest energy consumer and key emitter of CO 2 and air pollutants. It accounts for 7% of total energy consumption in China and 15% of CO 2 , 21% of PM, 4% SO 2 and 10% of NOx of total emissions, respectively. Provincial disparities in energy consumption and emissions of CO 2 and air pollutants in China’s cement industry are rarely quantified. In this study, an integrated assessment model including provincial energy conservation supply curves (ECSC) (which can shows the cost-effective and technical energy saving potential per province), the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model (which can be used to calculate air pollutant emissions), and ArcGIS (a geographical information system (GIS) with elaborated spatial functions) is developed and used to assess the potential of energy savings in terms of emission mitigation of CO 2 and air pollutants and multiple benefits of energy efficiency measures at the provincial level during the period 2011–2030. The results show significant heterogeneity across provinces in terms of potential of energy saving as well as emission mitigation of CO 2 and air pollutants (i.e. PM, SO 2 , and NOx) in the next two decades. Seven provinces (i.e. Shandong, Sichuan, Jiangsu, Guangdong, Zhejiang, Henan, Hebei), six of which are located in the central- and east-China, account for 47% of the total energy saving potential, equivalent to 26% of baseline energy use in 2030. The energy

Assessment of the thermal performance and energy conservation opportunities of a cement industry in Indonesia

International Nuclear Information System (INIS)

Rasul, M.G.; Widianto, W.; Mohanty, B.

2005-01-01

A simple model is presented to assess the thermal performance of a cement industry with an integrated view to improve the productivity of the plant. The model is developed on the basis of mass, energy and exergy balance and is applied to an existing Portland cement industry in Indonesia. The data obtained from industry show that the burning efficiency and the second law efficiency of the kiln system are 52.07% and 57.07% respectively. Cooler efficiency and heat recovery efficiency are 47.75% and 51.2% respectively. The unaccounted loss at kiln system was found to be 1.85% and that of cooler system was 19%. The high loss at cooler was mainly due to the convection and radiation losses from the uninsulated cooler. Irreversibility of the system was found to be about 20%, which is due to the conversion from chemical to thermal energy. The thermal energy conservation opportunities are identified. This study show that by replacing industrial diesel oil (IDO) with waste heat recovery from kiln and cooler exhaust for drying of raw meal and fuel, and preheating of combustion air, a cement industry in Indonesia can save about 1.264 x 10 5 US dollars per year

Final Rule: NESHAP for the Portland Cement Manufacturing Industry: Alternative Monitoring Method

Science.gov (United States)

EPA is extending its approval for the use of an alternative method to show compliance with hydrogen chloride (HCl) emissions limits in the National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry

AIR POLLUTION AND LUNG CAPACITY OF PEOPLE LIVING AROUND THE CEMENT INDUSTRY, INDONESIA

Directory of Open Access Journals (Sweden)

Erwin Azizi Jayadipraja

2016-05-01

Full Text Available Backgrounds: A cement industry is one of anthropogenic sources of air pollution. In polluting the air, the industry creates some dust particles, nitrogen oxide (NO2, sulfur oxide (SO2, and carbon monoxide (CO. Research Purpose: The research aimed at finding out the ambient air quality around a cement industry and relating it with the lung capacity of people living around the area. Methodology: This was a cross sectional studies by measuring the ambient air quality in the morning, noon, and evening in four different settlements within 3 km from the cement industry. The measurement is then correlated with the FEV1 and FVC of lung capacity of people living around the area. Result: Of all four locations, three have ambient air quality (PM2.5 = 109.47 µg/Nm3, TSP = 454.7 µg/Nm3 that surpass the quality standard (PM2.5 = 65 µg/Nm3, TSP = 230 µg/Nm3. Of 241 respondents, the average level of FVC and FEV1 is respectively 1.9352 liter (SD: 0.45578 and 1.7486 liter (SD: 0.43874. Furthermore, the level of PM2.5 in the morning and at noon is respectively p=0.009 and p=0.003; the level of TSP in the morning and at noon is respectively p=0.003 and p=0.01; the level of NO2 in the morning is p=0.006; the level of SO2 in the morning, at noon and in the evening is respectively p=0.000, p=0.022, and p=0.000; and the level of CO in the morning, at noon and in the evening is respectively p=0.003, p=0.015, and p=0.024. Those levels are associated with the level of respondents’ FEV1. Moreover, the level of TSP in the morning is p=0.024; the level of SO2 in the morning and in the evening is p=0.007. These levels relate to the level of respondents’ FVC. Conclusion: The ambient air quality around a cement industry is affected by dispersion of industrial emission and of other sources which can cause some impairment to lung capacity.

A new on-belt elemental analyzer for the cement industry

International Nuclear Information System (INIS)

Sowerby, B.D.; Lim, C.S.; Tickner, J.R.; Manias, C.; Retallack, D.

2001-01-01

On-line control of raw mill feed composition is a key to the improved control of cement plants. Elements of primary importance to the industry are calcium, silicon, aluminum and iron. Direct on-conveyor belt analysis of raw mill feed is required, independent of changes in belt loading, moisture content, and both horizontal and vertical segregation. A new and improved on-conveyor belt elemental analyzer for cement raw mill feed has been developed and tested successfully in Adelaide Brighton's Birkenhead cement plant. The analyzer utilizes two 241 Am-Be neutron sources and multiple BGO detectors to measure both neutron inelastic scatter and thermal neutron capture gamma rays. Dynamic tests in the plant on highly segregated material having depths in the range 100 to 200 mm have shown analyzer total RMS errors of 0.49, 0.52, 0.38 and 0.23 wt.% (on a loss free basis) for CaO, SiO 2 , Al 2 O 3 , and Fe 2 O 3 respectively, when 10-minute counting periods are used

Cement-latex grouting mortar for cementing boreholes

Energy Technology Data Exchange (ETDEWEB)

Kateev, I S; Golyshkina, L A; Gorbunova, I V; Kurochkin, B M; Vakula, Ya V

1980-01-01

The need for the development of cement-latex grouting mortar for the purpose of separating strata when reinforcing boreholes at deposits in the Tatar Associated SSR is evaluated. Results of studies of the physical and mechanical properties of cement-latex grouting mortar systems (mortar plus brick) are presented. Formulas for preparing cement-latex grouting mortor are evaluated and results of industrial tests of such mortars shown.

Physical, chemical and radioactive characterization of co-products from titanium dioxide industry for valorization in the cement industry

International Nuclear Information System (INIS)

Gazquez, M.J.; Mantero, J.; Bolivar, J.P.; Garcia-Tenorio, R.; Vaca, F.

2011-01-01

The present study was conducted to characterize the raw materials (ilmenite and slag), waste (red gypsum) and several co-products (sulphate monohydrate and sulphate heptahydrated) form the titanium dioxide industry in relation to their elemental composition (major, minor and trace elements), granulometry, mineralogy, microscopic morphology, physical composition and radioactive content in order to apply this knowledge in the valorization of the co-products in the fields such a as construction, civil engineering, etc. In particular, the main properties of cements produced with different proportions of red gypsum were studied, and the obtained improvements, in relation to Ordinary Portland Cements (OPC) were evaluated. It was also demonstrated that the levels of pollutants and the radioactive content in the produced RG cements, remain within the regulated safety limits. (Author). 38 refs.

[Silicosis and industrial bronchitis by exposure to silica powders and cement].

Science.gov (United States)

Méndez-Vargas, María Martha; Báez-Revueltas, Fabiola Berenice; López-Rojas, Pablo; Tovalín-Ahumada, José Horacio; Zamudio-Lara, José Othón; Marín-Cotoñieto, Irma Araceli; Villeda, Francisco

2013-01-01

to identify the association between the exposure of workers to inorganic dust in a quarry and a cement factory and pulmonary diseases. a transverse study on data from 32 quarry workers (QWs) and 57 cement production line workers (CFWs) to inorganic-dust exposure was performed. Pulmonary function tests and chest X ray were done in both groups. there were differences between QWs and the CFWs; QWs were younger, shorter and thinner. The number of sick individuals might be considered significantly different, showing a smaller proportion on the cement production line. The quarry workers have been on the company for a shorter period of time and, in the end, they present more serious pulmonary problems with an average of 3 years working. the amount of free-silica that is managed on the quarry affects the workers in some way, even when literature states that the evolution of industrial bronchitis and silicosis have a period development of approximately 10 years.

Development of Bulk Nanocrystalline Cemented Tungsten Carbide for Industrial Applicaitons

Energy Technology Data Exchange (ETDEWEB)

Z. Zak Fang, H. Y. Sohn

2009-03-10

This report contains detailed information of the research program entitled "Development of Bulk Nanocrystalline Cemented Tungsten Carbide Materials for Industrial Applications". The report include the processes that were developed for producing nanosized WC/Co composite powders, and an ultrahigh pressure rapid hot consolidation process for sintering of nanosized powders. The mechanical properties of consolidated materials using the nanosized powders are also reported.

Technology Roadmaps: Cement

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

To support its roadmap work focusing on key technologies for emissions reductions, the International Energy Agency (IEA) also investigated one particular industry: cement. Cement production includes technologies that are both specific to this industry and those that are shared with other industries (e.g., grinding, fuel preparation, combustion, crushing, transport). An industry specific roadmap provides an effective mechanism to bring together several technology options. It outlines the potential for technological advancement for emissions reductions in one industry, as well as potential cross-industry collaboration.

Technical writing practically unified through industry

Science.gov (United States)

Houston, L. S.

1981-01-01

General background details in the development of a university level technical writing program, based upon the writing tasks of the student's occupations, are summarized. Objectives and methods for unifying the courses of study with the needs of industry are discussed. Four academic course divisions, Industries Technologies, in which preparation and training are offered are: Animal, Horticulture, Agriculture, and Agricultural Business. Occupational competence is cited as the main goal for these programs in which technical writing is to be practically unified through industry. Course descriptions are also provided.

NESHAP for the Portland Cement Manufacturing Industry: Fact Sheets for Actions Since 2015

Science.gov (United States)

EPA is extending its approval for the use of an alternative method to show compliance with hydrogen chloride (HCl) emissions limits in the National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry

Potential use of pyrite cinders as raw material in cement production: results of industrial scale trial operations.

Science.gov (United States)

Alp, I; Deveci, H; Yazici, E Y; Türk, T; Süngün, Y H

2009-07-15

Pyrite cinders, which are the waste products of sulphuric acid manufacturing plants, contain hazardous heavy metals with potential environmental risks for disposal. In this study, the potential use of pyrite cinders (PyCs) as iron source in the production of Portland cement clinker was demonstrated at the industrial scale. The chemical and mineralogical analyses of the PyC sample used in this study have revealed that it is essentially a suitable raw material for use as iron source since it contains >87% Fe(2)O(3) mainly in the form of hematite (Fe(2)O(3)) and magnetite (Fe(3)O(4)). The samples of the clinkers produced from PyC in the industrial scale trial operation of 6 months were tested for the conformity of their chemical composition and the physico-mechanical performance of the resultant cement products. The data were compared with the clinker products of the iron ore, which is used as the raw material for the production Portland cement clinker in the plant. The chemical compositions of all the clinker products of PyC appeared to conform to those of the iron ore clinker, and hence, a Portland cement clinker. The mechanical performance of the mortars prepared from the PyC clinker was found to be consistent with those of the industrial cements e.g. CEM I type cements. It can be inferred from the leachability tests (TCLP and SPLP) that PyC could be a potential source of heavy metal pollution while the mortar samples obtained from the PyC clinkers present no environmental problems. These findings suggest that the waste pyrite cinders can be readily used as iron source for the production of Portland cement. The availability of PyC in large quantities at low cost provides further significant benefits for the management/environmental practices of these wastes and for the reduction of mining and processing costs of cement raw materials.

Feasibility of using ceramic furnace wastes in cement composites

International Nuclear Information System (INIS)

Fazzan, J.V.; Sanches, A.O.; Akasaki, J.L.; Malmonge, J.A.

2016-01-01

Currently, the region of Epitacio-SP President is classified as Paulista West Center in the production of ceramic tiles and bricks. However, as these industries have also generated environmental impacts in the production process with the generation of waste, the construction industries presents as great potential to absorb a large portion of these materials, called Pozzolans. In this sense, the research aims to study the characterization of Ceramic Furnace Wastes (CFC) and the evaluation of their reactivity. Mortar specimens were molded with different waste percentages in partial replacement of Portland cement, for analysis of compressive strength and capillary water absorption test. The characterization results show that important properties can be obtained by the preparation conditions of ashes, besides obtaining resistant activity index higher than expected by technical standards when using the material in replacement of Portland cement. (author)

Barium aluminate cement: its application

International Nuclear Information System (INIS)

Drozdz, M.; Wolek, W.

1975-01-01

The technology of manufacturing barium aluminate cement from barium sulfate and alumina, using a rotary kiln for firing the clinker is described. The method of granulation of the homogenized charge was used. Conditions of using the ''to mud'' method in industry were indicated. The physical and chemical properties of barium aluminate cement are determined and the quality of several batches of cement prepared on a semi-industrial scale and their suitability for making highly refractory concretes are tested. The optimal composition of the concretes is determined as a function of the mixing water and barium aluminate cement contents. Several experimental batches of concretes were used in the linings of furnaces in the steel industry. The suitability of these cements for use in fields other than steelmaking is examined. It is established that calcium aluminate cement has certain limited applications [fr

International comparisons of energy efficiency in power, steel, and cement industries

International Nuclear Information System (INIS)

Oda, Junichiro; Akimoto, Keigo; Tomoda, Toshimasa; Nagashima, Miyuki; Wada, Kenichi; Sano, Fuminori

2012-01-01

Industrial energy efficiency is of paramount importance both for conserving energy resources and reducing CO 2 emissions. In this paper, we compare specific energy consumption among countries in fossil power generation, steel, and cement sectors. The evaluations were conducted using common system boundaries, allocation, and calculation methods. In addition, we disaggregate within sectors, such as with blast furnace–basic oxygen furnace (BF–BOF) steel and scrap-based electric arc furnace (Scrap-EAF) steel. The results reveal that characteristics vary by sub-sector. Regional differences in specific energy consumption are relatively large in the power, BF–BOF steel, and cement sectors. For coal power generation and BF–BOF steel production, continual maintenance and rehabilitation are of key importance. We confirm these key factors identified in the previous work on our estimated numerical values. In BF–BOF steel production, corrections for hot metal ratios (pig iron production per unit of BOF crude steel production) and quality of raw materials have a large effect on the apparent specific energy consumption. Available data is not yet sufficient for straightforward evaluation of the steel and cement sectors. - Highlights: ► We compare energy efficiency among countries in power, steel, and cement sectors. ► In steel and cement sectors, the results are provided in terms of specific energy consumption (GJ/ton of product). ► We distinguish BOF steel and EAF steel. ► New installation and continual maintenance are the key for energy efficiency. ► Corrections have a large impact on apparent specific energy consumption.

Natural radioactivity and human exposure by raw materials and end product from cement industry used as building materials

International Nuclear Information System (INIS)

Stojanovska, Z.; Nedelkovski, D.; Ristova, M.

2010-01-01

During the manufacturing process in the cement industry, raw materials of different levels of natural radioactivity are utilized. In this study we present the radiological impact of cements as a building material and the different raw materials used in their manufacture. A total of 218 samples of raw materials and their end product cements were collected from the cement industry of Macedonia (The Former Yugoslav Republic) during the period 2005-2007. The specific activities, evaluated by gamma spectrometry analysis, showed the highest mean specific activity in fly ash ( 226 Ra, 107 ± 45 Bq kg -1 ; 232 Th, 109 ± 30 Bq kg -1 ; 40 K, 685 ± 171 Bq kg -1 ), which is used as a raw material. However, the final cement product usually has relatively lower activity compared with the activity of the raw material and the mean specific activity of the final cement products were lower ( 226 Ra, 42 ± 10 Bq kg -1 ; 232 Th, 28 ± 6 Bq kg -1 ; 40 K, 264 ± 50 Bq kg -1 ). The radium equivalent activity and the hazard index were calculated for each sample to assess the radiation hazard. The mean annual effective dose originating from the cements was found to be 111 ± 22 μSv y -1 , which is below the recommended EC limit of 300 μSv y -1 .

Biomonitoring spatial and temporal impact of atmospheric dust from a cement industry

International Nuclear Information System (INIS)

Branquinho, Cristina; Gaio-Oliveira, Gisela; Augusto, Sofia; Pinho, Pedro; Maguas, Cristina; Correia, Otilia

2008-01-01

The objective of this work was to evaluate the spatial and temporal impact of dust-pollution in the vicinity of a cement industry, located in an area with dry climate. The spatial impact integrated over time was evaluated from the concentrations of Ca, Fe and Mg in in-situ Xanthoria parietina. The temporal pattern was assessed through one-month transplants of the lichen Ramalina canariensis. Four potential sources of atmospheric dust were evaluated: the limestone-quarry; the unpaved roads, the deposit area and the cement mill. Calcium concentration in lichens was considered the best cement-dust indicator. Different types of dust (clinker and grinded-limestone-dust) resulted in different time-patterns of Ca accumulation, which was also related with the different influence that wet and dry periods have in the lichen accumulation process. The dust pollution was found to be deposited locally and dependent on: the nature of dust particles and the volume and frequency of precipitation. - Biomonitoring Spatial and Temporal dust emissions in dry climates

Biomonitoring spatial and temporal impact of atmospheric dust from a cement industry

Energy Technology Data Exchange (ETDEWEB)

Branquinho, Cristina [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Campo Grande, Edificio C2, Piso 4, 1749-016 Lisbon (Portugal); Universidade Atlantica, Antiga Fabrica da Polvora de Barcarena, 2745-615 Barcarena (Portugal)], E-mail: cmbranquinho@fc.ul.pt; Gaio-Oliveira, Gisela; Augusto, Sofia; Pinho, Pedro; Maguas, Cristina; Correia, Otilia [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Campo Grande, Edificio C2, Piso 4, 1749-016 Lisbon (Portugal)

2008-01-15

The objective of this work was to evaluate the spatial and temporal impact of dust-pollution in the vicinity of a cement industry, located in an area with dry climate. The spatial impact integrated over time was evaluated from the concentrations of Ca, Fe and Mg in in-situ Xanthoria parietina. The temporal pattern was assessed through one-month transplants of the lichen Ramalina canariensis. Four potential sources of atmospheric dust were evaluated: the limestone-quarry; the unpaved roads, the deposit area and the cement mill. Calcium concentration in lichens was considered the best cement-dust indicator. Different types of dust (clinker and grinded-limestone-dust) resulted in different time-patterns of Ca accumulation, which was also related with the different influence that wet and dry periods have in the lichen accumulation process. The dust pollution was found to be deposited locally and dependent on: the nature of dust particles and the volume and frequency of precipitation. - Biomonitoring Spatial and Temporal dust emissions in dry climates.

Evaluating co-benefits of energy efficiency and air pollution abatement in China’s cement industry

NARCIS (Netherlands)

Zhang, Shaohui; Worrell, Ernst; Crijns - Graus, Wina

2015-01-01

China’s cement industry is the world’s largest and is one of the largest energy consuming, and GHG and air pollutant emitting industries. Actions to improve energy efficiency by best available technology can often bring co-benefits for climate change and air quality through reducing emissions of

CT-guided vertebroplasty: analysis of technical results, extraosseous cement leakages, and complications in 500 procedures

International Nuclear Information System (INIS)

Pitton, Michael Bernhard; Herber, Sascha; Koch, Ulrike; Oberholzer, Katja; Dueber, Christoph; Drees, Philip

2008-01-01

The aim of this study was to analyze the technical results, the extraosseous cement leakages, and the complications in our first 500 vertebroplasty procedures. Patients with osteoporotic vertebral compression fractures or osteolytic lesions caused by malignant tumors were treated with CT-guided vertebroplasty. The technical results were documented with CT, and the extraosseous cement leakages and periinterventional clinical complications were analyzed as well as secondary fractures during follow-up. Since 2002, 500 vertebroplasty procedures have been performed on 251 patients (82 male, 169 female, age 71.5 ± 9.8 years) suffering from osteoporotic compression fractures (n = 217) and/or malignant tumour infiltration (n = 34). The number of vertebrae treated per patient was 1.96 ± 1.29 (range 1-10); the numbers of interventions per patient and interventions per vertebra were 1.33 ± 0.75 (range 1-6) and 1.01 ± 0.10, respectively. The amount of PMMA cement was 4.5 ± 1.9 ml and decreased during the 5-year period of investigation. The procedure-related 30-day mortality was 0.4% (1 of 251 patients) due to pulmonary embolism in this case. The procedure-related morbidity was 2.8% (7/251), including one acute coronary syndrome beginning 12 h after the procedure and one missing patellar reflex in a patients with a cement leak near the neuroformen because of osteolytic destruction of the respective pedicle. Additionally, one patient developed a medullary conus syndrome after a fall during the night after vertebroplasty, two patients reached an inadequate depth of conscious sedation, and two cases had additional fractures (one pedicle fracture, one rib fracture). The overall CT-based cement leak rate was 55.4% and included leakages predominantly into intervertebral disc spaces (25.2%), epidural vein plexus (16.0%), through the posterior wall (2.6%), into the neuroforamen (1.6%), into paravertebral vessels (7.2%), and combinations of these and others. During follow-up (15

CT-guided vertebroplasty: analysis of technical results, extraosseous cement leakages, and complications in 500 procedures

Energy Technology Data Exchange (ETDEWEB)

Pitton, Michael Bernhard; Herber, Sascha; Koch, Ulrike; Oberholzer, Katja; Dueber, Christoph [Johannes Gutenberg-University of Mainz, Department of Diagnostic and Interventional Radiology, Mainz (Germany); Drees, Philip [University Hospital, Johannes Gutenberg-University of Mainz, Department of Orthopedic Surgery, Mainz (Germany)

2008-11-15

The aim of this study was to analyze the technical results, the extraosseous cement leakages, and the complications in our first 500 vertebroplasty procedures. Patients with osteoporotic vertebral compression fractures or osteolytic lesions caused by malignant tumors were treated with CT-guided vertebroplasty. The technical results were documented with CT, and the extraosseous cement leakages and periinterventional clinical complications were analyzed as well as secondary fractures during follow-up. Since 2002, 500 vertebroplasty procedures have been performed on 251 patients (82 male, 169 female, age 71.5 {+-} 9.8 years) suffering from osteoporotic compression fractures (n = 217) and/or malignant tumour infiltration (n = 34). The number of vertebrae treated per patient was 1.96 {+-} 1.29 (range 1-10); the numbers of interventions per patient and interventions per vertebra were 1.33 {+-} 0.75 (range 1-6) and 1.01 {+-} 0.10, respectively. The amount of PMMA cement was 4.5 {+-} 1.9 ml and decreased during the 5-year period of investigation. The procedure-related 30-day mortality was 0.4% (1 of 251 patients) due to pulmonary embolism in this case. The procedure-related morbidity was 2.8% (7/251), including one acute coronary syndrome beginning 12 h after the procedure and one missing patellar reflex in a patients with a cement leak near the neuroformen because of osteolytic destruction of the respective pedicle. Additionally, one patient developed a medullary conus syndrome after a fall during the night after vertebroplasty, two patients reached an inadequate depth of conscious sedation, and two cases had additional fractures (one pedicle fracture, one rib fracture). The overall CT-based cement leak rate was 55.4% and included leakages predominantly into intervertebral disc spaces (25.2%), epidural vein plexus (16.0%), through the posterior wall (2.6%), into the neuroforamen (1.6%), into paravertebral vessels (7.2%), and combinations of these and others. During follow

Environmental health survey in asbestos cement sheets manufacturing industry.

Science.gov (United States)

Ansari, F A; Bihari, V; Rastogi, S K; Ashquin, M; Ahmad, I

2007-01-01

About 673 small-scale asbestos mining and milling facilities and 33 large - scale asbestos manufacturing plants, (17 asbestos-cement product manufacturing plants and 16 other than asbestos-cement product plants) are situated in India. The present study reveals the exposure of commercial asbestos (chrysotile) in the occupational as well as ambient air environment of the asbestos-cement (AC) sheets industry using membrane filter method of Bureau of Indian Standards (BIS). The fibre concentrations in 15 samples collected in the occupational environment at ingredient feeding site, sheet-producing site, fibre godown were 0.079, 0.057 and 0.078 f/cc, respectively and in five samples from surrounding ambient air at factory gate resulted fibre concentration of 0.071 f/cc. All the samples have shown fibre concentration lower than the threshold limit values (TLVs) prescribed by BIS. Morphological analysis of samples, further under phase contrast and polarized microscopy indicates the presence of chrysotile asbestos, which acts as carcinogen as well as co-carcinogen. A clinical examination of exposed subjects reveals that there was no case of clubbing, crepitation, ronchi and dyspnea on exertion; however, obstruction and restriction were 10.9 per cent and 25 per cent in exposed subjects, respectively while in control there were 12 per cent and 28 per cent, respectively. The study revealed that chrysotile asbestos is emitted in the occupational as well as ambient environment that may cause adverse health impact.

Trust and communication as predictors of customer satisfaction in business-to-business relationship marketing in the South African cement manufacturing industry

Directory of Open Access Journals (Sweden)

Phineas Mbango

2015-05-01

Full Text Available Customer satisfaction has become relevant in the South African cement industry as it leads to customer loyalty and cooperation. In the current climate, to ensure long-term profitability, cement suppliers need to adopt strategies to ensure customer satisfaction. This study’s literature search has revealed that there is limited published research, particularly in South Africa, which deals with customer satisfaction determinants in the cement industry. The major objective of the study was to test if trust and communication influence customer satisfaction in the context of business-to-business relationship marketing in the South African cement manufacturing industry. The methodology involved a survey and was quantitative in nature. Data were collected from 362 major business-to-business cement customers throughout South Africa’s nine provinces using the face-to-face interview technique using a seven-point Likert scale structured self-administered questionnaires. The data collected in the empirical study were analysed using descriptive, correlation and regression analysis. The empirical results of this study suggest that, in order to maintain customer satisfaction, a cement supplier has to invest in ways of enhancing customer trust and communication. As a result this study makes both theoretical and practical contribution in the field of relationship marketing

Dynamic technical inefficiency and industrial concentration in the Indonesian food and beverages industry

NARCIS (Netherlands)

Setiawan, Maman; Oude Lansink, Alfons G.J.M.

2018-01-01

Purpose: The purpose of this paper is to investigate the relation between industrial concentration and technical inefficiency in the Indonesian food and beverages industry using a dynamic performance measure (dynamic technical inefficiency) that accounts for the presence of adjustment costs.

Explorations on Energy Management System Standardization in Cement Industry%水泥行业能源管理体系标准进展及实施探索

Institute of Scientific and Technical Information of China (English)

李燕; 王赓; 任香贵

2014-01-01

The energy-saving management of China’s cement industry has gradually improved in recent years;however, cement industry still faces big pressure of facilitating energy conservation and emission reduction. Based on the current development of cement industry, the paper summarizes and analyzes the application and promotion of energy management system (EnMS) standardization in cement industry, then gives a brief introduction to the implementation of related standards and at last explores the positive function of energy management system in enhancing enterprises’ energy management and improving energy performance.

The European cement industry's approach to the use of secondary raw materials and fuels

Energy Technology Data Exchange (ETDEWEB)

Lawton, J.M.

1992-06-01

Position statements prepared by the European cement industry on the use of secondary raw materials and secondary fuels are introduced and presented. The statements indicate the approach of the industry to the use of these materials and, in the wider context, form part of the industry's overall approach to the environment. (Author). 2 refs.

Reaping the carbon rent: Abatement and overallocation profits in the European cement industry, insights from an LMDI decomposition analysis

International Nuclear Information System (INIS)

Branger, Frédéric; Quirion, Philippe

2015-01-01

We analyse variations of carbon emissions in the European cement industry from 1990 to 2012, at the European level (EU 27), and at the national level for six major producers (Germany, France, Spain, the United Kingdom, Italy and Poland). We apply a Log-Mean Divisia Index (LMDI) method, cross-referencing data from three databases: the Getting the Numbers Right (GNR) database developed by the Cement Sustainability Initiative, the European Union Transaction Log (EUTL), and the Eurostat International Trade database. Our decomposition method allows seven channels of emission change to be distinguished: activity, clinker trade, clinker share, alternative fuels, thermal and electrical energy efficiency, and electricity decarbonisation. We find that, apart from a slow trend of emission reductions coming from technological improvements (first from a decrease in the clinker share, then from an increase in alternative fuels), most of the emission change can be attributed to the activity effect. Using counterfactual scenarios, we estimate that the introduction of the EU ETS brought small but positive technological abatement (2.2% ± 1.3% between 2005 and 2012). Moreover, we find that the European cement industry has gained 3.5 billion Euros of “overallocation profits”, mostly due to the slowdown of production. - Highlights: • We analyse variations of carbon emissions in the European cement industry. • We apply a Log-Mean Divisia Index (LMDI) method. • Most of the emission changes can be attributed to the activity effect. • The EU ETS brought small but positive technological abatement. • The European cement industry has gained 3.5 billion Euros of “overallocation profits”

Cement Formation

DEFF Research Database (Denmark)

Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten

2012-01-01

Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid......−liquid reactions are discussed, as are the influences of particles sizes on clinker phase formation. Furthermore, a mechanism for clinker phase formation in an industrial rotary kiln reactor is outlined....

The ovens of the industry of the cement and their contribution to the handling of solid residuals and dangerous

International Nuclear Information System (INIS)

Riveros Rojas, Marcelo

1995-01-01

The substitution of certain row matters in the process of elaboration of the cement, as flying ashes, polluted soils with petroleum, muds of the industry of the petroleum, oxides of the industry of the steel, foundry sand and tires, they can replace until 40% of the necessities of energy of a cement oven contributing to improve the conservation of the environment. This new technology is using with success in United States and some countries of Europe

Industrial Wastes as Alternative Mineral Addition in Portland Cement and as Aggregate in Coating Mortars

OpenAIRE

Oliveira, Kamilla Almeida; Nazário, Bruna Inácio; Oliveira, Antonio Pedro Novaes de; Hotza, Dachamir; Raupp-Pereira, Fabiano

2017-01-01

This paper presents an evaluation study of wastes from pulp and paper as well as construction and demolition industries for application in cement-based materials. The alternative raw materials were used as a source of calcium carbonate (CaCO3) and as pozzolanic material (water-reactive SiO2) in partial replacement of Portland cement. In addition to the hydraulic binder, coating mortars were composed by combining the pulp and paper fluidized bed sand residue with construction and demolition wa...

CO2 Capture by Cement Raw Meal

DEFF Research Database (Denmark)

Pathi, Sharat Kumar; Lin, Weigang; Illerup, Jytte Boll

2013-01-01

The cement industry is one of the major sources of CO2 emissions and is likely to contribute to further increases in the near future. The carbonate looping process has the potential to capture CO2 emissions from the cement industry, in which raw meal for cement production could be used...... as the sorbent. Cyclic experiments were carried out in a TGA apparatus using industrial cement raw meal and synthetic raw meal as sorbents, with limestone as the reference. The results show that the CO2 capture capacities of the cement raw meal and the synthetic raw meal are comparable to those of pure limestone...... that raw meal could be used as a sorbent for the easy integration of the carbonate looping process into the cement pyro process for reducing CO2 emissions from the cement production process....

National Emission Standards for Hazardous Air Pollutants (NESHAP) for the Portland Cement Manufacturing Industry Subpart LLL Rule Guidance

Science.gov (United States)

This Spring 2016 document is intended for the use of EPA staff, State and Local regulatory agencies and their staff, and industry plant managers for the NESHAP for the Portland Cement Manufacturing Industry.

Queue balancing of load and expedition service in a cement industry in Brazil

Directory of Open Access Journals (Sweden)

David Custódio de Sena

2013-11-01

Full Text Available The load and weight process in a cement industry is one of logistic step that shows the biggest time of occurrence, increasing the queues. This study aims to do a scenarios to solve this queue problem. This way, it pretends to find an better resources distribuition.

An outlook into energy consumption in large scale industries in India: The cases of steel, aluminium and cement

International Nuclear Information System (INIS)

Dutta, Monica; Mukherjee, Saptarshi

2010-01-01

All the growth-oriented sectors in a developing economy consume enormous energy in their production processes. Steel, aluminium and cement are the key manufacturing industries in India which provide inputs to various other sectors such as construction, transportation, power transmission, etc. As a result, their demand is consistently rising. These industries are heavily energy-intensive and use raw materials such as iron ore, coal, electricity, steam, and fuel oil, whose supply can act as severe production constraints over a period of time and can hinder sustainable development. Hence it becomes imperative for these industries to continuously innovate more energy efficient techniques. This paper makes a foray into the energy demand for these industries and explores the potential of any future reduction in their energy consumption. The paper offers a projection scenario for 2001-2031 (based on the MARKAL Modeling exercise for India) for possible catching up in reduction in energy consumptions in these sectors under alternative situations. The analysis suggests the existence of some plausible energy efficiency enhancing techniques in these industries. Exploring these options will definitely ensure cost effectiveness and competitiveness of these three key sectors in the global market. -- Research highlights: →Energy reduction potential exists in Indian steel, aluminium and cement sectors and can go up to 8%, 17% and 6% respectively in these sectors in 2031 if appropriate energy saving technologies are introduced and implemented. →In aluminium industry energy reduction potential is huge in fabrication stage in the production process and extensive improvement can be done in terms of energy efficiency in this stage. Cogeneration of power through waste heat recovery, change in norms in standard to take advantage of producing composite cements using more than one industrial waste, like both fly ash and slag are important required changes in Indian cement sector. �

Understanding mineral trioxide aggregate/Portland-cement: a review of literature and background factors.

Science.gov (United States)

Steffen, R; van Waes, H

2009-06-01

This was to carry out a review of the literature concerning mineral trioxide aggregate (MTA) and Portland cement with regards to clinical, biological and mechanical findings and a possible substitution of MTA through Portland cement for endodontic use. Electronic literature search of scientific papers from January 1993 to January 2009 was carried out on the MEDLINE and Scopus databases using specific key words. In total, 57 papers were identified that dealt with MTA and Portland cement in a relevant way. The review of 50 papers conforming to the applied criteria showed that MTA and Portland cements have the same clinical, biological and mechanical properties. In animal experiments and technical characterisations both materials seemed to have very similar properties. The only difference is bismuth oxide in MTA added for better radio opacity. It seems likely that MTA materials are based on industrial Portland cements mixed with bismuth oxide. More studies, especially some long-term studies comparing MTA and Portland cement, are necessary. The existing literature gives a solid base for clinical studies with Portland cement in order to replace MTA as an endodontic material. Portland cement could be a substitute for most endodontic materials used in primary teeth.

Performance of Cement Containing Laterite as Supplementary Cementing Material

Directory of Open Access Journals (Sweden)

Abbas Bukhari, Z. S.

2013-03-01

Full Text Available The utilization of different industrial waste, by-products or other materials such as ground granulated blast furnace slag, silica fume, fly ash, limestone, and kiln dust, etc. as supplemen- tary cementing materials has received considerable attention in recent years. A study has been conducted to look into the performance of laterite as Supplementary Cementing Materials (SCM. The study focuses on compressive strength performance of blended cement containing different percentage of laterite. The cement is replaced accordingly with percentage of 2 %, 5 %, 7 % and 10 % by weight. In addition, the effect of use of three chemically different laterites have been studied on physical performance of cement as in setting time, Le-Chatlier expansion, loss on ignition, insoluble residue, free lime and specifically compressive strength of cement cubes tested at the age of 3, 7, and 28 days. The results show that the strength of cement blended with laterite as SCM is enhanced. Key words: Portland cement, supplementary cementing materials (SCM, laterite, compressive strength KUI – 6/2013 Received January 4, 2012 Accepted February 11, 2013

Critical elements in implementations of just-in-time management: empirical study of cement industry in Pakistan

OpenAIRE

Qureshi, Muhammad Imran; Iftikhar, Mehwish; Bhatti, Mansoor Nazir; Shams, Tauqeer; Zaman, Khalid

2013-01-01

In recent years, inventory management is continuous challenge for all organizations not only due to heavy cost associated with inventory holding, but also it has a great deal to do with the organizations production process. Cement industry is a growing sector of Pakistan?s economy which is now facing problems in capacity utilization of their plants. This study attempts to identify the key strategies for successful implementation of just-in-time (JIT) management philosophy on the cement indust...

Modeling energy efficiency to improve air quality and health effects of China's cement industry

NARCIS (Netherlands)

Zhang, Shaohui; Worrell, Ernst|info:eu-repo/dai/nl/106856715; Crijns-Graus, Wina|info:eu-repo/dai/nl/308005015; Krol, Maarten|info:eu-repo/dai/nl/078760410; de Bruine, Marco|info:eu-repo/dai/nl/411965085; Geng, Guangpo; Wagner, Fabian; Cofala, Janusz

2016-01-01

Actions to reduce the combustion of fossil fuels often decrease GHG emissions as well as air pollutants and bring multiple benefits for improvement of energy efficiency, climate change, and air quality associated with human health benefits. The China's cement industry is the second largest energy

Cement replacement materials. Properties, durability, sustainability

International Nuclear Information System (INIS)

Ramezanianpour, Ali Akbar

2014-01-01

The aim of this book is to present the latest findings in the properties and application of Supplementary Cementing Materials and blended cements currently used in the world in concrete. Sustainability is an important issue all over the world. Carbon dioxide emission has been a serious problem in the world due to the greenhouse effect. Today many countries agreed to reduce the emission of CO2. Many phases of cement and concrete technology can affect sustainability. Cement and concrete industry is responsible for the production of 7% carbon dioxide of the total world CO2 emission. The use of supplementary cementing materials (SCM), design of concrete mixtures with optimum content of cement and enhancement of concrete durability are the main issues towards sustainability in concrete industry.

TECHNOLOGICAL CHANGES IN THE CEMENT MANUFACTURING INDUSTRY.

Science.gov (United States)

WESSON, CARL E.

THE PURPOSE OF THIS STUDY IS TO PRESENT A PRELIMINARY PICTURE OF OCCUPATIONAL CHANGES BROUGHT ABOUT IN THE MANUFACTURE OF CEMENT AS A RESULT OF INTRODUCING AUTOMATED EQUIPMENT. ONE AUTOMATED AND SEVERAL CONVENTIONAL TYPE CEMENT PLANTS WERE STUDIED. ANALYSIS OF DATA OBTAINED THROUGH RESEARCH AND DATA COLLECTED DURING THE STUDY REVEALED THAT…

Substantial global carbon uptake by cement carbonation

OpenAIRE

Xi, Fengming; Davis, Steven J.; Ciais, Philippe; Crawford-Brown, Douglas; Guan, Dabo; Pade, Claus; Shi, Tiemao; Syddall, Mark; Lv, Jie; Ji, Lanzhu; Bing, Longfei; Wang, Jiaoyue; Wei, Wei; Yang, Keun-Hyeok; Lagerblad, Björn

2016-01-01

Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO2 emissions from all industrial process and fossil-fuel combustion in 20131, 2. Considerable attention has been paid to quantifying these industrial process emissions from cement production2, 3, but the natural reversal of the process—carbonation—has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondar...

Impact of Working Capital Management on Firm’s Profitability: A Case Study of Cement Industry of Pakistan

Directory of Open Access Journals (Sweden)

Farrukh Shahzad

2015-02-01

Full Text Available The fundamental purpose behind this study is to exactly test the effect of working capital management on profitability of cement industry of Pakistan. To explore this relationship between these two, the creator gathered auxiliary information from 12 listed firms in Karachi stock exchange (KSC for the time period of 2007-2013. For this reason, in this study we utilize variable of return on assets ratio to gauge the benefit of organization and variables of CR, QR, NCA/TA, WCT and ITR as living up to expectations working capital management criteria. The consequences of the research demonstrate that there is a huge effect of the working capital management on profitability of cement industry of Pakistan. Accordingly, manager may improve the Profitability of their organizations by minimizing the inventory turnover ratio, and by diminishing working capital turnover ratio but there is no impact of expanding or diminishing the current proportion on profitability. Along these lines, the results show that through fitting working capital management the organization can expand its benefit. This study shall be helping hand for the cement industry of Pakistan in the management of their working capital in such an effective way thus, to the point that they can increase their profitability.

Cement Mason's Curriculum. Instructional Units.

Science.gov (United States)

Hendirx, Laborn J.; Patton, Bob

To assist cement mason instructors in providing comprehensive instruction to their students, this curriculum guide treats both the skills and information necessary for cement masons in commercial and industrial construction. Ten sections are included, as follow: related information, covering orientation, safety, the history of cement, and applying…

Technical development of industry for 30 years

International Nuclear Information System (INIS)

2009-01-01

This book mentions the history for 30 years since 1979 on industrial technology, which records change of system and environment of industrial technology development, like economical and social environment, industrial technology policy, support system on technical development and enterprise institute, assignment for future and product of industrial technology by field such as electric electronic, information and communications, machine material and fiber chemistry, and the way which Korea industrial technology association walked on.

The cement recycling of the earthquake disaster debris by Hachinohe Cement Co., Ltd

International Nuclear Information System (INIS)

Kataoka, Masayuki

2015-01-01

A tremendous quantity of earthquake disaster debris and tsunami sediment was resulted by the Great East Japan Earthquake on March 11, 2011. Hachinohe Cement Co., Ltd., a Sumitomo Osaka Cement subsidiary, was the first cement industry company to receive and process such waste materials outside of their usual prefecture area, while the company is performing their treatment and recycling services locally in Hachinohe City and Aomori Prefecture. This report provides an explanation about the recycling mechanism of waste materials and by-products in cement manufacturing process, and introduces an example of actual achievements for the disaster debris treatment by utilizing the cement recycling technologies at the Hachinohe Cement Plant. (author)

Policy Options for Encouraging Energy Efficiency Best Practices in Shandong Province's Cement Industry

Energy Technology Data Exchange (ETDEWEB)

Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sambeek, Emiel van [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yowargana, Ping [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shuang, Liu [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kejun, Jiang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-07-12

This research intends to explore possible design options for a sectoral approach in the cement sector in Shandong Province and to consider its respective advantages and disadvantages for future application. An effort has been made in this research to gather and analyze data that will provide a transparent and robust basis for development of a Business-As-Usual (BAU) scenario, maximum technology potential scenario, and ultimately a sector crediting baseline. Surveys among cement companies and discussions with stakeholders were also conducted in order to better understand the industry and local needs related to the sectoral approach.

Evaluation of cement treated base courses : technical assistance report.

Science.gov (United States)

2000-12-01

The objectives of this project are to determine the strength characteristics of soil cement bases that were constructed under stabilized procedures (DOTD TR 432M/432-99) and the cement treated design philosophy. This was accomplished by using the Fal...

Chemistry of cements for nuclear applications

International Nuclear Information System (INIS)

Barrett, P.; Glasser, F.P.

1992-01-01

In recent times the nuclear industry has thrown up challenges which cannot be met by the application of conventional civil and materials engineering knowledge. The contributions in this volume investigate all aspects of cement performance. The scope of the papers demonstrates the current balance of activities which have as their objective the elucidation of kinetics and immobilization, determining material interactions and of assessing future performance. The papers reflect the varied goals of the sponsors who include national governments, the Commission of the European Communities and the nuclear industries. In six parts attention is paid to the durability of cement and concrete in repository environment; interactions between cement, waste components and ground water; properties and performance of cement materials; leach behavior and mechanisms, diffusional properties of cement and concrete, including porosity-permeability relationships; and thermodynamics of cementitious systems and modelling of cement performance

Technical change in US industry: A cross-industry analysis

Science.gov (United States)

Nelson, R. R. (Editor)

1981-01-01

The nature of the public policies which have influenced the pace and pattern of technical progress in a number of American industries is studied with the view of assessing the broad effects of these policies. The industries studied are agriculture, pharmaceuticals, semiconductors, computers, civil aircraft, automobiles and residential construction. The policies considered include research and development funding as well as government procurement, education, information dissemination, patent protection, licensing, regulations, and anti-trust policies.

