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CO2 emission reduction in the cement industry by using a solar calciner

CO2 emission reduction in the cement industry by using a solar calciner

DNI data in hourly resolution for Almeria was obtained from Meyer and Schwandt [ 31 , 32 ]. Two data sets are used for the anal- ysis, namely the P95 data for the base case and the P50 data set for investigation of a year with higher solar irradiation compared to the base case. P95 describes a data set, compared to which 95% of all years will have better annual solar irradiation and only 5% of years will have lower irradiation. Hence, this data is suitable for a con- servative estimation of the potentials of solar cement plants. The P50 data, on the other hand, represents a “typical metrological year ”, where the chance that one year's annual irradiation is higher or lower than the given data is 50%. Using this data for assessing the potential of a solar cement plant, which is in operation for many years, is hence more optimistic. With the given data set by Meyer and Schwandt, P50 and P95 represent the most optimistic and conservative approach, respectively. Both cases are compared in the following table ( Table 2 ).
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Heavy metals in cement and concrete resulting from the co-incineration of wastes in cement kilns with regard to the legitimacy of waste utilisation

Heavy metals in cement and concrete resulting from the co-incineration of wastes in cement kilns with regard to the legitimacy of waste utilisation

If a certain type of waste is to be used in a cement plant, the question arises to the licensing authority, whether the use of this type of waste can be permitted. For this purpose, the “Arbeitshilfe Stoffflussanalyse bei abfallrechtlichen Beurteilungsfragen” (Material flow analysis as an Aid in Assessment under Waste Management Legislation) was developed. Among others, it is used in Northrhine-Westfalia. This aid also contains emission factors for cement plants. These values are based on values measured by the VDZ in the individual plants and were included in the aid after intensive discussions among various groups of interested parties (see figures 48 through 50, bar EF-SFA). These emission factors are used to check in advance whether certain emission limits associated with the use of waste are observed. Irrespective of this preliminary estimation, continuous measurements are to be carried out during actual use of these wastes in order to ensure that the given emission limits are observed. As no better method exists at the moment, this procedure seems to be reasonable. As described by the aid, however, plant-specific data should be used to the largest possible extent.
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Rent sharing to control non-cartel supply in the German cement market

Rent sharing to control non-cartel supply in the German cement market

information on product types, dates of purchases, delivered quantities, involved intermediaries, cancellations, rebates, early payment discounts, and free-off charge deliveries as well as locations of the cement plants and unloading points. We have supplemented this raw data set with information on all cement plants located in Germany as well as those near the German border. Using Google Maps, all coordinates were retrieved for each unloading point in our sample and the number of independent cement suppliers located within a radius of 150 kilometers (road distance) of those coordinates serves as a measure of the set of available suppliers to a customer. Additionally, we calculated the road distance to the nearest East European plant and added data about regional construction activity from the German Statistical Office to capture demand fluctuations.
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Integrated assessment of CO2 reduction technologies in China's cement industry

Integrated assessment of CO2 reduction technologies in China's cement industry

It can be found that a total of 2.5, 4.7 and 4.3 Gt tonnes of CO 2 will be saved in the respective scenarios up to 2050 shown in Figure 4. It also shows the annual CO 2 reduction generated by these measures with CCS. The emission reduction curves initially rise and then decline in all scenarios. Reductions peak at around 2025; the other inflection point is 2035, which strongly signifies the impact of cement output. There are two significant reversal points in 2030 and 2035. The first inflection point is due to the introduction of CCS, whereas the second is caused mainly by a more widespread use of CCS. The reduction in emissions between 2030 and 2035 is affected by a reduction in output. Background information is that most advanced cement plants were built during 2005-2010 in China, and their lifetime is 25 years. Moreover, based on the assumption in Table 2, there is a sudden increase around 2030.
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Carbon Capture for CO2 Emission Reduction in the Cement Industry in Germany