Rietveld analysis, powder diffraction and cement

International Nuclear Information System (INIS)

Peterson, V.

2002-01-01

Full text: Phase quantification of cement is essential in its industrial use, however many methods are inaccurate and/or time consuming. Powder diffraction is one of the more accurate techniques used for quantitative phase analysis of cement. There has been an increase in the use of Rietveld refinement and powder diffraction for the analysis and phase quantification of cement and its components in recent years. The complex nature of cement components, existence of solid solutions, polymorphic variation of phases and overlapping phase peaks in diffraction patterns makes phase quantification of cements by powder diffraction difficult. The main phase in cement is alite, a solid solution of tricalcium silicate. Tricalcium silicate has been found to exist in seven modifications in three crystal systems, including triclinic, monoclinic, and rhombohedral structures. Hence, phase quantification of cements using Rietveld methods usually involves the simultaneous modelling of several tricalcium silicate structures to fit the complex alite phase. An industry ordinary Portland cement, industry and standard clinker, and a synthetic tricalcium silicate were characterised using neutron, laboratory x-ray and synchrotron powder diffraction. Diffraction patterns were analysed using full-profile Rietveld refinement. This enabled comparison of x-ray, neutron and synchrotron data for phase quantification of the cement and examination of the tricalcium silicate. Excellent Rietveld fits were achieved, however the results showed that the quantitative phase analysis results differed for some phases in the same clinker sample between various data sources. This presentation will give a short introduction about cement components including polymorphism, followed by the presentation of some problems in phase quantification of cements and the role of Rietveld refinement in solving these problems. Copyright (2002) Australian X-ray Analytical Association Inc

Cement Types, Composition, Uses and Advantages of Nanocement, Environmental Impact on Cement Production, and Possible Solutions

Directory of Open Access Journals (Sweden)

S. P. Dunuweera

2018-01-01

Full Text Available We first discuss cement production and special nomenclature used by cement industrialists in expressing the composition of their cement products. We reveal different types of cement products, their compositions, properties, and typical uses. Wherever possible, we tend to give reasons as to why a particular cement type is more suitable for a given purpose than other types. Cement manufacturing processes are associated with emissions of large quantities of greenhouse gases and environmental pollutants. We give below quantitative and qualitative analyses of environmental impact of cement manufacturing. Controlling pollution is a mandatory legal and social requirement pertinent to any industry. As cement industry is one of the biggest CO2 emitters, it is appropriate to discuss different ways and means of CO2 capture, which will be done next. Finally, we give an account of production of nanocement and advantages associated with nanocement. Nanofillers such as nanotitania, nanosilica, and nanoalumina can be produced in large industrial scale via top-down approach of reducing size of naturally available bulk raw materials to those in the nanorange of 1 nm–100 nm. We mention the preparation of nanotitania and nanosilica from Sri Lankan mineral sands and quartz deposits, respectively, for the use as additives in cement products to improve performance and reduce the amount and cost of cement production and consequent environmental impacts. As of now, mineral sands and other treasures of minerals are exported without much value addition. Simple chemical modifications or physical treatments would add enormous value to these natural materials. Sri Lanka is gifted with highly pure quartz and graphite from which silica and graphite nanoparticles, respectively, can be prepared by simple size reduction processes. These can be used as additives in cements. Separation of constituents of mineral sands is already an ongoing process.

Advanced Technical Drafting (Industrial Arts) Curriculum Guide. Bulletin 1751.

Science.gov (United States)

Louisiana State Dept. of Education, Baton Rouge. Div. of Vocational Education.

This curriculum guide contains materials for a 17-unit course in advanced technical drafting, a followup to the basic technical drafting course in the industrial arts curriculum for grades 10-12. It is intended for use by industrial arts teachers, supervisors, counselors, administrators, and teacher educators. A three-page course overview provides…

Investigating different factors influencing job satisfaction: A case study of cement industry

OpenAIRE

Mina Shirvani; Asghar Mohammadi; Mohammad Reza Iravani; Saeed Yousef Pour; Allahyar Arabmomeni; Shirin Mirhaj; Akram Fakhri Fakhramini

2013-01-01

Job satisfaction plays an important role on increasing business productivity and efficiency. This paper presents an empirical investigation to study the relationship between job satisfaction and employees’ personal characteristics including gender, marital status, etc. The proposed study designs a questionnaire and distributes it among 244 out of 800 employees who worked for cement industry in Iran. The data are analyzed using different statistical tests such as t-student and analysis of vari...

Evaluation of ternary blended cements for use in transportation concrete structures

Science.gov (United States)

Gilliland, Amanda Louise

This thesis investigates the use of ternary blended cement concrete mixtures for transportation structures. The study documents technical properties of three concrete mixtures used in federally funded transportation projects in Utah, Kansas, and Michigan that used ternary blended cement concrete mixtures. Data were also collected from laboratory trial batches of ternary blended cement concrete mixtures with mixture designs similar to those of the field projects. The study presents the technical, economic, and environmental advantages of ternary blended cement mixtures. Different barriers of implementation for using ternary blended cement concrete mixtures in transportation projects are addressed. It was concluded that there are no technical, economic, or environmental barriers that exist when using most ternary blended cement concrete mixtures. The technical performance of the ternary blended concrete mixtures that were studied was always better than ordinary portland cement concrete mixtures. The ternary blended cements showed increased durability against chloride ion penetration, alkali silica reaction, and reaction to sulfates. These blends also had less linear shrinkage than ordinary portland cement concrete and met all strength requirements. The increased durability would likely reduce life cycle costs associated with concrete pavement and concrete bridge decks. The initial cost of ternary mixtures can be higher or lower than ordinary portland cement, depending on the supplementary cementitious materials used. Ternary blended cement concrete mixtures produce less carbon dioxide emissions than ordinary portland cement mixtures. This reduces the carbon footprint of construction projects. The barriers associated with implementing ternary blended cement concrete for transportation projects are not significant. Supplying fly ash returns any investment costs for the ready mix plant, including silos and other associated equipment. State specifications can make

Captive power plant selection for pakistan cement industry in perspective of current energy crises: a fuzzy-ahp approach

International Nuclear Information System (INIS)

Ali, H.M.; Sultan, A.; Rana, B.B.

2017-01-01

Based on the prevailing energy crisis, it is reasonable for the Cement industry of Pakistan to look for alternate sources of electricity generation. The decision of selecting a CPP (Captive Power Plant) depends on a broad variety of parameters which may be conflicting to each other. A comparative evaluation of these CPP's should be helpful for industry, particularly if the applied methodology can handle with the real world ambiguities and imprecisions associated with the data pools and expert opinions. This paper utilizes an F-AHP (Fuzzy Analytical Hierarchy Process) based multi-attribute framework to prioritize the affecting parameters and assign rankings to the CPP alternatives. The CPP's recommended by experts for this study are RDF-CPP (Refused Derived Fuel CPP), CF-CPP (Coal Fired CPP) and WHR-CPP (Waste Heat Recovery CPP). The factors affecting the decision of selecting the optimum CPP are prioritized by the experts using our F-AHP approach. Real world quantitative data is extracted from different online resources and financial reports of cement companies in Pakistan. The F-AHP model is flexible enough to deal with a variety of inputs including qualitative scales, crisp values and standard fuzzy numbers. The model is solved and a sensitivity analysis is performed in respective software. This study shows that non-conventional CPPs are highly demanded for cement industry in Pakistan and while selecting these CPPs, management gives high priority to factors like 'automation' and 'environment' whereas associated "initial cost"is not given much weight in decision making. In concluding ranking list, WHR-CPP is at the top and CF-CPP is at the bottom. This study may facilitate decision makers of cement industry in Pakistan and international CPP manufacturers alike in their forthcoming strategic decisions. (author)

Solidification process for toxic and hazardous wastes. Second part: Cement solidification matrices; Inertizzazione di rifiuti tossici e nocivi (RTN). Parte seconda: Inertizzazione in matrici cementizie

Energy Technology Data Exchange (ETDEWEB)

Donato, A; Arcuri, L; Dotti, M; Pace, A; Pietrelli, L; Ricci, G [ENEA - Dipartimento Ciclo del Combustibile, Centro Ricerche Energia, Casaccia (Italy); Basta, M; Cali, V; Pagliai, V [ENEA - Dipartimento Ciclo del Combustibile, Centro Ricerche Energia, Saluggia (Italy)

1989-05-15

This paper reports the second part of a general study carried out at the Nuclear Fuel Division aiming at verifying the possible application of the radioactive waste solidification processes to industrial hazardous wastes (RTN). The cement solidification of several RTN types has been taken into consideration, both from the technical and from the economic point of view. After a short examination of the Italian juridical and economical situation in the field, which demonstrates the need of the RTN solidification, the origin and characteristics of the RTN considered in the study and directly provided by the producing industries are reviewed. The laboratory experimental results of the cementation of RTN produced by gold manufacturing industries and by galvanic industries are reported. The cementation process can be considered a very effective mean for reducing both the RTN management costs and the environmental impact of RTN disposal. (author)

Renewable and dangerous residues as industrial fuels. Study about hard environmental support in the cement production in Brazil, years 1990

International Nuclear Information System (INIS)

Santi, Auxiliadora Maria Moura; Seva Filho, Arsenio Oswaldo

1999-01-01

The aim of the work is to indicate new fuels to Brazilian cement industry. A comparative study is presented. The renewable energetic sources, not renewable energetic sources, and residues of other industrial processes are analyzed

Cement manufacture and the environment - Part I: Chemistry and technology

Science.gov (United States)

Van Oss, H. G.; Padovani, A.C.

2002-01-01

Hydraulic (chiefly portland) cement is the binding agent in concrete and mortar and thus a key component of a country's construction sector. Concrete is arguably the most abundant of all manufactured solid materials. Portland cement is made primarily from finely ground clinker, which itself is composed dominantly of hydraulically active calcium silicate minerals formed through high-temperature burning of limestone and other materials in a kiln. This process requires approximately 1.7 tons of raw materials perton of clinker produced and yields about 1 ton of carbon dioxide (CO2) emissions, of which calcination of limestone and the combustion of fuels each contribute about half. The overall level of CO2 output makes the cement industry one of the top two manufacturing industry sources of greenhouse gases; however, in many countries, the cement industry's contribution is a small fraction of that from fossil fuel combustion by power plants and motor vehicles. The nature of clinker and the enormous heat requirements of its manufacture allow the cement industry to consume a wide variety of waste raw materials and fuels, thus providing the opportunity to apply key concepts of industrial ecology, most notably the closing of loops through the use of by-products of other industries (industrial symbiosis). In this article, the chemistry and technology of cement manufacture are summarized. In a forthcoming companion article (part II), some of the environmental challenges and opportunities facing the cement industry are described. Because of the size and scope of the U.S. cement industry, the analysis relies primarily on data and practices from the United States.

Application of Carbonate Looping to Cement Industry

DEFF Research Database (Denmark)

Lin, Weigang; Illerup, Jytte Boll; Dam-Johansen, Kim

2012-01-01

In the present work, cycle experiments of different types of limestone, cement raw meal and a mixture of limestone and clay were carried out in laboratory scale setups at more realistic conditions (i.e. calcination temperature is 950°C and CO2 concentration is 80%) to simulate the performance...... with an increase in the CO2 partial pressure during calcination, indicating enhancement of sintering by the presence of CO2. As sorbents, cement raw meal and the mixture of limestone and clay show a similar trend as limestone with respect to the decay of the CO2 carrying capacity and this capacity is lower than...... that of limestone at the same conditions in most cases. SEM and XRD analyses indicate that a combination of severe sintering and formation of calcium silicates attributes to the poor performance of the cement raw meal....

Reducing cement's CO2 footprint

Science.gov (United States)

van Oss, Hendrik G.

2011-01-01

The manufacturing process for Portland cement causes high levels of greenhouse gas emissions. However, environmental impacts can be reduced by using more energy-efficient kilns and replacing fossil energy with alternative fuels. Although carbon capture and new cements with less CO2 emission are still in the experimental phase, all these innovations can help develop a cleaner cement industry.

Compressive Strength and Physical Properties Behavior of Cement Mortars with addition of Cement Klin Dust

OpenAIRE

Auday A Mehatlaf

2017-01-01

Cement Klin Dust (CKD) was the waste of almost cement industry factories, so that in this paper utilization of CKD as filler in cement and/or concrete was the main objective. CKD from the Karbala cement factory had been used and analysis to know the chemical composition of the oxides was done. In this paper cement mortars with different weight percentages of CKD (0,5,10,20,30,40) had been prepared. Physical properties such as density and porosity were done in different age curing (3, 7, 28) d...

76 FR 28318 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-05-17

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY... Emission Standards for Hazardous Air Pollutants from the Portland Cement Manufacturing Industry Response to... by the Portland Cement Industry and the New Source Performance Standards for Portland Cement Plants...

76 FR 2832 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-01-18

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY...) from the Portland Cement Manufacturing Industry and Standards of Performance (NSPS) for Portland Cement... Standards for Hazardous Air Pollutant From the Portland Cement Manufacturing Industry Docket, Docket ID No...

Carbonate Looping for De-Carbonization of Cement Plants

DEFF Research Database (Denmark)

Pathi, Sharat Kumar; Andersen, Maria Friberg; Lin, Weigang

2011-01-01

Cement industry is one of the largest emitter of CO2 other than power generation plants, which includes the emissions from combustion of fuel and also from calcination of limestone for clinker production. In order to reduce CO2 emissions from the cement industry an effective an economically...... feasible technology is to be developed. The carbonate looping process is a promising technology, which is particularly suitable for the cement industry as limestone could be used for capture and release of CO2. Integration of carbonate looping process into cement pyroprocess has two advantages: 1...... integrated into cement pyro-process. The energy required for regeneration in the calciner increases with increase in average conversion of calcined limestone and energy that can be extracted from carbonator decreases with increasing average conversion. Further the influence of type of limestone...

An investigation on the technical standard strategy for China's manufacturing industry

International Nuclear Information System (INIS)

Ma Limin; Jiang Xiangqian; Xu Zhengao; Li Zhu

2005-01-01

China's manufacturing industry is now the 4th largest manufacturing power in the world, second only to the US, Japan, and Germany. Large but not strong, it is still way behind developed countries. In the technical standard field, the gap between China's manufacturing industry and industrially developed countries is showing that there is a low level of technological standards and lack of professional talent versed in technical standards. A technical standards strategy is of importance to the development of China's manufacturing industry has been as one of the major strategies in the 10th Five-Year Plan period. The overall objective of the strategy for China's technical standards should be capable of supporting Chinese enterprises and products in entering the international market and ensuring the superiority of China's key industries in international competition. The implementing tactics of the strategy are all-round tracking, effective adoption, crucial participation, and strong dominance

Supplier selection in supply chain management using analytical network process for Indonesian cement industry

Science.gov (United States)

Ismail, A. H.; Mahardika, R. Z. Z.

2017-12-01

Supply chain management has increased more significance with the impact of globalization. In the present worldwide market, well-managed supply chain is a standout amongst the most vital requirement to be more competitive in the market. For any organization incorporate cement industry, the most critical decision in initial process of supply chain management is to buy products, materials or services from suppliers. So the role of suppliers is irrefutable important in the global aggressive markets. Appropriate decision of supplier selection can lead to reducing cost in supply chain management. However, it is becoming more complex because of existing various criteria and involving the suitable experts in the company to make valid decision in accordance with its criteria. In this study, the supplier selection of an Indonesia’s leading cement company is analyzed by using one of the popular multi-criteria decision making method, Saaty’s analytical network process (ANP). It is employed for the selection of the best alternative among three suppliers of pasted bag. Supplier with the highest rank comes from several major steps from building the relationship between various criteria to rating the alternatives with the help of experts from the company. The results show that, Communication capability, Flexible payment terms, Ability to meet delivery quantities are the most important criteria in the pasted bag supplier selection in Indonesian cement industry with 0.155, 0.110 and 0.1 ANP coefficient respectively. And based on the ANP coefficient values in limit supermatrix, the A2 or supplier 2 had the highest score with 64.7% or 0.13 ANP coefficient.

PIXE characterization of by-products resulting from the zinc recycling of industrial cemented carbides

International Nuclear Information System (INIS)

Freemantle, C.S.; Sacks, N.; Topic, M.; Pineda-Vargas, C.A.

2015-01-01

By-product materials of the widely used zinc recycling process of cemented carbides have been studied. Scanning electron microscopy and micro-PIXE techniques have identified elemental concentrations, distributions and purity of by-product materials from an industrial zinc recycling plant. Cobalt surface enrichment, lamellar microstructures of varying composition, including alternating tungsten carbide (WC) grains and globular cobalt, and regions of excess zinc contamination were found in materials with incomplete zinc penetration. Liquid Co–Zn formation occurred above 72 wt.% Zn at the furnace temperature of 930 °C, and was extracted towards the surface of poorly zinc infiltrated material, primarily by the vacuum used for zinc distillation. Surface enrichment was not observed in material that was zinc infiltrated to the sample center, which was more friable and exhibited more homogeneous porosity and elemental concentrations. The result of incomplete zinc infiltration was an enriched surface zone of up to 60 wt.% Co, compared to an original sample composition of ∼10–15 wt.% Co. The impact on resulting powders could be higher or inhomogeneous cobalt content, as well as unacceptably high zinc concentrations. PIXE has proven it can be a powerful technique for solving industrial problems in the cemented carbide cutting tool industry, by identifying trace elements and their locations (such as Zn to 0.1 wt.% accuracy), as well as the distribution of major elements within WC–Co materials.

PIXE characterization of by-products resulting from the zinc recycling of industrial cemented carbides

Energy Technology Data Exchange (ETDEWEB)

Freemantle, C.S. [School of Chemical & Metallurgical Engineering and DST-NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, P/Bag 3, Wits 2050 (South Africa); Pilot Tools (Pty) (Ltd), P.O. Box 27420, Benrose 2011 (South Africa); Sacks, N. [School of Chemical & Metallurgical Engineering and DST-NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, P/Bag 3, Wits 2050 (South Africa); Topic, M. [iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129 (South Africa); Pineda-Vargas, C.A. [iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129 (South Africa); Faculty of Health & Wellness Sciences, CPUT, Bellville (South Africa)

2015-11-15

By-product materials of the widely used zinc recycling process of cemented carbides have been studied. Scanning electron microscopy and micro-PIXE techniques have identified elemental concentrations, distributions and purity of by-product materials from an industrial zinc recycling plant. Cobalt surface enrichment, lamellar microstructures of varying composition, including alternating tungsten carbide (WC) grains and globular cobalt, and regions of excess zinc contamination were found in materials with incomplete zinc penetration. Liquid Co–Zn formation occurred above 72 wt.% Zn at the furnace temperature of 930 °C, and was extracted towards the surface of poorly zinc infiltrated material, primarily by the vacuum used for zinc distillation. Surface enrichment was not observed in material that was zinc infiltrated to the sample center, which was more friable and exhibited more homogeneous porosity and elemental concentrations. The result of incomplete zinc infiltration was an enriched surface zone of up to 60 wt.% Co, compared to an original sample composition of ∼10–15 wt.% Co. The impact on resulting powders could be higher or inhomogeneous cobalt content, as well as unacceptably high zinc concentrations. PIXE has proven it can be a powerful technique for solving industrial problems in the cemented carbide cutting tool industry, by identifying trace elements and their locations (such as Zn to 0.1 wt.% accuracy), as well as the distribution of major elements within WC–Co materials.

Synthesis of Portland cement and calcium sulfoaluminate-belite cement for sustainable development and performance

Science.gov (United States)

Chen, Irvin Allen

Portland cement concrete, the most widely used manufactured material in the world, is made primarily from water, mineral aggregates, and portland cement. The production of portland cement is energy intensive, accounting for 2% of primary energy consumption and 5% of industrial energy consumption globally. Moreover, portland cement manufacturing contributes significantly to greenhouse gases and accounts for 5% of the global CO2 emissions resulting from human activity. The primary objective of this research was to explore methods of reducing the environmental impact of cement production while maintaining or improving current performance standards. Two approaches were taken, (1) incorporation of waste materials in portland cement synthesis, and (2) optimization of an alternative environmental friendly binder, calcium sulfoaluminate-belite cement. These approaches can lead to less energy consumption, less emission of CO2, and more reuse of industrial waste materials for cement manufacturing. In the portland cement part of the research, portland cement clinkers conforming to the compositional specifications in ASTM C 150 for Type I cement were successfully synthesized from reagent-grade chemicals with 0% to 40% fly ash and 0% to 60% slag incorporation (with 10% intervals), 72.5% limestone with 27.5% fly ash, and 65% limestone with 35% slag. The synthesized portland cements had similar early-age hydration behavior to commercial portland cement. However, waste materials significantly affected cement phase formation. The C3S--C2S ratio decreased with increasing amounts of waste materials incorporated. These differences could have implications on proportioning of raw materials for cement production when using waste materials. In the calcium sulfoaluminate-belite cement part of the research, three calcium sulfoaluminate-belite cement clinkers with a range of phase compositions were successfully synthesized from reagent-grade chemicals. The synthesized calcium sulfoaluminate

Industrial espionage and technical surveillance counter measurers

CERN Document Server

Androulidakis, Iosif

2016-01-01

This book examines technical aspects of industrial espionage and its impact in modern companies, organizations, and individuals while emphasizing the importance of intellectual property in the information era. The authors discuss the problem itself and then provide statistics and real world cases. The main contribution provides a detailed discussion of the actual equipment, tools and techniques concerning technical surveillance in the framework of espionage. Moreover, they present the best practices and methods of detection (technical surveillance counter measures) as well as means of intellectual property protection.

The application of CFD modelling to support the reduction of CO2 emissions in cement industry

International Nuclear Information System (INIS)

Mikulčić, Hrvoje; Vujanović, Milan; Fidaros, Dimitris K.; Priesching, Peter; Minić, Ivica; Tatschl, Reinhard; Duić, Neven; Stefanović, Gordana

2012-01-01

The cement industry is one of the leading producers of anthropogenic greenhouse gases, of which CO 2 is the most significant. Recently, researchers have invested a considerable amount of time studying ways to improve energy consumption and pollutant formation in the overall cement manufacturing process. One idea involves dividing the calcination and clinkering processes into two separate furnaces. The calcination process is performed in a calciner while the clinkering process takes place in a rotary kiln. As this is new technology in the cement manufacturing process, calciners are still in the research and development phase. The purpose of this paper is to demonstrate the potential of CFD to support the design and optimization of calciners, whose use appears to be essential in reduction of CO 2 emission during cement production. The mathematical model of the calcination process was developed, validated and implemented into a commercial CFD code, which was then used for the analysis. From the results obtained by these simulations, researchers will gain an in-depth understanding of all thermo-chemical reactions in a calciner. This understanding can be used to optimize the calciner's geometry, to make production more efficient, to lower pollutant formation and to subsequently reduce greenhouse gas emissions. -- Highlights: ► The potential of CO 2 emissions reduction, by using a cement calciner was presented. ► When a cement calciner is used, CO 2 emissions reduction of 3–4% can be achieved. ► The calcination model was developed, validated, and then used for the analysis. ► Shown method can be applied for investigation and optimization of cement calciners.

Development of high-performance blended cements

Science.gov (United States)

Wu, Zichao

2000-10-01

This thesis presents the development of high-performance blended cements from industrial by-products. To overcome the low-early strength of blended cements, several chemicals were studied as the activators for cement hydration. Sodium sulfate was discovered as the best activator. The blending proportions were optimized by Taguchi experimental design. The optimized blended cements containing up to 80% fly ash performed better than Type I cement in strength development and durability. Maintaining a constant cement content, concrete produced from the optimized blended cements had equal or higher strength and higher durability than that produced from Type I cement alone. The key for the activation mechanism was the reaction between added SO4 2- and Ca2+ dissolved from cement hydration products.

Integer programming of cement distribution by train

Science.gov (United States)

Indarsih

2018-01-01

Cement industry in Central Java distributes cement by train to meet daily demand in Yogyakarta and Central Java area. There are five destination stations. For each destination station, there is a warehouse to load cements. Decision maker of cement industry have a plan to redesign the infrastructure and transportation system. The aim is to determine how many locomotives, train wagons, and containers and how to arrange train schedules with subject to the delivery time. For this purposes, we consider an integer programming to minimize the total of operational cost. Further, we will discuss a case study and the solution the problem can be calculated by LINGO software.

Cement analysis using d + D neutrons

International Nuclear Information System (INIS)

Womble, Phillip C.; Paschal, Jon; Moore, Ryan

2005-01-01

In the cement industry, the primary concern is quality control. The earlier the cement industry can institute quality control upon their product, the more significant their savings in labor, energy and material. We are developing a prototype cement analyzer using pulsed neutrons from a d-D electronic neutron generator with the goal of ensuring quality control of cement in an on-line manner. By utilizing a low intensity d-D neutron source and a specially-designed moderator assembly, we are able to produce one of the safest neutron-based systems in the market. Also, this design includes some exciting new methods of data acquisition which may substantially reduce the final installation costs. In our proof-of-principle measurements, we were able to measure the primary components of cement (Al, Si, Ca and Fe) to limits required for the raw materials, the derived mixes and the clinkers utilizing this neutron generator

Energetic and exergetic analysis of waste heat recovery systems in the cement industry

International Nuclear Information System (INIS)

Karellas, S.; Leontaritis, A.-D.; Panousis, G.; Bellos, E.; Kakaras, E.

2013-01-01

In a typical cement producing procedure, 25% of the total energy used is electricity and 75% is thermal energy. However, the process is characterized by significant heat losses mainly by the flue gases and the ambient air stream used for cooling down the clinker (about 35%–40% of the process heat loss). Approximately 26% of the heat input to the system is lost due to dust, clinker discharge, radiation and convection losses from the kiln and the preheaters. A heat recovery system could be used to increase the efficiency of the cement plant and thus contribute to emissions decrease. The aim of this paper is to examine and compare energetically and exergetically, two different WHR (waste heat recovery) methods: a water-steam Rankine cycle, and an Organic Rankine Cycle (ORC). A parametric study proved that the water steam technology is more efficient than ORC in exhaust gases temperature higher than 310 °C. Finally a brief economic assessment of the most efficient solution was implemented. WHR installations in cement industry can contribute significantly in the reduction of the electrical consumptions operating cost thus being a very attractive investment with a payback period up to 5 years. - Highlights: • This paper presents waste heat recovery as a way to gain energy from the exhaust gases in a cement plant. • Water steam cycle and ORC has been analyzed for waste heat recovery. • The energetic and exergetic evaluation of the two waste heat recovery processes is presented and compared

Some technical writing skills industry needs

Science.gov (United States)

Smith, F. R.

1981-01-01

It is suggested that engineers and other technical students be taught three classes of skills in technical writing. First, "Big Picture Things", which includes: the importance of clear writing, the wide scope of writing, the wide scope of writing tasks that will be faced in industry, and the principles of organization of technical materials such as; how to analyze, classify, partition, and interpret. Second, "Writing Procedures", which encompasses: how to get words on paper efficiently and team-write. Third, "Writing Details", in which two considerations are important: how to achieve precision in the use of language and the aspects of style. Three problems in style are cited: the problem of sentence transition, overuse of attributive adjectives, and verbosity in paragraph structure. The most important thing in technical writing is considered to be functionality, economy and clarity.

Combustion of Sewage Sludge as Alternative Fuel for Cement Industry

Institute of Scientific and Technical Information of China (English)

LI Fuzhou; ZHANG Wei

2011-01-01

The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of sewage sludge and coal, and non-isothermal kinetics analysis method was applied to evaluate the combustion process. Based on Coats-Redfem integral method, some reaction models were tested,the mechanism and kinetics of the combustion reaction were discussed. The results show that the combustion of sewage sludge is mainly in the Iow temperature stage, meanwhile the ignition temperature and Arrhenius activation energy are lower than that of coal. The combustion of sewage sludge has the advantage over coal in some aspects, thus sewage sludge can partly replace coal used as cement industry fuel.

Methodological and Practical Considerations for DevelopingMultiproject Baselines for Electric Power and Cement Industry Projects inCentral America

Energy Technology Data Exchange (ETDEWEB)

Murtishaw, Scott; Sathaye, Jayant; Galitsky, Christina; Dorion,Kristel

2004-09-02

The Lawrence Berkeley National Laboratory (Berkeley Lab) andthe Center for Sustainable Development in the Americas (CSDA) conductedtechnical studies and organized two training workshops to developcapacity in Central America for the evaluation of climate changeprojects. This paper describes the results of two baseline case studiesconducted for these workshops, one for the power sector and one for thecement industry, that were devised to illustrate certain approaches tobaseline setting. Multiproject baseline emission rates (BERs) for themain Guatemalan electricity grid were calculated from 2001 data. Inrecent years, the Guatemalan power sector has experienced rapid growth;thus, a sufficient number of new plants have been built to estimateviable BERs. We found that BERs for baseload plants offsetting additionalbaseload capacity ranged from 0.702 kgCO2/kWh (using a weighted averagestringency) to 0.507 kgCO2/kWh (using a 10th percentile stringency),while the baseline for plants offsetting load-followingcapacity is lowerat 0.567 kgCO2/kWh. For power displaced from existing load-followingplants, the rate is higher, 0.735 kgCO2/kWh, as a result of the age ofsome plants used for meeting peak loads and the infrequency of their use.The approved consolidated methodology for the Clean Development Mechanismyields a single rate of 0.753 kgCO2/kWh. Due to the relatively smallnumber of cement plants in the region and the regional nature of thecement market, all of Central America was chosen as the geographicboundary for setting cement industry BERs. Unfortunately, actualoperations and output data were unobtainable for most of the plants inthe region, and many data were estimated. Cement industry BERs rangedfrom 205 kgCO2 to 225 kgCO2 per metric ton of cement.

76 FR 2860 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-01-18

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY... Portland Cement Manufacturing Industry Docket, Docket ID No. EPA-HQ-OAR-2002-0051, 1200 Pennsylvania Ave... Portland Cement Manufacturing Industry Docket, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington...

Colorectal cancer and non-malignant respiratory disease in asbestos cement and cement workers

International Nuclear Information System (INIS)

Jacobsson, K.

1993-09-01

Radiologically visible parenchymal changes (small opacities >= 1/0;ILO 1980 classification) were present in 20% of a sample of workers (N=174), employed for 20 years (median) in an asbestos cement plant. Exposure-response relationships were found, after controlling for age and smoking habits. In a sample of asbestos cement workers with symptoms and signs suggestive of pulmonary disease (N=33), increased lung density measured by x-ray computed tomography, and reduced static lung volumes and lung compliance was found. In a cohort of asbestos cement workers (N=1.929) with an estimated median exposure of 1.2 fibres/ml, the mortality from non-malignant respiratory disease was increased in comparison to a regional reference cohort (N=1.233). A two-to three-fold increase of non-malignant respiratory mortality was noted among workers employed for more than a decade in the asbestos cement plant, compared to cement workers (N=1.526), who in their turn did not experience and increased risk compared to the general population. In the cohorts of asbestos cement and cement workers, there was a tow-to three-fold increased incidence of cancer in the right part of the colon, compared to the general population as well as to external reference cohorts of other industrial workers (N=3.965) and fishermen (N=8.092). A causal relation with the exposure to mineral dust and fibres was supported by the findings of higher risk estimated in subgroups with high cumulated asbestos doses or longer duration of cement work. The incidence of cancer in the left part of the colon was not increased. Morbidity data, but not mortality data, disclosed the subsite-specific risk pattern. Both asbestos cement workers and cement workers has an increased incidence of rectal cancer, compared with the general population, and with the fishermen. The risk was, however, of the same magnitude among the other industrial workers. 181 refs

Use of cement in concrete according to European standard EN 206-1

Directory of Open Access Journals (Sweden)

Christoph Müller

2012-04-01

Full Text Available The manufacture of cements with several main constituents (blended cements is of particular importance with regard to reducing climatically relevant CO2 emissions in the cement industry. A wide variety of common cement products exists in the different EU Member States. They match local manufacturing conditions, throughout meeting particular climatic or other local conditions, including building practices. In general, all cements conforming to European Cement Standard EN 197-1 are suitable for the manufacture of concrete according to European Concrete Standard EN 206-1. Depending on the area of application, however, differences related to the cement type may possibly have to be taken into account to ensure the durability of the concretes manufactured with these cements. These regulations were laid down in National Application Documents (NADs to EN 206-1 dependent upon the exposure classes that a structural element is assigned to. This paper deals with the overall concept of EN 206-1 with regard to concrete durability. It gives an overview of the cement types used in Europe and the areas of application of cements conforming to EN 197-1 in concrete conforming to EN 206-1 and various national annexes. The option of combining several main constituents makes blended cements particularly well suited for combining the advantages of individual main constituents, and thus for developing these cements into even more robust systems. This process requires an integrated assessment of all requirements to be met by cements during manufacture and application. From a technical perspective these include the strength formation potential as well as good workability of the concrete and, in particular, the durability of the concrete made from these cements. The effects that the main constituents have with regard to properties relevant to durability can be utilized in particular in cements made from a combination of limestone/blastfurnace slag or limestone/fly ash as

The Tournemire industrial analogue: reactive-transport modelling of cement-clay interfaces

International Nuclear Information System (INIS)

Watson, C.; Wilson, J.; Benbow, S.; Savage, D.; Walker, C.; Norris, S.

2012-01-01

Document available in extended abstract form only. In a number of concepts for geological disposal facilities (GDFs) for radioactive waste, cement-based materials are used for a variety of purposes including mechanical support, backfilling of cavities, grouting of fractures in the host rock, and immobilisation of radionuclides in waste-forms. Such facilities will ultimately re-saturate with encroaching groundwater, at which point leaching of the cement components is likely to give rise to an alkaline pore fluid, regardless of cement type. This pore fluid will be in disequilibrium with both the host rock and other engineered barrier system (EBS) materials used in the construction of the facility, such as bentonite. The interaction of the pore fluid could lead, for example, to the reduction in the swelling capacity of the clay, alteration of porosity and permeability both in the host rock and in EBS materials, and reduction of sorption capacities. Analogue systems can provide information about hyper-alkaline alteration that it is not possible to obtain from short-term experimental studies alone, because they have evolved in situ over many tens, hundreds or thousands of years. These systems can be used to improve scientific understanding and consequently mathematical models, which in turn can be used to simulate the performance of the engineered and natural materials over the lifetime of the GDF. Industrial analogues provide a kind of 'halfway house' between natural analogues and laboratory experimental studies; the initial and boundary conditions are often better understood than natural analogues, and the timescales involved, whilst much shorter than natural analogues, are generally of much greater duration than laboratory studies. One such analogue can be found at Tournemire, southern France, where a tunnel excavated in the 1880's had several exploration boreholes drilled into its basement in the 1990's. These boreholes were then filled with concrete and cement

Coal-Mining Tailings as a Pozzolanic Material in Cements Industry

Directory of Open Access Journals (Sweden)

Santiago Yagüe

2018-01-01

Full Text Available The generation of enormous volumes of mine-tailing waste is standard practice in the mining industry. Large quantities of these tailings are also sources of kaolinite-rich materials that accumulate in slag heaps, causing significant environmental degradation and visual impacts on the landscape. The consequences of coal refuse dumped in slagheaps calls for the study of eco-innovative solutions and the assessment of waste types. Moreover, the environmental benefits of reusing large amounts of contaminated waste are also evident. Hence, the objective of this investigation is to expand current knowledge of new siliceous-aluminium minerals and their pozzolanic activity. Four raw tailing samples are characterized to determine their chemical (by ICP/MS analysis, morphological (by SEM/EDX analysis, and mineralogical (by XRD analysis compositions prior to their thermal activation that transforms the inert wastes at various temperatures into materials with cementitious properties. The results of XRD analysis following activation confirmed that the kaolinite content is fully transformed into metakaolinite. The coal refuse samples presented sufficiently reliable levels of pozzolanic activity for use as additives in industrial cements.

Exergetic life cycle assessment of cement production process with waste heat power generation

International Nuclear Information System (INIS)

Sui, Xiuwen; Zhang, Yun; Shao, Shuai; Zhang, Shushen

2014-01-01

Highlights: • Exergetic life cycle assessment was performed for the cement production process. • Each system’s efficiency before and after waste heat power generation was analyzed. • The waste heat power generation improved the efficiency of each production system. • It provided technical support for the implementation of energy-saving schemes. - Abstract: The cement industry is an industry that consumes a considerable quantity of resources and energy and has a very large influence on the efficient use of global resources and energy. In this study, exergetic life cycle assessment is performed for the cement production process, and the energy efficiency and exergy efficiency of each system before and after waste heat power generation is investigated. The study indicates that, before carrying out a waste heat power generation project, the objective energy efficiencies of the raw material preparation system, pulverized coal preparation system and rotary kiln system are 39.4%, 10.8% and 50.2%, respectively, and the objective exergy efficiencies are 4.5%, 1.4% and 33.7%, respectively; after carrying out a waste heat power generation project, the objective energy efficiencies are 45.8%, 15.5% and 55.1%, respectively, and the objective exergy efficiencies are 7.8%, 2.8% and 38.1%, respectively. The waste heat power generation project can recover 3.7% of the total input exergy of a rotary kiln system and improve the objective exergy efficiencies of the above three systems. The study can identify degree of resource and energy utilization and the energy-saving effect of a waste heat power generation project on each system, and provide technical support for managers in the implementation of energy-saving schemes

Assessment of Energy Performance and Emission Control Using Alternative Fuels in Cement Industry through a Process Model

Directory of Open Access Journals (Sweden)

Azad Rahman

2017-12-01

Full Text Available Cement manufacturing is one of the most energy intensive processes and is accountable for substantial pollutant emissions. Increasing energy costs compel stakeholders and researchers to search for alternative options to improve energy performance and reduce CO2 emissions. Alternative fuels offer a realistic solution towards the reduction of the usage of fossil fuels and the mitigation of pollutant emissions. This paper developed a process model of a precalciner kiln system in the cement industry using Aspen Plus software to simulate the effect of five alternative fuels on pollutant emissions and energy performance. The alternatives fuels used were tyre, municipal solid waste (MSW, meat and bone meal (MBM, plastic waste and sugarcane bagasse. The model was developed on the basis of energy and mass balance of the system and was validated against data from a reference cement plant. This study also investigated the effect of these alternative fuels on the quality of the clinker. The results indicated that up to a 4.4% reduction in CO2 emissions and up to a 6.4% reduction in thermal energy requirement could be achieved using these alternative fuels with 20% mix in coal. It was also found that the alternative fuels had minimum influence on the clinker quality except in the case of MSW. Overall, MBM was found to be a better option as it is capable on reducing energy requirement and CO2 emissions more than others. The outcomes of the study offer better understanding of the effects of solid alternative fuels to achieve higher energy performance and on mitigating pollutant emissions in cement industry.

INFLUENCE OF WINE ACID ON RHEOLOGICAL PROPERTIES OF WELL BORE CEMENT SLURRIES AND HARDENED CEMENT PROPERTIES

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

1989-12-01

Full Text Available Adaptation of commercial types of domestic cements for use in cementing the deep wells is a process by which Yugoslav oil industry tends to solve problems of completion of those wells independently. In order to design a domestic, cheep and effective retarder, tests of applicability of wine acid on cement slurries have been carried out. Besides examining the necessary wine acid content to achieve desirable Theological properties, the influence of this additive on properties of hardened cement samples has been tested too (the paper is published in Croatian.

Ceramic microspheres for cementing applications

NARCIS (Netherlands)

2011-01-01

A method and apparatus for manufacturing ceramic microspheres from industrial slag. The microspheres have a particle size of about 38 microns to about 150 microns. The microspheres are used to create a cement slurry having a density of at least about 11 lbs/g. The resultant cement slurry may then be

Ceramic microspheres for cementing applications

NARCIS (Netherlands)

2010-01-01

A method and apparatus for manufacturing ceramic microspheres from industrial slag. The microspheres have a particle size of about 38 microns to about 150 microns. The microspheres are used to create a cement slurry having a density of at least about 11 lbs/g. The resultant cement slurry may then be

Ceramic microspheres for cementing applications

NARCIS (Netherlands)

2012-01-01

A method and apparatus for manufacturing ceramic microspheres from industrial slag. The microspheres have a particle size of about 38 microns to about 150 microns. The microspheres are used to create a cement slurry having a density of at least about 11 lbs/g. The resultant cement slurry may then be

Fiscal 1999 technical survey report. Model project implementation feasibility study in China on effective utilization of cement waste heat; 1999 nendo Chugoku ni okeru cement hainetsu yuko riyo model jigyo jisshi kanosei chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

Although China ranks first in the world in the manufacture of cement, yet the energy consumption rate is high and there remains room for improvement. Effective utilization of energy at cement making plants will not only profit the industry but also contribute to the stabilization of energy supply for China. The model project on power generation using cement waste heat implemented at Ningguo Cement Plant was concluded successfully. For the purpose of enabling China to domestically manufacture the equipment, the installation of such equipment at Zhujiang Cement Plant and Liuzhou Cement Plant in Guangxi Zhuangzu Zizhiqu was assumed, and their locations and plant operating conditions were studied. In addition, surveys were conducted of manufacturers of important components of the power generation equipment such as boilers, steam turbines, generators, and breaker boards. Two manufacturers were visited for each of the components, and they were checked for records of manufacturing similar equipment, quality assurance and process management capabilities, and for ability to satisfy required specifications. Among the visited manufacturers were Nanjing Turbine and Electric Machinery Co., Jinan Power Equipment Factory, and Hangzhou Boiler Works. Based on the results of the surveys, it was concluded that the model project may be implemented. (NEDO)

CEMENT. "A Concrete Experience." A Curriculum Developed for the Cement Industry.

Science.gov (United States)

Taylor, Mary Lou

This instructor's guide contains 11 lesson plans for inplant classes on workplace skills for employees in a cement plant. The 11 units cover the following topics: goals; interpreting memoranda; applying a standard set of work procedures; qualities of a safe worker; accident prevention; insurance forms; vocabulary development; inventory control…

Investigating different factors influencing job satisfaction: A case study of cement industry

Directory of Open Access Journals (Sweden)

Mina Shirvani

2013-10-01

Full Text Available Job satisfaction plays an important role on increasing business productivity and efficiency. This paper presents an empirical investigation to study the relationship between job satisfaction and employees’ personal characteristics including gender, marital status, etc. The proposed study designs a questionnaire and distributes it among 244 out of 800 employees who worked for cement industry in Iran. The data are analyzed using different statistical tests such as t-student and analysis of variance. The results indicate that while there was not any meaningful relationship between gender and job satisfaction there was some meaningful relationship between marital status and job satisfaction.

Challenges of technical cooperation in the petroleum industry

International Nuclear Information System (INIS)

Al-Athel, S.A.

1992-01-01

The need and prospects for international technical cooperation in the petroleum industry are reviewed. Since it directly affects the survival of the inhabitants of the planet, environmental protection is a field that could enjoy maximum international cooperation; oil spills, product environmental hazards, waste minimization and disposal and oil field fires are the main areas identified. Technical cooperation in other areas of the industry, namely exploration, production, oil field development, refining and petrochemicals, may involve some controversy. Attention is drawn to the conflicting interests of multinational companies, who almost completely control the technology of these activities, and host developing countries. It is advocated that arrangements involving technology transfer should make provision for the growth of indigenous technology. (UK)

Is it cement to be? Downhole cement that uses zeolite additive may offer lightweight alternative

Energy Technology Data Exchange (ETDEWEB)

Mahoney, J.

2001-05-01

C2C Zeolite Corporation produces zeolites from a large deposit near Cache Creek, British Columbia, and processes them for use as an additive in downhole cement well casings. Early research indicates that zeolites can significantly improve the way downhole cement is made in the oil industry. Zeolites are made up mostly of silicates of aluminum and calcium. They have a great ability to absorb water, resulting in a lighter and more fluid cement than is currently available. C2C claims that zeolites will reduce cement weight, column pressure and operator costs. The cost benefits of using lighter cement downhole includes easier moving, processing and handling of the mix. Initial research suggests that zeolites might prove to be viable alternatives to other cement lighteners such as silica fumes or flyash. Zeolite-based cement also performed reasonably well in freeze-thaw tests and showed good adhesion and no evidence of shrinkage in downhole tests. 3 figs.

Challenges of the growing African cement market – environmental issues, regulative framework, and quality infrastructure requirements

Directory of Open Access Journals (Sweden)

Schmidt Wolfram

2018-01-01

Full Text Available The African cement, concrete and construction business is growing at rapid pace. The cement sales are expected to grow rapidly until 2050. The number of newly built cement plants increases dramatically and in addition more cements are being imported from outside the continent, e.g. from Turkey, Pakistan, Indonesia, and China, driven by overcapacities in the countries of origin. This causes a high number of potentials and challenges at the same time. Newly built cement plants can operate directly at best technological state of the art and thus incorporate more sustainable technologies as well as produce new and more sustainable products such as cements blended with sustainable supplementary cementitious materials such as calcined clays, and industrial or agricultural by products. At the same time the new variety of binding agent as well as the international imports, which are driven by price considerations, make the cement market prone to quality scatter. This puts pressure on the quality control regulations and institutions to ensure safety of construction, healthy application, and environmental safety for the population. The paper presents possible solutions to build up the rapidly increasing African cement production more sustainably than in the rest of the world as well as the related challenges and obstacles that need to be overcome. Based on experiences with a series of pan-African cement testing laboratory proficiency schemes conclusions are made on technical, regulative and political level.

Process development for utilizing asbestos cement waste in rotary kilns for the cement industry. Final report; Erarbeitung eines Verfahrens zur stofflichen Verwertung von zementgebundenen Asbestprodukten in Drehrohroefen fuer die Zementindustrie. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Schlegel, R.; Kieser, J.; Kraehner, A.

1999-11-01

The law for recycling and waste demands the utilization also for waste of asbestos cement (ac). The procedure of thermal utilization of ac in the flame of a rotary cement kiln was developed and patented by the research institute IBU-tec Weimar, Germany. The ac-material has to be pre-pulverized and grinded to a degree of fineness of R{sub 90}<15%. Considerations of safety engineering lead to the idea of common fine grinding of old oil (oo) and ac. This new procedure was searched in FuE-project in 1998/99 (financial support by BMBF). A mash of ac and oo was generated as a utilization product ready for firing which was injected into the flame of the rotary cement kiln. This particles of ac smelt to spherical shaped particles at a temperature above 1500 C. They were utilized by clinker formation. The material and gas stream leaving the kiln does not contain fibres of asbestos. This was demonstrated in a small equipment burning test. The industrial realization concerning cement plant Ruedersdorf, near Berlin, was searched, technologically described and safety engineeringly and financially assessed by a project study. Process-technical and financial advantages were seen for the dry fine grinding. The wet fine grinding with old oil could be used in cement plants using old oil as fuel. (orig.) [German] Das Kreislaufwirtschafts- und Abfallgesetz (1994) fordert u.a. die stoffliche Verwertung auch fuer Asbestzementabfaelle (AZ). Das vom Institut fuer Baustoff- und Umweltschutz-Technologie Weimar 1995 entwickelte und patentierte Verfahren zur thermischen Verwertung von AZ in der Flamme eines Zementdrehrohrofens erfuellt diese Forderung. Das AZ-Material muss vorzerkleinert und bis zur Rohmehlfeinheit (R{sub 90}<15%) feingemahlen werden. Sicherheitstechnische Ueberlegungen fuehrten zu der Idee, die Feinmahlung zusammen mit Altoel (AOe) zu erproben. Diese Verfahrensvariante wurde im Rahmen eines FuE-Projektes 1998/99 untersucht (finanzielle Foerderung durch das BMBF). Als

Customer satisfaction as a mediator between causes (trust and communication and the outcome (customer loyalty in business-to-business relationship marketing in the South African cement manufacturing industry

Directory of Open Access Journals (Sweden)

Phineas Mbango

2015-06-01

Full Text Available Customer loyalty has become more relevant in the cement industry since the unbundling of the cartel system in 1994, the entrance of new competitors into the market and the effect of globalization. This study’s literature review reveals that there is limited published research in the Cement Industry, particularly in South Africa, which deals with customer loyalty management. The major objective of the study was to test satisfaction as a mediator between causes and outcome, the causes being trust and communication and the outcome being customer loyalty. The methodological approach followed was a survey and quantitative in nature. Data were collected from 362 major business-to-business cement customers throughout South Africa’s nine provinces using the face-to-face interview technique with self-administered questionnaires. The data collected in the empirical study were analysed using the structural equations modelling (SEM. The results show that in order to maintain customer loyalty, a cement supplier has to focus on strategies to build relationships on the basis of creating customer satisfaction and/or exceeding customer needs and wants. They also need to invest in enhancing customer trust and communication. Another important finding is that trust and communication have no direct effect on loyalty. Customer satisfaction is therefore the most important mediator as it leads to customer loyalty. Customer loyalty is crucial for business success in terms of repeat purchase, referrals (word-of-mouth marketing, retention and long-term profitability. There exists evidence from literature of an outcry for a need for future studies to examine causes and outcomes of satisfaction to specific industries. This study contributes to theory and practice by closing that gap, by providing a framework of causes and outcomes of satisfaction specifically aimed at the cement industry. Another contribution of this study is its examination of the sequential logic of

Wide-scale utilization of MSWI fly ashes in cement production and its impact on average heavy metal contents in cements: The case of Austria.

Science.gov (United States)

Lederer, Jakob; Trinkel, Verena; Fellner, Johann

2017-02-01

A number of studies present the utilization of fly ashes from municipal solid waste incineration (MSWI) in cement production as a recycling alternative to landfilling. While there is a lot of research on the impact of MSWI fly ashes utilization in cement production on the quality of concrete or the leaching of heavy metals, only a few studies have determined the resulting heavy metal content in cements caused by this MSWI fly ashes utilization. Making use of the case of Austria, this study (1) determines the total content of selected heavy metals in cements currently produced in the country, (2) designs a scenario and calculates the resulting heavy metal contents in cements assuming that all MSWI fly ashes from Austrian grate incinerators were used as secondary raw materials for Portland cement clinker production and (3) evaluates the legal recyclability of demolished concretes produced from MSWI fly ash amended cements based on their total heavy metal contents. To do so, data from literature and statistics are combined in a material flow analysis model to calculate the average total contents of heavy metals in cements and in the resulting concretes according to the above scenario. The resulting heavy metal contents are then compared (i) to their respective limit values for cements as defined in a new technical guideline in Austria (BMLFUW, 2016), and (ii) to their respective limit values for recycling materials from demolished concrete. Results show that MSWI fly ashes utilization increases the raw material input in cement production by only +0.9%, but the total contents of Cd by +310%, and Hg, Pb, and Zn by +70% to +170%. However these and other heavy metal contents are still below their respective limit values for Austrian cements. The same legal conformity counts for recycling material derived from concretes produced from the MSWI fly ash cements. However, if the MSWI fly ash ratio in all raw materials used for cement production were increased from 0.9% to 22

75 FR 54969 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2010-09-09

... Hazardous Air Pollutants From the Portland Cement Manufacturing Industry and Standards of Performance for... Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing Industry and Standards of... (NESHAP) from the Portland Cement Manufacturing Industry and to the New Source Performance Standards (NSPS...

Incidence of cancer and mortality among employees in the asbestos cement industry in Denmark

DEFF Research Database (Denmark)

Raffn, E; Lynge, E; Juel, K

1989-01-01

In a cohort study of the incidence of cancer and mortality among 7996 men and 584 women employed in the Danish asbestos cement industry between 1928 and 1984 over 99% were traced. Chrysotile asbestos was the only fibre type used until 1946, when amosite and (in 1952) crocidolite were also...... introduced. Chrysotile constituted 89%, amosite 10%, and crocidolite 1% of the asbestos used. During the first 25 years of manufacture the exposure levels were high, especially in areas where the asbestos was handled dry. Measurements from 1948 indicate that the fibre levels may have ranged from 100 to 1600...... for men for non-malignant pulmonary diseases (O/E 1.63; 95% CI 1.33-1.98). Among the group of asbestos cement workers with first employment 1928-40 an excess risk of laryngeal cancer was found (O/E 5.50;95% CI 1.77-12.82). A total of 12 cases of pleural and one of peritoneal mesotheliomas was observed...

Maintenance Free and Sustainable High-Level Control in Cement and Mining Industry

DEFF Research Database (Denmark)

Hansen, Ole Fink

2009-01-01

High-level control systems have been utilized in the process industry for decades, and also in cement production their use is well established. In comparison to manual control their ability to increase production and quality of end product, while reducing energy consumption and emission, is well...... but nevertheless still require maintenance. For the 10% of the algorithm that is control related, the maintenance issue is to some extent addressed by research topics such as adaptive control, which aim at retuning the parameters of the algorithm to match the changing process. In this project however, it has been...... chosen to focus on the remaining 90% of the algorithm which still require manual modifications to cope with a changed process. Although this issue has gained limited attention from academia so far it is well recognized by the industry. In the process of maintaining an algorithm it has turned out...

Compressive Strength and Physical Properties Behavior of Cement Mortars with addition of Cement Klin Dust

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Auday A Mehatlaf

2017-12-01

Full Text Available Cement Klin Dust (CKD was the waste of almost cement industry factories, so that in this paper utilization of CKD as filler in cement and/or concrete was the main objective. CKD from the Karbala cement factory had been used and analysis to know the chemical composition of the oxides was done. In this paper cement mortars with different weight percentages of CKD (0,5,10,20,30,40 had been prepared. Physical properties such as density and porosity were done in different age curing (3, 7, 28 day. In addition, mechanical properties included the coefficient of thermal conductivity and compressive strength had also observed with different age (3,7, and 28 for all prepared specimens. From the obtained the experimental results and their discussion, it was clear that the addition (20% of CKD had the good results in cement mortars.  

77 FR 46371 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

Science.gov (United States)

2012-08-03

...-AQ93 National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing... Portland Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants,'' which was... Manufacturing Industry and Standards of Performance for Portland Cement Plants'' under Docket ID No. EPA-HQ-OAR...

MENINGKATKAN TECHNICAL SKILL SISWA SMK TEKNIK BANGUNAN MELALUI PELAKSANAAN PRAKTIK KERJA INDUSTRI

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Blima Oktaviastuti

2016-04-01

Full Text Available This paper aims to expose the study of: (1 technical skill; (2 the working practices of the industry (Prakerin; and (3 technical skill on implementation prakerin. Conclusions it can be concluded that, the real form of Prakerin is the implementation of the system of education in SMK is Double System Education (PSG. The program was drawn up jointly between prakerin school and industrial world in order to meet the needs of students. The party was active in the activities of prakerin include: (1 the implementing party as students practice; and (2 the industrial world and the teacher as the party that train students. The existence of activities expected prakerin can give students experience before entering the world of work. Through the activities, indirectly prakerin students have gained technical skill required as a provision for entering the workforce. Given the current state of infrastructure development is preferred, the demand for construction workers is the main one. Graduates of Vocational School building techniques is expected to have the technical skill to be able to compete with the foreign worker entering the era of the MEA as of now. Tulisan ini bertujuan untuk memaparkan kajian tentang: (1 technical skill; (2 Praktik Kerja Industri (Prakerin; dan (3 technical skill pada pelaksanaan prakerin. Kesimpulan yang dapat disimpulkan bahwa, prakerin merupakan wujud nyata dari pelaksanaan sistem pendidikan di SMK yaitu Pendidikan Sistem Ganda (PSG. Program prakerin disusun bersama antara sekolah dan dunia industri dalam rangka memenuhi kebutuhan siswa. Pihak yang aktif dalam kegiatan prakerin, meliputi (1 siswa sebagai pihak pelaksana praktik; serta (2 dunia industri dan guru sebagai pihak yang melatih siswa. Adanya kegiatan prakerin diharapkan dapat memberi pengalaman siswa sebelum memasuki dunia kerja. Melalui kegiatan prakerin, secara tidak langsung siswa telah mendapatkan technical skill yang dibutuhkan sebagai bekal memasuki dunia kerja

Causes and outcomes of customer satisfaction in business-to-business markets relationship marketing in the South African cement manufacturing industry

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Phineas Mbango

2015-10-01

Full Text Available Close relationships between cement manufacturers and their customers in business-to-business markets are becoming a necessity in today’s competitive markets. The literature search reveals that, three constructs of relationship marketing (trust, commitment and satisfaction are the most studied and well known. This study contributes to the body of knowledge by adding two constructs (supplier competencies and communication as vital causes to customer satisfaction and the outcome being customer loyalty and cooperation. The study produced a framework of dimensions of relationship marketing in the South African Cement Industry and its hoped will help marketing managers in the industry and related sectors in coming up with relationship marketing strategies that can go a long way in helping them retain, attract, satisfy, and achieve long-term profitable relationships for both the supplier and the customer. A judgemental sample of major cement customers (362 throughout South Africa’s nine provinces were contacted using face-to-face interview technique with self-administered questionnaires. The results support the conceptual model presented; supplier competencies, trust, commitment and communication have a positive association with satisfaction; and satisfaction, in turn, relates positively to all the two outcomes of cooperation and loyalty. It is recommended that a cement manufacturer must invest in strategies that enhance trust, communication, commitment and supplier competencies in order to satisfy its customers who will in turn contribute to customer cooperation and loyalty.

Using Scientific and Industrial Films in Teaching Technical Communication.

Science.gov (United States)

Veeder, Gerry

A film course especially designed for technical communication students can illustrate basic film concepts and techniques while showing how film effectively communicates ideas in an industrial and scientific communication system. After a basic introduction to film terms, the study of actual scientific and industrial films demonstrates the following…

Efficiency modeling of solidification/stabilization of multi-metal contaminated industrial soil using cement and additives

International Nuclear Information System (INIS)

Voglar, Grega E.; Lestan, Domen

2011-01-01

Highlights: → We assess the feasibility of using soil S/S for industrial land reclamation. → Retarders, accelerators, plasticizers were used in S/S cementitious formulation. → We proposed novel S/S efficiency model for multi-metal contaminated soils. - Abstract: In a laboratory study, formulations of 15% (w/w) of ordinary Portland cement (OPC), calcium aluminate cement (CAC) and pozzolanic cement (PC) and additives: plasticizers cementol delta ekstra (PCDE) and cementol antikorodin (PCA), polypropylene fibers (PPF), polyoxyethylene-sorbitan monooleate (Tween 80) and aqueous acrylic polymer dispersion (Akrimal) were used for solidification/stabilization (S/S) of soils from an industrial brownfield contaminated with up to 157, 32,175, 44,074, 7614, 253 and 7085 mg kg -1 of Cd, Pb, Zn, Cu, Ni and As, respectively. Soils formed solid monoliths with all cementitious formulations tested, with a maximum mechanical strength of 12 N mm -2 achieved after S/S with CAC + PCA. To assess the S/S efficiency of the used formulations for multi-element contaminated soils, we propose an empirical model in which data on equilibrium leaching of toxic elements into deionized water and TCLP (toxicity characteristic leaching procedure) solution and the mass transfer of elements from soil monoliths were weighed against the relative potential hazard of the particular toxic element. Based on the model calculation, the most efficient S/S formulation was CAC + Akrimal, which reduced soil leachability of Cd, Pb, Zn, Cu, Ni and As into deionized water below the limit of quantification and into TCLP solution by up to 55, 185, 8750, 214, 4.7 and 1.2-times, respectively; and the mass transfer of elements from soil monoliths by up to 740, 746, 104,000, 4.7, 343 and 181-times, respectively.

Efficiency modeling of solidification/stabilization of multi-metal contaminated industrial soil using cement and additives

Energy Technology Data Exchange (ETDEWEB)

Voglar, Grega E. [RDA - Regional Development Agency Celje, Kidriceva ulica 25, 3000 Celje (Slovenia); Lestan, Domen, E-mail: domen.lestan@bf.uni-lj.si [Agronomy Department, Centre for Soil and Environmental Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia)

2011-08-30

Highlights: {yields} We assess the feasibility of using soil S/S for industrial land reclamation. {yields} Retarders, accelerators, plasticizers were used in S/S cementitious formulation. {yields} We proposed novel S/S efficiency model for multi-metal contaminated soils. - Abstract: In a laboratory study, formulations of 15% (w/w) of ordinary Portland cement (OPC), calcium aluminate cement (CAC) and pozzolanic cement (PC) and additives: plasticizers cementol delta ekstra (PCDE) and cementol antikorodin (PCA), polypropylene fibers (PPF), polyoxyethylene-sorbitan monooleate (Tween 80) and aqueous acrylic polymer dispersion (Akrimal) were used for solidification/stabilization (S/S) of soils from an industrial brownfield contaminated with up to 157, 32,175, 44,074, 7614, 253 and 7085 mg kg{sup -1} of Cd, Pb, Zn, Cu, Ni and As, respectively. Soils formed solid monoliths with all cementitious formulations tested, with a maximum mechanical strength of 12 N mm{sup -2} achieved after S/S with CAC + PCA. To assess the S/S efficiency of the used formulations for multi-element contaminated soils, we propose an empirical model in which data on equilibrium leaching of toxic elements into deionized water and TCLP (toxicity characteristic leaching procedure) solution and the mass transfer of elements from soil monoliths were weighed against the relative potential hazard of the particular toxic element. Based on the model calculation, the most efficient S/S formulation was CAC + Akrimal, which reduced soil leachability of Cd, Pb, Zn, Cu, Ni and As into deionized water below the limit of quantification and into TCLP solution by up to 55, 185, 8750, 214, 4.7 and 1.2-times, respectively; and the mass transfer of elements from soil monoliths by up to 740, 746, 104,000, 4.7, 343 and 181-times, respectively.

Utilization of Palm Oil Clinker as Cement Replacement Material

Directory of Open Access Journals (Sweden)

Jegathish Kanadasan

2015-12-01

Full Text Available The utilization of waste materials from the palm oil industry provides immense benefit to various sectors of the construction industry. Palm oil clinker is a by-product from the processing stages of palm oil goods. Channelling this waste material into the building industry helps to promote sustainability besides overcoming waste disposal problems. Environmental pollution due to inappropriate waste management system can also be drastically reduced. In this study, cement was substituted with palm oil clinker powder as a binder material in self-compacting mortar. The fresh, hardened and microstructure properties were evaluated throughout this study. In addition, sustainability component analysis was also carried out to assess the environmental impact of introducing palm oil clinker powder as a replacement material for cement. It can be inferred that approximately 3.3% of cement production can be saved by substituting palm oil clinker powder with cement. Reducing the utilization of cement through a high substitution level of this waste material will also help to reduce carbon emissions by 52%. A cleaner environment free from pollutants can be created to ensure healthier living. Certain industries may benefit through the inclusion of this waste material as the cost and energy consumption of the product can be minimized.

Utilization of Palm Oil Clinker as Cement Replacement Material.

Science.gov (United States)

Kanadasan, Jegathish; Abdul Razak, Hashim

2015-12-16

The utilization of waste materials from the palm oil industry provides immense benefit to various sectors of the construction industry. Palm oil clinker is a by-product from the processing stages of palm oil goods. Channelling this waste material into the building industry helps to promote sustainability besides overcoming waste disposal problems. Environmental pollution due to inappropriate waste management system can also be drastically reduced. In this study, cement was substituted with palm oil clinker powder as a binder material in self-compacting mortar. The fresh, hardened and microstructure properties were evaluated throughout this study. In addition, sustainability component analysis was also carried out to assess the environmental impact of introducing palm oil clinker powder as a replacement material for cement. It can be inferred that approximately 3.3% of cement production can be saved by substituting palm oil clinker powder with cement. Reducing the utilization of cement through a high substitution level of this waste material will also help to reduce carbon emissions by 52%. A cleaner environment free from pollutants can be created to ensure healthier living. Certain industries may benefit through the inclusion of this waste material as the cost and energy consumption of the product can be minimized.

Technical roles and success of US federal laboratory-industry partnerships

OpenAIRE

Barry Bozeman; Dennis Wittmer

2001-01-01

Drawing from questionnaire-based data of 229 US federal laboratory-industry joint R&D projects, this research examines the composition of the technical interaction by character of the R&D performed to determine the impacts on effectiveness of the technical roles played by research partners. In addition to the particular technical roles, their number and diversity are examined, giving particular attention to the subset of projects in which the company played no technical role. Our findings sho...

Development of low radio-activated cement. Characteristics of cement and clinker that decreased liquid phase content

International Nuclear Information System (INIS)

Ichitsubo, Koki

2008-01-01

Low radio-activated cement was developed by decreasing the parent elements of radionuclides in the materials. The characteristics of products, decreasing method of Na, Eu and Co in cement, design, tests, evaluation, and analysis of low radio-activated cement clinker are reported. In order to decrease the content of Na, Eu and Co, the raw materials have to include natural materials such as limestone and silica stone. The production method is the same as white cement. The low radio-activated cement produced by rotary kiln showed 4.9% C 3 A, 1.1% C 4 AF, 26.9% C 3 S and 61.0% C 2 S, which values were standardized by the Japanese Industrial Standards (JIS) of low temperature Portland cement. Another product that decreased a little more liquid phase content showed 4.0% C 3 A, 1.0% C 4 AF, 32.3% C 3 S and 56.5% C 2 S, which was standardized by JIS of sulfate resisting Portland cement. In the case of decommissioning reactor constructed by the low radio-activated cement, the whole amount of waste cement will be no more than the clearance level. (S.Y.)

[Has application of the decree banning the use of cement with a high chromium VI content led to a reduction in occupational cement dermatitis in salaried workers in the construction industries?].

Science.gov (United States)

Halioua, Bruno; Bensefa-Colas, Lynda; Crepy, Marie-Noëlle; Bouquiaux, Barbara; Assier, Haudrey; Billon, Stéphane; Chosidow, Olivier

2013-03-01

Active employees in the construction industry are particularly exposed to occupational cement eczema (OCE) which affects the hands in 80 to 90% of cases. The importance of OCE in France and the impact of the application of decree n(o). 2005-577 on 26 May 2005 were estimated from data collected by the Occupational risks division of the French national health insurance fund for salaried workers (CNAMTS). This decree prohibits the placing on the market and use of cement (and preparations containing it) with a chromium VI content above 0.0002% in order to reduce its hazardousness. All cases of OCE reported to and recognized by the CNAMTS between 1 January 2004 and 31 December 2008 among construction workers were selected. The following parameters were noted in each case: age, gender, industrial sector concerned, local French National health insurance agency, causal agent and the number of working days lost. The incidence per 100,000 salaried workers could be determined from the total number of salaried workers followed up by occupational medicine as well as those working in the construction industry. For the five years studied, 3698 cases of occupational eczema (OE) were reported in construction workers and this was 17.1% of the total number of cases of OE for all salaried employees (n=12.689). Cement was the causal agent most frequently involved in the construction sector (57.8%, 2139/3698). The annual incidence of OCE decreased from 37.8 to 21.1 new cases per 100,000 employees in the construction industry per year between 2004 and 2008. The total number of days lost from work due to OCE decreased by 39% during the study period. This descriptive study highlights the importance and socio-economic impact of OCE in the construction industry. Application of decree n(o). 2005-577 on 26 May 2005 may explain a reduction in OCE. Copyright © 2012. Published by Elsevier Masson SAS.

Environmental impact of incineration of calorific industrial waste: rotary kiln vs. cement kiln.

Science.gov (United States)

Vermeulen, Isabel; Van Caneghem, Jo; Block, Chantal; Dewulf, Wim; Vandecasteele, Carlo

2012-10-01

Rotary kiln incinerators and cement kilns are two energy intensive processes, requiring high temperatures that can be obtained by the combustion of fossil fuel. In both processes, fossil fuel is often substituted by high or medium calorific waste to avoid resource depletion and to save costs. Two types of industrial calorific waste streams are considered: automotive shredder residue (ASR) and meat and bone meal (MBM). These waste streams are of current high interest: ASR must be diverted from landfill, while MBM can no longer be used for cattle feeding. The environmental impact of the incineration of these waste streams is assessed and compared for both a rotary kiln and a cement kiln. For this purpose, data from an extensive emission inventory is applied for assessing the environmental impact using two different modeling approaches: one focusing on the impact of the relevant flows to and from the process and its subsystems, the other describing the change of environmental impact in response to these physical flows. Both ways of assessing emphasize different aspects of the considered processes. Attention is paid to assumptions in the methodology that can influence the outcome and conclusions of the assessment. It is concluded that for the incineration of calorific wastes, rotary kilns are generally preferred. Nevertheless, cement kilns show opportunities in improving their environmental impact when substituting their currently used fuels by more clean calorific waste streams, if this improvement is not at the expense of the actual environmental impact. Copyright © 2012 Elsevier Ltd. All rights reserved.

QUANTIFICATION OF THE DECISIONS OF CONTROL AND AUDIT IN INVENTORY MANAGEMENT IN CEMENT INDUSTRY ENTERPRISES

OpenAIRE

Sylwia £êgowik-Œwi¹cik

2011-01-01

Inventory management in enterprises of cement industry necessitates the assessment of the level of risk which is generated by production inventory. The processes of control and auditing allow for planning, monitoring and organization of inventory management in the analysed business entities. This paper is aimed at presentation of the phase of preparation of audit activities in the area of inventory and verification of model solutions for the processes of control and audit in terms of inventor...

Stabilization techniques for reactive aggregate in soil-cement base course : technical summary.

Science.gov (United States)

2003-01-01

The objectives of this research are 1) to identify the mineralogical properties of soil-cement bases which have heaved or can potentially heave, 2) to simulate expansion of cement-stabilized soil in the laboratory, 3) to correlate expansion with the ...

Characterization of sugar cane bagasse ash as supplementary material for Portland cement

Directory of Open Access Journals (Sweden)

Janneth Torres Agredo

2014-01-01

Full Text Available Sugar Cane Bagasse is a by-product of the sugar agroindustry; it is partly used as fuel. However, bagasse ash (SCBA is considered waste, which creates a disposal problem. Furthermore, if sugar cane bagasse is burned under controlled conditions, the SCBA can be potentially reused. This paper considers the technical viability of using SCBA as a partial replacement for cement. Two samples of SCBA from a Colombian sugar industry were characterized. The chemical composition of the samples shows high percentages of silica, 76.3% and 63.2%. The mineralogical and morphological characteristics of the waste were determined by X-ray diffraction patterns (XRD, thermal analysis (TG/DTA and scanning electron microscopy (SEM. The pozzolanic activity of SCBA was evaluated using the Frattini test and the strength activity index test (SAI. The ASTM C618 defines an SAI of at least 75% as a requirement for classifying material as a pozzolan. This condition was achieved in the experiments performed. The results indicate that SCBA produced in the manufacture of commercial cements can be recycled for use as pozzolanic material. This supplementary material can partially replace cement and therefore reduce CO2 emissions.

Influence of Environmentally Friendly and High-Efficiency Composite Additives on Pulverized Coal Combustion in Cement Industry

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Zhiyong Wang

2016-01-01

Full Text Available 4 kinds of chemical reagents and 3 kinds of industrial wastes were selected as burning additives for 2 kinds of coals in cement industry. The work focused on the replacement of partial chemical reagents by industrial wastes, which not only reduced the cost and took full advantage of industrial wastes, but also guaranteed the high combustion efficiency and removed the NOX and SO2 simultaneously. The experiments were carried out in DTF. The combustion residues were analyzed by SEM and XRD. The results showed that the burnout rate was increased after adding the additives; meanwhile, the NOX and SO2 release concentration were reduced, but the degree of action varied for different additives and coals. The substitute of chemical reagents by industrial wastes was very effective; overall, the cold-rolled iron oxide worked better than others; the particles surface was tougher and the peaks of crystalline phase were lower than raw coal, which indicated that the additives played good roles in combustion process.

Accelerated weathering of limestone for CO2 mitigation opportunities for the stone and cement industries

Science.gov (United States)

Langer, W.H.; Juan, C.A.S.; Rau, G.H.; Caldeira, K.

2009-01-01

Large amounts of limestone fines coproduced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO 2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacturing. AWL reactants are readily available, inexpensive, and environmentally benign. Waste CO 2 is hydrated with water to produce carbonic acid, which then reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities within about 10 km of the coastline. The majority of U.S. coastal power generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufactures, and research scientists.

Health hazards of cement dust

International Nuclear Information System (INIS)

Meo, Sultan A.

2004-01-01

ven in the 21st century, millions of people are working daily in a dusty environment. They are exposed to different types of health hazards such as fume, gases and dust, which are risk factors in developing occupational disease. Cement industry is involved in the development of structure of this advanced and modern world but generates dust during its production. Cement dust causes lung function impairment, chronic obstructive lung disease, restrictive lung disease, pneumoconiosis and carcinoma of the lungs, stomach and colon. Other studies have shown that cement dust may enter into the systemic circulation and thereby reach the essentially all the organs of body and affects the different tissues including heart, liver, spleen, bone, muscles and hairs and ultimately affecting their micro-structure and physiological performance. Most of the studies have been previously attempted to evaluate the effects of cement dust exposure on the basis of spirometry or radiology, or both. However, collective effort describing the general effects of cement dust on different organ and systems in humans or animals, or both has not been published. Therefore, the aim of this review is to gather the potential toxic effects of cement dust and to minimize the health risks in cement mill workers by providing them with information regarding the hazards of cement dust. (author)

Crop residues as a potential renewable energy source for Malawi's cement industry

DEFF Research Database (Denmark)

Gondwe, Kenneth J.; Chiotha, Sosten S.; Mkandawire, Theresa

2017-01-01

that the projected total energy demands in 2020, 2025 and 2030 were approximately 177 810 TJ, 184 210 TJ and 194 096 TJ respectively. The highest supply potentials were found to be in the central and southern regions of Malawi, coinciding with the locations of the two clinker plants. Crop residues could meet 45......-57% of the national total energy demand. The demand from the cement industry is only 0.8% of the estimated biomass energy potential. At an annual production of 600 000 t of clinker and 20% biomass co-firing with coal, 18 562 t of coal consumption would be avoided and 46 128 t of carbon dioxide emission reduction...

The Effects of the Asian Crisis To Turkish Manufacturing Industry : The Case of Textile, Food and Cement Industries = Asya Krizinin Türk İmalat Sanayisine Etkileri: Tekstil, Gıda ve Çimento Sanayileri Örneği

Directory of Open Access Journals (Sweden)

Abdülmecit KARATAŞ

2001-06-01

Full Text Available This paper hypothesizes that Asian crisis has severely affected the financial dimensions of the Turkish industries. The analysis of the financial data for 70 companies from textile, food and cement industries provides evidence to partially support this hypothesis. By principal components analysis we identified five statistical factors that is meaningful and economically significant to represent main financial dimensions contained in twenty-one financial variables of the sample firms. The discriminant analyses based on the identification of the discrimination between financial dimensions of the sample firms for pre- and post-crisis years identified that profitability margins of the export-oriented Turkish textile industry significantly decreased in post-crisis years. No statistically significant changes in financial dimensions are detected for food and cement industries in post-crisis years.

Customer satisfaction as a mediator between causes (trust and communication) and the outcome (customer loyalty) in business-to-business relationship marketing in the South African cement manufacturing industry

OpenAIRE

Phineas Mbango; Maxwell A. Phiri

2015-01-01

Customer loyalty has become more relevant in the cement industry since the unbundling of the cartel system in 1994, the entrance of new competitors into the market and the effect of globalization. This study’s literature review reveals that there is limited published research in the Cement Industry, particularly in South Africa, which deals with customer loyalty management. The major objective of the study was to test satisfaction as a mediator between causes and outcome, the causes being tru...

Emerging Energy-efficiency and CO{sub 2} Emission-reduction Technologies for Cement and Concrete Production

Energy Technology Data Exchange (ETDEWEB)

Hasanbeigi, Ali; Price, Lynn; Lin, Elina

2012-04-06

Globally, the cement industry accounts for approximately 5 percent of current anthropogenic carbon dioxide (CO{sub 2}) emissions. World cement demand and production are increasing significantly, leading to an increase in this industry's absolute energy use and CO{sub 2} emissions. Development of new energy-efficiency and CO{sub 2} emission-reduction technologies and their deployment in the market will be key for the cement industry's mid- and long-term climate change mitigation strategies. This report is an initial effort to compile available information on process description, energy savings, environmental and other benefits, costs, commercialization status, and references for emerging technologies to reduce the cement industry's energy use and CO{sub 2} emissions. Although studies from around the world identify a variety of sector-specific and cross-cutting energy-efficiency technologies for the cement industry that have already been commercialized, information is scarce and/or scattered regarding emerging or advanced energy-efficiency and low-carbon technologies that are not yet commercialized. This report consolidates available information on nineteen emerging technologies for the cement industry, with the goal of providing engineers, researchers, investors, cement companies, policy makers, and other interested parties with easy access to a well-structured database of information on these technologies.

Alternative Fuels in Cement Production

DEFF Research Database (Denmark)

Larsen, Morten Boberg

The substitution of alternative for fossil fuels in cement production has increased significantly in the last decade. Of these new alternative fuels, solid state fuels presently account for the largest part, and in particular, meat and bone meal, plastics and tyre derived fuels (TDF) accounted...... for the most significant alternative fuel energy contributors in the German cement industry. Solid alternative fuels are typically high in volatile content and they may differ significantly in physical and chemical properties compared to traditional solid fossil fuels. From the process point of view......, considering a modern kiln system for cement production, the use of alternative fuels mainly influences 1) kiln process stability (may accelerate build up of blockages preventing gas and/or solids flow), 2) cement clinker quality, 3) emissions, and 4) decreased production capacity. Kiln process stability...

Micrometer-scale 3-D shape characterization of eight cements: Particle shape and cement chemistry, and the effect of particle shape on laser diffraction particle size measurement

International Nuclear Information System (INIS)

Erdogan, S.T.; Nie, X.; Stutzman, P.E.; Garboczi, E.J.

2010-01-01

Eight different portland cements were imaged on a synchrotron beam line at Brookhaven National Laboratory using X-ray microcomputed tomography at a voxel size of about 1 μm per cubic voxel edge. The particles ranged in size roughly between 10 μm and 100 μm. The shape and size of individual particles were computationally analyzed using spherical harmonic analysis. The particle shape difference between cements was small but significant, as judged by several different quantitative shape measures, including the particle length, width, and thickness distributions. It was found that the average shape of cement particles was closely correlated with the volume fraction of C 3 S (alite) and C 2 S (belite) making up the cement powder. It is shown that the non-spherical particle shape of the cements strongly influence laser diffraction results, at least in the sieve size range of 20 μm to 38 μm. Since laser diffraction particle size measurement is being increasingly used by the cement industry, while cement chemistry is always a main factor in cement production, these results could have important implications for how this kind of particle size measurement should be understood and used in the cement industry.

Incorporating environmental co-benefits into climate policies: A regional study of the cement industry in China

International Nuclear Information System (INIS)

Yang, Xi; Teng, Fei; Wang, Gehua

2013-01-01

Highlights: • First study on the co-benefits of mitigation measures in the cement sector in China. • We evaluate the economic value of damage of various pollutants at local level. • We evaluate 18 energy-saving technologies for 31 provinces in cement sector. • The value for the co-benefits ranged from 3 $/t CO 2 to 39 $/t CO 2 . • The large spatial variations may justify stringent targets for richer provinces. - Abstract: We analyzed the impacts of incorporating local air quality improvement and environmental co-benefits into the climate policy and mitigation technology assessment of the cement sector in China. Local air quality can benefit from reducing greenhouse gas emissions, which consequently lowers abatement costs and strengthens the cost-effectiveness of mitigation technologies. We used a simplified approach to estimate environmental damage factors due to air pollution at the sub-national level in China. The calculated economic costs of environmental damage due to PM 10 , NO x , and SO 2 were 7,714 $/t, 1,006 $/t, and 902 $/t, respectively. These values vary among the provinces. We found that most energy-saving technologies in the cement industry will create significant co-benefits, ranging from 3 $/t CO 2 to 39 $/t CO 2 at the national level; however, a tradeoff for carbon capture and storage (CCS) and energy-saving technologies also resulted with increased electricity consumption. Large spatial variations of co-benefits can be gained at the sub-national level and justify the enactment of more stringent climate policies in the wealthier regions in China

The Office of Industrial Technologies technical reports

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

The US Department of Energy's Office of Industrial Technologies (OIT) conducts R D activities which focus on the objectives of improving energy efficiency and providing for fuel flexibility within US industry in the area of industrial energy conservation. The Office also conducts programs to reduce waste generation, increase recycling efforts, and improve the use of wastes as process feedstocks. An active program of technology transfer and education supports these activities and encourages adoption of new technologies. To accomplish these objectives OIT cooperates with the private sector to identify its technological needs and to share R D efforts. R D is conducted to the point that a new technology is shown to work and that it can be transferred to the private sector end-users. This bibliography contains information on all scientific and technical reports sponsored by the DOE Industrial Energy Conservation Program during the years 1988--1990.

Alkali-Activated Mortars for Sustainable Building Solutions: Effect of Binder Composition on Technical Performance

Directory of Open Access Journals (Sweden)

Agnese Attanasio

2018-02-01

Full Text Available There is a growing interest in the construction sector in the use of sustainable binders as an alternative to ordinary Portland cement, the production of which is highly impacting on the environment, due to high carbon dioxide emissions and energy consumption. Alkali-activated binders, especially those resulting from low-cost industrial by-products, such as coal fly ash or metallurgical slag, represent a sustainable option for cement replacement, though their use is more challenging, due to some technological issues related to workability or curing conditions. This paper presents sustainable alkali-activated mortars cured in room conditions and based on metakaolin, fly ash, and furnace slag (both by-products resulting from local sources and relevant blends, aiming at their real scale application in the building sector. The effect of binder composition—gradually adjusted taking into consideration technical and environmental aspects (use of industrial by-products in place of natural materials in the view of resources saving—on the performance (workability, compressive strength of different mortar formulations, is discussed in detail. Some guidelines for the design of cement-free binders are given, taking into consideration the effect of each investigated alumino-silicate component. The technical feasibility to produce the mortars with standard procedures and equipment, the curing in room conditions, the promising results achieved in terms of workability and mechanical performance (from 20.0 MPa up to 52.0 MPa, confirm the potential of such materials for practical applications (masonry mortars of class M20 and Md. The cement-free binders resulting from this study can be used as reference for the development of mortars and concrete formulations for sustainable building materials production.

Production of portland cement using Moroccan oil shale and comparative study between conventional cement plant and cement plant using oil shale

International Nuclear Information System (INIS)

Doumbouya, M.; Kacemi, K.E.; Kitane, S.

2012-01-01

Like the use of coal ash from power plants as an addition to cement, oil shale are used for cement production on an industrial scale in Estonia, China, USA and Germany. Oil shale can be utilized in manufacturing the cement. In addition to the utilization of these by-products after combustion, it can also reduce the required temperature for the clinkering reactions during the production of Portland clinker. We performed a study on the Moroccan oil shale to maximize the use of oil shale ash in the manufacturing of Portland cement. We found that Moroccan oil shale ash can be used up to 30% with 70% Portland clinker without altering its principle properties. The corresponding temperature required to generate the required liquid for the clinkering reactions as well as the essential ingredients for clinker was found to be around 850 to 1000 deg. C. The operating temperatures for this optimized blend ratio were found to 1000 deg. C. The resulting Portland clinker from this ratio will need further testing in accordance with international standards for Portland cement to examine properties like strength and setting time. (author)

Refuse derived fuel (RDF) plasma torch gasification as a feasible route to produce low environmental impact syngas for the cement industry.

Science.gov (United States)

López-Sabirón, Ana M; Fleiger, Kristina; Schäfer, Stefan; Antoñanzas, Javier; Irazustabarrena, Ane; Aranda-Usón, Alfonso; Ferreira, Germán A

2015-08-01

Plasma torch gasification (PTG) is currently researched as a technology for solid waste recovery. However, scientific studies based on evaluating its environmental implications considering the life cycle assessment (LCA) methodology are lacking. Therefore, this work is focused on comparing the environmental effect of the emissions of syngas combustion produced by refuse derived fuel (RDF) and PTG as alternative fuels, with that related to fossil fuel combustion in the cement industry. To obtain real data, a semi-industrial scale pilot plant was used to perform experimental trials on RDF-PTG.The results highlight that PTG for waste to energy recovery in the cement industry is environmentally feasible considering its current state of development. A reduction in every impact category was found when a total or partial substitution of alternative fuel for conventional fuel in the calciner firing (60 % of total thermal energy input) was performed. Furthermore, the results revealed that electrical energy consumption in PTG is also an important parameter from the LCA approach. © The Author(s) 2015.

Improvement of geotechnical properties of sabkha soil utilizing cement kiln dust

Directory of Open Access Journals (Sweden)

Abdullah A. Al-Homidy

2017-08-01

Full Text Available Improvement of properties of weak soils in terms of strength, durability and cost is the key from engineering point of view. The weak soils could be stabilized using mechanical and/or chemical methods. Agents added during chemical stabilization could improve the engineering properties of treated soils. Stabilizers utilized have to satisfy noticeable performance, durability, low price, and can be easily implemented. Since cement kiln dust (CKD is industrial by-product, it would be a noble task if this waste material could be utilized for stabilization of sabkha soil. This study investigates the feasibility of utilizing CKD for improving the properties of sabkha soil. Soil samples are prepared with 2% cement and 10%, 20% or 30% CKD and are tested to determine their unconfined compressive strength (UCS, soaked California bearing ratio (CBR and durability. Mechanism of stabilization is studied utilizing advanced techniques, such as the scanning electron microscope (SEM, energy dispersive X-ray analysis (EDX, backscattered electron image (BEI and X-ray diffraction analysis (XRD. It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid pavements. The incorporation of CKD leads to technical and economic benefits.

Feasibility of backfilling mines using cement kiln dust, fly ash, and cement blends

OpenAIRE

Beltagui, Hoda; Sonebi, Mohammed; Maguire, K.; Taylor, Susan

2018-01-01

Cement kiln dust (CKD) is an industrial by-product of the cement manufacturing process, the composition of which can vary widely. Recent years of using alternative fuels have resulted in higher chloride and alkali contents within CKDs; as such, this limits the applications in which CKDs can be utilised. Using a CKD containing a high free lime content of 29.5%, it is shown that this CKD is capable of activating pulverized fuel ash (PFA) due to its high alkalinity, which can be utilised in low ...

Use of the “red gypsum” industrial waste as substitute of natural gypsum for commercial cements manufacturing

Directory of Open Access Journals (Sweden)

Gázquez, M. J.