Carbon Capture for CO2 Emission Reduction in the Cement Industry in Germany

For CO 2 capture, steam supply plays a key role; four cases are assessed in the scenario analysis. In the base case and case 2, steam for supplying the reboiler heat demand is imported, and the associated emissions not captured. In case 3, steam is produced in an onsite coal boiler, and in case 4, steam and electricity are produced in a coal CHP. The boiler and CHP-associated emissions are captured in the post-combustion capture plant, too. The results show that the specific thermal energy requirement (3.5–3.8 MJ th /kg CO2 ), specific cooling demand (4.3–4.5 MJ th /kg CO2 ), specific compressor work (0.3 MJ el /kg CO2 ), and specific total work consumption (0.4 MJ el /kg CO2 ) only vary slightly across all cases. The same holds for the carbon capture costs, which amount to 63.6 EUR/t in the base case and 60.5, 60.9, and 54.4 EUR/t in cases 2, 3, and 4, respectively. For the CO 2 avoidance costs, however, the investigated cases show a significant difference. While in the base case and case 2, CO 2 avoidance costs are determined at 81.7 and 77.7 EUR/t, in case 3 and case 4, avoidance costs rise sharply to 115 and 107 EUR/t. This is also reflected in the clinker costs. For the base case, case 2, case 3, and case 4, clinker costs are 108, 105, 131, and 136 EUR/t, respectively. The cost difference stems from the much higher flue gas streams and lower CO 2 contents in the flue gas for cases 3 and 4. The CO 2 avoidance rate is most favorable in case 4, with 90%, while in the base case, case 2, and 3, the avoidance rates were at 70%, 71%, and 74%, respectively. The importance of the steam and electricity supply was underlined in the sensitivity analysis, which showed that these factors, together with the purchased equipment costs and interest rate, have the highest influence on the CO 2 avoidance costs. The obtained results fit well with the existing literature on CO 2 capture for cement plants.
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CO2 emission reduction in the cement industry by using a solar calciner

CO2 emission reduction in the cement industry by using a solar calciner

DNI data in hourly resolution for Almeria was obtained from Meyer and Schwandt [ 31 , 32 ]. Two data sets are used for the anal- ysis, namely the P95 data for the base case and the P50 data set for investigation of a year with higher solar irradiation compared to the base case. P95 describes a data set, compared to which 95% of all years will have better annual solar irradiation and only 5% of years will have lower irradiation. Hence, this data is suitable for a con- servative estimation of the potentials of solar cement plants. The P50 data, on the other hand, represents a “typical metrological year ”, where the chance that one year's annual irradiation is higher or lower than the given data is 50%. Using this data for assessing the potential of a solar cement plant, which is in operation for many years, is hence more optimistic. With the given data set by Meyer and Schwandt, P50 and P95 represent the most optimistic and conservative approach, respectively. Both cases are compared in the following table ( Table 2 ).
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Thermochemical characterisation of the gas circulation in the relevant cement industry processes

Thermochemical characterisation of the gas circulation in the relevant cement industry processes

has significant influence for transport of atom Na, figure 5.16. That was also confirmed in the presented results of the industrial samples vaporisation studies. It is also worth to discuss the influence of the alternative fuels on the vaporisation rate. In the case of materials coming from cement plants II and I, where enormous amounts of alternative fuels are used, the vaporisation of the volatilities is the highest from all the materials under investigation. The intensities of sulphur and alkalis were the highest in the case of those two cement plants. Also high vaporisation of sulphur and alkalis was detected in the case of materials coming from cement plant III. The lowest quantity of alkali sulphate/chloride vaporisation was detected in the case of cement plant IV, where mostly brown coal and brow coal dust and the low fluff content as alternative fuel are used. The chlorides vaporisation are the highest in the case of cement plant II, where the highest amount of fluff is used that is one of the main sources of chloride.
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An investigation for energy sustainability in cement industries in Tanzania

An investigation for energy sustainability in cement industries in Tanzania

From literature sources, it can be concluded that, in general, there is a problem of sustainable energy use in cement industries, globally, owing to limitations imposed to technologies, ineffi‐ cient characteristic of equipment and processes as well as much reliance on fossil fuels. Other factors include, but not limited to, type of technology and raw materials used. However, there have been several efforts towards sustainable energy use in cement industries. Besides exist‐ ence of BAT for cement production processes, there is still room for further improvements based on individual cement plant assessment. Arguments furthering energy efficiency improve‐ ment measures are: It has been indicated in literature that fossil fuels like coal will still domi‐ nate cement production processes at least for the next few decades. This implies that there is crucial need to improve performance of cement plants to avoid losses that result into demand for more fuel burning and hence, higher cost of production and more CO 2 emissions. Further‐
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Carbon Capture for CO2 Emission Reduction in the Cement Industry in Germany

Carbon Capture for CO2 Emission Reduction in the Cement Industry in Germany

The Verein Deutscher Zementwerke (VDZ, German Cement Association) lists 22 companies that operate 53 cement plants in Germany [21]. Thirty-nine dry process cyclone preheater plants with a capacity of 0.1 Mt/d, as well as 6.7 kt/d of shaft kilns and grate preheater plants are in operation. Plants without clinker production are supplied with clinker and produce cement by means of clinker milling and blending with other raw materials. In Germany, 36% of the total clinker volume produced in 2014 was produced in a dry process with preheater and precalciner, 58% were produced in a dry process with preheater but without precalciner, and 7% were produced in a mixed process (dry/wet) [22].
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Modernization and innovation in the materials sector: Lessons from steel and cement

Modernization and innovation in the materials sector: Lessons from steel and cement

A variety of new low-carbon cement alternatives are be- ing investigated. Any such innovative low-carbon ce- ments are not expected to provide the very same func- tions as conventional cement. Instead they might be used—and possibly preferred—according to the rela- tive importance of soundproofing, different stability re- quirements, and fire protection. A further rationale for a more differentiated set of low-carbon cement types might emerge from the limited availability of resources, as few suitable materials are as accessible as limestone. Low-carbon cement options include “new” cements based on “old” ideas, such as calcium sulfoaluminate cement, clinker mineralization, as well as other new products. Cement sector executives argue that devel- oping and demonstrating such new products will take 10 to 15 years. Perhaps the most important barrier for product innovation is the absence of market demand for products with lower embedded carbon, especial- ly as long as carbon prices are low and not reflected in cement prices. Even with carbon prices included in ce- ment costs, it will take time, and the process of encour- aging users to make the shift to new cement types will be gradual: the use of cement and concrete for infra- structure with a very long lifetime, particularly foun- dations and buildings, makes proven durability of the cement a necessity.
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Metakaolin as an Additive in Composite Cement

Metakaolin as an Additive in Composite Cement

Before 1990, the compressive strength of reinforced concrete in Vietnamese constructions reached mainly 20 MPa and seldom 30 - 40 MPa. Nowadays, the compressive strength of reinforced concretes is mainly 30 MPa for normal building constructions and up to 60 MPa for special constructions. Very high compressive strength concrete (more than 100 MPa) has rarely been studied and applied for building constructions like bridge structures in Vietnam. Recently, the potential of manufacturing high performance concrete (60 – 80 MPa) in Vietnam has been addressed. Preliminary results confirmed that available materials in Vietnam can be successfully used for producing HPC [220]. Imported silica fume (from Elkem Silicon Material in Kingdom of Norway) and superplasticizer (Sika in Switzerland and MBT in Australia) facilitates the production of HPC and UHPC in Vietnam [221]. Recent studies have shown that Vietnamese rice husk ash can be applied to produce HPC and UHPC [222, 223]. However, the potential to use Vietnamese metakaolin for producing HPC has not been the subject of investigation. Therefore, in the present study, strength development was investigated not only for normal metakaolin mortars but also for high performance mortars with ca. 100 MPa. More recently within Vietman, there is the strong change of hydro-meteorologic for temperature from 7.3 to 42.2 o C [224, 225]. As such, different temperature treatments (8 – 20 - 40 0 C) have been used to prepare mortars. In order to effectively employ metakaolin in composite cement as well as to reduce the amount of Portland cement clinker to 55 Wt.-%, metakaolin is used in combination with calcite in different levels for the remaining 45 Wt.-%. This aim was to find an optimal combination of composite cement containing metakaolin and calcite, whereby the highest strength of mortar can be obtained. In addition to this, the properties of workability and porosity from selected mixtures were tested as shown in the following section.
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Nuclear Spin Relaxation and Water Self-diffusion in Hardening Magnesium Oxychloride Cement 

Nuclear Spin Relaxation and Water Self-diffusion in Hardening Magnesium Oxychloride Cement 

Fig. 4. Water self-diffusion coefficient, transverse relax­ ation time and signal amplitude as a function of the hard­ ening time in an Mg oxychloride cement paste. The fit of an exponential model to the diffusion coefficient decrease shows that the initial decrease is less pronounced than the one observed when the transverse relaxation time is already decreasing more slowly. The big scattering of the diffusion data at long hardening times is mainly due to the very poor signal available for the PFG experiment at these times.