2012-06-01

Full Text Available The main objective of this research has been the valorisation of a waste from the TiO2 production process (sulphate method, called red gypsum, in the production of cements. This waste is mainly formed by di-hydrate calcium sulphate and iron hydroxides. To cover this objective it has been necessary to perform the physico-chemical characterisation of the red gypsum as well as the main components in the production of cements and of the new cements generated. Moreover, for the red gypsum, has been analyzed its radioactive content because it is generated in a NORM (Naturally Occurring Radioactive Materials industry. Finally, the most important properties of the obtained cements with different proportions of red gypsum in their composition have been studied by comparing them with the standard ones obtained in a Portland cement. Lastly, we have demonstrated that the new cements fulfil all the quality tests imposed by the European legislation.

El objetivo de esta investigación ha sido analizar la valorización de un residuo generado en el proceso de producción de dióxido de titanio (vía sulfato, denominado yeso rojo, en la producción de cementos. Dicho residuo está compuesto fundamentalmente por sulfato de calcio di-hidratado e hidróxidos de hierro. Para ello, ha sido necesaria la caracterización físico-química del yeso rojo, así como la de los otros componentes fundamentales en la fabricación de cementos y de los cementos generados con el mencionado residuo. Además, en el caso del yeso rojo, se ha analizado su contenido radiactivo al generarse éste en una industria NORM (Natural Occurring Radioactive Materials. Posteriormente, se han estudiado las propiedades más importantes de los cementos producidos con diferentes porcentajes de yeso rojo añadido, comparando estas mezclas con las propiedades de un cemento Portland comercial, comprobándose que se cumplen todas las normas Europeas de calidad exigibles.

Technical property and application of industrial computed tomography

International Nuclear Information System (INIS)

Sun Lingxia; Ye Yunchang

2006-01-01

The main technical property of industrial computed tomography (ICT) and its application in non-destructive testing (NDT) were described. And some examples of ICT applications in such fields as defects detection, welding quality, density uniformity, structure analysis and making-up quality were given. (authors)

Integrated energy optimisation for the cement industry: A case study perspective

International Nuclear Information System (INIS)

Swanepoel, Jan Adriaan; Mathews, Edward Henry; Vosloo, Jan; Liebenberg, Leon

2014-01-01

Highlights: • Integration of all energy-intensive components of a cement plant production process in a simulation package. • Uniquely, the simulation model incorporates constraints such as maintenance, production and dynamic energy costs. • The system was implemented on four different cement plants and a total energy cost saving of 7.1% was achieved. - Abstract: Energy costs play a major role in the cement production process. As much as 60% of total cost is allocated to energy and 18% to the consumption of electrical energy. Historically, energy cost savings were achieved by large infrastructure upgrades. These upgrades are often costly and lead to interruptions in production. In this paper the operation of all the energy intensive components of the cement production process are identified, modelled, integrated and optimised for minimum operational costs while meeting production targets. This integrated approach allows for simulation of the collective effect of individual production components. The system incorporates constraints such as maintenance, production and dynamic energy costs. No published research could be found where these constraints are incorporated into a single operational solution. The system was implemented on four cement plants and a total energy cost saving of 7% was achieved. This highlights the practical significance of an integrated approach to energy cost savings

The regulation of hazardous air pollutants under the Clean Air Act Amendments of 1990: Effects on the Portland cement industry

International Nuclear Information System (INIS)

Mikols, E.H.; Gill, A.S.; Dougherty, A.

1996-01-01

Title III of the 1990 Clean Air Act Amendments (CAAA) addresses the control of hazardous air pollutants (HAPs) from major sources of air pollution in the US. In the CAAA, Congress defined 189 compounds as hazardous air pollutants in need of additional control by the Environmental Protection Agency (EPA). Congress directed EPA to identify the major source categories which emit HAPs and to prepare regulations that would reduce and control future HAP emissions. This paper outlines the activities undertaken by EPA to regulate HAP emissions from Portland cement plants and the program developed by the Portland cement manufacturing industry to cope with Title III

Obtaining a sulfoaluminate belite cement by industrial waste

Directory of Open Access Journals (Sweden)

Elkhadiri, L.

2003-06-01

Full Text Available Sulfoaluminate belite clinkers by burning raw at moderate temperatures near 1250 °C were synthesized. The used mixtures were made by calcium carbonate blended to two industrial wastes: low calcium fly ash and phosphogypsum. The clinkers were characterised by X-Ray Diffraction (XRD, Infrared Spectroscopy (FTIR and free lime. The hydraulic behaviour of the obtained cements, by adequate clinkers with 7% of added gypsum, was followed by XRD, scaning electronic microscopy (SEM, FTIR and NMR.

Los clínkeres belíticos de sulfoaluminatos se obtienen por cocción de crudos a temperaturas moderadas, hacia 1.250 ºC. Esos crudos se componen de carbonato de calcio mezclados con dos subproductos industriales: cenizas volantes pobres en óxido de calcio y fosfoyeso. Los clínkeres obtenidos se caracterizaron a través de Difracción de Rayos X (DRX, Espectroscopia Infrarroja por Transformada de Fourier (FTIR y por la determinación de CaO libre. El comportamiento hidráulico de los cementos elaborados de los clínkeres con el 7% de yeso se estudió por DRX, Microscopía Electrónica de Barrido (SEM, FTIR y Resonancia Magnética Nuclear (RMN

Cement solidification of spent ion exchange resins produced by the nuclear industry

International Nuclear Information System (INIS)

Jaouen, C.; Vigreux, B.

1988-01-01

Cement solidification technology has been applied to spent ion exchange resins for many years in countries throughout the world (at reactors, research centers and spent fuel reprocessing plants). Changing specifications for storage of radioactive waste have, however, confronted the operators of such facilities with a number of problems. Problems related both to the cement solidification process (water/cement/resin interactions and chemical interactions) and to its utilization (mixing, process control, variable feed composition, etc.) have often led waste producers to prefer other, polymer-based processes, which are very expensive and virtually incompatible with water. This paper discusses research on cement solidification of ion exchange resins since 1983 and the development of application technologies adapted to nuclear service conditions and stringent finished product quality requirements

Study of incorporation of casting wastes in soil-cement blocks

International Nuclear Information System (INIS)

Folmann, R.; Malkowski, W.; Valentina, L.V.D.; Folgureras, M.V.

2011-01-01

Soil-cement bricks are an ecological alternative to conventional ones because they don't need to be burned to gain strength. This study examines the technical possibility of reuse of foundry sand as fine aggregate in soil-cement. The raw materials were characterized by X-ray diffraction, thermal analysis and particle size. The foundry sand wastes were mixed at different levels to soil and cement. Compaction tests were performed to define the mixtures at optimum moisture content corresponding to the maximum density. Isothermal Conduction Calorimeter was performed to study the influence of waste in the cement hydration reaction. The results indicate that the addition of foundry sand waste decreases the optimum moisture content and increases the maximum density without significantly affecting the cement set. (author)

Limestone calcined clay cement as a low-carbon solution to meet expanding cement demand in emerging economies

Directory of Open Access Journals (Sweden)

Yudiesky Cancio Díaz

Full Text Available This paper aims at assessing the return on investment and carbon mitigation potentials of five investment alternatives for the Cuban cement industry in a long-term horizon appraisal (15 years. Anticipated growing demand for cement, constrained supply and an urgent need for optimisation of limited capital while preserving the environment, are background facts leading to the present study. This research explores the beneficial contribution of a new available technology, LC3 cement, resulting from the combination of clinker, calcined clay and limestone, with a capacity of replacing up to 50% of clinker in cement. Global Warming Potential (GWP is calculated with Life Cycle Assessment method and the economic investment's payback is assessed through Return on Capital Employed (ROCE approach. Main outcomes show that projected demand could be satisfied either by adding new cement plants—at a high environmental impact and unprofitable performance— or by introducing LC3 strategy. The latter choice allows boosting both the return on investment and the production capacity while reducing greenhouse gas (GHG emissions up to 20–23% compared to business-as-usual practice. Overall profitability for the industry is estimated to overcome BAU scenario by 8–10% points by 2025, if LC3 were adopted. Increasing the production of conventional blended cements instead brings only marginal economic benefits without supporting the needed increase in production capacity. The conducted study also shows that, in spite of the extra capital cost required for the calcination of kaolinite clay, LC3 drops production costs in the range of 15–25% compared to conventional solutions. Keywords: Cement, Alternative, ROCE, CO2, LCA, Investment

Development of rock segment for reduction of amount of cement use

International Nuclear Information System (INIS)

Tada, Hiroyuki; Kumasaka, Hiroo; Saito, Akira; Nakaya, Atsushi; Ishii, Takashi; Sanada, Masanori; Noguchi, Akira; Kishi, Hirokazu; Nakama, Shigeo; Fujita, Tomoo

2013-01-01

The authors have been developing methods for constructing tunnels using the minimum quantities of cement-type support materials in high-level radioactive waste disposal facilities and advancing research and development about the technical formation of rock segment using low alkali mortar. In this study, the mechanical characteristic values concerning the rock segment and backfill materials were examined. The stability analysis of drift supported by the rock segment and backfilling with gravel were performed. Technical formation and effectiveness of the support planned for further reduction in cement influence was confirmed from the study result. (author)

Industrial coal survey

Energy Technology Data Exchange (ETDEWEB)

1992-05-25

UK industrial coal sales were down 400,000t to 7.1mt in 1991. This was largely due to fall in cement purchases as the construction industry was badly hit in the recession. Increased competition from petroleum coke also had an effect. A brief roundup is presented of sales to the UK's major coal buyers: Alcan, ICI, Blue Circle, Castle Cement, Rugby Cement, British Steel, UK Paper, Courtaulds, Unilever, AHS Emstar, Tate Lyle, and British Sugar. 1 tab.

Leaching of heavy metals from cementitious composites made of new ternary cements

Science.gov (United States)

Kuterasińska-Warwas, Justyna; Król, Anna

2017-10-01

The paper presents a comparison of research methods concerning the leaching of harmful substances (selected heavy metal cations ie. Pb, Cu, Zn and Cr) and their degree of immobilization in cement matrices. The new types of ternary cements were used in the study, where a large proportion of cement clinker was replaced by other non-clinker components - industrial wastes, ie. siliceous fly ash from power industry and granulated blast furnace slag from the iron and steel industry. In studied cementitious binders also ground limestone was used, which is a widely available raw material. The aim of research is determining the suitability of new cements for neutralizing harmful substances in the obtained matrices. The application of two research methods in accordance with EN 12457-4 and NEN 7275 intends to reflection of changing environmental conditions whom composite materials may actually undergo during their exploitation or storing on landfills. The results show that cements with high addition of non-clinker components are suitable for stabilization of toxic substances and the obtained cement matrices retain a high degree of immobilization of heavy metals at the level of 99%.

Palisades technical specification conversion from custom to new industry standard

International Nuclear Information System (INIS)

Foley, D.J.; Young, B.

1990-01-01

Consumers Power Company's (CPCo) Palisades plant is in the process of converting from custom technical specifications to the new industry standard, Restructured Standard Technical Specifications (RSTS). Custom technical specifications were the precursor to standard technical specifications, being issued to plants built prior to 1972. In May 1989, each of the four light water reactor owners' groups completed topical reports presenting their version of Restructured Standard Technical Specifications to the Nuclear Regulatory Commission (NRC). After approval of the owners' groups versions of the RSTs by the NRC, individual operating reactors will begin to make the conversion to the RSTS. Each owners' group has designated a lead plant, which will be the first of that vendor type to convert. All of the lead plants currently operate under standard technical specifications. The content of the RSTS was determined by comparing the standard technical specifications with selection criteria specified in the Commissions Interim Policy Statement

The effect of fly ash and coconut fibre ash as cement replacement materials on cement paste strength

Science.gov (United States)

Bayuaji, R.; Kurniawan, R. W.; Yasin, A. K.; Fatoni, H. AT; Lutfi, F. M. A.

2016-04-01

Concrete is the backbone material in the construction field. The main concept of the concrete material is composed of a binder and filler. Cement, concrete main binder highlighted by environmentalists as one of the industry are not environmentally friendly because of the burning of cement raw materials in the kiln requires energy up to a temperature of 1450° C and the output air waste CO2. On the other hand, the compound content of cement that can be utilized in innovation is Calcium Hydroxide (CaOH), this compound will react with pozzolan material and produces additional strength and durability of concrete, Calcium Silicate Hydrates (CSH). The objective of this research is to explore coconut fibers ash and fly ash. This material was used as cement replacement materials on cement paste. Experimental method was used in this study. SNI-03-1974-1990 is standard used to clarify the compressive strength of cement paste at the age of 7 days. The result of this study that the optimum composition of coconut fiber ash and fly ash to substitute 30% of cement with 25% and 5% for coconut fibers ash and fly ash with similar strength if to be compared normal cement paste.

CEMENT SLURRIES FOR GEOTHERMAL WELLS CEMENTING

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

1994-12-01

Full Text Available During a well cementing special place belongs to the cement slurry design. To ensure the best quality of cementing, a thorough understanding of well parameters is essential, as well as behaviour of cement slurry (especially at high temperatures and application of proven cementing techniques. Many cement jobs fail because of bad job planning. Well cementing without regarding what should be accomplished, can lead to well problems (channels in the cement, unwanted water, gas or fluid production, pipe corrosion and expensive well repairs. Cementing temperature conditions are important because bot-tomhole circulating temperatures affect slurry thickening time, arheology, set time and compressive strength development. Knowing the actual temperature which cement encounters during placement allows the selection of proper cementing materials for a specific application. Slurry design is affected by well depth, bottom hole circulating temperature and static temperature, type or drilling fluid, slurry density, pumping time, quality of mix water, fluid loss control, flow regime, settling and free water, quality of cement, dry or liquid additives, strength development, and quality of the lab cement testing and equipment. Most Portland cements and Class J cement have shown suitable performances in geot-hermal wells. Cement system designs for geothermal wells differ from those for conventional high temperature oil and gas wells in the exclusive use of silica flour instead of silica sand, and the avoidance of fly ash as an extender. In this paper, Portland cement behaviour at high temperatures is described. Cement slurry and set cement properties are also described. Published in literature, the composition of cement slurries which were tested in geothermal conditions and which obtained required compressive strength and water permeability are listed. As a case of our practice geothermal wells Velika Ciglena-1 and Velika Ciglena-la are described.

Technical Writing in the Computer Industry: Job Opportunities for PH.D.'s.

Science.gov (United States)

Turnbull, Andrew D.

1981-01-01

Answers questions about the field of technical writing, especially in the computer industry. Explains what "software" and "software documentation" are, what the "software documentation specialist" (technical writer) does, and how to prepare for such a job. (FL)

Apparatus for manufacturing ceramics microspheres for cementing applications

NARCIS (Netherlands)

2012-01-01

A method and apparatus for manufacturing ceramic microspheres from industrial slag. The micro spheres have a particle size of about 38 microns to about 150 microns. The microspheres are used to create a cement slurry having a density of at least about Illbs/g. The resultant cement slurry may then be

Centralized cement solidification technique for low-level radioactive wastes

International Nuclear Information System (INIS)

Matsuda, Masami; Nishi, Takashi; Izumida, Tatsuo; Tsuchiya, Hiroyuki.

1996-01-01

A centralized cement solidification system has been developed to enable a single facility to solidify such low-level radioactive wastes as liquid waste, spent ion exchange resin, incineration ash, and miscellaneous solid wastes. Since the system uses newly developed high-performance cement, waste loading is raised and deterioration of waste forms after land burial prevented. This paper describes the centralized cement solidification system and the features of the high-performance cement. Results of full-scale pilot plant tests are also shown from the viewpoint of industrial applicability. (author)

Methods and Production of Cementation Materials for Immobilisation into Waste Form. Research of Cementation Processes for Specific Liquid Radioactive Waste Streams of Radiochemical Plants

International Nuclear Information System (INIS)

Sukhanov, L.P.

2013-01-01

In the near future Russian Federation is planning to use industrial cementation facilities at two radiochemical combines - PA 'Mayak' and Mountain Chemical Combine. Scope of the research within the IAEA CRP contact No. 14176 included the development of cementation processes for specfic liquid radioactive waste streams that are present in these enterprisers. The research on cementation of liquid waste from spent nuclear fuel reprocessing at PA 'Mayak' allowed obtaining experimental data characterizing the technological process and basic characteristics of the produced cement compounds (e.g. mechanical strength, water resistance, frost resistance, flowability, etc.) immobilizing different streams of waste (e.g. hydrated-salt sludges, filter material pulps, mixture of hydrated salt slurries and filter material pulps, tritium liquid waste). Determined optimum technological parameters will allow industrial scale production of cement compound with required quality and higher flowability that is necessary for providing uniform filling of compartments of storage facilities at these sites. The research has been also carried out for the development of cementation technology for immobilization of pulps from storage tanks of Mountain Chemical Combine radiochemical plant. Cementation of such pulps is a difficult technological task because pulps are of complex chemical composition (e.g. hydroxides of manganese, iron, nickel, etc., as well as silicon oxide) and a relatively high activity. The research of cementation process selection for these pulps included studies of the impact of sorbing additive type and content on cement compounds leachability, flowability, impact of cement compound age to its mechanical strength, heat generation of cement compounds and others. The research results obtained allowed testing of cementation facility with a pulse type mixer on the full-scale. Use of such mixer for pulp cementation makes possible to prepare a homogeneous cement compound with the

Thermodynamic and exergoeconomic analysis of a cement plant: Part I – Methodology

International Nuclear Information System (INIS)

Atmaca, Adem; Yumrutaş, Recep

2014-01-01

Highlights: • Energy, exergy and exergoeconomic analysis of a complete cement plant have been investigated. • The first and second law efficiencies based on the energy and exergy analysis are defined for the entire cement plant. • The specific energy consumption of the whole sections of the cement plant have been analyzed. • The specific manufacturing costs of farine, clinker and cement have been determined by the cost analysis. - Abstract: The energy, exergy and exergoeconomic analysis of a cement factory has been studied within two parts. This paper is the first part of the study which includes the thermodynamic and exergoeconomic methodology and formulations developed for such a comprehensive and detailed analysis. The second part of this study is about the application of the developed formulation which considers an actual cement plant located in Gaziantep, Turkey. The energy consumption by the cement industry is about 5% of the total global industrial energy consumption. It is also one of the world’s largest industrial sources of CO 2 emissions. In this paper, a cement plant is considered with all main manufacturing units. Mass, energy, and exergy balances are applied to each system. The first and second law efficiencies based on the energy and exergy analysis and performance assessment parameters are defined for the entire cement plant. The formulations for the cost of products, and cost formation and allocation within the system are developed based on exergoeconomic analysis. In order to obtain the optimal marketing price of cement and to decrease specific energy consumption of the whole plant, the cost analysis formulated here have substantial importance

Total Factor Productivity Growth, Technical Progress & Efficiency Change in Vietnam Coal Industry - Nonparametric Approach

Science.gov (United States)

Phuong, Vu Hung

2018-03-01

This research applies Data Envelopment Analysis (DEA) approach to analyze Total Factor Productivity (TFP) and efficiency changes in Vietnam coal mining industry from 2007 to 2013. The TFP of Vietnam coal mining companies decreased due to slow technological progress and unimproved efficiency. The decadence of technical efficiency in many enterprises proved that the coal mining industry has a large potential to increase productivity through technical efficiency improvement. Enhancing human resource training, technology and research & development investment could help the industry to improve efficiency and productivity in Vietnam coal mining industry.

Optimizing the hydraulic program of cementing casing strings

Energy Technology Data Exchange (ETDEWEB)

Novakovic, M

1984-01-01

A technique is described for calculating the optimal parameters of the flow of plugging mud which takes into consideration the geometry of the annular space and the rheological characteristics of the muds. The optimization algorithm was illustrated by a block diagram. Examples are given for practical application of the optimization programs in production conditions. It is stressed that optimizing the hydraulic cementing program is effective if other technical-technological problems in cementing casing strings have been resolved.

The trilogy nuclear technology-quality-reliability in nuclear energy: the interface technical regulation/industrial norm in the nuclear industry

International Nuclear Information System (INIS)

Costa, Jose Ribeiro da

1995-01-01

In this paper, it is tried to find out a compatibility among Regulations (mandatory) documents governing Quality Assurance Requirements for the Nuclear Industry (like IAEA/50-C-QA, IAEA/50-SG-QA1, IAEA/50-SG-QA7, and others), with similar documents prescribing same requirements for COnventional Industry (like ISO/900 Series), using the technical support of the prescriptions contained in the IAEA/TR-328 documents. Harmonization and compatibility of these documents is a great deal for Industries engaged -directly or indirectly - in the Nuclear Technology, taking into account that such compatibility can avoid troubles for already ISO/9000 Series Certified Industries in the fulfillment of its contract requirements in the nuclear field. Its also represents in that field a symbiosis between Technical Regulations (mandatory) and Voluntary Standards (Industrial, Consensual Standards). (author). 7 refs., 1 fig., 1 tab

The polymer cement of sulfur as an alternative for the recycling of phosphogypsum. Corrosion testing of cements enriched with phosphogypsum

International Nuclear Information System (INIS)

Gasco, C.; Lopez, F. A.; Navarro, N.; Sanchez, M.; Sanz, B.; Ballesteros, O.; Higueras, E.; Roman, C. P.

2011-01-01

The possibility of the use of cement for the recycling of materials is seen today as sustainable solution of the fertilizer industry for production of matches (NORM). In this paper presents some results of corrosion tests performed on these cements modified using buffer solutions of different pH. The analytical determinations in these matrices are new challenges. (Author)

Coal as a source of energy to alleviate the crisis facing the cement industry

Energy Technology Data Exchange (ETDEWEB)

Reinert, N

1979-01-01

After recalling the importance of coal in the cement industry up until the end of the 1950s, and the regeneration of interest in this fuel, the author presents some views on the stocking of coal, on its preparation and on its application for firing. The advantages of linear stocking and of de-stocking by the 'front slice' method to ensure good homogenization are described. The precautions to be taken during the fine-grinding process and the transport of the pulverized coal in order to prevent coal-dust explosions are discussed. The main firing systems (direct, semi-direct and indirect) are discussed and their respective advantages and drawbacks examined. (In French)

Efficiency modeling of solidification/stabilization of multi-metal contaminated industrial soil using cement and additives.

Science.gov (United States)

Voglar, Grega E; Leštan, Domen

2011-08-30

In a laboratory study, formulations of 15% (w/w) of ordinary Portland cement (OPC), calcium aluminate cement (CAC) and pozzolanic cement (PC) and additives: plasticizers cementol delta ekstra (PCDE) and cementol antikorodin (PCA), polypropylene fibers (PPF), polyoxyethylene-sorbitan monooleate (Tween 80) and aqueous acrylic polymer dispersion (Akrimal) were used for solidification/stabilization (S/S) of soils from an industrial brownfield contaminated with up to 157, 32,175, 44,074, 7614, 253 and 7085mg kg(-1) of Cd, Pb, Zn, Cu, Ni and As, respectively. Soils formed solid monoliths with all cementitious formulations tested, with a maximum mechanical strength of 12N mm(-2) achieved after S/S with CAC+PCA. To assess the S/S efficiency of the used formulations for multi-element contaminated soils, we propose an empirical model in which data on equilibrium leaching of toxic elements into deionized water and TCLP (toxicity characteristic leaching procedure) solution and the mass transfer of elements from soil monoliths were weighed against the relative potential hazard of the particular toxic element. Based on the model calculation, the most efficient S/S formulation was CAC+Akrimal, which reduced soil leachability of Cd, Pb, Zn, Cu, Ni and As into deionized water below the limit of quantification and into TCLP solution by up to 55, 185, 8750, 214, 4.7 and 1.2-times, respectively; and the mass transfer of elements from soil monoliths by up to 740, 746, 104,000, 4.7, 343 and 181-times, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

Design and application of environmentally effective concrete with usage of chrysotile-cement waste

OpenAIRE

Egorova Lada; Semenov Vyacheslav; Pligina Anna; Askhadullin Aizat

2016-01-01

Construction is resource-demanding industry, characterized by a large volume of waste. Particularly chrysotile cement waste obtained both in production and in dismantling over age chrysotile-cement products: corrugated asbestos boards and flat sheets, chrysotile-cement tubes. We propose to use dry chrysotile-cement waste as recycled aggregate for concrete. Based on developed compositions and identified properties of heavy concrete with chrysotile-cement waste introduce this technology to the ...

Modeling energy efficiency to improve air quality and health effects of China’s cement industry

International Nuclear Information System (INIS)

Zhang, Shaohui; Worrell, Ernst; Crijns-Graus, Wina; Krol, Maarten; Bruine, Marco de; Geng, Guangpo; Wagner, Fabian; Cofala, Janusz

2016-01-01

Highlights: • An integrated model was used to model the co-benefits for China’s cement industry. • PM_2_._5 would decrease by 2–4% by 2030 through improved energy efficiency. • 10,000 premature deaths would be avoided per year relative to the baseline scenario. • Total benefits are about two times higher than the energy efficiency costs. - Abstract: Actions to reduce the combustion of fossil fuels often decrease GHG emissions as well as air pollutants and bring multiple benefits for improvement of energy efficiency, climate change, and air quality associated with human health benefits. The China’s cement industry is the second largest energy consumer and key emitter of CO_2 and air pollutants, which accounts for 7% of China’s total energy consumption, 15% of CO_2, and 14% of PM_2_._5, respectively. In this study, a state-of-the art modeling framework is developed that comprises a number of different methods and tools within the same platform (i.e. provincial energy conservation supply curves, the Greenhouse Gases and Air Pollution Interactions and Synergies, ArcGIS, the global chemistry Transport Model, version 5, and Health Impact Assessment) to assess the potential for energy savings and emission mitigation of CO_2 and PM_2_._5, as well as the health impacts of pollution arising from China’s cement industry. The results show significant heterogeneity across provinces in terms of the potential for PM_2_._5 emission reduction and PM_2_._5 concentration, as well as health impacts caused by PM_2_._5. Implementation of selected energy efficiency measures would decrease total PM_2_._5 emissions by 2% (range: 1–4%) in 2020 and 4% (range: 2–8%) by 2030, compared to the baseline scenario. The reduction potential of provincial annual PM_2_._5 concentrations range from 0.03% to 2.21% by 2030 respectively, when compared to the baseline scenario. 10,000 premature deaths are avoided by 2020 and 2030 respectively relative to baseline scenario. The

Cement and concrete options paper

International Nuclear Information System (INIS)

1999-10-01

Greenhouse gas emissions associated with the production of concrete are projected to increase from 10.5 million tonnes in 1990 to almost 14 million tonnes in 2010. Over half of this amount will be non-energy related emissions of carbon dioxide resulting from the conversion of limestone to lime. According to this report by industry experts, the industry has an excellent record of improving energy efficiency and there are few easy gains remaining. Nevertheless, improvements in energy efficiency and fuel use, increased use of concrete where it can be shown to result in net reduction of GHG emissions, and partial replacement of cement by supplementary cementitious materials that involve no additional generation of GHGs, could yield an approximate reduction in carbon dioxide emissions of nearly seven million tons in 2010. The industry proposes three measures to realise these benefits: (1) encouraging replacement of fossil fuels by otherwise waste material, (2) encouraging increased use of concrete in constructing houses and roads, and (3) encouraging increased use of supplementary cementing materials. The industry is opposed to carbon or energy taxes that increase the cost of doing business, on the grounds that such taxes would adversely affect the industry's competitive position internationally. tabs

Random ionic mobility on blended cements exposed to aggressive environments

Energy Technology Data Exchange (ETDEWEB)

Garcia, Rosario, E-mail: rosario.garcia@uam.es [Departamento de Geologia y Geoquimica, Facultad de Ciencias, Universidad Autonoma, 28049 Madrid (Spain); Rubio, Virginia [Departamento de Geografia, Facultad de Filosofia y Letras, Universidad Autonoma, 28049 Madrid (Spain); Vegas, Inigo [Labein-Tecnalia, 48160 Derio, Vizcaya (Spain); Frias, Moises [Instituto Eduardo Torroja, CSIC, c/ Serrano Galvache, 4, 28033 Madrid (Spain)

2009-09-15

It is known that the partial replacement of cement by pozzolanic admixtures generally leads to modifications in the diffusion rates of harmful ions. Recent research has centred on obtaining new pozzolanic materials from industrial waste and industrial by-products and on the way that such products can influence the performance of blended cements. This paper reports the behaviour of cements blended with calcined paper sludge (CPS) admixtures under exposure to two different field conditions: sea water and cyclic changes in temperature and humidity. Cement mortars were prepared with 0% and 10% paper sludge calcined at 700 deg. C. The penetration of ions within the microstructure of cement matrices was studied using X-ray diffraction (XRD) and scanning electron microscopy equipped with an energy dispersive X-ray analyser (SEM/EDX) analytical techniques. The results show that ionic mobility varies substantially according to the type of exposure and the presence of the calcined paper sludge. The incorporation of 10% CPS is shown to assist the retention and diffusion of the ions.

Random ionic mobility on blended cements exposed to aggressive environments

International Nuclear Information System (INIS)

Garcia, Rosario; Rubio, Virginia; Vegas, Inigo; Frias, Moises

2009-01-01

It is known that the partial replacement of cement by pozzolanic admixtures generally leads to modifications in the diffusion rates of harmful ions. Recent research has centred on obtaining new pozzolanic materials from industrial waste and industrial by-products and on the way that such products can influence the performance of blended cements. This paper reports the behaviour of cements blended with calcined paper sludge (CPS) admixtures under exposure to two different field conditions: sea water and cyclic changes in temperature and humidity. Cement mortars were prepared with 0% and 10% paper sludge calcined at 700 deg. C. The penetration of ions within the microstructure of cement matrices was studied using X-ray diffraction (XRD) and scanning electron microscopy equipped with an energy dispersive X-ray analyser (SEM/EDX) analytical techniques. The results show that ionic mobility varies substantially according to the type of exposure and the presence of the calcined paper sludge. The incorporation of 10% CPS is shown to assist the retention and diffusion of the ions.

HYDRATION AND PROPERTIES OF BLENDED CEMENT SYSTEMS INCORPORATING INDUSTRIAL WASTES

Directory of Open Access Journals (Sweden)

Heikal M.

2013-06-01

Full Text Available This paper aims to study the characteristics of ternary blended system, namely granulated blast-furnace slag (WCS, from iron steel company and Homra (GCB from Misr Brick (Helwan, Egypt and silica fume (SF at 30 mass % pozzolanas and 70 mass % OPC. The required water of standard consistency and setting times were measured as well as physico-chemical and mechanical characteristics of the hardened cement pastes were investigated. Some selected cement pastes were tested by TGA, DTA and FT-IR techniques to investigate the variation of hydrated products of blended cements. The pozzolanic activity of SF is higher than GCB and WCS. The higher activity of SF is mainly due to its higher surface area than the other two pozzolanic materials. On the other side, GCB is more pozzolanic than WCS due to GCB containing crystalline silica quartz in addition to an amorphous phase. The silica quartz acts as nucleating agents which accelerate the rate of hydration in addition to its amorphous phase, which can react with liberating Ca(OH2 forming additional hydration products.

Industrial Wastes as Auxiliary Additives to Cement/Lime Stabilization of Soils

OpenAIRE

James, Jijo; Pandian, P. Kasinatha

2016-01-01

Chemical stabilization involves the use of chemical agents for initiating reactions within the soil for modification of its geotechnical properties. Cement and lime stabilization have been the most common stabilization methods adopted for soil treatment. Cement stabilization results in good compressive strengths and is preferred for cohesionless to moderately cohesive soil but loses effectiveness when the soil is highly plastic. Lime stabilization is the most preferred method for plastic clay...

Investigating the Influence of Waste Basalt Powder on Selected Properties of Cement Paste and Mortar

Science.gov (United States)

Dobiszewska, Magdalena; Beycioğlu, Ahmet

2017-10-01

Concrete is the most widely used man-made construction material in civil engineering applications. The consumption of cement and thus concrete, increases day by day along with the growth of urbanization and industrialization and due to new developments in construction technologies, population growing, increasing of living standard. Concrete production consumes much energy and large amounts of natural resources. It causes environmental, energy and economic losses. The most important material in concrete production is cement. Cement industry contributes to production of about 7% of all CO2 generated in the world. Every ton of cement production releases nearly one ton of CO2 to atmosphere. Thus the concrete and cement industry changes the environment appearance and influences it very much. Therefore, it has become very important for construction industry to focus on minimizing the environmental impact, reducing energy consumption and limiting CO2 emission. The need to meet these challenges has spurred an interest in the development of a blended Portland cement in which the amount of clinker is reduced and partially replaced with mineral additives - supplementary cementitious materials (SCMs). Many researchers have studied the possibility of using another mineral powder in mortar and concrete production. The addition of marble dust, basalt powder, granite or limestone powder positively affects some properties of cement mortar and concrete. This paper presents an experimental study on the properties of cement paste and mortar containing basalt powder. The basalt powder is a waste emerged from the preparation of aggregate used in asphalt mixture production. Previous studies have shown that analysed waste used as a fine aggregate replacement, has a beneficial effect on some properties of mortar and concrete, i.e. compressive strength, flexural strength and freeze resistance also. The present study shows the results of the research concerning the modification of cement

Nanoparticles usage tendencies in cementing systems for hydrocarbon wells

NARCIS (Netherlands)

Balza, A.; Perera, Y.; Brito, J.; Hurtado, A.; Quercia Bianchi, G.; Corona, O.; Colina, A.; Blanco, A.; Palomo, A.; Zaragoza, A.; Lopez, J.C.

2011-01-01

In oil and gas wells construction, one of the most critical processes is oil well cementing, whose function is to provide a zonal isolation between the pipe and sedimentary formation. For these reasons, one of the needs in the oil industry, specifically in cementing wells area, is the use of

Energy efficiency improvement potentials for the cement industry in Ethiopia

International Nuclear Information System (INIS)

Tesema, Gudise; Worrell, Ernst

2015-01-01

The cement sector is one of the fast growing economic sectors in Ethiopia. In 2010, it consumed 7 PJ of primary energy. We evaluate the potential for energy savings and CO_2 emission reductions. We start by benchmarking the energy performance of 8 operating plants in 2010, and 12 plants under construction. The benchmarking shows that the energy intensity of local cement facilities is high, when compared to the international best practice, indicating a significant potential for energy efficiency improvement. The average electricity intensity and fuel intensity of the operating plants is 34% and 36% higher. For plants under construction, electricity use is 36% and fuel use 27% higher. We identified 26 energy efficiency measures. By constructing energy conservation supply curves, the energy-efficiency improvement potential is assessed. For the 8 operating plants in 2010, the cost-effective energy savings equal 11 GWh electricity and 1.2 PJ fuel, resulting in 0.1 Mt CO_2 emissions reduction. For the 20 cement plants expected to be in operation by 2020, the cost-effective energy saving potentials is 159 GWh for electricity and 7.2 PJ for fuel, reducing CO_2 emissions by about 0.6 Mt. We discuss key barriers and recommendations to realize energy savings. - Highlights: • The cement sector in Ethiopia is growing rapidly, using mainly imported fuels. • Benchmarking demonstrates a significant potential for energy efficiency improvement. • A large part of the energy efficiency potential can be achieved cost-effectively. • Ethiopia should ban the construction of obsolete vertical shaft kilns.

A feasible process for simultaneous removal of CO2, SO2 and NOx in the cement industry by NH3 scrubbing

International Nuclear Information System (INIS)

Dong, Ruifeng; Lu, Hongfang; Yu, Yunsong; Zhang, Zaoxiao

2012-01-01

Highlights: ► Simultaneous removal of CO 2 , SO 2 and NO x is realized by NH 3 scrubbing with NaClO 2 . ► The crystallization process of NH 4 HCO 3 is employed instead of CO 2 regeneration. ► Energy consumption reduces hugely while CO 2 removal rate remains higher than 90%. ► Exergy calculation reveals that a higher thermodynamic perfection degree is achieved. -- Abstract: With the rapid economic and industrial development, the concentration of carbon dioxide in the atmosphere is increasing enormously, which has greatly affected the global climate and human living environment. At present, a lot of technologies have been applied to CO 2 removal in fossil fuel-fired power plants, which are one of the main CO 2 emission sources. But few researches have been done in the cement industry, which is the third largest CO 2 emission source. There is no mature technology of CO 2 removal in cement industry mentioned before. This paper proposes a feasible process for simultaneous removal of CO 2 , SO 2 and NO x in the cement industry by NH 3 scrubbing. As there is no ready steam source for the regeneration of CO 2 -rich loading solvent after absorption, a process with the final product of ammonium bicarbonate is developed. With the oxidative additive of NaClO 2 added in the aqueous ammonium absorbent, the simultaneous removal of CO 2 , SO 2 and NO x is feasible by NH 3 scrubbing. The products of the process are mainly ammonium bicarbonate, ammonium sulfate and ammonium nitrate, which are all good fertilizers for crops and plants. The crystallization of NH 4 HCO 3 is easier for storage and transportation than that for liquid carbon dioxide, which becomes more stable when dicyandiamide (DCD) is added. The thermodynamic analysis proves that the proposed process has the advantages of energy conservation and high thermodynamic perfection degree compared with the traditional ones.

Basalt waste added to Portland cement

Directory of Open Access Journals (Sweden)

Thiago Melanda Mendes

2016-08-01

Full Text Available Portland cement is widely used as a building material and more than 4.3 billion tons were produced in 2014, with increasing environmental impacts by this industry, mainly through CO2 emissions and consumption of non-removable raw materials. Several by-products have been used as raw materials or fuels to reduce environmental impacts. Basaltic waste collected by filters was employed as a mineral mixture to Portland cement and two fractions were tested. The compression strength of mortars was measured after 7 days and Scanning Electron Microscopy (SEM and Electron Diffraction Scattering (EDS were carried out on Portland cement paste with the basaltic residue. Gains in compression strength were observed for mixtures containing 2.5 wt.% of basaltic residue. Hydration products observed on surface of basaltic particles show the nucleation effect of mineral mixtures. Clinker substitution by mineral mixtures reduces CO2 emission per ton of Portland cement.

A Thermoelectric Waste-Heat-Recovery System for Portland Cement Rotary Kilns

Science.gov (United States)

Luo, Qi; Li, Peng; Cai, Lanlan; Zhou, Pingwang; Tang, Di; Zhai, Pengcheng; Zhang, Qingjie

2015-06-01

Portland cement is produced by one of the most energy-intensive industrial processes. Energy consumption in the manufacture of Portland cement is approximately 110-120 kWh ton-1. The cement rotary kiln is the crucial equipment used for cement production. Approximately 10-15% of the energy consumed in production of the cement clinker is directly dissipated into the atmosphere through the external surface of the rotary kiln. Innovative technology for energy conservation is urgently needed by the cement industry. In this paper we propose a novel thermoelectric waste-heat-recovery system to reduce heat losses from cement rotary kilns. This system is configured as an array of thermoelectric generation units arranged longitudinally on a secondary shell coaxial with the rotary kiln. A mathematical model was developed for estimation of the performance of waste heat recovery. Discussions mainly focus on electricity generation and energy saving, taking a Φ4.8 × 72 m cement rotary kiln as an example. Results show that the Bi2Te3-PbTe hybrid thermoelectric waste-heat-recovery system can generate approximately 211 kW electrical power while saving 3283 kW energy. Compared with the kiln without the thermoelectric recovery system, the kiln with the system can recover more than 32.85% of the energy that used to be lost as waste heat through the kiln surface.

Cementation of the solid radioactive waste with polymer-cement solutions using the method of impregnation

International Nuclear Information System (INIS)

Gorbunova, O.

2015-01-01

Cementation of solid radioactive waste (SRW), i.e. inclusion of solid radioactive waste into cement matrix without cavities - is one of the main technological processes used for conditioning low and intermediate level radioactive waste. At FSUE 'Radon' the industrialized method of impregnation has been developed and since 2003 has been using for cementation of solid radioactive waste. The technology is that the polymer-cement solution, having high penetrating properties, is supplied under pressure through a tube to the bottom of the container in which solid radioactive waste has preliminarily been placed. The polymer-cement solution is evenly moving upwards through the channels between the particles of solid radioactive waste, fills the voids in the bulk volume of the waste and hardens, forming a cement compound, the amount of which is equal to the original volume. The aim of the investigation was a selection of a cement solution suitable for SRW impregnation (including fine particles) without solution depletion and bottom layers stuffing. It has been chosen a polymer: PHMG (polyhexamethylene-guanidine), which is a stabilizing and water-retaining component of the cement solution. The experiments confirm that the polymer increases the permeability of the cement solution by a 2-2.5 factor, the viscosity by a 1.2 factor, the stability of the consistency by a 1.5-1.7 factor, and extends the operating range of the W/C ratio to 0.5-1.1. So it is possible to penetrate a volume of SRW bigger by a 1.5-2.0 factor. It has been proved, that PHMG polymer increases strength and frost-resistance of the final compounds by a 1.8-2.7 factor, and contributes to fast strength development at the beginning of hardening and it decreases Cs-137 leashing rate by a 1.5-2 factor

Environmental Assessment of Different Cement Manufacturing ...

Science.gov (United States)

Due to its high environmental impact and energy intensive production, the cement industry needs to adopt more energy efficient technologies to reduce its demand for fossil fuels and impact on the environment. Bearing in mind that cement is the most widely used material for housing and modern infrastructure, the aim of this paper is to analyse the Emergy and Ecological Footprint of different cement manufacturing processes for a particular cement plant. There are several mitigation measures that can be incorporated in the cement manufacturing process to reduce the demand for fossil fuels and consequently reduce the CO2 emissions. The mitigation measures considered in this paper were the use of alternative fuels and a more energy efficient kiln process. In order to estimate the sustainability effect of the aforementioned measures, Emergy and Ecological Footprint were calculated for four different scenarios. The results show that Emergy, due to the high input mass of raw material needed for clinker production, stays at about the same level. However, for the Ecological Footprint, the results show that by combining the use of alternative fuels together with a more energy efficient kiln process, the environmental impact of the cement manufacturing process can be lowered. The research paper presents an analysis of the sustainability of cement production , a major contributor to carbon emissions, with respect to using alternative fuels and a more efficient kiln. It show

Environmental, Human Health and Socio-Economic Effects of Cement Powders: The Multicriteria Analysis as Decisional Methodology.

Science.gov (United States)

Moretti, Laura; Di Mascio, Paola; Bellagamba, Simona

2017-06-16

The attention to sustainability-related issues has grown fast in recent decades. The experience gained with these themes reveals the importance of considering this topic in the construction industry, which represents an important sector throughout the world. This work consists on conducting a multicriteria analysis of four cement powders, with the objective of calculating and analysing the environmental, human health and socio-economic effects of their production processes. The economic, technical, environmental and safety performances of the examined powders result from official, both internal and public, documents prepared by the producers. The Analytic Hierarchy Process permitted to consider several indicators (i.e., environmental, human health related and socio-economic parameters) and to conduct comprehensive and unbiased analyses which gave the best, most sustainable cement powder. As assumed in this study, the contribution of each considered parameter to the overall sustainability has a different incidence, therefore the procedure could be used to support on-going sustainability efforts under different conditions. The results also prove that it is not appropriate to regard only one parameter to identify the 'best' cement powder, but several impact categories should be considered and analysed if there is an interest for pursuing different, often conflicting interests.