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Fabrication and Characterization of Ice Templated Membrane Supports from Portland Cement

Fabrication and Characterization of Ice Templated Membrane Supports from Portland Cement

instance, several readily available raw materials, such as kaolin, fly ash, and rice husk ash-based silica, have been extensively used in the production of ceramic membranes [ 7 – 9 ]. However, these low-cost materials still require high-temperature sintering, i.e. >1000 ◦ C, despite the utilization of various sintering aids or processes like co-sintering [ 10 , 11 ]. To further decrease the production costs and environmental effects, the development of low-temperature or sintering-free membrane fabrication routes are still required. A comprehensive survey of preparing ceramic membranes from low-cost materials, such as clays, zeolites, apatite, bauxite, fly ash, rice husk ash, and cement is provided in our recently published review [ 6 ]. The fabrication of ceramic membranes from ashes, clays, apatite, and quartz sand needs relatively low sintering temperatures in comparison with alumina, zirconia, and titania, according to our survey. In contrast, cement-based membranes do not require sintering, and their fabrication is considered to be among the more cost-effective and environmentally friendly approaches to these systems.
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Relating Ettringite formation and rheological changes during the Initial cement hydration

Relating Ettringite formation and rheological changes during the Initial cement hydration

It should be taken into account that the results of the rheological measurements have to be scaled logarithmically to achieve a good correlation with the ettringite content, heat release and solid fraction of the paste, which are scaled linearly. Therefore, it can be assumed that the effect of ettringite precipitation on the rheological properties of the cement paste is of exponential order. With increasing ettringite content during hydration, the effect on the flow behavior becomes much larger. The ongoing water consumption of precipitating ettringite increases the solid fraction in the cement suspension and thus intensifys the interaction between particles. This exponential influence with increasing ettringite content can be modeled by applying the Krieger-Dougerthy equation [23]. Due to the lack of viscosity data, which were impossible to calculate with the applied geometry in this research, the measured torque to modeled viscosity relationship could not be defined. Nevertheless, this model could be used to explain the exponential effect of ettringite formation, which results in an increasing solid fraction, on the rheological properties of the paste, as shown in Figure 6.
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Einfluss der 3. Generationszementiertechnik auf das Auftreten des Bone Cement Implantation Syndrome bei der Implantation von zementierten Duokopfprothesen

Einfluss der 3. Generationszementiertechnik auf das Auftreten des Bone Cement Implantation Syndrome bei der Implantation von zementierten Duokopfprothesen

In  der  operativen  Versorgung  proximaler  Femurfrakturen  des  geriatrischen  Patien-­ ten   gilt   die   Implantation   einer   zementierten   Duokopfprothese   als   Verfahren   der   Wahl.  Durch  die  kürzere  Operationszeit,  den  geringeren  Blutverlust  und  die  besse-­ ren  frühfunktionalen  Ergebnisse  mit  einer  geringeren  Komplikationsrate,  ist  sie  der   Totalendoprothese  beim  älteren,   inaktiven   Menschen  überlegen.   Seit   der   Einfüh-­ rung  des  Knochenzements  durch  John  Charnley  im  Jahr  1961  entwickelte  sich  die   Technik   des   Zementierungsvorganges   stetig  weiter,   sodass   heute   das   Verfahren   der  3.  Generationstechnik  als  Goldstandard  angesehen  wird.  Bereits  seit  der  Ein-­ führung  der  Zementierung  konnten  kardiorespiratorische  Veränderungen  beobach-­ tet   werden,   welche   unter   dem   Begriff   des   Bone   Cement   Implantation   Syndrome   (BCIS)   in   der   Literatur   geführt   werden.   Während   sich   zahlreiche   Studien   bislang   mit   dem   allgemeinen   Auftreten   des   BCIS,   dessen   Genese   und   Pathophysiologie   beschäftigten,  war  es  Ziel  der  vorliegenden  Studie,  einen  Vergleich  zwischen  der   2.  und  3.  Generationszementiertechnik  bezüglich  der  Häufigkeit  des  BCIS  durch-­ zuführen.   Dabei   galt   es   mögliche   Vorteile   des   modernen   Verfahrens   im   Hinblick   auf  die  Reduktion  des  BCIS  zu  erkennen,  um  diese  für  zukünftige  Eingriffe  nutzen   zu  können.    
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Atmospheric Extenction in Solar Tower Plants