The role of technical museums in the regeneration of industrial functionally: Restructured regions Romania

Directory of Open Access Journals (Sweden)

Merciu Cristina

2012-01-01

Full Text Available The main purpose of the study is to depict the evolution of technical museums across Romania, high-lighting a new trend - visible in the past few years - towards preservation of industrial heritage assets in areas that have undergone functional reorganization. This trend is the result of the country's adaptation to the new socio-economic conditions, but also an accession into the stage of cultural and touristic capitalization on industrial heritage assets, acting as a support-activity in boosting the economy of dis advantaged industrial areas. The second purpose of the study consists of elaborating a critical analysis of technical museums from Romania in order to identify the characteristics to use to increase their cultural role. Also, the analysis is focused on the premise to make technical museums stand out as tourist attraction hubs and to preview their role in the redevelopment of industrial areas in decline, banking on a positive economic and socio-cultural impact.

Effects of Coal Gangue on Cement Grouting Material Properties

Science.gov (United States)

Liu, J. Y.; Chen, H. X.

2018-05-01

The coal gangue is one of the most abundant industrial solid wastes and pollute source of air and water. The use of coal gangue in the production of cement grouting material comforms to the basic state policy of environment protection and the circular using of natural resources. Through coal gangue processing experiment, coal gangue cement grouting materials making test, properties detection of properties and theoretical analysis, the paper studied the effects of coal gangue on the properties of cement grouting materials. It is found that at the range of 600 to 700 °C, the fluidity and the compressive and flexural strengths of the cement grouting materials increase with the rising up of the calcination temperatures of coal gangue. The optimum calcination temperature is around 700 °C. The part substitution of cement by the calcined coal gangue in the cement grouting material will improve the mechanical properties of the cement grouting material, even thought it will decrease its fluidity. The best substitution amount of cement by coal gangue is about 30%. The fluidity and the long term strength of the ordinary silicate cement grouting material is obviously higher than that of the sulphoaluminate cement one as well as that of the silicate-sulphoaluminate complex cement one.

Technical diagnosis of industrial plants with radioisotopes

International Nuclear Information System (INIS)

Hartmann, G.

1984-01-01

A survey is given of the application of radioisotopes in technical diagnosis of industrial plants. Proceeding from the economic importance and the state of the art of radioisotope applications, the principles of tracer techniques are outlined including topical examples of application such as passage of coal through a steam generator, wear in impact crashing of coal, wear and corrosion in pipelines, testing the effective cross section of pipes, and investigations of microstructures. Limits and restrictions of applications are briefly discussed

Contact dermatitis in cement workers in Isfahan

Directory of Open Access Journals (Sweden)

Iraji Fariba

2006-01-01

Full Text Available BACKGROUND: Due to recent industrialization and inadequately protected workers or in other words poor supervision on constructive workers habits in our large city of Isfahan cement contact dermatitis is relatively high especially among cement factory workers and constructive personnel. PURPOSES: To investigate the prevalence rate of cement contact dermatitis in cement factory workers in Isfahan. METHODS: A case-control clinical study was carried out by randomly selecing 150 factory workders and 150 official clerks in a cement factory in Isfahan in 2001. After a complete physical examination, data was recorded in observational checklists. FINDINGS: The percentages of contact dermatitis prevalences in the first and the second groups were 22% and 5.3% respectively. About 60% of cement workers with contact dermatitis were between 30-40 years of age. There was a direct relationship with age in both groups of the workers. In the high-exposure group, the hand eczema along was 70% but in the other group the percentage of involvement was the same in exposed and unexposed anatomical areas. CONCLUSIONS: There was a direct relationship between occurrence and the severity of involvement and duration of contact in the first group. Cent percent of cement workers had contact dermatitis after 10 or less years, but the percentage among the other group was 35%. LIMITATION: Irritant contact dermatitis to cement has not been detected.

Use of residual wood in the cement manufacturing process

International Nuclear Information System (INIS)

Gue, R.

2005-01-01

This PowerPoint presentation discussed the use of wood residuals in the cement manufacturing process. An outline of the cement manufacturing process was presented. Raw materials are combined in exact proportions to create a chemically correct mix, which is then pulverized in a mill. The mix is then burned in a kiln. The end product is cooled to form the pellet sized material known as clinker, which is then milled to form cement. The combustion and destruction characteristics of a cement kiln were presented. Modern cement kilns require approximately 3.2 Gj of energy to produce one tonne of cement. It was noted that wood residuals do not contain halogens, sulfur or other materials detrimental to the cement manufacturing process. Possible injection points for kilns were presented. Various studies have shown that wood residuals can be safely used as a fuel in the manufacture of cement. Environmental benefits derived from using wood included the complete destruction of organic portions, and the fact that residual ash becomes an indistinguishable part of the final product. It was concluded that wood residual materials are a satisfactory alternative fuel for the cement industry. tabs., figs

physico-chemical studies on polymer impregnated blending cement mortar composite

International Nuclear Information System (INIS)

Abdel-Rahman, H.A.

2001-01-01

as the increasing of the demand on a specific performance characteristics in concrete such as improved strength, low heat, sulfate resistance, improved impermeability and certain other applications. some of the industrial waste materials such as the blast-furnace slag, silica fume and fly ash were mixed with the cement clinker to produce blended cement . the use of these materials modifies the strength, pore structure and permeability of hardened cement mortar or concrete. the incorporation of blast furnace slag and silica fume in the hardened blended cement mortar or concrete is a common practice recently due to technological, economical and environmental benefits

Cement dust exposure-related emphysema in a construction worker

Directory of Open Access Journals (Sweden)

V Karkhanis

2011-01-01

Full Text Available Although, smoking is considered the most important predisposing factor in development of emphysema; environmental exposures also play an important role. There have been several studies on work related respiratory symptoms and ventilatory disorders among employees of cement industry. We report a case of cement exposure related emphysema in 75 years old woman construction worker.

Oxalate Acid-Base Cements as a Means of Carbon Storage

Science.gov (United States)

Erdogan, S. T.

2017-12-01

Emission of CO2 from industrial processes poses a myriad of environmental problems. One such polluter is the portland cement (PC) industry. PC is the main ingredient in concrete which is the ubiquitous binding material for construction works. Its production is responsible for 5-10 % of all anthropogenic CO2 emissions. Half of this emission arises from the calcination of calcareous raw materials and half from kiln fuel burning and cement clinker grinding. There have long been efforts to reduce the carbon footprint of concrete. Among the many ways, one is to bind CO2 to the phases in the cement-water paste, oxides, hydroxides, and silicates of calcium, during early hydration or while in service. The problem is that obtaining calcium oxide cheaply requires the decarbonation of limestone and the uptake of CO2 is slow and limited mainly to the surface of the concrete due to its low gas permeability. Hence, a faster method to bind more CO2 is needed. Acid-base (AB) cements are fast-setting, high-strength systems that have high durability in many environments in which PC concrete is vulnerable. They are made with a powder base such as MgO and an acid or acid salt, like phosphates. Despite certain advantages over PC cement systems, AB cements are not feasible, due to their high acid content. Also, the phosphoric acid used comes from non-renewable sources of phosphate. A potential way to reduce the drawbacks of using phosphates could be to use organic acids. Oxalic acid or its salts could react with the proper powder base to give concrete that could be used for infrastructure hence that would have very high demand. In addition, methods to produce oxalates from CO2, even atmospheric, are becoming widespread and more economical. The base can also be an industrial byproduct to further lower the environmental impact. This study describes the use of oxalic acid and industrial byproducts to obtain mortars with mechanical properties comparable to those of PC mortars. It is

Energy Efficient Microwave Hybrid Processing of Lime for Cement, Steel, and Glass Industries

Energy Technology Data Exchange (ETDEWEB)

Fall, Morgana L; Yakovlev, Vadim; Sahi, Catherine; Baranova, Inessa; Bowers, Johnney G; Esquenazi\t, Gibran L

2012-02-10

MAT in the US lime industry. This estimate showed that 7.3 TBTU/year could be saved, with reduction of 270 MMlbs of CO2 emissions, and $29 MM/year in economic savings. Taking into account estimates for MAT implementation in the US cement industry, an additional 39 TBTU/year, 3 Blbs of CO2 and $155 MM/year could be saved. One of the main remaining barriers to commercialization of MAT for the lime and cement industries is the sheer size of production. Through this project, it was realized that a production size MAT rotary calciner was not feasible, and a different approach was adapted. The concept of a microwave post heat section located in the upper portion of the cooler was devised and appears to be a more realistic approach for MAT implementation. Commercialization of this technology will require (1) continued pilot scale calcining demonstrations, (2) involvement of lime kiln companies, and (3) involvement of an industrial microwave equipment provider. An initial design concept for a MAT post-heat treatment section was conceived as a retrofit into the cooler sections of existing lime rotary calciners with a 1.4 year payback. Retrofitting will help spur implementation of this technology, as the capital investment will be minimal for enhancing the efficiency of current rotary lime kilns. Retrofits would likely be attractive to lime manufacturers, as the purchase of a new lime kiln is on the order of a $30 million dollar investment, where as a MAT retrofit is estimated on the order of $1 million. The path for commercialization lies in partnering with existing lime kiln companies, who will be able to implement the microwave post heat sections in existing and new build kilns. A microwave equipment provider has been identified, who would make up part of the continued development and commercialization team.

Incinerated sewage sludge ash as alternative binder in cement-based materials

DEFF Research Database (Denmark)

Krejcirikova, Barbora; Goltermann, Per; Hodicky, Kamil

2013-01-01

Sewage sludge ash is characterized by its pozzolanic properties, as cement is. This predetermines its use in a substitution of cement and cementitious materials. Utilization of sewage sludge ash does not only decrease the consumption of cement, one of the largest cause of CO2 emissions, but also...... it can minimize the need of ash landfill disposal. The objective of this study is to show potential use of incinerated sewage sludge ash (ISSA), an industrial byproduct, as possible binder in cement-based materials. Chemical and mechanical characteristics are presented and compared with results obtained...

INEL studies concerning solidification of low-level waste in cement

International Nuclear Information System (INIS)

Mandler, J.W.

1989-01-01

The Idaho National Engineering Laboratory (INEL) has performed numerous studies addressing issues concerning the solidification of low-level radioactive waste in cement. These studies have been performed for both the Nuclear Regulatory Commission (NRC) and the Department of Energy (DOE). This short presentation will only outline the major topics addressed in some of these studies, present a few conclusions, and identify some of the technical concerns we have. More details of the work and pertinent results will be given in the Working Group sessions. The topics that have been addressed at the INEL which are relevant to this Workshop include (1) solidification of ion-exchange resins and evaporator waste in cement at commercial nuclear power plants, (2) leachability and compressive strength of power plant waste solidified in cement, (3) suggested guidelines for preparation of a solid waste process control program (PCP), (4) cement solidification of EPICOR-II resin wastes, and (5) performance testing of cement-solidified EPICOR-II resin wastes

77 FR 42367 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

Science.gov (United States)

2012-07-18

... and 63 National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing... Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry and Standards of... manufacturing plants. Federal government Not affected. State/local/tribal government.... Portland cement...

Effects of Particle Size and Cement Replacement of LCD Glass Powder in Concrete

Directory of Open Access Journals (Sweden)

Seong Kyum Kim

2017-01-01

Full Text Available The high quality liquid crystal display (LCD processing waste glass (LPWG generated from the manufacturing process of Korea’s LCD industries, having the world’s highest technological level and production, was finely ground into particles smaller than cement particles (higher fineness than OPC to verify their applicability and performance as a replacement for cement. For a concrete mix having a W/B ratio of 0.44, cement was replaced with LPWG glass powder (LGP at ratios of 5, 10, 15, and 20% (LGP12 and 5 and 10% (LGP5 according to the particle size to prepare test cylinder specimens, which were tested with respect to air contents, slump in fresh concrete, and compressive strength and splitting tensile strength of hardened concrete. The microstructure of the concrete specimens was analyzed through Scanning Electron Microscopy (SEM, Energy Dispersive X-ray (EDX, and a Mercury Intrusion Porosimetry (MIP. Replacement of cement with LGP for cement could effectively decrease the quantity of cement used due to the excellent performance of LGP. It may positively contribute to the sustainable development of the cement industry as well as waste recycling and environment conservation on a national scale.

Evaluation of Technical Efficiency in Indian Sugar Industry: An Application of Full Cumulative Data Envelopment Analysis

Directory of Open Access Journals (Sweden)

Sunil KUMAR

2012-05-01

Full Text Available This study focuses on the inter-temporal and inter-state variations in technical and scale efficiency levels of Indian sugar industry. In the first stage, full cumulative data envelopment analysis (FCDEA is used to derive efficiency scores for 12 major sugar producing states. The panel data truncated regression is employed in the second stage to assess the key factors explaining the observed variations in the efficiency levels. The results suggest that the extent of technical inefficiency in Indian sugar industry is about 35.5 percent per annum, and the observed technical inefficiency stems primarily due to managerial inefficiency rather scale inefficiency. Also, a precipitous decline in the level of technical efficiency has been noticed in the postreforms period relative to the level observed in the pre-reforms period. The availability of skilled labour and profitability have been found to be most significant determinants of technical efficiency in Indian sugar industry.

Feasibility of backfilling mines using cement kiln dust, fly ash, and cement blends

Directory of Open Access Journals (Sweden)

Beltagui H.

2018-01-01

Full Text Available Cement kiln dust (CKD is an industrial by-product of the cement manufacturing process, the composition of which can vary widely. Recent years of using alternative fuels have resulted in higher chloride and alkali contents within CKDs; as such, this limits the applications in which CKDs can be utilised. Using a CKD containing a high free lime content of 29.5%, it is shown that this CKD is capable of activating pulverized fuel ash (PFA due to its high alkalinity, which can be utilised in low strength un-reinforced applications. One potential application involves the backfill of mines, reducing the need for continuous maintenance of the mine. This study focuses on the compressive strength achieved by various blends of CKD, PFA, and cement. Samples were hand mixed and compacted in 100 mm x 50 mm diameter cylinders, and unconfined compressive strength measurements taken at 28 and 56 days. The hydration products were assessed through the use of x-ray diffraction and thermogravimetric analysis. Aiming to maximise the use of CKD at a water to binder (w/b ratio of 0.2, it was found that the maximum CKD content possible to achieve the required strength was 90% CKD blended with 10% cement.

Impact of Environmental Regulation and Technical Progress on Industrial Carbon Productivity: An Approach Based on Proxy Measure

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Huan Zhang

2016-08-01

Full Text Available This research aims to study the main influencing factors of China’s industrial carbon productivity by incorporating environmental regulation and technical progress into an econometric model. The paper focuses on data from 35 of China’s industrial sectors and covers the period from 2006 to 2014, in order to examine the impact of environmental regulation and technical progress on carbon productivity. Methods applied include panel fixed effect model, panel random effect model and two stage least squares with instrumental variables (IV-2SLS. The effect of environmental regulation and technical progress has industrial heterogeneity. The paper subdivides industrial sectors into capital and technology intensive, resource intensive and labor intensive sectors according to factor intensiveness. The estimation results of the subgroups have uncovered that for capital and technology intensive and resource intensive sectors, environmental regulation has a more significant impact than technical progress; while for labor intensive sectors, innovation more significantly influences carbon productivity. In addition, foreign direct investment (FDI and industrialization level facilitate improving carbon productivity for the full sample. By contrast, industrial structure inhibits the overall industrial carbon productivity. The industry-specific results indicate that for capital and technology intensive sectors, optimizing of the industrial structure can improve carbon productivity; for resource intensive sectors, FDI and energy consumption structure should be emphasized more; for labor intensive sectors, industrialization levels help enhance carbon productivity. Finally the industrial sector-specific policy suggestions are proposed.

VUJE experience with cementation of liquid and wet radioactive waste

International Nuclear Information System (INIS)

Kravarik, Kamil; Holicka, Zuzana; Pekar, Anton; Zatkulak, Milan

2011-01-01

Liquid and wet LLW generated during operation as well as decommissioning of NPPs is treated with different methods and fixed in a suitable fixation matrix so that a final product meets required criteria for its disposal in a final repository. Cementation is an important process used for fixation of liquid and wet radioactive waste such as concentrate, spent resins and sludge. Active cement grout is also used for fixation of low level solid radioactive waste loaded in final packing containers. VUJE Inc. has been engaged in research of cementation for long. The laboratory for analyzing radioactive waste properties, prescription of cementation formulation and estimation of final cement product properties has been established. Experimental, semi-production cementation plant has been built to optimize operation parameters of cementation. VUJE experience with cementation of liquid and wet LLW is described in the presented paper. VUJE has assisted in commissioning of Jaslovske Bohunice Treatment Centre. Cement formulations for treatment of concentrate, spent resins and sludge have been developed. Research studies on the stability of a final concrete packaging container for disposal in repository have been performed. Gained experience has been further utilized for design and manufacture of several cementation plants for treatment of various liquid and wet LLW. Their main technological and technical parameters as well as characterization of treated waste are described in the paper. Applications include the Mochovce Final Treatment Centre, Movable Cementation Facility utilizing in-drum mixing for treatment of sludge, Cementation Facility for treatment of tritiated water in Latvia and Cementation Facility for fixation of liquid and solid institutional radioactive waste in Bulgaria, which utilizes lost stirrer mixer. (author)

Technical writing versus technical writing

Science.gov (United States)

Dillingham, J. W.

1981-01-01

Two terms, two job categories, 'technical writer' and 'technical author' are discussed in terms of industrial and business requirements and standards. A distinction between 'technical writing' and technical 'writing' is made. The term 'technical editor' is also considered. Problems inherent in the design of programs to prepare and train students for these jobs are discussed. A closer alliance between industry and academia is suggested as a means of preparing students with competent technical communication skills (especially writing and editing skills) and good technical skills.

Application of precise MPD & pressure balance cementing technology

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Yong Ma

2018-03-01

Full Text Available The precise managed pressure drilling (MPD technology is mainly used to deal with the difficulties encountered when oil and gas open hole sections with multiple pressure systems and the strata with narrow safety density window are drilled through. If its liner cementing is carried out according to the conventional method, lost circulation is inevitable in the process of cementing while the displacement efficiency of small-clearance liner cementing is satisfied. If the positive and inverse injection technology is adopted, the cementing quality cannot meet the requirements of later well test engineering of ultradeep wells. In this paper, the cementing operation of Ø114.3 mm liner in Well Longgang 70 which was drilled in the Jiange structure of the Sichuan Basin was taken as an example to explore the application of the cementing technology based on the precise MPD and pressure balancing method to the cementing of long open-hole sections (as long as 859 m with both high and low pressures running through multiple reservoirs. On the one hand, the technical measures were taken specifically to ensure the annulus filling efficiency of slurry and the pressure balance in the whole process of cementing. And on the other hand, the annulus pressure balance was precisely controlled by virtue of precise MPD devices and by injecting heavy weight drilling fluids through central pipes, and thus the wellbore pressure was kept steady in the whole process of cementing in the strata with narrow safety density window. It is indicated that Ø114.3 mm liner cementing in this well is good with qualified pressure tests and no channeling emerges at a funnel during the staged density reduction. It is concluded that this method can enhance the liner cementing quality of complex ultradeep gas wells and improve the wellbore conditions for the later safe well tests of high-pressure gas wells. Keywords: Ultradeep well, Liner cementing, Narrow safety density window, Precise

Low pH Cements

International Nuclear Information System (INIS)

Savage, David; Benbow, Steven

2007-05-01

The development of low-pH cements for use in geological repositories for radioactive waste stems from concerns over the potential for deleterious effects upon the host rock and other EBS materials (notably bentonite) under the hyperalkaline conditions (pH > 12) of cement pore fluids. Low pH cement (also known as low heat cement) was developed by the cement industry for use where large masses of cement (e.g. dams) could cause problems regarding heat generated during curing. In low pH cements, the amount of cement is reduced by substitution of materials such as fly ash, blast furnace slag, silica fume, and/or non-pozzolanic silica flour. SKB and Posiva have ruled out the use of blast furnace slag and fly-ash and are focusing on silica fume as a blending agent. Currently, no preferred composition has been identified by these agencies. SKB and Posiva have defined a pH limit ≤ 11 for cement grout leachates. To attain this pH, blending agents must comprise at least 50 wt % of dry materials. Because low pH cement has little, or no free portlandite, the cement consists predominantly of calcium silicate hydrate (CSH) gel with a Ca/Si ratio ≤ 0.8. Although there are potential implications for the performance of the spent fuel and cladding due to the presence of hyperalkaline fluids from cement, the principal focus for safety assessment lies with the behaviour of bentonite. There are a number of potential constraints on the interaction of hyperalkaline cement pore fluids with bentonite, including mass balance, thermodynamic issues, mass transport, and kinetics, but none of these is likely to be limiting if conventional OPC cements are employed in repository construction. Nevertheless: Low-pH cements may supply approximately 50 % less hydroxyl ions than conventional OPC for a given volume of cement, but mass balance constraints are complicated by the uncertainty concerning the type of secondary minerals produced during cement-bentonite interaction. The change of aqueous

Low pH Cements

Energy Technology Data Exchange (ETDEWEB)

Savage, David; Benbow, Steven [Quintessa Ltd., Henley-on-Thames (United Kingdom)

2007-05-15

The development of low-pH cements for use in geological repositories for radioactive waste stems from concerns over the potential for deleterious effects upon the host rock and other EBS materials (notably bentonite) under the hyperalkaline conditions (pH > 12) of cement pore fluids. Low pH cement (also known as low heat cement) was developed by the cement industry for use where large masses of cement (e.g. dams) could cause problems regarding heat generated during curing. In low pH cements, the amount of cement is reduced by substitution of materials such as fly ash, blast furnace slag, silica fume, and/or non-pozzolanic silica flour. SKB and Posiva have ruled out the use of blast furnace slag and fly-ash and are focusing on silica fume as a blending agent. Currently, no preferred composition has been identified by these agencies. SKB and Posiva have defined a pH limit {<=} 11 for cement grout leachates. To attain this pH, blending agents must comprise at least 50 wt % of dry materials. Because low pH cement has little, or no free portlandite, the cement consists predominantly of calcium silicate hydrate (CSH) gel with a Ca/Si ratio {<=} 0.8. Although there are potential implications for the performance of the spent fuel and cladding due to the presence of hyperalkaline fluids from cement, the principal focus for safety assessment lies with the behaviour of bentonite. There are a number of potential constraints on the interaction of hyperalkaline cement pore fluids with bentonite, including mass balance, thermodynamic issues, mass transport, and kinetics, but none of these is likely to be limiting if conventional OPC cements are employed in repository construction. Nevertheless: Low-pH cements may supply approximately 50 % less hydroxyl ions than conventional OPC for a given volume of cement, but mass balance constraints are complicated by the uncertainty concerning the type of secondary minerals produced during cement-bentonite interaction. The change of aqueous

Evaluation of exposure to the airborne asbestos in an asbestos cement sheet manufacturing industry in Iran.

Science.gov (United States)

Panahi, Davood; Kakooei, Hossein; Marioryad, Hossein; Mehrdad, Ramin; Golhosseini, Mohammad

2011-07-01

Iran imports nearly 55,000 tons of Chrysotile asbestos per year and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, airborne asbestos concentrations during AC sheet manufacturing were measured. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM), with energy-dispersive X-ray analysis. Airborne total fiber concentrations of 45 personal samples were analyzed by phase contrast microscopy. The results have highlighted that 15.5% of samples exceed the threshold limit value (TLV) established the American Conference of Governmental Industrial Hygienists, which is 0.1 fiber per milliliter (f/ml). Personal monitoring of asbestos fiber levels indicated a ranged from 0.02 ± 0.01 to 0.16 ± 0.03 f/ml. The geometrical mean was 0.05 ± 1.36 f/ml, which is considerably lower than the TLV. SEM data demonstrate that the fibrous particles consisted, approximately, of Chrysotile (55.89%) and amphiboles (44.11%). We conclude that the industrial consumption of imported Chrysotile asbestos is responsible for the high airborne amphibole asbestos levels in the AC sheet industry. More research is needed to improve characterization of occupational exposures by fiber size and concentration in a variety of industries.

Radiobiological waste treatment-ashing treatment and immobilization with cement

Energy Technology Data Exchange (ETDEWEB)

Shengtao, Feng; Li, Gong; Li, Cheng; Benli, Wang; Lihong, Wang [China Inst. for Radiation Protection, Taiyuan, Shanxi (China)

1997-02-01

This report describes the results of the study on the treatment of radioactive biological waste in the China Institute for Radiation Protection (CIRP). The possibility of radiobiological waste treatment was investigated by using a RAF-3 type rapid ashing apparatus together with the immobilization of the resulted ash. This rapid ashing apparatus, developed by CIRP, is usually used for pretreatment of samples prior to chemical analysis and physical measurements. The results show that it can ash 3 kg of animal carcasses a batch, the ashing time is 5-7 h and the ash content is less than 4 wt%. The ashing temperature not exceeding 450 deg. C was used without any risk of high losses of radionuclides. The ash from the rapid ashing apparatus was demonstrated to be immobilized with ordinary silicate cement. The optimum cement/ash/water formulation of the cemented waste form was 35 {+-} 5 wt% cement, 29 {+-} 2 wt% water, and 36 {+-} 6 wt% ash. The performance of the waste form was in compliance with the technical requirements except for impact resistance. Mixing additives in immobilization formulations can improve the performance of the cemented ash waste form. The additives chosen were DH{sub 4A} flow promoter as a cement additive and vermiculite or zeolite as a supplement. The recommended formulation, i.e. an improved formulation of the cemented ash waste form is that additives DH{sub 4A} flow promoter and vermiculite (or zeolite) are added on the ground of optimum cement/ash/water formulation of the cemented waste form, the dosage of water, DH{sub 4A} and vermiculite (or zeolite) is 70 wt%, 0.5 wt% and {<=} 5 wt% of the cement dosage, respectively. The cemented ash waste forms obtained meet all the requirements for disposal. (author). 12 refs, 7 figs, 13 tabs.

Radiobiological waste treatment-ashing treatment and immobilization with cement

International Nuclear Information System (INIS)

Feng Shengtao; Gong Li; Cheng Li; Wang Benli; Wang Lihong

1997-01-01

This report describes the results of the study on the treatment of radioactive biological waste in the China Institute for Radiation Protection (CIRP). The possibility of radiobiological waste treatment was investigated by using a RAF-3 type rapid ashing apparatus together with the immobilization of the resulted ash. This rapid ashing apparatus, developed by CIRP, is usually used for pretreatment of samples prior to chemical analysis and physical measurements. The results show that it can ash 3 kg of animal carcasses a batch, the ashing time is 5-7 h and the ash content is less than 4 wt%. The ashing temperature not exceeding 450 deg. C was used without any risk of high losses of radionuclides. The ash from the rapid ashing apparatus was demonstrated to be immobilized with ordinary silicate cement. The optimum cement/ash/water formulation of the cemented waste form was 35 ± 5 wt% cement, 29 ± 2 wt% water, and 36 ± 6 wt% ash. The performance of the waste form was in compliance with the technical requirements except for impact resistance. Mixing additives in immobilization formulations can improve the performance of the cemented ash waste form. The additives chosen were DH 4A flow promoter as a cement additive and vermiculite or zeolite as a supplement. The recommended formulation, i.e. an improved formulation of the cemented ash waste form is that additives DH 4A flow promoter and vermiculite (or zeolite) are added on the ground of optimum cement/ash/water formulation of the cemented waste form, the dosage of water, DH 4A and vermiculite (or zeolite) is 70 wt%, 0.5 wt% and ≤ 5 wt% of the cement dosage, respectively. The cemented ash waste forms obtained meet all the requirements for disposal. (author). 12 refs, 7 figs, 13 tabs

Estimation of CO2 emissions from China’s cement production: Methodologies and uncertainties

International Nuclear Information System (INIS)

Ke, Jing; McNeil, Michael; Price, Lynn; Khanna, Nina Zheng; Zhou, Nan

2013-01-01

In 2010, China’s cement output was 1.9 Gt, which accounted for 56% of world cement production. Total carbon dioxide (CO 2 ) emissions from Chinese cement production could therefore exceed 1.2 Gt. The magnitude of emissions from this single industrial sector in one country underscores the need to understand the uncertainty of current estimates of cement emissions in China. This paper compares several methodologies for calculating CO 2 emissions from cement production, including the three main components of emissions: direct emissions from the calcination process for clinker production, direct emissions from fossil fuel combustion and indirect emissions from electricity consumption. This paper examines in detail the differences between common methodologies for each emission component, and considers their effect on total emissions. We then evaluate the overall level of uncertainty implied by the differences among methodologies according to recommendations of the Joint Committee for Guides in Metrology. We find a relative uncertainty in China’s cement-related emissions in the range of 10 to 18%. This result highlights the importance of understanding and refining methods of estimating emissions in this important industrial sector. - Highlights: ► CO 2 emission estimates are critical given China’s cement production scale. ► Methodological differences for emission components are compared. ► Results show relative uncertainty in China’s cement-related emissions of about 10%. ► IPCC Guidelines and CSI Cement CO 2 and Energy Protocol are recommended

Mechanism and Modelling for Sorption of Toxic Ion on Cement Kiln Dust

International Nuclear Information System (INIS)

EI- Dakroury, A.; Sayed, M.S.; EL- Sherif, E.

2009-01-01

Cement manufacturing is a critically important industry in Egypt. These industrial by-product and waste materials must be managed responsibly to insure a clean and safe environment. Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. Cement kiln dust is a waste residue composed chiefly of oxidized, anhydrous, micron - sized particles generated as a by product of the manufacture of Portland cement. The use of cement kiln dust as adsorbent in wastewater treatment has a great attention as cheap material and clay structure. This work will discuss the basic characteristics of CKD physical and chemical properties and regulatory requirements: The batch removal of Cr(VI) from aqueous solution using low cost adsorbents such as cement kiln dust under different experimental conditions. The influences of initial Cr (VI) ion concentration (20 to 300 mg1-1) and ph (1 to 4) were investigated in this study. Adsorption of Cr (VI) is highly ph-dependent and the results indicate that the optimum ph for the removal was found to be 1 for CKD. A comparison of kinetic models applied to the adsorption of Cr (VI) ions on the CKD was evaluated for the pseudo first order, the pseudo second-order, Elovich and intra particle diffusion kinetic models, respectively. The results showed that the pseudo second-order kinetic model was found to correlate the experimental data well

50-year of the Technical Assistance Service to Industry (SATI): notes from a heterodoxy

International Nuclear Information System (INIS)

Enriquez, Santiago N.

2011-01-01

This report is in honor of the 50° creation anniversary of the Service of Technical Assistance to Industry (SATI),a service with no background in Argentina. This occasion is appropriate to think the historical conditions which made possible the existence of the SATI in the National Atomic Energy Commission. Secondly, this report describes its operative characteristics and its achievements in different fields: from the technical and industry-learning aspects, up to the development of the conception about the relation between Science, Technology and Society. (author) [es

New developments of high dust-SCR technology in the cement industry results of pilot tests in Solnhofen and development state of a full scale SCR unit; Nouveaux developpements de la technologie SCR ''High Dust'' dans l'industrie du ciment - resultats de tests pilotes a Solnhoffen et etat de developpement d'une unite pilote a l'echelle

Energy Technology Data Exchange (ETDEWEB)

Samant, G. [Lurgi Energie und Entsorgung GmbH, Frankfurt (Germany); Sauter, G. [Soinhofer Portland Zementwerke AG, Solnhofen (Germany); Haug, N. [Agence Federale de l' Environnement, Berlin (Germany)

2001-07-01

The production of clinker in the cement industry involve the formation of nitrous oxides, and the emission limits are becoming more stringent from year to year. The added up total NOx emissions from the European cement industry amounts at present approx. 450.000 Mg/year. As such it is high time for the decision to develop and implement a technology to reduce NOx-emissions. At present SCR technology which is implemented in the glass industry, waste incineration and power plants seems to be the best economical and ecological solution for cement industry. In the period time from 1997 to the end of 1999 pilot plant test work was carried out by the companies 'Solnhofer Portland Zementwerke AG' and 'mg Engineering Lurgi' in the cement plant in Solnhofen. The results of pilot plan test work show that NOx reduction rates above 90% with NH{sub 3} slip less then 5 vppm can be achieved. The results of the test work with different type of catalysts are discussed. Based on the results of the test work a suitable SCR-process for cement industry is developed. At present a High-Dust-SCR demonstration plant at 'Solnhofer Portland Zementwerke AG' with the help of German Federal Environmental Agency, UBA-Berlin, is under commissioning and going on stream. (authors)

Analysis of cement superplasticizers and grinding aids a literature survey

International Nuclear Information System (INIS)

Ervanne, H.; Hakanen, M.

2007-04-01

This literature survey reviews the methods for analysis of cement plasticizers and organic grounding aids in cement solutions in preparation of grouts/concrete and methods for determination of plasticizers and grinding aids in groundwater conditions. The survey focuses on three different types of superplasticizers: sulphonated naphthalene condensates, sulphonated melamine condensates and polycarboxylates. There are various organic grinding aids, such as alkanolamines, glycols or phenolic compounds, used in the cement industry. This review is concerned with the following compounds: triethylenetetramine, tetraethylenepentamine, diethanolamine, triethanolamine, triisopropanolamine, ethyleneglycol, diethyleneglycol, aminoethylethanolamine, hydroxyethyl diethylenetriamine and phenol. (orig.)

Statistical study of chemical additives effects in the waste cementation

International Nuclear Information System (INIS)

Tello, Cledola C.O. de; Diniz, Paula S.; Haucz, Maria J.A.

1997-01-01

This paper presents the statistical study, that was carried out to analyse the chemical additives effect in the waste cementation process. Three different additives from two industries were tested: set accelerator, set retarder and super plasticizers, in cemented pates with and without bentonite. The experiments were planned in accordance with the 2 3 factorial design, so that the effect of each type of additive, its quantity and manufacturer in cemented paste and specimens could be evaluated. The results showed that the use of these can improve the cementation process and the product. The admixture quantity and the association with bentonite were the most important factors affecting the process and product characteristics. (author). 4 refs., 9 figs., 4 tabs

Evaluation of Portland cement from X-ray diffraction associated with cluster analysis

International Nuclear Information System (INIS)

Gobbo, Luciano de Andrade; Montanheiro, Tarcisio Jose; Montanheiro, Filipe; Sant'Agostino, Lilia Mascarenhas

2013-01-01

The Brazilian cement industry produced 64 million tons of cement in 2012, with noteworthy contribution of CP-II (slag), CP-III (blast furnace) and CP-IV (pozzolanic) cements. The industrial pole comprises about 80 factories that utilize raw materials of different origins and chemical compositions that require enhanced analytical technologies to optimize production in order to gain space in the growing consumer market in Brazil. This paper assesses the sensitivity of mineralogical analysis by X-ray diffraction associated with cluster analysis to distinguish different kinds of cements with different additions. This technique can be applied, for example, in the prospection of different types of limestone (calcitic, dolomitic and siliceous) as well as in the qualification of different clinkers. The cluster analysis does not require any specific knowledge of the mineralogical composition of the diffractograms to be clustered; rather, it is based on their similarity. The materials tested for addition have different origins: fly ashes from different power stations from South Brazil and slag from different steel plants in the Southeast. Cement with different additions of limestone and white Portland cement were also used. The Rietveld method of qualitative and quantitative analysis was used for measuring the results generated by the cluster analysis technique. (author)

Development of nanosilica bonded monetite cement from egg shells

Energy Technology Data Exchange (ETDEWEB)

Zhou, Huan, E-mail: huanzhou@cczu.edu.cn [Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu (China); Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Luchini, Timothy J.F.; Boroujeni, Nariman Mansouri [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Agarwal, Anand K.; Goel, Vijay K. [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Division of Dentistry, The University of Toledo, Toledo, OH (United States)

2015-05-01

This work represents further effort from our group in developing monetite based calcium phosphate cements (CPC). These cements start with a calcium phosphate powder (MW-CPC) that is manufactured using microwave irradiation. Due to the robustness of the cement production process, we report that the starting materials can be derived from egg shells, a waste product from the poultry industry. The CPC were prepared with MW-CPC and aqueous setting solution. Results showed that the CPC hardened after mixing powdered cement with water for about 12.5 ± 1 min. The compressive strength after 24 h of incubation was approximately 8.45 ± 1.29 MPa. In addition, adding colloidal nanosilica to CPC can accelerate the cement hardening (10 ± 1 min) process by about 2.5 min and improve compressive strength (20.16 ± 4.39 MPa), which is more than double the original strength. The interaction between nanosilica and CPC was monitored using an environmental scanning electron microscope (ESEM). While hardening, nanosilica can bond to the CPC crystal network for stabilization. The physical and biological studies performed on both cements suggest that they can potentially be used in orthopedics. - Highlights: • Cement raw powder is derived from egg shells. • A microwave assisted system is used for preparing monetite bone cement. • Colloidal silica is used to reinforce cement.

Development of nanosilica bonded monetite cement from egg shells

International Nuclear Information System (INIS)

Zhou, Huan; Luchini, Timothy J.F.; Boroujeni, Nariman Mansouri; Agarwal, Anand K.; Goel, Vijay K.; Bhaduri, Sarit B.

2015-01-01

This work represents further effort from our group in developing monetite based calcium phosphate cements (CPC). These cements start with a calcium phosphate powder (MW-CPC) that is manufactured using microwave irradiation. Due to the robustness of the cement production process, we report that the starting materials can be derived from egg shells, a waste product from the poultry industry. The CPC were prepared with MW-CPC and aqueous setting solution. Results showed that the CPC hardened after mixing powdered cement with water for about 12.5 ± 1 min. The compressive strength after 24 h of incubation was approximately 8.45 ± 1.29 MPa. In addition, adding colloidal nanosilica to CPC can accelerate the cement hardening (10 ± 1 min) process by about 2.5 min and improve compressive strength (20.16 ± 4.39 MPa), which is more than double the original strength. The interaction between nanosilica and CPC was monitored using an environmental scanning electron microscope (ESEM). While hardening, nanosilica can bond to the CPC crystal network for stabilization. The physical and biological studies performed on both cements suggest that they can potentially be used in orthopedics. - Highlights: • Cement raw powder is derived from egg shells. • A microwave assisted system is used for preparing monetite bone cement. • Colloidal silica is used to reinforce cement

Compressive strength test for cemented waste forms: validation process

International Nuclear Information System (INIS)

Haucz, Maria Judite A.; Candido, Francisco Donizete; Seles, Sandro Rogerio

2007-01-01

In the Cementation Laboratory (LABCIM), of the Development Centre of the Nuclear Technology (CNEN/CDTN-MG), hazardous/radioactive wastes are incorporated in cement, to transform them into monolithic products, preventing or minimizing the contaminant release to the environment. The compressive strength test is important to evaluate the cemented product quality, in which it is determined the compression load necessary to rupture the cemented waste form. In LABCIM a specific procedure was developed to determine the compressive strength of cement waste forms based on the Brazilian Standard NBR 7215. The accreditation of this procedure is essential to assure reproductive and accurate results in the evaluation of these products. To achieve this goal the Laboratory personal implemented technical and administrative improvements in accordance with the NBR ISO/IEC 17025 standard 'General requirements for the competence of testing and calibration laboratories'. As the developed procedure was not a standard one the norm ISO/IEC 17025 requests its validation. There are some methodologies to do that. In this paper it is described the current status of the accreditation project, especially the validation process of the referred procedure and its results. (author)

Employers' Perception of Graduates with Entry-Level Technical Skills from Construction Industry Programs in Ghana and Nigeria

Science.gov (United States)

Acheampong, Philip

2013-01-01

The purpose of this comparative study was to identify the technical skills and abilities needed by prospective employees of construction industries in Ghana and Nigeria. Potential employees were defined here as recent graduates of construction industry programs with entry-level technical skills. The continuous growth in and expansion of these two…

The fundamentals of the radiation thermal technology for cement production

International Nuclear Information System (INIS)

Abramson, I.G.; Kapralova, R.M.; Nikiforov, Yu.V.; Egorov, G.B.; Vaisman, A.F.

1995-01-01

The fundamentals of principally new radiation thermal way of cement production are presented. The peculiarities of qualities and structure of clinker obtained by this way are given. The technical economic advantages of the new technology are shown

Sulfoaluminate-belite cement from low-calcium fly ash and sulfur-rich and other industrial by-products

Energy Technology Data Exchange (ETDEWEB)

Arjunan, P.; Silsbee, M.R.; Roy, D.M.

1999-08-01

The study describes the preparation and characterization of an environmentally friendly cement with performance characteristics similar to those of Portland cement, from a lime kiln bag house dust, a low-calcium fly ash, and a scrubber sludge. Promising preliminary results show the formation of relatively low-temperature phases calcium sulfoaluminate (4CaO{center{underscore}dot}3Al{sub 2}O{sub 3}{center{underscore}dot}SO{sub 3}) and dicalcium silicate (2CaO{center{underscore}dot}SiO{sub 2}) at {approximately} 1,250 C if nodulized raw means used for clinker preparation and at 1,175 C if powdered raw meal is used as compared to the {approximately} 1,500 C sintering temperature required for Portland cement. Phases of the developed cements were predicted using modified Bogue calculations. Isothermal calorimetric measurements indicate the hydration properties of the cements are comparable to ordinary Portland cement. Mechanical properties and microstructural evaluations also were carried out.

Economic and Technical Assessment of Wood Biomass Fuel Gasification for Industrial Gas Production

Energy Technology Data Exchange (ETDEWEB)

Anastasia M. Gribik; Ronald E. Mizia; Harry Gatley; Benjamin Phillips

2007-09-01

This project addresses both the technical and economic feasibility of replacing industrial gas in lime kilns with synthesis gas from the gasification of hog fuel. The technical assessment includes a materials evaluation, processing equipment needs, and suitability of the heat content of the synthesis gas as a replacement for industrial gas. The economic assessment includes estimations for capital, construction, operating, maintenance, and management costs for the reference plant. To perform these assessments, detailed models of the gasification and lime kiln processes were developed using Aspen Plus. The material and energy balance outputs from the Aspen Plus model were used as inputs to both the material and economic evaluations.

Self-healing polymer cement composites for geothermal wellbore applications

Science.gov (United States)

Rod, K. A.; Fernandez, C.; Childers, I.; Koech, P.; Um, W.; Roosendaal, T.; Nguyen, M.; Huerta, N. J.; Chun, J.; Glezakou, V. A.

2017-12-01

Cement is vital for controlling leaks from wellbores employed in oil, gas, and geothermal operations by sealing the annulus between the wellbore casing and geologic formation. Wellbore cement failure due to physical and chemical stresses is common and can result in significant environmental consequences and ultimately significant financial costs due to remediation efforts. To date numerous alternative cement blends have been proposed for the oil and gas industry. Most of these possess poor mechanical properties, or are not designed to work in high temperature environments. This research investigates novel polymer-cement composites which could function at most geothermal temperatures. Thermal stability and mechanical strength of the polymer is attributed to the formation of a number of chemical interactions between the polymer and cement matrix including covalent bonds, hydrogen bonding, and van der Waals interactions. It has been demonstrated that the bonding between cement and casing is more predictable when polymer is added to cement and can even improve healing of adhesion break when subjected to stresses such as thermal shock. Fractures have also been healed, effectively reducing permeability with fractures up to 0.3-0.5mm apertures, which is two orders of magnitude larger than typical wellbore fractures. Additionally, tomography analysis was used to determine internal structure of the cement polymer composite and imaging reveals that polymers fill fractures in the cement and between the cement and casing. By plugging fractures that occur in wellbore cement, reducing permeability of fractures, both environmental safety and economics of subsurface operations will be improved for geothermal energy and oil and gas production.

A modified PMMA cement (Sub-cement) for accelerated fatigue testing of cemented implant constructs using cadaveric bone.

Science.gov (United States)

Race, Amos; Miller, Mark A; Mann, Kenneth A

2008-10-20

Pre-clinical screening of cemented implant systems could be improved by modeling the longer-term response of the implant/cement/bone construct to cyclic loading. We formulated bone cement with degraded fatigue fracture properties (Sub-cement) such that long-term fatigue could be simulated in short-term cadaver tests. Sub-cement was made by adding a chain-transfer agent to standard polymethylmethacrylate (PMMA) cement. This reduced the molecular weight of the inter-bead matrix without changing reaction-rate or handling characteristics. Static mechanical properties were approximately equivalent to normal cement. Over a physiologically reasonable range of stress-intensity factor, fatigue crack propagation rates for Sub-cement were higher by a factor of 25+/-19. When tested in a simplified 2 1/2-D physical model of a stem-cement-bone system, crack growth from the stem was accelerated by a factor of 100. Sub-cement accelerated both crack initiation and growth rate. Sub-cement is now being evaluated in full stem/cement/femur models.

Quality evaluation of soil-cement-plant residue bricks by the combination of destructive and non-destructive tests

Directory of Open Access Journals (Sweden)

Regis de C. Ferreira

Full Text Available ABSTRACT Residues from agricultural activity can be used to improve the quality of soil-based bricks, constituting an interesting alternative for their destination. The technical quality of soil-cement-plant residue bricks was evaluated by the combination of non-destructive and destructive methods. A predominant clayey soil, Portland cement and residues of husks of both rice and Brachiaria brizantha cv. Marandu (0, 10, 20, 30 and 40%, in mass, in substitution to the 10% cement content were used. The bricks were submitted to destructive (water absorption and compressive strength and nondestructive (ultrasound tests for their physical and mechanical characterization. Results from both destructive and non-destructive tests were combined to determine the quantitative parameter named “anisotropic resistance” in order to evaluate the quality of the bricks. The addition that promoted best technical quality was 10% residue content, regardless of the residue type. The anisotropic resistance proved to be adequate for the technical quality evaluation of the bricks.

Enhancement of cemented waste forms by supercritical CO2 carbonation of standard portland cements

International Nuclear Information System (INIS)

Rubin, J.B.; Carey, J.; Taylor, C.M.V.

1997-01-01

We are conducting experiments on an innovative transformation concept, using a traditional immobilization technique, that may significantly reduce the volume of hazardous or radioactive waste requiring transport and long-term storage. The standard practice for the stabilization of radioactive salts and residues is to mix them with cements, which may include additives to enhance immobilization. Many of these wastes do not qualify for underground disposition, however, because they do not meet disposal requirements for free liquids, decay heat, head-space gas analysis, and/or leachability. The treatment method alters the bulk properties of a cemented waste form by greatly accelerating the natural cement-aging reactions, producing a chemically stable form having reduced free liquids, as well as reduced porosity, permeability and pH. These structural and chemical changes should allow for greater actinide loading, as well as the reduced mobility of the anions, cations, and radionuclides in aboveground and underground repositories. Simultaneously, the treatment process removes a majority of the hydrogenous material from the cement. The treatment method allows for on-line process monitoring of leachates and can be transported into the field. We will describe the general features of supercritical fluids, as well as the application of these fluids to the treatment of solid and semi-solid waste forms. some of the issues concerning the economic feasibility of industrial scale-up will be addressed, with particular attention to the engineering requirements for the establishment of on-site processing facilities. Finally, the initial results of physical property measurements made on portland cements before and after supercritical fluid processing will be presented

Corrosion resistance of cement brick on an organo-mineral base in a hydrogen sulfide medium

Energy Technology Data Exchange (ETDEWEB)

Potapov, A G; Belousov, G A; Pustovalov, V I; Skorikov, B M

1981-01-01

Results are presented of strength tests of cement brick made of different types of cement as a function of the composition of the mixing liquid and storage conditions. It is established that cement brick made of cement on a cinder base mixed in hydrogen sulfide water possesses the highest corrosive resistance to hydrogen sulfide attack. A marked increase in corrosion resistance is observed in cement brick on an organo-mineral base. Results of industrial tests of organo-mineral grouting mortar in a hydrogen sulfide medium are demonstrated.

The asbestos cement container and its characterization program

International Nuclear Information System (INIS)

Kertesz, C.; Oliver, J.; Jaouen, C.

1986-01-01

A new type of packing container is designed in France, by SGN, for the reprocessing wastes conditioning: the asbestos cement container (CAC) made by the industrial process for pipes fabrication. Two types of CAC are studied, differing from each other by their wall thickness. The technology of which SGN is in charge is presented. A characterization program is operated by CEA in view of satisfying to regulatory requirements. Emphasis is placed upon the radionuclides migration study, through different asbestos cement samples

Impact of coal and rice husk ash on the quality and chemistry of cement clinker

International Nuclear Information System (INIS)

Nawaz, S.; Kanwal, S.; Rahim, U.; Sheikh, N.; Shahzad, K.

2012-01-01

Utilization of rice husk as an alternative fuel for coal is of interest due to its availability in huge quantities in Pakistan and also because its combustion is environmental pollution friendly as it generates much less SOX due to its much lower sulphur content (0.1-0.3%) compared to sulphur content in coals, particularly indeginous coals ranging from 0.6-14.8%. The purpose of present study was to examine the impact of co-firing of rice husk and coal on the quality of cement clinker so as to substitute expensive imported coal with the abundantly available cheaper rice husk to reduce the cost of production of the cement. For this investigation raw feed mix (mixture of limestone, clay, bauxite and laterite in predetermined proportions) used for cement manufacture was mixed with predetermined varying proportions of coal ash and rice husk ash and placed inside a muffle furnace at 1200 degree C - 1500 degree C i-e the temperatures prevailing in the industrial cement kilns, for various periods of time to obtain cement clinker. The quality and chemistry of cement clinker thus produced in the laboratory was experimentally studied to ensure the quality of cement clinker that would be obtained by co-firing of rice husk and coal in different proportions in industrial cement kilns as the coal ash and rice husk ash produced during combustion will get mixed with cement clinker in industrial kilns. The results indicated that there was decrease in the Lime Saturation Factor, Free Lime and Tricalcium Silicate (C3S) content and increase in the Dicalcium Silicate (C2S) content by increasing the rice husk ash and decreasing the coal ash proportion in the clinker. (author)

Comparison of the physical and mechanical properties of MTA and portland cement.

Science.gov (United States)

Islam, Intekhab; Chng, Hui Kheng; Yap, Adrian U Jin

2006-03-01

This study evaluated and compared the pH, radiopacity, setting time, solubility, dimensional change, and compressive strength of ProRoot MTA (PMTA), ProRoot MTA (tooth colored formula) (WMTA), white Portland cement (WP), and ordinary Portland cement (OP). The results showed that PMTA and Portland cement have very similar physical properties. However, the radiopacity of Portland cement is much lower than that of PMTA. The compressive strength of PMTA was greater than Portland cement at 28 days. The major constituent of PMTA is Portland cement. Given the low cost of Portland cement and similar properties when compared to PMTA, it is reasonable to consider Portland cement as a possible substitute for PMTA in endodontic applications. However, industrially manufactured Portland cement is not approved currently for use in the United States and therefore no clinical recommendation can be made for its use in the human body. Further in vitro and in vivo tests, especially with regards its biocompatibility, should be conducted to ascertain if it meets the FDA requirements for use as a medical device.

Investment risk evaluation techniques: use in energy-intensive industries and implications for ERDA's Industrial Conservation Program

Energy Technology Data Exchange (ETDEWEB)

None

1977-07-13

The trade-off between risk and rate-of-return in investment evaluations is crucial in assessing the commercial potential of future energy-conservation technologies. The focus of the Industrial Conservation Program at ERDA is to reduce the perceived risks of a given technology to the extent that the private sector will adopt the technology within the normal course of its business operations. These perceived risks may emanate from technical, institutional, or commercial uncertainties, or in many cases they may result merely from a company's or industry's lack of previous experience with a particular technology. Regardless of the source of the risk surrounding a project, the uncertainty it poses to the private sector will serve to inhibit decisions to invest. This study evaluates the treatment of risk in capital investments in certain energy-intensive industries which are the primary targets of ERDA's Industrial Conservation Program. These risks evaluation considerations were placed within a context that includes capital budgeting practices and procedures, organizational considerations, and basic rate-of-return evaluation procedures in the targeted energy-intensive industries (petroleum, chemicals, paper, textiles, cement, food processing, aluminum, steel, glass, and agriculture).

Penetration of natural gas in industrial processes for direct burning: the case of ceramics, cement and glass industries; Penetracao do gas natural em processos industriais de queima direta: caso das industrias ceramica, cimento e vidro

Energy Technology Data Exchange (ETDEWEB)

Berni, Mauro Donizeti; Leite, Alvaro A. Furtado [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Dorileo, Ivo Leandro [Universidade Federal do Mato Grosso (NIEPE/UFMT), Cuiaba, MT (Brazil). Nucleo Interdisciplinar de Estudos em Planejamento Energetico; Bajay, Sergio Valdir [Universidade estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Dept. de Energia], e-mail: bajay@fem.unicamp.com.br

2008-07-01

Industrial sector can use the natural gas (NG) as raw material, as fuel and in co-generation. The NG as fuel is used, predominantly, to produce heat in the Brazilian industries. That rate, both main forms of industrial use of the NG are its direct burning in kilns - when the direct contact is had with the product - and the supply of process heat through boilers, for instance. Direct burning is used in the ceramic, cement and glass industries. This work discuss the penetration opportunity of the NG in the direct burning regarding the fuel oil and other energy that it can substitute, the environmental effects and the co-generation possibilities in each one of the analyzed industrial blanches in this work. (author)

Energy optimization and reduction of carbon footprint in cement manufacturing

Energy Technology Data Exchange (ETDEWEB)

Gallestey, Eduardo; Crosley, Gabriela; Wilson, Andrew; Maier, Urs; Hoppler, Rolf; Boerrnert, Thomas

2010-09-15

Cement producers are large consumers of thermal and electrical energy, which are only available at steadily increasing costs. Efforts to reduce demands by using higher efficiency equipment and substituting -fuels and raw materials to lower production costs have been addressed in recent years. Under the Kyoto Protocol industrialised countries agreed to reduce their collective greenhouse gas emissions. Cement producers as some of the largest emitters of CO2 have been especially challenged to find new and innovative ways to reduce greenhouse gas emissions. This paper summarise some ABB technologies developed to assist the cement industry to meet these goals.

Preterm delivery among people living around Portland cement plants

International Nuclear Information System (INIS)

Yang, C.-Y.; Chang, C.-C.; Tsai, S.-S.; Huang, H.-Y.; Ho, C.-K.; Wu, T.-N.; Sung, F.-C.

2003-01-01

The Portland cement industry is the main source of particulate air pollution in Kaohsiung city. Data in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to Portland cement plants. The prevalence of delivery of preterm birth infants as significantly higher in mothers living within 0-2 km of a Portland cement plant than in mothers living within 2-4 km. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.30 (95% I=1.09-1.54) for the delivery of preterm infants for mothers living close to he Portland cement plants, chosen at the start to be from 0 to 2 km. These data provide further support for the hypothesis that air pollution can affect he outcome of pregnancy

Kinetics of strength gain of biocidal cements

Directory of Open Access Journals (Sweden)

Rodin Aleksandr Ivanovich

Full Text Available Biocorrosion becomes the determinative durability factor of buildings and constructions. Damages of construction materials caused by bacteria, filamentous fungi, actinomycetes constitute a serious danger to the constructions of a building or a structure and to the health of people. Biodeteriorations are typical both in old and new constructions. A great quantity of destruction factors of industrial and residential buildings under the influence of microorganisms was established in practice. Providing products and constructions based on concretes fungicidal and bactericidal properties is an important direction of modern construction material science. The most efficient way to solve this task is creation of biocidal cements. The article presents the results of experimental studies of kinetic dependences of strength gain by biocidal cements by physico-mechanical and physico-chemical analysis methods. The identical velocity character of initial hydration of the developed compositions of biocidal cements is set, as well as a more calm behavior of hardening processes at later terms. It has been established that the compositions of biocidal cements modified by sodium sulfate and sodium fluoride possess the greatest strength.

Formulation of portland composite cement using waste glass as a supplementary cementitious material

Science.gov (United States)

Manullang, Ria Julyana; Samadhi, Tjokorde Walmiki; Purbasari, Aprilina

2017-09-01

Utilization of waste glass in cement is an attractive options because of its pozzolanic behaviour and the market of glass-composite cement is potentially available. The objective of this research is to evaluate the formulation of waste glass as supplementary cementitious material (SCM) by an extreme vertices mixture experiment, in which clinker, waste glass and gypsum proportions are chosen as experimental variables. The composite cements were synthesized by mixing all of powder materials in jar mill. The compressive strength of the composite cement mortars after being cured for 28 days ranges between 229 to 268 kg/cm2. Composite cement mortars exhibit lower compressive strength than ordinary Portland cement (OPC) mortars but is still capable of meeting the SNI 15-7064-2004 standards. The highest compressive strength is obtained by shifting the cement blend composition to the direction of increasing clinker and gypsum proportions as well as reducing glass proportion. The lower compressive strength of composite cement is caused by expansion due to ettringite and ASR gel. Based on the experimental result, the composite cement containing 80% clinker, 15% glass and 5% gypsum has the highest compressive strength. As such, the preliminary technical feasibility of reuse of waste glass as SCM has been confirmed.

Reducing CO2-Emission by using Eco-Cements

Science.gov (United States)

Voit, K.; Bergmeister, K.; Janotka, I.

2012-04-01

CO2 concentration in the air is rising constantly. Globally, cement companies are emitting nearly two billion tonnes/year of CO2 (or around 6 to 7 % of the planet's total CO2 emissions) by producing portland cement clinker. At this pace, by 2025 the cement industry will be emitting CO2 at a rate of 3.5 billion tones/year causing enormous environmental damage (Shi et al., 2011; Janotka et al., 2012). At the dawn of the industrial revolution in the mid-eighteenth century the concentration of CO2 was at a level of ca. 280 ppm. 200 years later at the time of World War II the CO2 level had risen to 310 ppm what results in a rate of increase of 0,15 ppm per year for that period (Shi et al., 2011). In November 2011 the CO2 concentration reached a value of 391 ppm (NOAA Earth System Research Laboratory, 2011), a rise of ca. 81 ppm in 66 years and an increased rate of around 1,2 ppm/year respectively. In the same period cement production in tons of cement has multiplied by a factor of ca. 62 (Kelly & Oss, US Geological Survey, 2010). Thus new CO2-saving eco-cement types are gaining in importance. In these cement types the energy-consuming portland cement clinker is partially replaced by latent hydraulic additives such as blast furnace slag, fly ash or zeolite. These hydraulic additives do not need to be fired in the rotary furnace. They ony need to be pulverized to the required grain size and added to the ground portland cement clinker. Hence energy is saved by skipping the engery-consuming firing process, in addition there is no CO2-degassing as there is in the case of lime burning. Therefore a research project between Austria and Slovakia, funded by the EU (Project ENVIZEO), was initiated in 2010. The main goal of this project is to develop new CEM V eco-types of cements and certificate them for common usage. CEM V is a portland clinker saving cement kind that allows the reduction of clinker to a proportion of 40-64% for CEM V/A and 20-39% for CEM V/B respectively by the

Stabilisation of clayey soils with high calcium fly ash and cement

Energy Technology Data Exchange (ETDEWEB)

S. Kolias; V. Kasselouri-Rigopoulou; A. Karahalios [National Technical University of Athens, Athens (Greece)

2005-02-01

The effectiveness of using high calcium fly ash and cement in stabilising fine-grained clayey soils (CL,CH) was investigated in the laboratory. Strength tests in uniaxial compression, in indirect (splitting) tension and flexure were carried out on samples to which various percentages of fly ash and cement had been added. Modulus of elasticity was determined at 90 days with different types of load application and 90-day soaked CBR values are also reported. Pavement structures incorporating subgrades improved by in situ stabilisation with fly ash and cement were analyzed for construction traffic and for operating traffic. These pavements are compared with conventional flexible pavements without improved subgrades and the results clearly show the technical benefits of stabilising clayey soils with fly ash and cement. In addition TG-SDTA and XRD tests were carried out on certain samples in order to study the hydraulic compounds, which were formed.

The suitability of a supersulfated cement for nuclear waste immobilisation

International Nuclear Information System (INIS)

Collier, N.C.; Milestone, N.B.; Gordon, L.E.; Ko, S.-C.

2014-01-01

Highlights: • We investigate a supersulfated cement for use as a nuclear waste encapsulant. • High powder fineness requires a high water content to satisfy flow requirements. • Heat generation during hydration is similar to a control cement paste. • Typical hydration products are formed resulting in a high potential for waste ion immobilisation. • Paste pH and aluminium corrosion is less than in a control cement paste. - Abstract: Composite cements based on ordinary Portland cement are used in the UK as immobilisation matrices for low and intermediate level nuclear wastes. However, the high pore solution pH causes corrosion of some metallic wastes and undesirable expansive reactions, which has led to alternative cementing systems being examined. We have investigated the physical, chemical and microstructural properties of a supersulfated cement in order to determine its applicability for use in nuclear waste encapsulation. The hardened supersulfated cement paste appeared to have properties desirable for use in producing encapsulation matrices, but the high powder specific surface resulted in a matrix with high porosity. Ettringite and calcium silicate hydrate were the main phases formed in the hardened cement paste and anhydrite was present in excess. The maximum rate of heat output during hydration of the supersulfated cement paste was slightly higher than that of a 9:1 blastfurnace slag:ordinary Portland cement paste commonly used by the UK nuclear waste processing industry, although the total heat output of the supersulfated cement paste was lower. The pH was also significantly lower in the supersulfated cement paste. Aluminium hydroxide was formed on the surface of aluminium metal encapsulated in the cement paste and ettringite was detected between the aluminium hydroxide and the hardened cement paste

The suitability of a supersulfated cement for nuclear waste immobilisation

Energy Technology Data Exchange (ETDEWEB)

Collier, N.C., E-mail: nick.collier@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Milestone, N.B. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Callaghan Innovation, 69 Gracefield Road, PO Box 31310, Lower Hutt 5040 (New Zealand); Gordon, L.E. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Geopolymer and Minerals Processing Group, Department of Chemical and Biomolecular Engineering, University of Melbourne, Parkville, Victoria 3010 (Australia); Ko, S.-C. [Holcim Technology Ltd, Hagenholzstrasse 85, CH-8050 Zurich (Switzerland)

2014-09-15

Highlights: • We investigate a supersulfated cement for use as a nuclear waste encapsulant. • High powder fineness requires a high water content to satisfy flow requirements. • Heat generation during hydration is similar to a control cement paste. • Typical hydration products are formed resulting in a high potential for waste ion immobilisation. • Paste pH and aluminium corrosion is less than in a control cement paste. - Abstract: Composite cements based on ordinary Portland cement are used in the UK as immobilisation matrices for low and intermediate level nuclear wastes. However, the high pore solution pH causes corrosion of some metallic wastes and undesirable expansive reactions, which has led to alternative cementing systems being examined. We have investigated the physical, chemical and microstructural properties of a supersulfated cement in order to determine its applicability for use in nuclear waste encapsulation. The hardened supersulfated cement paste appeared to have properties desirable for use in producing encapsulation matrices, but the high powder specific surface resulted in a matrix with high porosity. Ettringite and calcium silicate hydrate were the main phases formed in the hardened cement paste and anhydrite was present in excess. The maximum rate of heat output during hydration of the supersulfated cement paste was slightly higher than that of a 9:1 blastfurnace slag:ordinary Portland cement paste commonly used by the UK nuclear waste processing industry, although the total heat output of the supersulfated cement paste was lower. The pH was also significantly lower in the supersulfated cement paste. Aluminium hydroxide was formed on the surface of aluminium metal encapsulated in the cement paste and ettringite was detected between the aluminium hydroxide and the hardened cement paste.

MOX fuel fabrication: Technical and industrial developments

International Nuclear Information System (INIS)

Lebastard, G.; Bairiot, H.

1990-01-01

The plutonium available in the near future is generally estimated rather precisely on the basis of the reprocessing contracts and the performance of the reprocessing plants. A few years ago, decision makers were convinced that a significant share of this fissile material would be used as the feed material for fast breeder reactors (FBRs) or other advanced reactors. The facts today are that large reprocessing plants are coming into commercial operations: UP3 and soon UP2-800 and THORP, but that FBR deployment is delayed worldwide. As a consequence, large quantities of plutonium will be recycled in light water reactors as mixed oxide (MOX) fuels. MOX fuel technology has been properly demonstrated in the past 25 years. All specific problems have been addressed, efficient fabrication processes and engineering background have been implemented to a level of maturity which makes MOX fuel behaving as well as Uranium fuel. The paper concentrates on todays MOX fabrication expertise and presents the technical and industrial developments prepared by the MOX fuel fabrication industry for this last decade of the century

Hydration rate and strength development of low-heat type portland cement mortar mixed with pozzolanic materials

International Nuclear Information System (INIS)

Matsui, Jun

1998-01-01

Recently, low-heat type Portland cement was specified in Japan Industrial Standards (JIS). Its hydration proceeds slowly. The results of the research so far obtained indicate that slow hydration of cement and mixing of pozzolanic materials with cement make micro-structure of harded cement paste dense and durable. In this study, a blended cement using low-heat type Portland cement and some of pozzolanic materials has been newly developed and its strength property and hydration ratio were checked. The followings are conclusion. (1) Hydration rate of cement paste varies with the replacement ratio of pozzolanic materials. (2) A good liner relationship between strength and total hydration rate of cement paste was observed. (3) A proper replacement ratio of both base-cement and pozzolanic material for manufacturing a blended cement is 50%. (author)

LOW WATER DEMAND CEMENTS - WAY OF EFFICIENT USE OF CLINKER AND MINERAL FILLERS IN CONCRETES

Directory of Open Access Journals (Sweden)

Khokhryakov Oleg Viktorovich

2017-10-01

Full Text Available Subject: the provisions in the updated edition of the technical specifications for cements are analyzed. A trend to decrease the clinker volume in Portland cement due to the wider use of mineral additives, up to 95%, was observed. Research objectives: substantiation of the most complete and efficient use of Portland cement and mineral additives in the composition of low water demand cements. Materials and methods: portland cement, mineral additives and superplasticizer were used as raw materials for obtaining cements of low water demand. The experimental methods comply with the current standards. Results: comparative properties of low water demand cements and cements with mineral additives are presented. The properties of cement-water suspensions of these binders have been studied, and, on their basis, heavy concretes have been made. The results of the grindability of Portland cement and mineral components with a superplasticizer are given. Conclusions: it is shown that the cement of low water demand, in which the advantages of both Portland cement and mineral additives are more fully and efficiently presented, complies with the tendency to decrease the clinker volume to the greatest degree. It is established that the clinker volume index for heavy concrete prepared on low water demand cement is almost four times lower than that for heavy concrete based on common Portland cement.

Nano-Inclusions Applied in Cement-Matrix Composites: A Review

Directory of Open Access Journals (Sweden)

Guillermo Bastos

2016-12-01

Full Text Available Research on cement-based materials is trying to exploit the synergies that nanomaterials can provide. This paper describes the findings reported in the last decade on the improvement of these materials regarding, on the one hand, their mechanical performance and, on the other hand, the new properties they provide. These features are mainly based on the electrical and chemical characteristics of nanomaterials, thus allowing cement-based elements to acquire “smart” functions. In this paper, we provide a quantitative approach to the reinforcements achieved to date. The fundamental concepts of nanoscience are introduced and the need of both sophisticated devices to identify nanostructures and techniques to disperse nanomaterials in the cement paste are also highlighted. Promising results have been obtained, but, in order to turn these advances into commercial products, technical, social and standardisation barriers should be overcome. From the results collected, it can be deduced that nanomaterials are able to reduce the consumption of cement because of their reinforcing effect, as well as to convert cement-based products into electric/thermal sensors or crack repairing materials. The main obstacle to foster the implementation of such applications worldwide is the high cost of their synthesis and dispersion techniques, especially for carbon nanotubes and graphene oxide.

Mechanical properties of Self-Consolidating Concrete incorporating Cement Kiln Dust

OpenAIRE

El-Mohsen, Mostafa Abd; Anwar, Ahmed M.; Adam, Ihab A.

2015-01-01

Self-Consolidating Concrete (SCC) has been widely used in both practical and laboratory applications. Selection of its components and their ratios depends, mainly, on the target mechanical and physical properties recommended by the project consultant. Partial replacement of cement in SCC with cheap available industrial by-product could produce environmentally durable concrete with similar properties of normal concrete. In the current research, SCC was produced by blending Cement Kiln Dust (CK...

Technical executive’s organizational commitment at Malaysian Oil & Gas Industry

OpenAIRE

Firend, A.R; Binti Sofyan, P.

2016-01-01

This paper investigates the levels of organizational commitment among technical executive, identifies factors that influence organizational commitment in the Malaysian oil and gas industry, and examines the impact of organizational commitment on organizational performance. This research was conducted at Malaysia Marine and Heavy Engineering (MMHE). The framework adopted the three component-conceptualization of organizational commitment. Among the findings is that organizational commitment ten...

CONTRIBUTION TO THE STATISTICAL INTERPRETATION OF RAW MATERIALS FOR THE CEMENT INDUSTRY OF SPLIT

Directory of Open Access Journals (Sweden)

Miroslav Matijaca

1990-12-01

Full Text Available Up to the last two decades cement was produced from mari called »tupina« (with about 76% CaCOj which is an ideal mixture for cement production. Due to the quantity decrease of this raw material, cement production went on using the mixture of other members of the flysch series: limestones, marls, clay, loess, sandstones a.o. By the analysis of natural materials the CaCO^ content has mostly been proved. Therefore, knowing the correlation of oxides in mineral raw material is of special significance. The article discusses investigation results of the correlation between CaCO-i and other oxides of the raw material (the paper is published in Croatian.

Design, Explanation, and Evaluation of Training Model Structures Based on Learning Organization--In the Cement Industry with a Nominal Production Capacity of Ten Thousand Tons

Science.gov (United States)

Rahimian, Hamid; Kazemi, Mojtaba; Abbspour, Abbas

2017-01-01

This research aims to determine the effectiveness of training based on learning organization in the staff of cement industry with production capacity over ten thousand tons. The purpose of this study is to propose a training model based on learning organization. For this purpose, the factors of organizational learning were introduced by…

System of lower cogeneration in the cement industry; Sistema de cogeneracion inferior en la industria del cemento

Energy Technology Data Exchange (ETDEWEB)

Romero Paredes, H.; Vazquez, A; Ambriz, J. J.; Fosado, A.; Cedillo, D.; Sanchez, R. [Universidad Autonoma Metropolitana-Iztapalapa (Mexico)

1999-07-01

In this paper present work, the design of a cogeneration system was made, taking advantage of the waste thermal flows in a cement manufacturing industry. The costs by concept of energy sources in the cement industry represent between 30 and 60% of the production costs, reason why any diminution in its consumption, will be reflected considerably in the productivity of the company. In order to determine the available capacity of waste energy and to establish the dimension of the cogeneration system it was decided to initially conduct balances of matter and energy of a cement production train. For the evaluation and numerical simulation a case study of a national plant was taken. The analysis takes only into account the rotary kiln, the pre roaster, the gas cooler or conditioner, the cooler of clinker and the separators or dust recuperators. In this study the electrical mills nor the systems that operate all over the plant have been taken in consideration. The results show that in general a high potential of co-generation exists since in some cases the heat losses can reach up to a 50% of the calorific energy input. The capacity of electrical generation by means of a steam turbine when taking advantage of a fraction (in the order of 60%) the residual heat, can be between 200 and 300 watts per kilogram of clinker produced. In conclusion, when recovering by means of appropriate heat exchangers for each one of the mentioned equipment the wasted energy and a network of heat interchange optimized by means of modern technologies an important part of the electrical energy that a cement mill uses can be generated. The method used has been very attractive and with the possibility of applying it to any cement mill and thus evaluate the potentials of energy co-generation. [Spanish] En el presente trabajo, se realizo el diseno de un sistema de cogeneracion aprovechando las corrientes termicas de desecho en una industria de fabricacion de cemento. Los costos por concepto de

Energy efficiency enhancement in cement factories using expert system

International Nuclear Information System (INIS)

Effatnejad, R.; Jadih, S.

2001-01-01

Full text : In this paper, expert system for energy efficiency in cement industry is presented. Due to the fact that cement manufacturing project in these factories are similar, so in main parts knowing the consumption origins and save potential and existing approaches can be similar. In this method, via expert system software of prolog AH types of energy consumption and investment costs are listed in which method of best first search and innovative search have been used and by forming knowledge base, targeting to get best approaches is presented. The obtained results, regarding the executed limits, will be displayed in the output of program and this program can be given the best decision about energy management in cement factories

Application of ESP for gas cleaning in cement industry--with reference to India.

Science.gov (United States)

Bapat, J D

2001-02-16

Electrostatic precipitators (ESP) are used for gas cleaning in almost every section of cement manufacture. Application of ESP is studied, keeping in view Indian conditions. The characterisation of dust emissions has been done for different units, such as rotary kiln and raw mill, alkali by-pass, clinker cooler, cement and coal mill, in terms of exit gas quantity, temperature, dew point, dust content and particle size. It is seen that all these characteristics have a wide range of variance. The ESP system must effectively deal with these variations. The fundamental analytical expression governing the performance of ESP, i.e. the Deutsch equation, and that for particle migration velocity, were analysed to predict the effect of major operating parameters, namely particle size, temperature and applied voltage. Whereas the migration velocity (and the efficiency) varies directly with the particle size, it is proportional to the square and square root of applied voltage and absolute temperature of the gas, respectively. The increase in efficiency due to temperature is not seen in dc based ESP, perhaps due to more pronounced negative effect on the applied voltage due to the increase in dust resistivity at higher temperatures. The effect of gas and dust characteristics on the collection efficiency of ESP, as seen in the industrial practice, is summarised. Some main process and design improvements effectively dealing with the problem of gas and dust characteristics have been discussed. These are gas conditioning, pulse energization, ESP-fabric filter (FF) combination, improved horizontal flow as well as open top ESP.Generally, gas conditioning entails higher operating and maintenance costs. Pulse energization allows the use of hot gas, besides reducing the dust emission and power consumption. The improved horizontal flow ESP has been successfully used in coal dust cleaning. The open top or vertical flow ESP has a limitation on collection efficiency as it provides for only

Physico-Chemical Studies Involving Incorporation of Radioactive and Industrial Waste In Cement-Epoxy Resin Matrix

International Nuclear Information System (INIS)

Sayed, M.S.; Hafez, N.

1999-01-01

Cement and epoxy resin as chemical additives are proposed to incorporate different types of wastes. The study was extended to prepare different mixtures of cement and epoxy resin in presence of some toxic ions. The studied ions were Cd II, Ni II, Cu II, Fe III, Ce IV, 154+152 Eu, phenol and toluene. The physical, mechanical and leaching properties of the mixtures were studied. The thermal analysis and infrared spectra were also investigated. It was observed that all the studied properties of the epoxy modified cement as a disposal matrix was improved

Design and application of environmentally effective concrete with usage of chrysotile-cement waste

Directory of Open Access Journals (Sweden)

Egorova Lada

2016-01-01

Full Text Available Construction is resource-demanding industry, characterized by a large volume of waste. Particularly chrysotile cement waste obtained both in production and in dismantling over age chrysotile-cement products: corrugated asbestos boards and flat sheets, chrysotile-cement tubes. We propose to use dry chrysotile-cement waste as recycled aggregate for concrete. Based on developed compositions and identified properties of heavy concrete with chrysotile-cement waste introduce this technology to the production of foundation wall blocks. The studies confirmed the possibility of using chrysotile-cement aggregate and fine screening of crushing as a secondary coarse and fine aggregates for concrete with proper quality without increasing the cost of the product. Environmental safety of the obtained products was ensured. The direction for implementation of the research project was proposed.

Performance of portland limestone cements: Cements designed to be more sustainable that include up to 15% limestone addition

Science.gov (United States)

Barrett, Timothy J.

In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested

State-of-the-art of furnace recuperation in the primary metals industry: technical briefing report

Energy Technology Data Exchange (ETDEWEB)

Moore, N.L.

1983-08-01

Existing and emerging recuperator technology is identified, as well as the technical and economic issues in applying such technology. An overview of recuperation and its relevance to the primary metals industry is presented. Design considerations, equipment, and energy and cost savings of five recuperator applications in the primary metals industry are examined. Three applications include a case history of a recent recuperator installation. A cost engineering analysis of recuperator technology is included to ensure that technically feasible engineering projects are also economically attractive business ventures. An overview of emerging recuperation technology is presented.

Industrial processes inventory. Sector 2

International Nuclear Information System (INIS)

1994-01-01

The work objective is to conduct a greenhouse gas emission inventory of the industrial processes in Lebanon for the year 1994. The Lebanese industry has emitted 1924.063 Gg (1.924.063 tons) of Carbon dioxide CO 2 ; 0.0003 Gg (0.3 tons) of carbon monoxide CO; 0.01112 Gg of nitrogen oxide NO; 273.888 tons of non-methane volatile organic compounds and 3.382 Gg (3.382 tons) of sulphur dioxide SO 2 . The cement industry is the major source of CO 2 emissions among the industrial processes in Lebanon. The cement industry is responsible for 76.1% of the total emissions followed by the iron and steel industry which produces 21.68% of the total CO 2 emissions from industrial processes. The NMVOC emissions are mainly produced by the use of asphalt for road paving (98.5% of total emissions by industry) followed by the food and beverage industry (1.2%). The emissions of sulphur dioxide SO 2 come from three industrial sources: the first come from the production of sulphuric acid (69.9% of total industrial emissions), the second from the cement industry (26.4% of total industrial emissions) and the third from the iron and steel mills (3.7% of total industrial emissions). Figures are presented to show the percentage distribution of various industrial sources contributions to CO 2 , NMVOC and SO 2 emissions in Lebanon. Carbon monoxide CO emissions in the industrial sector are very small. The major source is iron and steel mills and the minor source is asphalt-roofing production

Industrial Arts Curriculum Guide in Basic Technical Drafting. Bulletin No. 1686.

Science.gov (United States)

Louisiana State Dept. of Education, Baton Rouge. Div. of Vocational Education.

This curriculum guide contains operational guidelines to help local administrators, teacher educators, and industrial arts teachers in the State of Louisiana determine the extent to which their technical drafting courses are meeting the needs of the youth they serve. It consists of a discussion of course prerequisites, goals, content, and…

Innovation and technical efficiency in Malaysian family manufacturing industries

OpenAIRE

Susila Munisamy; Edward Wong Sek Khin; Chia Zi Fon

2015-01-01

This study investigates the technical efficiency for each industry in the Malaysian manufacturing sector is estimated by using Data Envelopment Analysis (DEA). In order to pursue a balance of innovation between long-term and short-term performance strategy, we integrate the Balance Scorecard (BSC) approach with DEA. Furthermore, this paper looks at the determinants of efficiency using the Tobit regression model. In measuring the level of firms’ efficiency and innovation, the wood and wood b...

Sustainable Nanopozzolan Modified Cement: Characterizations and Morphology of Calcium Silicate Hydrate during Hydration

Directory of Open Access Journals (Sweden)

N. Mohamed Sutan

2015-01-01

Full Text Available There are environmental and sustainable benefits of partially replacing cement with industrial by-products or synthetic materials in cement based products. Since microstructural behaviours of cement based products are the crucial parameters that govern their sustainability and durability, this study investigates the microstructural comparison between two different types of cement replacements as nanopozzolan modified cement (NPMC in cement based product by focusing on the evidence of pozzolanic reactivity in corroboration with physical and mechanical properties. Characterization and morphology techniques using X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR, energy-dispersive X-ray spectroscopy (EDS, and scanning electron microscopy (SEM were carried out to assess the pozzolanic reactivity of cement paste modified with the combination of nano- and micro silica as NPMC in comparison to unmodified cement paste (UCP of 0.5 water to cement ratio (w/c. Results were then substantiated with compressive strength (CS results as mechanical property. Results of this study showed clear evidence of pozzolanicity for all samples with varying reactivity with NPMC being the most reactive.

Compressive strength of different brands of cement (OPC) in province of Sindh

International Nuclear Information System (INIS)

Khaskheli, G.B.; Kumar, A.; Sheikh, A.

2009-01-01

OPC (Ordinary Portland Cement) is the most common type of cement used in construction industry. Three major brands of OPC are normal OPC, SRC (Sulphate Resisting Cement) and SC (Slag Cement). It is seen that the variation in constituents of cement may cause serious effects on the quality of cement. Thus the motivation of this research is to study the basic properties (consistency, setting time, and fineness), compressive strength (cement mortar and concrete cubes) and modulus of elasticity of all the OPC brands (OPC, SRC and SC) manufactured in Sindh. In total 10 cement factories, altogether 21 different brands of cement, were studied in the light of BS and ASTM Code specifications. In total 126 mortar cubes (1:3), 252 concrete cubes (126 for 3000 psi mix design and remaining for 5000 psi) and 126 concrete cylinders (6 for the each brand of cement pertaining to 3000 psi and 5000 psi mix design) were manufactured and tested. Experimental results demonstrated that all the cement brands fulfilled the BS and ASTM Code requirements for (i) basic properties (ii) compressive strength of mortar cubes at 3 and 28 days curing age (iii) compressive strength of concrete cubes at 28 days curing age, and (iv) modulus of elasticity. Some of the cements did not fulfill the BS and ASTM Code requirements for compressive strength of concrete cubes at 7 days curing age. (author)

Environmental Assessment of Different Cement Manufacturing Processes Based on Emergy and Ecological Footprint Analysis

Science.gov (United States)

Due to its high environmental impact and energy intensive production, the cement industry needs to adopt more energy efficient technologies to reduce its demand for fossil fuels and impact on the environment. Bearing in mind that cement is the most widely used material for housin...

Durability of saw-cut joints in plain cement concrete pavements : [technical summary].

Science.gov (United States)

2011-01-01

The main objective of this study was to evaluate factors influencing the durability of the joints in portland cement concrete pavement in the state of Indiana. : The scope of the research included the evaluation of the absorption of water in concrete...

Technical management techniques for identification and control of industrial safety and pollution hazards

Science.gov (United States)

Campbell, R.; Dyer, M. K.; Hoard, E. G.; Little, D. G.; Taylor, A. C.

1972-01-01

Constructive recommendations are suggested for pollution problems from offshore energy resources industries on outer continental shelf. Technical management techniques for pollution identification and control offer possible applications to space engineering and management.

Cermet cements.

Science.gov (United States)

McLean, J W

1990-01-01

Cermet ionomer cements are sintered metal/glass powders, which can be made to react with poly(acids). These new cements are significantly more resistant to abrasion than regular glass ionomer cements and are widely accepted as core build-up materials and lining cements. They can strengthen teeth and provide the clinician with an opportunity to treat early dental caries.

Methodology for quantitative assessment of technical condition in industrial systems

Energy Technology Data Exchange (ETDEWEB)

Steinbach, C [Marintek AS (Norway); Soerli, A [Statoil (Norway)

1999-12-31

As part of the Eureka project Ageing Management a methodology has been developed to assess the technical condition of industrial systems. The first part of the presentation argues for the use of technical condition parameters in the context of maintenance strategies. Thereafter the term `technical condition` is defined more thoroughly as it is used within the project. It is claimed that the technical condition of a system - such as a feed water system of a nuclear power plant, or a water injection system on an oil platform - may be determined by aggregating the condition of its smaller components using a hierarchic approach. The hierarchy has to be defined in co-operation with experienced personnel and reflects the impact of degradation of elements on a lower level to nodes higher in the hierarchy. The impact is divided into five categories with respect to safety, environment, availability, costs and man-hours. To determine the technical condition of the bottom elements of the hierarchy, available data is used from both an on-line condition monitoring system and maintenance history. The second part of the presentation introduces the prototype software tool TeCoMan which utilises the theory and applies it to installations of the participating companies. First results and gained experiences with the method and tool are discussed. (orig.)

Methodology for quantitative assessment of technical condition in industrial systems

Energy Technology Data Exchange (ETDEWEB)

Steinbach, C. [Marintek AS (Norway); Soerli, A. [Statoil (Norway)

1998-12-31

As part of the Eureka project Ageing Management a methodology has been developed to assess the technical condition of industrial systems. The first part of the presentation argues for the use of technical condition parameters in the context of maintenance strategies. Thereafter the term `technical condition` is defined more thoroughly as it is used within the project. It is claimed that the technical condition of a system - such as a feed water system of a nuclear power plant, or a water injection system on an oil platform - may be determined by aggregating the condition of its smaller components using a hierarchic approach. The hierarchy has to be defined in co-operation with experienced personnel and reflects the impact of degradation of elements on a lower level to nodes higher in the hierarchy. The impact is divided into five categories with respect to safety, environment, availability, costs and man-hours. To determine the technical condition of the bottom elements of the hierarchy, available data is used from both an on-line condition monitoring system and maintenance history. The second part of the presentation introduces the prototype software tool TeCoMan which utilises the theory and applies it to installations of the participating companies. First results and gained experiences with the method and tool are discussed. (orig.)

Immobilization of Radioactive Waste in Different Fly Ash Zeolite Cement Blends

International Nuclear Information System (INIS)

Sami, N.M.

2013-01-01

The problem of radioactive waste management has been raised from the beginning use of nuclear energy for different purposes. The rad waste streams produced were sufficient to cause dangerous effects to man and its environment. The ordinary portland cement is the material more extensively used in the technologies of solidification and immobilization of the toxic wastes, low and medium level radioactive wastes. The production of portland cement is one of the most energy-intensive and polluting. The use of high energy in the production causes high emission due to the nature and processes of raw materials. The cement industry is responsible for 7% of the total CO 2 emission. Thus, the cement industry has a crucial role in the global warming. The formation of alite (Ca 3 SiO 5 ), which is the main component of the Portland cement clinker, produces a greater amount of CO 2 emission than the formation of belite (Ca 2 SiO 4 ). The proportion of alite to belite is about 3 in ordinary Portland clinker. Therefore, by decreasing this proportion less CO 2 would be emitted. Furthermore, if industrial byproducts such as fly ash from thermal power station or from incineration of municipal solid wastes have the potential to reduce CO 2 used as raw materials and alternative hydrothermal calcination routes are employed for belite clinker production, CO 2 emission can be strongly reduced or even totally avoided. The availability of fly ash will help in reducing the CO 2 emissions and will also help in resolving, to a great extent, the fly ash disposal problem. This thesis is based on focusing on the possibility of using fly ash as raw materials to prepare low cost innovation matrices for immobilization of radioactive wastes by synthesizing new kind of cement of low consuming energy. The synthesis process is based on the hydrothermal-calcination route of the fly ash without extra additions.

Leaf structural traits of tropical woody species resistant to cement dust.

Science.gov (United States)

Siqueira-Silva, Advanio Inácio; Pereira, Eduardo Gusmão; Modolo, Luzia Valentina; Paiva, Elder Antonio Sousa

2016-08-01

Cement industries located nearby limestone outcrops in Brazil have contributed to the coating of cement dust over native plant species. However, little is known about the extent of the response of tropical woody plants to such environmental pollutant particularly during the first stages of plant development and establishment. This work focused on the investigation of possible alterations in leaf structural and ultrastructural traits of 5-month-old Guazuma ulmifolia Lam. (Malvaceae), 6-month-old Myracrodruon urundeuva Allemão (Anacardiaceae), and 9-month-old Trichilia hirta L. (Meliaceae) challenged superficially with cement dust during new leaf development. Leaf surface of plants, the soil or both (leaf plus soil), were treated (or not) for 60 days, under controlled conditions, with cement dust at 2.5 or 5.0 mg cm(-2). After exposure, no significant structural changes were observed in plant leaves. Also, no plant death was recorded by the end of the experiment. There was also some evidence of localized leaf necrosis in G. ulmifolia and T. hirta, leaf curling in M. urundeuva and T. hirta, and bulges formation on epidermal surface of T. hirta, after cement dust contact with plant shoots. All species studied exhibited stomata obliteration while T. hirta, in particular, presented early leaf abscission, changes in cellular relief, and organization and content of midrib cells. No significant ultrastructural alterations were detected under the experimental conditions studied. Indeed, mesophyll cells presented plastids with intact membrane systems. The high plant survival rates, together with mild morphoanatomic traits alterations in leaves, indicate that G. ulmifolia is more resistant to cement dust pollutant, followed by M. urundeuva and T. hirta. Thus, the three plant species are promising for being used to revegetate areas impacted by cement industries activities.

Design, quality, and quality assurance of solid recovered fuels for the substitution of fossil feedstock in the cement industry.

Science.gov (United States)

Sarc, R; Lorber, K E; Pomberger, R; Rogetzer, M; Sipple, E M

2014-07-01

This paper describes the requirements for the production, quality, and quality assurance of solid recovered fuels (SRF) that are increasingly used in the cement industry. Different aspects have to be considered before using SRF as an alternative fuel. Here, a study on the quality of SRF used in the cement industry is presented. This overview is completed by an investigation of type and properties of input materials used at waste splitting and SRF production plants in Austria. As a simplified classification, SRF can be divided into two classes: a fine, high-calorific SRF for the main burner, or coarser SRF material with low calorific value for secondary firing systems, such as precombustion chambers or similar systems. In the present study, SRFs coming from various sources that fall under these two different waste fuel classes are discussed. Both SRFs are actually fired in the grey clinker kiln of the Holcim (Slovensko) plant in Rohožnik (Slovakia). The fine premium-quality material is used in the main burner and the coarse regular-quality material is fed to a FLS Hotdisc combustion device. In general, the alternative fuels are used instead of their substituted fossil fuels. For this, chemical compositions and other properties of SRF were compared to hard coal as one of the most common conventional fuels in Europe. This approach allows to compare the heavy metal input from traditional and alternative fuels and to comment on the legal requirements on SRF that, at the moment, are under development in Europe. © The Author(s) 2014.

The relationship between technical efficiency and industial concentration: Evidnce from the Indonesian food and beverages industry

NARCIS (Netherlands)

Setiawan, M.; Emvalomatis, G.; Oude Lansink, A.G.J.M.

2012-01-01

This paper investigates the relationship between technical efficiency and industrial concentration in the Indonesian food and beverages sector. Firm-level data obtained from the Indonesian Bureau of Central Statistics (BPS) are used to estimate technical efficiency scores and calculate measures of

Mechanical properties of Self-Consolidating Concrete incorporating Cement Kiln Dust

Directory of Open Access Journals (Sweden)

Mostafa Abd El-Mohsen

2015-04-01

Full Text Available Self-Consolidating Concrete (SCC has been widely used in both practical and laboratory applications. Selection of its components and their ratios depends, mainly, on the target mechanical and physical properties recommended by the project consultant. Partial replacement of cement in SCC with cheap available industrial by-product could produce environmentally durable concrete with similar properties of normal concrete. In the current research, SCC was produced by blending Cement Kiln Dust (CKD with cement in different ratios. Four mixes incorporating cement kiln dust with partial cement replacement of 10%, 20%, 30%, and 40% were produced and compared with a control mix of Normally Vibrated Concrete (NVC. Superplasticizer was used to increase the flow-ability of SCC mixes. The fresh and hardened mechanical properties of all mixes were determined and evaluated. Moreover, time-dependent behavior was investigated for all mixes in terms of drying shrinkage test. The shrinkage strain was measured for all specimens for a period of 120 days. Based on the experimental results, it was found that SCC mixture containing 20% cement replacement of CKD exhibited the highest mechanical strength compared to other SCC mixes and NVC mix as well. It was observed that the volumetric changes of specimens were directly proportional to the increase of the cement replacement ratio.

Study of technical and financial pre-feasibility for the handling and sale, as fuel in cement industries, of petroleum coke produced at a petroleum refinery located in Moin, Limon

International Nuclear Information System (INIS)

Corrales Suarez, Jeffry

2013-01-01

A study of the technical and financial pre-feasibility is realized for the handling, conditioning and sale as fuel in cement industries of petroleum coke, that is produced in the project of extension and modernization of the refinery of RECOPE in Moin, Limon. Daily production has been of 570 metric tons. The market study has determined a demand of approximately 120 000 metric tons in the country and in the region. The total production of coke has been possible place it at national and regional level, due to lack of another producer. The coke is recommended to crush it to decrease the size of the particles for the conditioning, handling and to facilitate their manipulation. Conveyor belts are used for handling on the inside of the refinery. The coke is transported in trucks type tanker on the exterior of the refinery. The moisture content is reduced by dryer vibratory of fluidized bed to 5% of moisture to guarantee a product better quality. The product is stored under roof in ventilated facilities and with appropriate systems of security to minimize the risk of an accident. The fixed capital investment to develop the project has been of USD 3,1 millions and working capital of USD 14,4 millions. The financial evaluation is realized considering two financing models of 70% and without financing. The net present value (NPV) has been of USD -13,0 millions and the desirability index of -6,6 for the model with financing. The model without financing has obtained a NPV of USD -1,9 millions and a desirability index of -1,2. The financial profitability of the project has been very sensitive to the sales price of the coke, to the coke volume of production, to the growth percentage of the sale price and the cost of the raw material for the two models considered. The financial risk analysis is realized by the Monte Carlo method, whereupon is obtained a probability of approximately 34% in that the internal rate of return (IRR) has been higher than the cut rate and of 36% in that

Cement burns: retrospective study of 18 cases and review of the literature.

Science.gov (United States)

Poupon, M; Caye, N; Duteille, F; Pannier, M

2005-11-01

Cement is increasingly used in the construction industry, but the occurrence of cement burns is rarely reported. This retrospective study concerns patients treated for cement burns in our unit between 1997 and 2002. Eighteen patients 18-64 years of age, treated previously in our unit for cement burns, were interviewed by telephone for evaluation. The mean time since treatment was 39 months. Burns were predominantly seen on the lower limbs, and a third occurred during an accident on the job. All deep burns were excised, and 16 patients received grafts. Mean hospital stay was 10 days, and mean sick leave 2 months. Our study indicated that all patients were poorly informed about cement-related risks. Surgical treatment of full-thickness cement burns at diagnosis enables rapid healing with a minimum of sequelae and reduces the high socioeconomic costs resulting from these lesions. This study indicates once again the need to improve preventive measures; which are very often inadequate because of lack of awareness of risks.

Disposal of historically contaminated soil in the cement industry and the evaluation of environmental performance.

Science.gov (United States)

Li, Yeqing; Zhang, Jiang; Miao, Wenjuan; Wang, Huanzhong; Wei, Mao

2015-09-01

Approximately 400000t of DDTs/HCHs-contaminated soil (CS) needed to be co-processed in a cement kiln with a time limitation of 2y. A new pre-processing facility with a "drying, grinding and DDTs/HCHs vaporizing" ability was equipped to meet the technical requirements for processing cement raw meal and the environmental standards for stack emissions. And the bottom of the precalciner with high temperatures >1000°C was chosen as the CS feeding point for co-processing, which has rarely been reported. To assess the environmental performance of CS pre- and co-processing technologies, according to the local regulation, a test burn was performed by independent and accredited institutes systematically for determination of the clinker quality, kiln stack gas emissions and destruction efficiency of the pollutant. The results demonstrated that the clinker was of high quality and not adversely affected by CS co-processing. Stack emissions were all below the limits set by Chinese standards. Particularly, PCDD/PCDF emissions ranged from 0.0023 to 0.0085ngI-TEQNm(-3). The less toxic OCDD was the peak congener for CS co-processing procedure, while the most toxic congeners (i.e. 2,3,7,8-TeCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDD) remained in a minor proportion. Destruction and removal efficiency (DRE) and destruction efficiency (DE) of the kiln system were better than 99.9999% and 99.99%, respectively, at the highest CS feeding rate during normal production. To guarantee the environmental performance of the system the quarterly stack gas emission was also monitored during the whole period. And all of the results can meet the national standards requirements. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental Investigation of Properties of Foam Concrete for Industrial Floors in Testing Field

Science.gov (United States)

Vlcek, Jozef; Drusa, Marian; Scherfel, Walter; Sedlar, Bronislav

2017-12-01

Foam concrete (FC), as a mixture of cement, water, additives and technical foam, is well known for more than 30 years. It is building material with good mechanical properties, low thermal conductivity, simple and even high technological treatment. Foam concrete contains closed void pores, what allows achieving low bulk density and spare of raw materials. Thanks to its properties, it is usable as a replacement of conventional subbase layers of the industrial floors, the transport areas or as a part of the foundation structures of the buildings. Paper presents the preparation of the testing field (physical model) which was created for experimental investigation of the foam concrete subbase layer of the industrial floor in a real scale.

European cement conference and exhibition. Proceedings volume

Energy Technology Data Exchange (ETDEWEB)

McCaffrey, R. (ed.)

2004-07-01

Topics covered various aspects of the European cement industry including trends, market, emissions trading, environment, state-of-the-art technology, kilns and dedusting solutions. Two papers have been abstracted separately. A CD-ROM of the conference papers, including additional papers not in the printed volume, is also available.

Retention of metal-ceramic crowns with contemporary dental cements.

Science.gov (United States)

Johnson, Glen H; Lepe, Xavier; Zhang, Hai; Wataha, John C

2009-09-01

New types of crown and bridge cement are in use by practitioners, and independent studies are needed to assess their effectiveness. The authors conducted a study in three parts (study A, study B, and study C) and to determine how well these new cements retain metal-ceramic crowns. The authors prepared teeth with a 20-degree taper and a 4-millimeter length. They cast high-noble metal-ceramic copings, then fitted and cemented them with a force of 196 newtons. The types of cements they used were zinc phosphate, resin-modified glass ionomer, conventional resin and self-adhesive modified resin. They thermally cycled the cemented copings, then removed them. They recorded the removal force and calculated the stress of dislodgment by using the surface area of each preparation. They used a single-factor analysis of variance to analyze the data (alpha = .05). The mean stresses necessary to remove crowns, in megapascals, were 8.0 for RelyX Luting (3M ESPE, St. Paul, Minn.), 7.3 for RelyX Unicem (3M ESPE), 5.7 for Panavia F (Kuraray America, New York) and 4.0 for Fuji Plus (GC America, Alsip, Ill.) in study A; 8.1 for RelyX Luting, 2.6 for RelyX Luting Plus (3M ESPE) and 2.8 for Fuji CEM (GC America) in study B; and 4.9 for Maxcem (Kerr, Orange, Calif.), 4.0 for BisCem (Bisco, Schaumburg, Ill.), 3.7 for RelyX Unicem Clicker (3M ESPE), 2.9 for iCEM (Heraeus Kulzer, Armonk, N.Y.) and 2.3 for Fleck's Zinc Cement (Keystone Industries, Cherry Hill, N.J.) in study C. Powder-liquid versions of new cements were significantly more retentive than were paste-paste versions of the same cements. The mean value of crown removal stress for the new self-adhesive modified-resin cements varied appreciably among the four cements tested. All cements retained castings as well as or better than did zinc phosphate cement. Powder-liquid versions of cements, although less convenient to mix, may be a better clinical choice when crown retention is an issue. All cements tested will retain castings

Processes and Equipment for the Cementation of Radioactive Waste

International Nuclear Information System (INIS)

Schaefer, S.; Studenski, J.

2012-01-01

In this article a short selection of different cement mixer types provided by NUKEM Technologies is given. The variety stems on one hand from historical development, but more especially from specific customer demands to meet their local and technical requirements. The Slant Batch Mixer is successfully installed in several Waste Treatment Centers (WTC). NUKEM Technologies set up these mixers with necessary auxiliary systems to facilitate all the cementation tasks of a WTC. By the slant design of the mixer a homogeneous intermixing and a rapid and comprehensive emptying is achieved. The High Shear Mixer is a batch mixer producing a thixotropic, fast flowing colloidal cement slurry. NUKEM Technologies uses this cement slurry to bubble-free/ empty space-free grouting of pre-packed solid waste items in container. The High Throughput Continuous Mixer is a continuously operating screw mixer that provides a high throughput. One or more dry components are continuously fed to the mixer where liquid waste or water is added. The High Performance In-Drum Mixer is a combination of planetary mixer with double helical mixer. NUKEM Technologies recently has developed a new High Capacity Mixer (HCM) based on a well proven conventional concrete mixer. The HCM is the successor of the slant mixer and will expend NUKEM Technologies' portfolio of cementation units. (A.C.)

ULTRA-LIGHTWEIGHT CEMENT

International Nuclear Information System (INIS)

Fred Sabins

2001-01-01

The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter

A study on the practicability of highly containing fly ash and silica fume cement

International Nuclear Information System (INIS)

Owada, Hitoshi; Mihara, Morihiro; Iriya, Keishiro; Matsui, Jun

2000-01-01

Cementitious materials have been planed to be used for the geological disposal of high-level radioactive waste and TRU waste. Degrading of host rock and buffer material induced by high pH leachate, however, is pointed out as one of technical issues. The authors have been developing a low alkalinity cement (the pH of the leachate of this cement is about 11) as an enhanced material to reduce the effect of the high pH problem. In this study, the applicability of low alkalinity cement developed to solve this problem was evaluated. The fluidity of the mortar was sufficient to fill the aperture in a structure filled with coarse aggregate. The concrete using the low alkalinity cement was also enough to fill a structure with the reinforcing steel. The compressive strength of a test-piece produced by the JIS method and of a core collected from the trial structure were over 60 MPa. These evaluation results show that developed low alkalinity cement had higher performances in mechanical properties and execution characteristics than JIS ordinary Portland cement. (author)

Hydration study of limestone blended cement in the presence of hazardous wastes containing Cr(VI)

International Nuclear Information System (INIS)

Trezza, M.A.; Ferraiuelo, M.F.

2003-01-01

Considering the increasing use of limestone cement manufacture, the present paper tends to characterize limestone behavior in the presence of Cr(VI). The research reported herein provides information regarding the effect of Cr(VI) from industrial wastes in the limestone cement hydration. The cementitious materials were ordinary Portland cement, as reference, and limestone blended cement. The hydration and physicomechanical properties of cementitious materials and the influence of chromium at an early age were studied with X-ray diffraction (XRD), infrared spectroscopy (FTIR), conductimetric and mechanical tests. Portland cement pastes with the addition of Cr(VI) were examined and leaching behavior with respect to water and acid solution were investigated. This study indicates that Cr(VI) modifies the rate and the components obtained during the cement hydration

The use of by-products from metallurgical and mineral industries as filler in cement-based materials.

Science.gov (United States)

Moosberg, Helena; Lagerblad, Björn; Forssberg, Eric

2003-02-01

This investigation has been made in order to make it possible to increase the use of by-products in cement-based materials. Use of by-products requires a screening procedure that will reliably determine their impact on concrete. A test procedure was developed. The most important properties were considered to be strength development, shrinkage, expansion and workability. The methods used were calorimetry, flow table tests, F-shape measurements, measurements of compressive and flexural strength and shrinkage/expansion measurements. Scanning electron microscopy was used to verify some results. Twelve by-products were collected from Swedish metallurgical and mineral industries and classified according to the test procedure. The investigation showed that the test procedure clearly screened out the materials that can be used in the production of concrete from the unsuitable ones.

Application progress of solid 29Si, 27Al NMR in the research of cement-based materials

International Nuclear Information System (INIS)

Feng Chunhua; Wang Xijian; Li Dongxu

2014-01-01

Background: The solid-state Nuclear Magnetic Resonance (NMR) is an effective method for the research of cement-based materials. Now it focuses on using solid 29 Si and 27 Al NMR to research the hydration structure of the cement-based materials in cement chemistry. Purpose: A theoretical guidance is proposed for solid 29 Si and 27 Al NMR technology used in cement chemistry research. Methods: We reviewed the application of solid 29 Si and 27 Al NMR in the cement-based materials and analyzed the problem among the researches. Results: This paper introduced an fundamental, relevant-conditions and basic parameters of NMR, and studied the technical parameters of solid 29 Si and 27 Ai NMR together with the relationship among the hydration structure of cement based material. Moreover, this paper reviewed the related domestic and overseas achievements in the research of hydration structure of the cement-based materials using solid 29 Si and 27 Al NMR. Conclusion: There were some problems in the research on cement-based materials by technology of solid 29 Si and 27 Al NMR. NMR will promote the Hydration theory of cement-based material greatly. (authors)

Study on Cr(VI) Leaching from Cement and Cement Composites

Science.gov (United States)

Palascakova, Lenka; Kanuchova, Maria

2018-01-01

This paper reports an experimental study on hexavalent chromium leaching from cement samples and cement composites containing silica fume and zeolite additions that were subjected to various leaching agents. The water-soluble Cr(VI) concentrations in cements ranged from 0.2 to 3.2 mg/kg and represented only 1.8% of the total chromium content. The presence of chromium compounds with both chromium oxidation states of III and VI was detected in the cement samples by X-ray photoelectron spectroscopy (XPS). Leaching tests were performed in a Britton-Robinson buffer to simulate natural conditions and showed increased dissolution of Cr(VI) up to 6 mg/kg. The highest amount of leached hexavalent chromium was detected after leaching in HCl. The findings revealed that the leaching of chromium from cements was higher by 55–80% than that from the cement composites. A minimum concentration was observed for all cement samples when studying the relationship between the soluble Cr(VI) and the cement storage time. PMID:29690550

PURIFIED WASTE FCC CATALYST AS A CEMENT REPLACEMENT MATERIAL

Directory of Open Access Journals (Sweden)

Danute Vaiciukyniene

2015-06-01

Full Text Available Zeolites are commonly used in the fluid catalytic cracking process. Zeolite polluted with oil products and became waste after some time used. The quantity of this waste inevitably rises by expanding rapidly oil industry. The composition of these catalysts depends on the manufacturer and on the process that is going to be used. The main factors retarding hydration process of cement systems and modifying them strength are organic compounds impurities in the waste FCC catalyst. The present paper shows the results of using purified waste FCC catalyst (pFCC from Lithuania oil refinery, as Portland cement replacement material. For this purpose, the purification of waste FCC catalyst (FCC samples was treated with hydrogen peroxide. Hydrogen peroxide (H2O2 is one of the most powerful oxidizers known. By acting of waste with H2O2 it can eliminate the aforementioned waste deficiency, and the obtained product becomes one of the most promising ingredients, in new advanced building materials. Hardened cement paste samples with FCC or pFCC were formed. It was observed that the pFCC blended cements developed higher strength, after 28 days, compared to the samples with FCC or reference samples. Typical content of Portland cement substituting does not exceed 30 % of mass of Portland cement in samples. Reducing the consumption of Portland cement with utilizing waste materials is preferred for reasons of environmental protection.

A contribution to the industrial valorization of tannery waste: the case of cement industry; Contribution a la valorisation industrielle des dechets de tanneries: cas de la cimenterie

Energy Technology Data Exchange (ETDEWEB)

Yatribi, A.; Boukhars, L. [Service de l' Environnement, Div. de l' Urbanisme, Province de Kenitra (Morocco); Nejmeddine, A. [Laboratoire d' Ecotoxicologi, Faculte des Sciences Semlalia, Marrakech (Morocco)

2001-04-01

The present work addresses the possibility of valorization of tannery waste incineration ashes in the cement industry. To this end, the impact of the addition of ashes at various percentages (0, 5, 10, 15, 20, 25, 30, 35, 40 and 45 % in mass) on some mechanical and physical parameters of cement was examined: normal consistency (%), the beginning of setting (hr), the end of setting (hr), the hot expansion (mm), the resistances to compression and to bending (N/mm{sup 2}) determined on normalized 4 x 4 x 16 cm samples. The impact of the treatment environment (20 deg C and 100 % of relative humidity RH, 30 deg C and 70 % RH, 45 deg C and 45 % RH) was also taken into consideration. The obtained results reveal that the normal consistency, the beginning and the end of setting vary linearly with the quantity of added ashes. Above an addition of ashes of 30 %, the end of setting exceeds the standards demanding a maximum of 10 hours. Additionally, the results indicate that whatever the environment treatment may be, the resistances to compression and to bending increase with the increase of the sample age; they vary inversely to the amount of ash addition. The results allow to conclude that for an ash addition of 15 % and after an ageing of 30 days, the resistance to compression is higher than 40 N/mm{sup 2}, thus allowing the production of CPA 400 cement. These results also allow to conclude that samples kept in a humid environment give the best resistances to compression and to bending, by comparison with those kept in a dry environment. (authors)

Technical and economic benefits of nuclear techniques in ore processing

International Nuclear Information System (INIS)

1989-08-01

This report is the outcome of an Advisory Group Meeting organized by the Agency and hosted by the Institute of Physics and Nuclear Techniques, the Academy of Mining and Metallurgy in Krakow, Poland. The purpose of the meeting was to assess the technical and economic benefits of applying nuclear techniques in ore processing industry. Nucleonic control systems and nuclear on-line analytical techniques as well as radioisotope tracer tests and their applications in metallic ore-processing, coal production, and cement fabrication were discussed. This report contains a summary and the presentations dealing with nuclear techniques for process control made at this meeting. Using a number of case-histories as examples, it illustrates technical and economic benefits obtainable by the installation of nuclear process control instrumentation. It is expected to be useful for everybody dealing with ore and coal production, but especially for administrative personnel and engineers who plan and implement national development programmes related to mineral resources. Refs, figs and tabs

Technical efficiency and CO2 abatement policies in the Dutch glasshouse industry

NARCIS (Netherlands)

Oude Lansink, A.G.J.M.

2003-01-01

This paper develops a short-run microeconomic simulation model of the Dutch glasshouse industry in order to investigate the relation between technical efficiency and marginal abatement costs of CO2 emission. The model is also used to determine the effects of an emission tax and systems of tradable

Percutaneous sacroplasty with the use of C-arm flat-panel detector CT: technical feasibility and clinical outcome

International Nuclear Information System (INIS)

Kang, Sung Eun; Lee, Joon Woo; Kim, Joo Hyung; Kang, Heung Sik; Park, Kun Woo; Yeom, Jin S.

2011-01-01

Sacroplasty for sacral insufficiency fractures (SIFs) has been performed mostly under computed tomography (CT) or fluoroscopy guidance. The purposes of this study are to describe technical tips and clinical outcomes of sacroplasty under C-arm flat panel detector CT (C-arm CT) guidance, and to compare the cement distributions shown on C-arm CT with those on multi-detector CT (MDCT). This study consisted of patients who underwent sacroplasty for SIF using C-arm CT from May 2006 to May 2009. Technical success was assessed in terms of cement filling and leakage. Clinical outcome was assessed at short-term (less than 1 month) and long-term (more than 1 month) follow-up using a four-grade patient satisfaction scale: poor, fair, good, and excellent. After sacroplasty, all patients underwent MDCT and three radiologists compared MDCT images with C-arm CT images in consensus, focusing on the cement distribution and cement leakage. Sacroplasties were performed on both sacral alae in all 8 patients (male:female = 2:6, mean age = 76.9, range = 63-82). The technical success rate was 100%. At short-term follow up, 6 patients (87.5%) reported significant improvement. Five patients (62.5%) were available for long-term follow-up and all 5 patients reported a reduced pain and an improved ability to ambulate. Using MDCT as the standard of reference, the cement distribution was visualized equally well by C-arm CT. Sacroplasty under C-arm CT showed excellent technical success and good clinical outcome. There was an excellent correlation between C-arm CT and MDCT in evaluating cement distribution and cement leakage. (orig.)

Percutaneous sacroplasty with the use of C-arm flat-panel detector CT: technical feasibility and clinical outcome

Energy Technology Data Exchange (ETDEWEB)

Kang, Sung Eun; Lee, Joon Woo; Kim, Joo Hyung; Kang, Heung Sik [Seoul National University Bundang Hospital, Department of Radiology, Gyeonggi-do (Korea, Republic of); Park, Kun Woo; Yeom, Jin S. [Seoul National University Bundang Hospital, Department of Orthopaedic Surgery, Gyeonggi-do (Korea, Republic of)

2011-04-15

Sacroplasty for sacral insufficiency fractures (SIFs) has been performed mostly under computed tomography (CT) or fluoroscopy guidance. The purposes of this study are to describe technical tips and clinical outcomes of sacroplasty under C-arm flat panel detector CT (C-arm CT) guidance, and to compare the cement distributions shown on C-arm CT with those on multi-detector CT (MDCT). This study consisted of patients who underwent sacroplasty for SIF using C-arm CT from May 2006 to May 2009. Technical success was assessed in terms of cement filling and leakage. Clinical outcome was assessed at short-term (less than 1 month) and long-term (more than 1 month) follow-up using a four-grade patient satisfaction scale: poor, fair, good, and excellent. After sacroplasty, all patients underwent MDCT and three radiologists compared MDCT images with C-arm CT images in consensus, focusing on the cement distribution and cement leakage. Sacroplasties were performed on both sacral alae in all 8 patients (male:female = 2:6, mean age = 76.9, range = 63-82). The technical success rate was 100%. At short-term follow up, 6 patients (87.5%) reported significant improvement. Five patients (62.5%) were available for long-term follow-up and all 5 patients reported a reduced pain and an improved ability to ambulate. Using MDCT as the standard of reference, the cement distribution was visualized equally well by C-arm CT. Sacroplasty under C-arm CT showed excellent technical success and good clinical outcome. There was an excellent correlation between C-arm CT and MDCT in evaluating cement distribution and cement leakage. (orig.)

Cement-in-cement acetabular revision with a constrained tripolar component.

Science.gov (United States)

Leonidou, Andreas; Pagkalos, Joseph; Luscombe, Jonathan

2012-02-17

Dislocation of a total hip replacement (THR) is common following total hip arthroplasty (THA). When nonoperative management fails to maintain reduction, revision surgery is considered. The use of constrained acetabular liners has been extensively described. Complete removal of the old cement mantle during revision THA can be challenging and is associated with significant complications. Cement-in-cement revision is an established technique. However, the available clinical and experimental studies focus on femoral stem revision. The purpose of this study was to present a case of cement-in-cement acetabular revision with a constrained component for recurrent dislocations and to investigate the current best evidence for this technique. This article describes the case of a 74-year-old woman who underwent revision of a Charnley THR for recurrent low-energy dislocations. A tripolar constrained acetabular component was cemented over the primary cement mantle following removal of the original liner by reaming, roughening the surface, and thoroughly irrigating and drying the primary cement. Clinical and radiological results were good, with the Oxford Hip Score improving from 11 preoperatively to 24 at 6 months postoperatively. The good short-term results of this case and the current clinical and biomechanical data encourage the use of the cement-in-cement technique for acetabular revision. Careful irrigation, drying, and roughening of the primary surface are necessary. Copyright 2012, SLACK Incorporated.

Utilization of flotation wastes of copper slag as raw material in cement production

International Nuclear Information System (INIS)

Alp, I.; Deveci, H.; Suenguen, H.

2008-01-01

Copper slag wastes, even if treated via processes such as flotation for metal recovery, still contain heavy metals with hazardous properties posing environmental risks for disposal. This study reports the potential use of flotation waste of a copper slag (FWCS) as iron source in the production of Portland cement clinker. The FWCS appears a suitable raw material as iron source containing >59% Fe 2 O 3 mainly in the form of fayalite (Fe 2 SiO 4 ) and magnetite (Fe 3 O 4 ). The clinker products obtained using the FWCS from the industrial scale trial operations over a 4-month period were characterised for the conformity of its chemical composition and the physico-mechanical performance of the resultant cement products was evaluated. The data collected for the clinker products produced using an iron ore, which is currently used as the cement raw material were also included for comparison. The results have shown that the chemical compositions of all the clinker products including those of FWCS are typical of a Portland cement clinker. The mechanical performance of the standard mortars prepared from the FWCS clinkers were found to be similar to those from the iron ore clinkers with the desired specifications for the industrial cements e.g. CEM I type cements. Furthermore, the leachability tests (TCLP and SPLP) have revealed that the mortar samples obtained from the FWCS clinkers present no environmental problems while the FWCS could act as the potential source of heavy metal contamination. These findings suggest that flotation wastes of copper slag (FWCS) can be readily utilised as cement raw material due to its availability in large quantities at low cost with the further significant benefits for waste management/environmental practices of the FWCS and the reduced production and processing costs for cement raw materials

Utilization of flotation wastes of copper slag as raw material in cement production.

Science.gov (United States)

Alp, I; Deveci, H; Süngün, H

2008-11-30

Copper slag wastes, even if treated via processes such as flotation for metal recovery, still contain heavy metals with hazardous properties posing environmental risks for disposal. This study reports the potential use of flotation waste of a copper slag (FWCS) as iron source in the production of Portland cement clinker. The FWCS appears a suitable raw material as iron source containing >59% Fe(2)O(3) mainly in the form of fayalite (Fe(2)SiO(4)) and magnetite (Fe(3)O(4)). The clinker products obtained using the FWCS from the industrial scale trial operations over a 4-month period were characterised for the conformity of its chemical composition and the physico-mechanical performance of the resultant cement products was evaluated. The data collected for the clinker products produced using an iron ore, which is currently used as the cement raw material were also included for comparison. The results have shown that the chemical compositions of all the clinker products including those of FWCS are typical of a Portland cement clinker. The mechanical performance of the standard mortars prepared from the FWCS clinkers were found to be similar to those from the iron ore clinkers with the desired specifications for the industrial cements e.g. CEM I type cements. Furthermore, the leachability tests (TCLP and SPLP) have revealed that the mortar samples obtained from the FWCS clinkers present no environmental problems while the FWCS could act as the potential source of heavy metal contamination. These findings suggest that flotation wastes of copper slag (FWCS) can be readily utilised as cement raw material due to its availability in large quantities at low cost with the further significant benefits for waste management/environmental practices of the FWCS and the reduced production and processing costs for cement raw materials.

ULTRA-LIGHTWEIGHT CEMENT

International Nuclear Information System (INIS)

Fred Sabins

2001-01-01

The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Issues, Task 2: Review Russian Ultra-Lightweight Cement Literature, Task 3: Test Ultra-Lightweight Cements, and Task 8: Develop Field ULHS Cement Blending and Mixing Techniques. Results reported this quarter include: preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; summary of pertinent information from Russian ultra-lightweight cement literature review; laboratory tests comparing ULHS slurries to foamed slurries and sodium silicate slurries for two different applications; and initial laboratory studies with ULHS in preparation for a field job

A technical analysis for cogeneration systems with potential applications in twelve California industrial plants. [energy saving heat-electricity utility systems

Science.gov (United States)

Moretti, V. C.; Davis, H. S.; Slonski, M. L.

1978-01-01

In a study sponsored by the State of California Energy Resources Conservation and Development Commission, 12 industrial plants in five utility districts were surveyed to assess the potential applications of the cogeneration of heat and electricity in California industry. Thermodynamic calculations were made for each plant in determining the energy required to meet the existing electrical and steam demands. The present systems were then compared to conceptual cogeneration systems specified for each plant. Overall energy savings were determined for the cogeneration applications. Steam and gas turbine topping cycle systems were considered as well as bottoming cycle systems. Types of industries studied were: pulp and paper, timber, cement, petroleum refining, enhanced oil recovery, foods processing, steel and glass

The role of cement to be expected in radioactive waste disposal system. 2. From the standpoint of materials design

International Nuclear Information System (INIS)

Tanaka, Satoru; Nagasaki, Shinya; Ohe, Toshiaki

2000-01-01

Cement materials are used at various fields because of their mechanical properties, and then a large construction without using the cement materials is impossible to suppose. For disposal of radioactive wastes, it is expected to use the cement materials for a main constitution material of artificial barrier materials such as construction materials for a disposal facility, wastes container, solidification materials for wastes, and so forth, and in fact, they are used for cement solidified matters, concrete pit as a landfill apparatus, and so forth at the Low Level Radioactive Wastes Storage Center situated in Rokkasho-mura, Aomori prefecture. For their disposal, as cement materials are expected for their property on transfer control of radioactive nuclides such as water stoppage, pH buffering of circumferential groundwater, and transfer retarding, except their mechanical properties, it must be quantitatively investigated how they change with time and if their change forms any problem on safety, because a time to consider their soundness on mechanics or nuclide conservation becomes long term such as for more than hundreds years. Under consideration on disposal and technical trends of radioactive wastes in- and out of-Japan described in previous report, after showing on direction of investigation required to make the cement materials function as an artificial material in disposal of radioactive wastes and on technical trends to it, here was summarized on positioning of studies on cement in the disposal business. (G.K.)

Identifying improvement potentials in cement production with life cycle assessment.

Science.gov (United States)

Boesch, Michael Elias; Hellweg, Stefanie

2010-12-01

Cement production is an environmentally relevant process responsible for 5% of total anthropogenic carbon dioxide emissions and 7% of industrial fuel use. In this study, life cycle assessment is used to evaluate improvement potentials in the cement production process in Europe and the USA. With a current fuel substitution rate of 18% in Europe and 11% in the USA, both regions have a substantial potential to reduce greenhouse gas emissions and save virgin resources by further increasing the coprocessing of waste fuels. Upgrading production technology would be particularly effective in the USA where many kiln systems with very low energy efficiency are still in operation. Using best available technology and a thermal substitution rate of 50% for fuels, greenhouse gas emissions could be reduced by 9% for Europe and 18% for the USA per tonne of cement. Since clinker production is the dominant pollution producing step in cement production, the substitution of clinker with mineral components such as ground granulated blast furnace slag or fly ash is an efficient measure to reduce the environmental impact. Blended cements exhibit substantially lower environmental footprints than Portland cement, even if the substitutes feature lower grindability and require additional drying and large transport distances. The highest savings in CO(2) emissions and resource consumption are achieved with a combination of measures in clinker production and cement blending.

Glass-making furnaces, cement kilns and baking ovens

Energy Technology Data Exchange (ETDEWEB)

1989-01-01

Possible areas for future strategic R and D within the European Community in the cement, glass and bake industries are identified based upon the current scenario of R and D in process industries and following views of main industries and research experts. Priority topics for R and D should include advanced flow modelling, the implementation of control strategies and expert systems and the development of on-line sensors. Fundamental research in some areas, such as advanced diagnostic techniques and sensor systems and modelling of two-phase and pollutant formation, is considered of primary importance.

Sulfur polymer cement, a solidification and stabilization agent for hazardous and radioactive wastes

International Nuclear Information System (INIS)

Darnell, G.R.

1992-01-01

Hydraulic cements have been the primary radioactive waste stabilization agents in the United States for 50 years. Twelve years ago, Brookhaven National Laboratory was funded by the Department of Energy's Defense Low-Level Waste Management Program to test and develop sulfur polymer cement (SPC). It has stabilized routine wastes as well as some troublesome wastes with high waste-to-agent ratios. The Department of Energy's Hazardous Waste Remedial Action Program joined the effort by providing funding for testing and developing sulfur polymer cement as a hazardous-waste stabilization agent. Sulfur polymer cement has passed all the laboratory scale tests required by the US Environmental Protection Agency and US Nuclear Regulatory Commission. Two decades of tests by the US Bureau of Mines and private concrete contractors indicate this agent is likely to exceed other agents in longevity. This bulletin provides technical data from pertinent tests conducted by these various entities

Lime kiln dust as a potential raw material in portland cement manufacturing

Science.gov (United States)

Miller, M. Michael; Callaghan, Robert M.

2004-01-01

In the United States, the manufacture of portland cement involves burning in a rotary kiln a finely ground proportional mix of raw materials. The raw material mix provides the required chemical combination of calcium, silicon, aluminum, iron, and small amounts of other ingredients. The majority of calcium is supplied in the form of calcium carbonate usually from limestone. Other sources including waste materials or byproducts from other industries can be used to supply calcium (or lime, CaO), provided they have sufficiently high CaO content, have low magnesia content (less than 5 percent), and are competitive with limestone in terms of cost and adequacy of supply. In the United States, the lime industry produces large amounts of lime kiln dust (LKD), which is collected by dust control systems. This LKD may be a supplemental source of calcium for cement plants, if the lime and cement plants are located near enough to each other to make the arrangement economical.

Physical, chemical and radioactive characterization of co-products from titanum dioxide industry for valorization in the cement industry; Caracterizacion fisico-quimica y radiactiva de los sub-productos provenientes de la industria de dioxido de titanio para su valorizacion en la industria del cemento: implicaciones radiologicas.

Energy Technology Data Exchange (ETDEWEB)

Gazquez, M.J.; Mantero, J.; Bolivar, J.P.; Garcia-Tenorio, R.; Vaca, F.

2011-07-01

The present study was conducted to characterize the raw materials (ilmenite and slag), waste (red gypsum) and several co-products (sulphate monohydrate and sulphate heptahydrated) form the titanum dioxide industry in relation to their elemental composition (major, minor and trace elements), granulometry, mineralogy, microscopic morphology, physical composition and radioactive content in order to apply this knowledge in the valorization of the co-products in the fields sucha as construction, civil engineering, etc. In particular, the main properties of cements produced with different proportions of red gypsum were studied, and the obtained improvements, in relation to Ordinary Portland Cements (OPC) were evaluated. It was also demonstrated that the levels of pollutants and the radioactive content in the produced RG cements, remain within the regulated safety limits. (Author). 38 refs.

Physical, chemical and radioactive characterization of co-products from titanium dioxide industry for valorization in the cement industry; Caracterizacion fisico-quimica y radiactiva de los sub-productos provenientes de la industria de dioxido de titanio para su valorizacion en la industria del cemento: implicaciones radiologicas.

Energy Technology Data Exchange (ETDEWEB)

Gazquez, M.J.; Mantero, J.; Bolivar, J.P.; Garcia-Tenorio, R.; Vaca, F.

2011-07-01

The present study was conducted to characterize the raw materials (ilmenite and slag), waste (red gypsum) and several co-products (sulphate monohydrate and sulphate heptahydrated) form the titanium dioxide industry in relation to their elemental composition (major, minor and trace elements), granulometry, mineralogy, microscopic morphology, physical composition and radioactive content in order to apply this knowledge in the valorization of the co-products in the fields such a as construction, civil engineering, etc. In particular, the main properties of cements produced with different proportions of red gypsum were studied, and the obtained improvements, in relation to Ordinary Portland Cements (OPC) were evaluated. It was also demonstrated that the levels of pollutants and the radioactive content in the produced RG cements, remain within the regulated safety limits. (Author). 38 refs.

Fabrication of Phosphate Cement with High Integrity

International Nuclear Information System (INIS)

Yang, Jae Hwan; Lee, Chang Hwa; Heo, Cheol Min; Jeon, Min Ku; Kang, Kweon Ho

2011-01-01

As the development of industrial society has accelerated, hazardous wastes are generated as well. According to the 1986 statistics of U.S.A, each person made 40 tons of waste in America that year. Treatment of radioactive waste is one of the most important and serious problems related to waste treatments, because its radioactivity and decaying heat have harmful effects to human and environment for a long time. Nuclear developed countries have used conventional method of treatment such as vitrification or cementation in order to stabilize and solidify radioactive waste. Although the former guarantees the formation of high leaching resistant and durable waste form, it requires several hundred (or even more than one thousand) temperature to melt glass frit. This process generates secondary waste volatilized, as well as being non-economical. Cement technology played a role of immobilizing low and middle class wastes. It has advantages of low temperature setting, low cost, easy process, etc. The alkalinity of ordinary cement, however, constrains the utility of cement to the solidification of alkaline waste. In addition, leachability and mechanical strength of cements are not quite appropriate for the stabilization of high level waste. In this regard, chemically bonded phosphate cement(CBPC), which sets by an acid-base reaction, is a potentially expectable material for immobilization of radioactive waste. CBPC not only sets at room temperature, but also encapsulates various isotopes chemically. The performance of CBPC can be enhanced by the addition of fly ash, sand, wollastonite, etc. This study aims at fabricating the CBPC containing fly ash with high integrity. Morphology, microstructure, and compressive strength are evaluated using SEM, and digital compressing machine

Radionuclide and metal sorption on cement and concrete

CERN Document Server

Ochs, Michael; Wang, Lian

2016-01-01

Cementitious materials are being widely used as solidification/stabilisation and barrier materials for a variety of chemical and radioactive wastes, primarily due to their favourable retention properties for metals, radionuclides and other contaminants. The retention properties result from various mineral phases in hydrated cement that possess a high density and diversity of reactive sites for the fixation of contaminants through a variety of sorption and incorporation reactions. This book presents a state of the art review and critical evaluation of the type and magnitude of the various sorption and incorporation processes in hydrated cement systems for twenty-five elements relevant for a broad range of radioactive and industrial wastes. Effects of cement evolution or ageing on sorption/incorporation processes are explicitly evaluated and quantified. While the immobilisation of contaminants by mixing-in during hydration is not explicitly addressed, the underlying chemical processes are similar. A quantitativ...

Self-healing phenomena in cement-based materials state-of-the-art report of RILEM Technical Committee 221-SHC Self-Healing Phenomena in Cement-Based Materials

CERN Document Server

Tittelboom, Kim; Belie, Nele; Schlangen, Erik

2013-01-01

Self-healing materials are man-made materials which have the built-in capability to repair damage. Failure in materials is often caused by the occurrence of small microcracks throughout the material. In self-healing materials phenomena are triggered to counteract these microcracks. These processes are ideally triggered by the occurrence of damage itself. Thus far, the self-healing capacity of cement-based materials has been considered as something "extra". This could be called passive self-healing, since it was not a designed feature of the material, but an inherent property of it. Centuries-old buildings have been said to have survived these centuries because of the inherent self-healing capacity of the binders used for cementing building blocks together. In this State-of-the-Art Report a closer look is taken at self-healing phenomena in cement-based materials. It is shown what options are available to design for this effect rather than have it occur as a "coincidental extra".

A Twofold Comparison between Dual Cure Resin Modified Cement and Glass Ionomer Cement for Orthodontic Band Cementation.

Science.gov (United States)

Attar, Hanaa El; Elhiny, Omnia; Salem, Ghada; Abdelrahman, Ahmed; Attia, Mazen

2016-12-15

To test the solubility of dual cure resin modified resin cement in a food simulating solution and the shear bond strength compared to conventional Glass ionomer cement. The materials tested were self-adhesive dual cure resin modified cement and Glass Ionomer (GIC). Twenty Teflon moulds were divided into two groups of tens. The first group was injected and packed with the modified resin cement, the second group was packed with GIC. To test the solubility, each mould was weighed before and after being placed in an analytical reagent for 30 days. The solubility was measured as the difference between the initial and final drying mass. To measure the Shear bond strength, 20 freshly extracted wisdom teeth were equally divided into two groups and embedded in self-cure acrylic resin. Four mm sections of stainless steel bands were cemented to the exposed buccal surfaces of teeth under a constant load of 500 g. Shear bond strength was measured using a computer controlled materials testing machine and the load required to deband the samples was recorded in Newtons. GIC showed significantly higher mean weight loss and an insignificant lower Shear bond strength, compared to dual cure resin Cement. It was found that dual cure resin modified cement was less soluble than glass ionomer cement and of comparable bond strength rendering it more useful clinically for orthodontic band cementation.

Characterization of cement and bitumen waste forms containing simulated low-level waste incinerator ash

International Nuclear Information System (INIS)

Westsik, J.H. Jr.

1984-08-01

Incinerator ash from the combustion of general trash and ion exchange resins was immobilized in cement and bitumen. Tests were conducted on the resulting waste forms to provide a data base for the acceptability of actual low-level waste forms. The testing was done in accordance with the US Nuclear Regulatory Commission Technical Position on Waste Form. Bitumen had a measured compressive strength of 130 psi and a leachability index of 13 as measured with the ANS 16.1 leach test procedure. Cement demonstrated a compressive strength of 1400 psi and a leachability index of 7. Both waste forms easily exceed the minimum compressive strength of 50 psi and leachability index of 6 specified in the Technical Position. Irradiation to 10 8 Rad and exposure to 31 thermal cycles ranging from +60 0 ) to -30 0 C did not significantly impact these properties. Neither waste form supported bacterial or fungal growth as measured with ASTM G21 and G22 procedures. However, there is some indication of biodegradation due to co-metabolic processes. Concentration of organic complexants in leachates of the ash, cement and bitumen were too low to significantly affect the release of radionuclides from the waste forms. Neither bitumen nor cement containing incinerator ash caused any corrosion or degradation of potential container materials including steel, polyethylene and fiberglass. However, moist ash did cause corrosion of the steel

Combustion of solid alternative fuels in the cement kiln burner

DEFF Research Database (Denmark)

Nørskov, Linda Kaare

In the cement industry there is an increasing environmental and financial motivation for substituting conventional fossil fuels with alternative fuels, being biomass or waste derived fuels. However, the introduction of alternative fuels may influence emissions, cement product quality, process...... stability, and process efficiency. Alternative fuel substitution in the calciner unit has reached close to 100% at many cement plants and to further increase the use of alternative fuels rotary kiln substitution must be enhanced. At present, limited systematic knowledge of the alternative fuel combustion...... properties and the influence on the flame formation is available. In this project a scientific approach to increase the fundamental understanding of alternative fuel conversion in the rotary kiln burner is employed through literature studies, experimental combustion characterisation studies, combustion...

The mechanical effect of the existing cement mantle on the in-cement femoral revision.

LENUS (Irish Health Repository)

Keeling, Parnell

2012-08-01

Cement-in-cement revision hip arthroplasty is an increasingly popular technique to replace a loose femoral stem which retains much of the original cement mantle. However, some concern exists regarding the retention of the existing fatigued and aged cement in such cement-in-cement revisions. This study investigates whether leaving an existing fatigued and aged cement mantle degrades the mechanical performance of a cement-in-cement revision construct.

Development of road soil cement compositions modified with complex additive based on polycarboxylic ether

Science.gov (United States)

Bulanov, P. E.; Vdovin, E. A.; Mavliev, L. F.; Kuznetsov, D. A.

2018-03-01

The paper is focused on the research results of the main physical and technical properties of the cement-stabilized polymineral clay modified with a complex hydrophobic plasticizer based on polycarboxylate and octyltriethoxysilane ethers. A graphical result interpretation of the mathematic model which shows the influence of the complex hydrophobic plasticizer components on the cement-stabilized polymineral clay, containing more than 85% of relict minerals, has been designed. The research significance for the building sector lies in the fact that applying a complex hydrophobic plasticizer provides increasing the compressive strength of the cement-stabilized polymineral clay up to 102%, the tensile bending strength – up to 88%, the freeze-thaw resistance – up to 114%.

The Role of Vocational and Technical Education in the Industrialization of Malaysia.

Science.gov (United States)

Mustapha, Ramlee B.

The Industrialized Needs study identified the perceptions of Malaysian educators and employers regarding the role of vocational and technical education (VTE) in the economic development of Malaysia. The first survey used a random sample of 300 (276 responses) from the population of 4,316 VTE educators in public VT schools and polytechnics in…

Polymer-Cement Composites with Self-Healing Ability for Geothermal and Fossil Energy Applications

Energy Technology Data Exchange (ETDEWEB)

Childers, M. Ian; Nguyen, Manh-Thuong; Rod, Kenton A.; Koech, Phillip K.; Um, Wooyong; Chun, Jaehun; Glezakou, Vassiliki-Alexandra; Linn, Diana; Roosendaal, Timothy J.; Wietsma, Thomas W.; Huerta, Nicolas John; Kutchko, Barbara G.; Fernandez, Carlos A.

2017-05-18

Sealing of wellbores in geothermal and tight oil/gas reservoirs by filling the annulus with cement is a well-established practice. Failure of the cement as a result of physical and/or chemical stress is a common problem with serious environmental and financial consequences. Numerous alternative cement blends have been proposed for the oil and gas industry. Most of these possess poor mechanical properties, or are not designed to work in high temperature environments. This work reports on a novel polymer-cement composite with remarkable self-healing ability that maintains the required properties of typical wellbore cements and may be stable at most geothermal temperatures. We combine for the first time experimental analysis of physical and chemical properties with density functional theory simulations to evaluate cement performance. The thermal stability and mechanical strength are attributed to the formation of a number of chemical interactions between the polymer and cement matrix including covalent bonds, hydrogen bonding, and van der Waals interactions. Self-healing was demonstrated by sealing fractures with 0.3–0.5 mm apertures, 2 orders of magnitude larger than typical wellbore fractures. This polymer-cement composite represents a major advance in wellbore cementing that could improve the environmental safety and economics of enhanced geothermal energy and tight oil/gas production.

Energy conservation and dust production in wet rotary cement kilns

Energy Technology Data Exchange (ETDEWEB)

Sell, N J; Fischbach, F A

1976-12-01

Energy conservation is currently a major concern of the cement industry. A comparison of data supplied by the U.S. Federal Energy Administration with that gathered in an extensive private study incorporating 29 wet cement plants indicates that a significant reduction of the energy consumed can be accomplished by decreasing the amount of dust generated in the process. Energy saving of 8 percent through dust suppression appears possible by increasing the slurry moisture and by using hammermills rather than impactors as the crushing technique.

Factors affecting bond cement across casing leak zones in oil and gas wells

Energy Technology Data Exchange (ETDEWEB)

Nasr, Mohamed; Edbeib, Said [Al-Fateh University, Tripoli (Libyan Arab Jamahiriya). Dept. of Petroleum Engineering

2004-07-01

Casing leaks have been a major concern to the oil industry because of their effect on lowering the production rate in many oil and gas wells. The leaks are the result of deterioration of the casing in the well, which is caused by severe corrosion due to the contact of the casing with high salinity foreign fluid. The objective of this study is to determine the factors influencing the mechanical properties of the hardened cement opposite the casing leak zones. This study is conducted by laboratory measurements of the compressive strength of the hardened cement when the cement slurry was mixed with different percentages of formation water and different concentrations of different cement additives. The results of this study indicate that the compressive strength readings obtained from the cement bond log and the cement evaluation tool against the casing leak zones are lower than those readings recorded in adjacent formations. The low cement compressive strength values observed across casing leak zones are due to the contamination of the cement with saline water present in these formations which, in turn, effects the hardening properties of the cement. The experimental results indicated that the salinity of the formation water when mixed with the cement slurry in the presence of cement additives, decreased the compressive strength of the bond cement and also decreased the thickening time of the cement slurry. It is concluded that casing leaks found in many wells observed in oil fields in Libya were due to the mixing of the cement with high salinity formation water present in the lost circulation zones. The high water salinity in these zones effects the setting time of the cement slurry which, therefore, decreased the hardening properties of the bond cement and caused cracks and channels in the hardened cement across lost circulation zones. (author)

Mechanisms and modelling of waste-cement and cement-host rock interactions

Science.gov (United States)

2017-06-01

Safe and sustainable disposal of hazardous and radioactive waste is a major concern in today's industrial societies. The hazardous waste forms originate from residues of thermal treatment of waste, fossil fuel combustion and ferrous/non-ferrous metal smelting being the most important ones in terms of waste production. Low- and intermediate-level radioactive waste is produced in the course of nuclear applications in research and energy production. For both waste forms encapsulation in alkaline, cement-based matrices is considered to ensure long-term safe disposal. Cementitious materials are in routine use as industrial materials and have mainly been studied with respect to their evolution over a typical service life of several decades. Use of these materials in waste management applications, however, requires assessments of their performance over much longer time periods on the order of thousands to several ten thousands of years.

Copper-promoted cementation of antimony in hydrochloric acid system: A green protocol

Energy Technology Data Exchange (ETDEWEB)

Wu, Lian-Kui; Li, Ying-Ying; Cao, Hua-Zhen; Zheng, Guo-Qu, E-mail: zhenggq@zjut.edu.cn

2015-12-15

Highlights: • Antimony can be efficiently removed by cementation with copper powder. • Cemented antimony is in the form of Cu{sub 2}Sb. • Consumed copper powder is transformed to CuCl. • The cementation is a chemically controlled step. • No toxic stibine generates during the cementation process. - Abstract: A new method of recovering antimony in hydrochloric acid system by cementation with copper powder was proposed and carried out at laboratory scale. Thermodynamic analysis and cyclic voltammetry test were conducted to study the cementation process. This is a novel antimony removal technology and quite meets the requirements of green chemistry. The main cement product Cu{sub 2}Sb is a promising anodic material for lithium and sodium ion battery. And nearly all consumed copper powder are transformed into CuCl which is an important industrial material. The effect of reaction temperature, stoichiometric ratio of Cu to Sb(III), stirring rate and concentration of HCl on the cementation efficiency of antimony were investigated in detail. Optimized cementation condition is obtained at 60 °C for 120 min and stirring rate of 600 rpm with Cu/Sb(III) stoichiometric ratio of 6 in 3 mol L{sup −1} HCl. At this time, nearly all antimony can be removed by copper powder and the cementation efficiency is over 99%. The structure and morphologies of the cement products were characterized by X-ray diffraction and scanning electron microscopy, respectively. Results show that the reaction temperature has little influence on the morphology of the cement products which consist of particles with various sizes. The activation energy of the cementation antimony on copper is 37.75 kJ mol{sup −1}, indicating a chemically controlled step. Inductively coupled plasma mass spectrometry results show that no stibine generates during the cementation process.

Respiratory tract mortality in cement workers: a proportionate mortality study

Science.gov (United States)

2012-01-01

Background The evidence regarding the association between lung cancer and occupational exposure to cement is controversial. This study investigated causes of deaths from cancer of respiratory tract among cement workers. Methods The deaths of the Greek Cement Workers Compensation Scheme were analyzed covering the period 1969-1998. All respiratory, lung, laryngeal and urinary bladder cancer proportionate mortality were calculated for cement production, maintenance, and office workers in the cement industry. Mortality from urinary bladder cancer was used as an indirect indicator of the confounding effect of smoking. Results Mortality from all respiratory cancer was significantly increased in cement production workers (PMR = 1.91; 95% CI 1.54 to 2.33). The proportionate mortality from lung cancer was significantly elevated (PMR = 2.05; 95% CI 1.65 to 2.52). A statistically significant increase in proportionate mortality due to respiratory (PMR = 1.7; 95% CI 1.2 to 2.34). and lung cancer (PMR = 1.67;95% CI = 1.15-2.34) among maintenance workers has been observed. The PMR among the three groups of workers (production, maintenance, office) did differ significantly for lung cancer (p = 0.001), while the PMR for urinary bladder cancer found to be similar among the three groups of cement workers. Conclusion Cement production, and maintenance workers presented increased lung and respiratory cancer proportionate mortality, and this finding probably cannot be explained by the confounding effect of smoking alone. Further research including use of prospective cohort studies is needed in order to establish a causal association between occupational exposure to cement and risk of lung cancer. PMID:22738120

Solidification of low-level radioactive liquid waste using a cement-silicate process

International Nuclear Information System (INIS)

Grandlund, R.W.; Hayes, J.F.

1979-01-01

Extensive use has been made of silicate and Portland cement for the solidification of industrial waste and recently this method has been successfully used to solidify a variety of low level radioactive wastes. The types of wastes processed to date include fuel fabrication sludges, power reactor waste, decontamination solution, and university laboratory waste. The cement-silicate process produces a stable solid with a minimal increase in volume and the chemicals are relatively inexpensive and readily available. The method is adaptable to either batch or continuous processing and the equipment is simple. The solid has leaching characteristics similar to or better than plain Portland cement mixtures and the leaching can be further reduced by the use of ion-exchange additives. The cement-silicate process has been used to solidify waste containing high levels of boric acid, oils, and organic solvents. The experience of handling the various types of liquid waste with a cement-silicate system is described

Competitiveness and carbon leakages in industry under asymmetric climate policy

International Nuclear Information System (INIS)

Demailly, D.

2008-02-01

This research aims at studying how to predict competitiveness loss for an industry submitted to an asymmetric carbon constraint, and carbon leakages, whether high losses and important leakages might be feared, and which policies can be used to mitigate these losses and escapes. The author analyses and comments the content of four articles dealing with: the impact on competitiveness, revenue distribution and economic efficiency of a change in the allocation rules for EU greenhouse gas allowances; the relationship between allocation of CO 2 allowances and competitiveness in the case of the European iron and steel industry; CO 2 abatement, competitiveness and leakage in the European cement industry under EU ETS; and leakage from climate policies and border tax adjustment (lessons from a geographic model of the cement industry). Then, the author combines several approaches to study the cement and steel industries

Evaluation of the amount of excess cement around the margins of cement-retained dental implant restorations: the effect of the cement application method.

Science.gov (United States)

Chee, Winston W L; Duncan, Jesse; Afshar, Manijeh; Moshaverinia, Alireza

2013-04-01

Complete removal of excess cement from subgingival margins after cementation of implant-supported restorations has been shown to be unpredictable. Remaining cement has been shown to be associated with periimplant inflammation and bleeding. The purpose of this study was to investigate and compare the amount of excess cement after cementation with 4 different methods of cement application for cement-retained implant-supported restorations. Ten implant replicas/abutments (3i) were embedded in acrylic resin blocks. Forty complete veneer crowns (CVCs) were fabricated by waxing onto the corresponding plastic waxing sleeves. The wax patterns were cast and the crowns were cemented to the implant replicas with either an interim (Temp Bond) or a definitive luting agent (FujiCEM). Four methods of cement application were used for cementation: Group IM-Cement applied on the internal marginal area of the crown only; Group AH-Cement applied on the apical half of the axial walls of the crown; Group AA-Cement applied to all axial walls of the interior surface of the crown, excluding the occlusal surface; and Group PI-Crown filled with cement then seated on a putty index formed to the internal configuration of the restoration (cementation device) (n=10). Cement on the external surfaces was removed before seating the restoration. Cement layers were applied on each crown, after which the crown was seated under constant load (80 N) for 10 minutes. The excess cement from each specimen was collected and measured. One operator performed all the procedures. Results for the groups were compared, with 1 and 2-way ANOVA and the Tukey multiple range test (α=.05). No significant difference in the amount of excess/used cement was observed between the 2 different types of cements (P=.1). Group PI showed the least amount of excess cement in comparison to other test groups (P=.031). No significant difference was found in the amount of excess cement among groups MI, AH, and AA. Group AA showed the

Recycling of porcelain tile polishing residue in portland cement: hydration efficiency.

Science.gov (United States)

Pelisser, Fernando; Steiner, Luiz Renato; Bernardin, Adriano Michael

2012-02-21

Ceramic tiles are widely used by the construction industry, and the manufacturing process of ceramic tiles generates as a major residue mud derived from the polishing step. This residue is too impure to be reused in the ceramic process and is usually discarded as waste in landfills. But the analysis of the particle size and concentration of silica of this residue shows a potential use in the manufacture of building materials based on portland cement. Tests were conducted on cement pastes and mortars using the addition of 10% and 20% (mass) of the residue. The results of compressive strength in mortars made up to 56 days showed a significant increase in compressive strength greater than 50%. The result of thermogravimetry shows that portlandite is consumed by the cement formed by the silica present in the residue in order to form calcium silicate hydrate and featuring a pozzolanic reaction. This effect improves the performance of cement, contributes to research and application of supplementary cementitious materials, and optimizes the use of portland cement, reducing the environmental impacts of carbon dioxide emissions from its production.

76 FR 76760 - Gray Portland Cement and Cement Clinker From Japan

Science.gov (United States)

2011-12-08

... and Cement Clinker From Japan Determination On the basis of the record \\1\\ developed in the subject... duty order on gray Portland cement and cement clinker from Japan would be likely to lead to... and Cement Clinker from Japan: Investigation No. 731- TA-461 (Third Review). By order of the...

Renewable and dangerous residues as industrial fuels. Study about hard environmental support in the cement production in Brazil, years 1990; Residuos renovaveis e perigosos como combustiveis industriais. Estudo sobre a dificil sustentacao ambiental da fabricacao de cimento no Brasil, anos 1990

Energy Technology Data Exchange (ETDEWEB)

Santi, Auxiliadora Maria Moura [Fundacao Estadual do Meio Ambiente, Belo Horizonte, MG (Brazil); Seva Filho, Arsenio Oswaldo [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia

1999-07-01

The aim of the work is to indicate new fuels to Brazilian cement industry. A comparative study is presented. The renewable energetic sources, not renewable energetic sources, and residues of other industrial processes are analyzed.

The comparison analysis of total factor productivity and eco-efficiency in China's cement manufactures

International Nuclear Information System (INIS)

Long, Xingle; Zhao, Xicang; Cheng, Faxin

2015-01-01

This paper mainly compares total factor productivity and eco-efficiency in China's cement manufactures from 2005 to 2010. First, we evaluate total factor productivity and eco-efficiency of China's cement manufactures through distance function and directional slack-based measure (DSBM) respectively. Furthermore, we also explore the difference of total factor productivity and eco-efficiency. Last, we investigate the determinants of Malmquist, Mamlquist–Luenberger of China's cement manufactures through random-effect Tobit and bootstrap truncated econometric methods. We find that there are some gaps between Malmquist and Mamlquist–Luenberger of China's cement manufactures. Per labor cement industry value has U-shape relationship with both Malmquist and Malmquist–Luenberger. It is necessary to adopt advanced technology to reduce pollutant emissions. -- Highlights: •Eco-efficiency of cement manufactures is evaluated through slack-based measure. •Eco-efficiency of China's cement manufactures has biases with total factor productivity. •Environmental Kuznets curve is existed for China's cement manufactures

The transformation of waste Bakelite to replace natural fine aggregate in cement mortar

Directory of Open Access Journals (Sweden)

Nopagon Usahanunth

2017-06-01

Full Text Available Bakelite material has been used to produce the various components for cars and consumer goods industry in Thailand. The growth of Bakelite consumption increases Bakelite waste. Bakelite waste is prohibited from disposing of direct landfilling and open burning because of the improper disposal and emission reasons. A large amount of this waste needs the large safe space of warehouse area for keeping which becomes a waste management problem. Size reduction by milling machine is helpful for waste handling and storing, however, the post-milling waste Bakelite plastic utilization shall be studied to maintain the waste storing capacity. There are some studies of the milling machine used for waste plastic size reduction. However, the particular study of milling machine application for waste size reduction and its milling waste utilization is still insufficient in Thailand. The purpose of this research is the use of waste Bakelite aggregate milling machine for Bakelite waste size reduction and use of the post-milling waste Bakelite as a fine aggregate to replace natural sand material in cement mortar. The waste Bakelite fine aggregate (WBFA was mixed in cement mortar mixture with the proportion 0% 20% 40% 60% 80% and 100% by volume for cement mortar sample preparation. The mortar sample was tested for compressive strength follow ASTM standard. The compressive test result of mortar samples will be compared between conventional mortar (0% WBFA and waste Bakelite mortar (WBM as well as comparing with the mortar standard. From an analysis of the sample test data found that the WBFA content in cement mortar mixture can predict the strength of WBM. The compressive strength of WBM at 28 days age with the fraction of WBFA is not exceeded 11.03%, and 23.08% respectively can be met the mortar standard according to the equation. The utilization of WBM to develop mortar non-structural mortar product can be usable from a technical point of view.

Cementing a wellbore using cementing material encapsulated in a shell

Energy Technology Data Exchange (ETDEWEB)

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Spadaccini, Christopher M.; Cowan, Kenneth Michael

2016-08-16

A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

Cementing a wellbore using cementing material encapsulated in a shell

Energy Technology Data Exchange (ETDEWEB)

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Floyd, III, William C.; Spadaccini, Christopher M.; Vericella, John J.; Cowan, Kenneth Michael

2017-03-14

A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

Fine natural aggregate replacement for sandy residue from itabirite exploitation in Portland cement mortar

International Nuclear Information System (INIS)

Melo, V.A.R.; Freire, C.B.; Pereira Junior, S.S.; Lameiras, F.S.; Tello, C.C.O.

2011-01-01

The fine natural aggregates are a material largely used by the civil construction for mortar and concrete production. Due to tightening legal restrictions imposed on their extraction, alternative materials are being considered. The use of sandy residue from BIF (banded iron formations) exploitation was investigated. It requires their grinding and flotation to concentrate iron oxides. Large amounts of sandy residue composed of quartz and iron oxides are generated in this process. The sandy residue was characterized relative to mineralogical composition, particle size distribution, presence of organic impurities, and particle shape. Mortar formulations were prepared by varying the type of cement, the cement to aggregate proportion and the water/cement ratio (a/c). The results of viscosity and density of fresh mortar, setting time, and compressive strength are presented. Compressive strength up to 19.5 MPa at 28 days were achieved with the use of cement CPV, a/c ratio of 0.80 and cement:aggregate proportion of 1:2. The results demonstrate the technical feasibility of using sandy residue as fine aggregate. (author)

Lung function reduction and chronic respiratory symptoms among workers in the cement industry: a follow up study

Directory of Open Access Journals (Sweden)

Zeleke Zeyede K

2011-11-01

Full Text Available Abstract Background There are only a few follow-up studies of respiratory function among cement workers. The main aims of this study were to measure total dust exposure, to examine chronic respiratory symptoms and changes in lung function among cement factory workers and controls that were followed for one year. Methods The study was conducted in two cement factories in Ethiopia. Totally, 262 personal measurements of total dust among 105 randomly selected workers were performed. Samples of total dust were collected on 37-mm cellulose acetate filters placed in closed faced Millipore-cassettes. Totally 127 workers; 56 cleaners, 44 cement production workers and 27 controls were randomly selected from two factories and examined for lung function and interviewed for chronic respiratory symptoms in 2009. Of these, 91 workers; 38 cement cleaners (mean age 32 years, 33 cement production workers (36 years and 20 controls (38 years were examined with the same measurements in 2010. Results Total geometric mean dust exposure among cleaners was 432 mg/m3. The fraction of samples exceeding the Threshold Limit Value (TLV of 10 mg/m3 for the cleaners varied from 84-97% in the four departments. The levels were considerably lower among the production workers (GM = 8.2 mg/m3, but still 48% exceeded 10 mg/m3. The prevalence of all the chronic respiratory symptoms among both cleaners and production workers was significantly higher than among the controls. Forced Expiratory Volume in one second (FEV1 and FEV1/Forced Vital Capacity (FEV1/FVC were significantly reduced from 2009 to 2010 among the cleaners (p Conclusions The high prevalence of chronic respiratory symptoms and reduction in lung function is probably associated with high cement dust exposure. Preventive measures are needed to reduce the dust exposure.

Case study: evaluation of continuos blending silos in the cement industry, by the aid of tracer techniques

International Nuclear Information System (INIS)

Sebastian, C.; Maghella, G.; Mamani, E.

2000-12-01

Besides the actual burning process in cement manufacture, particular importance is attached to raw material preparation and homogenization, not only because of the quality of the kiln fed and therefore of the produced cement, but also because of the economy of the kiln operation, which significantly depends on the uniformity of the chemical composition of the material. As a result, the blending process of the cement raw material, before burning, is a basic stage of cement technology production. In this case, the pneumatic homogenization process is studied in a silo with a great storing and processing capacity. The objective is to evaluate the parameters which influence in the continuos operation. The method allows us to determine the optimal blending parameters, through the observation of the movement and distribution of the different fractions of fine dust raw meal, labelled with La-140 as tracer. Changes in blending according to time are discussed as well as the influence of the silo design on the degree of homogenization. It was showed that the silo blending operation has a strong influence on the production of good-quality cement as well as the implications on energy saving

Natural cement as the precursor of Portland cement: Methodology for its identification

International Nuclear Information System (INIS)

Varas, M.J.; Alvarez de Buergo, M.; Fort, R.

2005-01-01

When cements appeared in the 19th century, they took the place of traditional binding materials (lime, gypsum, and hydraulic lime) which had been used until that time. Early cements can be divided into two groups, natural and artificial (Portland) cements. Natural cements were introduced first, but their widespread usage was short-lived as they were quickly replaced by artificial cements (Portland), still the most important and predominant today. The main differences between natural and artificial cements arise during the manufacturing process. The final properties of the cements are greatly influenced by differences in the raw materials and burning temperatures employed. The aim of this paper is to assess the efficiency of traditional analytical techniques (petrographic microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR)) used to differentiate natural and artificial cements

Environmental and energy assessment of the use of Andesite in cement

Directory of Open Access Journals (Sweden)

Hamidi Moussa

2018-01-01

Full Text Available The present study is a contribution to the research of new sources of supply of additions and raw materials in order to valorize local materials in the manufacture of cement. It consists in checking the environmental validity of the industrial use of andesite by evaluating the energy consumption of manufacturing andesitic cement. This evaluation was made on CEMI 52.5R type cement mortars whose basic constituent is clinker, with substitution rates of raw and calcined andesitic rock at 800 °C varying from 0-40%. and this through mechanical performance tests at several deadlines (2 days, 7 days, 28 days and 90 days. The results show that the analysis of the influence on the environment of this addition, in its raw state or calcined at 800 ° C, made it possible to say that globally the impact of andesite on the matrices seems positive to long term. The replacement of the cement by andesite systematically induces a reduction in the energy required to produce one ton of binder, due to the lower energy demand for grinding than that required for the thermal treatment of the clinker. Overall, the energy cost of andesite cement (in kWh per MPa compressive strength is lower than that of ordinary cement for low rates of clinker replacement and obtaining cements with moderate strengths.

Influence of ferrite phase in alite-calcium sulfoaluminate cements

Science.gov (United States)

Duvallet, Tristana Yvonne Francoise

Since the energy crisis in 1970's, research on low energy cements with low CO2- emissions has been increasing. Numerous solutions have been investigated, and the goal of this original research is to create a viable hybrid cement with the components of both Ordinary Portland cement (OPC) and calcium sulfoaluminate cement (CSAC), by forming a material that contains both alite and calcium sulfoaluminate clinker phases. Furthermore, this research focuses on keeping the cost of this material reasonable by reducing aluminum requirements through its substitution with iron. The aim of this work would produce a cement that can use large amounts of red mud, which is a plentiful waste material, in place of bauxite known as an expensive raw material. Modified Bogue equations were established and tested to formulate this novel cement with different amounts of ferrite, from 5% to 45% by weight. This was followed by the production of cement from reagent chemicals, and from industrial by-products as feedstocks (fly ash, red mud and slag). Hydration processes, as well as the mechanical properties, of these clinker compositions were studied, along with the addition of gypsum and the impact of a ferric iron complexing additive triisopropanolamine (TIPA). To summarize this research, the influence of the addition of 5-45% by weight of ferrite phase, was examined with the goal of introducing as much red mud as possible in the process without negatively attenuate the cement properties. Based on this PhD dissertation, the production of high-iron alite-calcium sulfoaluminateferrite cements was proven possible from the two sources of raw materials. The hydration processes and the mechanical properties seemed negatively affected by the addition of ferrite, as this phase was not hydrated entirely, even after 6 months of curing. The usage of TIPA counteracted this decline in strength by improving the ferrite hydration and increasing the optimum amount of gypsum required in each composition

Accurate quantitative XRD phase analysis of cement clinkers

International Nuclear Information System (INIS)

Kern, A.

2002-01-01

Full text: Knowledge about the absolute phase abundance in cement clinkers is a requirement for both, research and quality control. Traditionally, quantitative analysis of cement clinkers has been carried out by theoretical normative calculation from chemical analysis using the so-called Bogue method or by optical microscopy. Therefore chemical analysis, mostly performed by X-ray fluorescence (XRF), forms the basis of cement plan control by providing information for proportioning raw materials, adjusting kiln and burning conditions, as well as cement mill feed proportioning. In addition, XRF is of highest importance with respect to the environmentally relevant control of waste recovery raw materials and alternative fuels, as well as filters, plants and sewage. However, the performance of clinkers and cements is governed by the mineralogy and not the elemental composition, and the deficiencies and inherent errors of Bogue as well as microscopic point counting are well known. With XRD and Rietveld analysis a full quantitative analysis of cement clinkers can be performed providing detailed mineralogical information about the product. Until recently several disadvantages prevented the frequent application of the Rietveld method in the cement industry. As the measurement of a full pattern is required, extended measurement times made an integration of this method into existing automation environments difficult. In addition, several drawbacks of existing Rietveld software such as complexity, low performance and severe numerical instability were prohibitive for automated use. The latest developments of on-line instrumentation, as well as dedicated Rietveld software for quantitative phase analysis (TOPAS), now make a decisive breakthrough possible. TOPAS not only allows the analysis of extremely complex phase mixtures in the shortest time possible, but also a fully automated online phase analysis for production control and quality management, free of any human interaction

Utilization of Iron Ore Tailings as Raw Material for Portland Cement Clinker Production

Directory of Open Access Journals (Sweden)

Li Luo

2016-01-01

Full Text Available The cement industry has for some time been seeking alternative raw material for the Portland cement clinker production. The aim of this research was to investigate the possibility of utilizing iron ore tailings (IOT to replace clay as alumina-silicate raw material for the production of Portland cement clinker. For this purpose, two kinds of clinkers were prepared: one was prepared by IOT; the other was prepared by clay as a reference. The reactivity and burnability of raw meal, mineralogical composition and physical properties of clinker, and hydration characteristic of cement were studied by burnability analysis, differential thermal analysis, X-ray diffraction, and hydration analysis. The results showed that the raw meal containing IOT had higher reactivity and burnability than the raw meal containing clay, and the use of IOT did not affect the formation of characteristic mineralogical phases of Portland cement clinker. Furthermore, the physical and mechanical performance of two cement clinkers were similar. In addition, the use of IOT was found to improve the grindability of clinker and lower the hydration heat of Portland cement. These findings suggest that IOT can replace the clay as alumina-silicate raw material for the preparation of Portland cement clinker.

Dust and smoke pollution monitoring in industrial unit

International Nuclear Information System (INIS)

Shamsi, S.S.

1995-01-01

Dust and smoke are the two most commonly emitted industrial pollutants which are visible to the naked eye. Cement plants and power generation plants, based on coal and fuel oil etc. are the most common examples of industry emitting these pollutants. In this article these pollutants have been briefly described and some monitoring instruments for dust and smoke emissions have been specific. These instruments are especially suitable for power station and the cement industry etc. Automotive in urban areas. However, this paper does not include equipment for automotive exhaust pollution. (author)

Feasibility of producing nano cement in a traditional cement factory in Iraq

Directory of Open Access Journals (Sweden)

Sada Abdalkhaliq Hasan Alyasri

2017-12-01

Full Text Available This study investigates the economic feasibility of producing nano cement through the establishment of a production line within an existing cement factory. Creating a nano cement production line within the Alkufa Cement factory in Iraq is selected as a case study. Evaluation measures including internal rate of return (IRR, net present value (NPV and breakeven point (BEP are used to evaluate the possible gain that can be achieved from this option. The results demonstrated a positive NPV. The IRR is found to be 26.8% and BEP is reached within 3 years after the establishment of the line. This indicates that producing nano cement in the existing cement factory is economically feasible and can be more advantageous than the ordinary cement.

Effectiveness of the Top-Down Nanotechnology in the Production of Ultrafine Cement (~220 nm

Directory of Open Access Journals (Sweden)

Byung-Wan Jo

2014-01-01

Full Text Available The present investigation is dealing with the communition of the cement particle to the ultrafine level (~220 nm utilizing the bead milling process, which is considered as a top-down nanotechnology. During the grinding of the cement particle, the effect of various parameters such as grinding time (1–6 h and grinding agent (methanol and ethanol on the production of the ultrafine cement has also been investigated. Performance of newly produced ultrafine cement is elucidated by the chemical composition, particle size distribution, and SEM and XRD analyses. Based on the particle size distribution of the newly produced ultrafine cement, it was assessed that the size of the cement particle decreases efficiently with increase in grinding time. Additionally, it is optimized that the bead milling process is able to produce 90% of the cement particle <350 nm and 50% of the cement particle < 220 nm, respectively, after 6.3 h milling without affecting the chemical phases. Production of the ultrafine cement utilizing this method will promote the construction industries towards the development of smart and sustainable construction materials.

The mechanical effect of the existing cement mantle on the in-cement femoral revision.

Science.gov (United States)

Keeling, Parnell; Lennon, Alexander B; Kenny, Patrick J; O'Reilly, Peter; Prendergast, Patrick J

2012-08-01

Cement-in-cement revision hip arthroplasty is an increasingly popular technique to replace a loose femoral stem which retains much of the original cement mantle. However, some concern exists regarding the retention of the existing fatigued and aged cement in such cement-in-cement revisions. This study investigates whether leaving an existing fatigued and aged cement mantle degrades the mechanical performance of a cement-in-cement revision construct. Primary cement mantles were formed by cementing a polished stem into sections of tubular steel. If in the test group, the mantle underwent conditioning in saline to simulate ageing and was subject to a fatigue of 1 million cycles. If in the control group no such conditioning or fatigue was carried out. The cement-in-cement procedure was then undertaken. Both groups underwent a fatigue of 1 million cycles subsequent to the revision procedure. Application of a Mann-Whitney test on the recorded subsidence (means: 0.51, 0.46, n=10+10, P=0.496) and inducible displacement (means: 0.38, 0.36, P=0.96) revealed that there was no statistical difference between the groups. This study represents further biomechanical investigation of the mechanical behaviour of cement-in-cement revision constructs. Results suggest that pre-revision fatigue and ageing of the cement may not be deleterious to the mechanical performance of the revision construct. Thus, this study provides biomechanical evidence to back-up recent successes with this useful revision technique. Copyright © 2012 Elsevier Ltd. All rights reserved.

The thermoelectric generators use for waste heat utilization from cement plant

Directory of Open Access Journals (Sweden)

Sztekler Karol

2017-01-01

Production often entails the formation of by-product which is waste heat. One of the equipment processing heat into electricity is a thermoelectric generator. Its operation is based on the principle of thermoelectric phenomenon, which is known as a Seebeck phenomenon. The simplicity of thermoelectric phenomena allows its use in various industries, in which the main waste product is in the form of heat with the temperature of several hundred degrees. The study analyses the possibility of the thermoelectric systems use for the waste heat utilization resulting in the cement production at the cement plant. The location and design of the thermoelectric system that could be implemented in cement plant is chosen. The analysis has been prepared in the IPSEpro software.

The improved heat integration of cement production under limited process conditions: A case study for Croatia

International Nuclear Information System (INIS)

Boldyryev, Stanislav; Mikulčić, Hrvoje; Mohorović, Zoran; Vujanović, Milan; Krajačić, Goran; Duić, Neven

2016-01-01

Given that cement is the most widely used material for housing and modern infrastructure needs, this paper analyses the energy efficiency of the cement manufacturing processes for a particular cement plant. The cement industry is one of the largest consumers of carbon-containing primary energy sources and one of the primary polluters of the environment, emitting approximately 5% of global pollution. Energy consumption represents the largest part of the production cost for cement factories and has a significant influence on product prices. Given that it is realised in modern society that infrastructural projects lead to a higher level of economy and sustainability for countries, reducing the production cost in the cement industry is a very important problem. The authors analysed the energy consumption of a particular cement factory in Croatia to determine the minimum energy targets of production and proposed pathways to improve energy efficiency. The Process Integration approach was used in this study. Nevertheless, the features of the cement factory forced the research to update its methodological steps to propose real pathways for a retrofit project with the aim of achieving the optimal minimum temperature difference between process streams. There are various streams, including those that contain solid particles, gas and air streams, and streams, that should be cooled down rapidly; these facts become more complicated by the special construction of the process equipment, which causes heat transfer between some streams to be impossible. The main objective of this paper is to determine the potential of real energy savings and propose a solution for a new concept of heat exchanger network (HEN) that avoids the process traps and provides a feasible retrofit. The maximum heat recovery of that production of a particular type of cement was determined and improved when a HEN was built. The authors conclude that the energy consumption of the cement factory can be reduced by

New Medium for Isolation of Bacteria From Cement Kiln Dust with a Potential to Apply in Bio-Concrete

Science.gov (United States)

Alshalif, A. F.; Irwan, J. M.; Othman, N.; Al-Gheethi, A.

2018-04-01

The present study aimed to introduce a new isolation medium named kiln dust medium (KDM) for recovering of bacteria from cement kiln dust with high pH (>pH 11) without the need for nutrients additives. The cement kiln dust samples were collected from five different areas of Cement Industries of Malaysia Berhad (CIMA). The bacterial isolates were recovered on KDM by direct plating technique. The chemical components for all collected samples were identified using X-ray fluorescence (XRF). The primary identification for the bacterial isolates indicated that these bacteria belongs to Bacillus spp. Based on the morphological characteristics. The growth curve of the bacterial strains was monitored using the optical density (OD) with 650 nm wavelength, which in role confirmed that all isolated bacteria had the ability to grow successfully in the proposed medium. The ability of the bacterial strains to grow at high pH reflects their potential in the bio-concrete applications (aerated and non-aerated concrete). These findings indicated that the cement kiln dust samples from Cement Industries represent the most appropriate source for bacteria used in the bioconcrete.

Oxygen transport membranes for biomass gasification and cement industry

OpenAIRE

Cheng, Shiyang; Hendriksen, Peter Vang; Kaiser, Andreas; Søgaard, Martin

2015-01-01

I dette projekt er udviklet keramiske ilt-membraner til anvendelse ved fremstilling af ren ilt. Membranerne egner sig endvidere til at levere ilt til en række høj-temperatur processer så som ilt-blæst termisk forgasning af biomasse, cement fremstilling og diverse ”oxyfuel” processer til omsætning af kul med CO2-indfagning. De udviklede membraner er alle baseret på Gd0.1Ce0.9O1.95-δ (GCO). Betydningen af diverse substituenter (f.eks. Pr og Co), der kan øge materialets elektronledningsevne, og ...

Waste-form development for conversion to portland cement at Los Alamos National Laboratory (LANL) Technical Area 55 (TA-55)

International Nuclear Information System (INIS)

Veazey, G.W.; Schake, A.R.; Shalek, P.D.; Romero, D.A.; Smith, C.A.

1996-10-01

The process used at TA-55 to cement transuranic (TRU) waste has experienced several problems with the gypsum-based cement currently being used. Specifically, the waste form could not reliably pass the Waste Isolation Pilot Plant (WIPP) prohibition for free liquid and the Environmental Protection Agency (EPA)-Toxicity Characteristic Leaching Procedure (TCLP) standard for chromium. This report describes the project to develop a portland cement-based waste form that ensures compliance to these standards, as well as other performance standards consisting of homogeneous mixing, moderate hydration temperature, timely initial set, and structural durability. Testing was conducted using the two most common waste streams requiring cementation as of February 1994, lean residue (LR)- and oxalate filtrate (OX)-based evaporator bottoms (EV). A formulation with a pH of 10.3 to 12.1 and a minimum cement-to-liquid (C/L) ratio of 0.80 kg/l for OX-based EV and 0.94 kg/L for LR-based EV was found to pass the performance standards chosen for this project. The implementation of the portland process should result in a yearly cost savings for raw materials of approximately $27,000 over the gypsum process

Admixtures in Cement-Matrix Composites for Mechanical Reinforcement, Sustainability, and Smart Features

Science.gov (United States)

Bastos, Guillermo; Patiño-Barbeito, Faustino; Patiño-Cambeiro, Faustino; Armesto, Julia

2016-01-01

For more than a century, several inclusions have been mixed with Portland cement—nowadays the most-consumed construction material worldwide—to improve both the strength and durability required for construction. The present paper describes the different families of inclusions that can be combined with cement matrix and reviews the achievements reported to date regarding mechanical performance, as well as two other innovative functionalities of growing importance: reducing the high carbon footprint of Portland cement, and obtaining new smart features. Nanomaterials stand out in the production of such advanced features, allowing the construction of smart or multi-functional structures by means of thermal- and strain-sensing, and photocatalytic properties. The first self-cleaning concretes (photocatalytic) have reached the markets. In this sense, it is expected that smart concretes will be commercialized to address specialized needs in construction and architecture. Conversely, other inclusions that enhance strength or reduce the environmental impact remain in the research stage, in spite of the promising results reported in these issues. Despite the fact that such functionalities are especially profitable in the case of massive cement consumption, the shift from the deeply established Portland cement to green cements still has to overcome economic, institutional, and technical barriers. PMID:28774091

Recomendations concerning technical research and development with the purpose to industrially exploit marine algae

Energy Technology Data Exchange (ETDEWEB)

Hahn-Haegerdal, B.

1980-10-01

This report formulates a proposal for a program for technical research and development concerning use of Marine algae.The report is based on a retrospective literature search, an inquiry to potential algae users and producers in Sweden, visits to and correspondence with scientists and industries in Sweden and abroad. Technical research and development concerning marine algae is needed within the following fields: -Development of new sorts of algae offering resistance to parasite and disease adoptation to cultivation and har- vesting systems,and high-yielding concerning technically interesting components. -Development of suitable cultivation systems for Swedish conditions. -Co-cultivation of fish, mussels, oysters and crustaceans with algae. -Development of harvesting systems. -Methane rotting. -Fatty acid/hydrocarbon production as an alternative to methane rotting. -Physical-chemical properties of marine polysaccharides in relation to their technical properties. -Marine algae as fodder supplement.

Cement for Oil Well Cementing Operations in Ghana

African Journals Online (AJOL)

Michael

For Portland cement to qualify as oil well cement, the chemical and physical properties must meet ..... Reservoir Engineering, Stanford University,. Stanford, California, pp. ... Construction”, PhD Thesis, Kwame Nkrumah. University of Science ...

Effect of blastfurnace slag addition to Portland cement for cationic exchange resins encapsulation

Directory of Open Access Journals (Sweden)

Stefan L.

2013-07-01

Full Text Available In the nuclear industry, cement-based materials are extensively used to encapsulate spent ion exchange resins (IERs before their final disposal in a repository. It is well known that the cement has to be carefully selected to prevent any deleterious expansion of the solidified waste form, but the reasons for this possible expansion are not clearly established. This work aims at filling the gap. The swelling pressure of IERs is first investigated as a function of ions exchange and ionic strength. It is shown that pressures of a few tenths of MPa can be produced by decreases in the ionic strength of the bulk solution, or by ion exchanges (2Na+ instead of Ca2+, Na+ instead of K+. Then, the chemical evolution of cationic resins initially in the Na+ form is characterized in CEM I (Portland cement and CEM III (Portland cement + blastfurnace slag cements at early age and an explanation is proposed for the better stability of CEM III material.