Atmospheric Extenction in Solar Tower Plants

Simulate spectral DNI at ground level using input of temperature, pressure, relative humidity and AOD from AERONET and particle counter. Simulate radiative transfer of photons through a[r]

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Investigating the release of ZnO nanoparticles from cement mortars on microbiological models

Investigating the release of ZnO nanoparticles from cement mortars on microbiological models

Incorporating zinc oxide nanoparticles (ZnO NPs) into cement mortars may provide additional functions, e.g., self-cleaning and antibacterial or electroconductive ability. However, these NPs are also known for their potential toxicity. During the life cycle of a cement mortar, various abrasive forces cause the release of admixtures to the natural environment. The effect of the released NPs on model microorganisms has not been extensively studied. Previous studies have shown that nanomaterials may affect various microorganisms’ physiological responses, including changes in metabolic activity, biofilming, or growth rate. In this study, we have focused on evaluating the response of model microorganisms, Escherichia coli, Pseudomonas
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Antibodies from plants for bionanomaterials

Antibodies from plants for bionanomaterials

A pledge for plant-derived antibodies Plants can make antibodies! And they can make them efficiently and in all kinds of formats. ŽŶ͛ƚďĞ afraid to use plants to make antibodies and bionanomaterials. /ƚ͛Ɛeasy, inexpensive and requires only basic laboratory skills. Plant-based production systems come in many flavors and scales, and are equally well suited to the high-tech environments of industrialized countries and the resource-poor settings of developing nations. Yes, there are still challenges and bottlenecks ahead, making research and development just as interesting as the diverse applications. But among the currently available expression systems, plants are probably the most versatile, globally accessible and possibly the most sustainable. Antibody diversity embraces not thousands but millions or even billions of different structures, providing an almost infinite source of structural and functional components for diverse applications, including the development of bionanomaterials and bionanomedicines. So ůĞƚ͛Ɛ explore! All it takes is basic recombinant DNA technology, the help of a little soil bacterium and a green thumb. The rest is just sun, soil and water.
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Parasitic Angiosperms as medicinal plants

Parasitic Angiosperms as medicinal plants

6 th International Symposium Breeding Research on Medicinal and Aromatic Plants, BREEDMAP 6, Quedlinburg, Germany, June 19-23, 2016 66 Julius-Kühn-Archiv, 453, 2016 ESL 5: Parasitic Angiosperms as medicinal plants Karl Hammer 1 , Merita Hammer-Spahillari 2

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Effects of strontium loaded calcium phosphate cement on osteoporotic fracture defect healing

Effects of strontium loaded calcium phosphate cement on osteoporotic fracture defect healing

45 female Sprague-Dawley rats were randomly assigned to three different groups: (1) strontium modified calcium phosphate cement (SrCPC), (2) calcium phosphate cement (CPC) and (3) empty defect control group. The animals underwent induction of osteopenic bone status by bilateral ovariectomy combined with a multi-deficient diet as described later (3.5.1). A critical size defect of 4mm was then created in the metaphysis of these rats which were subsequently filled with SrCPC, CPC implant material in the metaphyseal region of the osteoporotic rat femur (Fig. 8), was used to study the effects of strontium loaded implants on bone remodeling. A control group with a critical size metaphyseal defect, without biomaterial implant was compared with test groups consisting of CPC and SrCPC respectively. Resulting bone formation was investigated using histomorphometry, immunohistochemistry, molecular biology and TOF-SIMS analysis. The TOF-SIMS analysis was carried out as a collaboration work with the Institute for Physical Chemistry, Justus-Liebig-University of Giessen. All interventions were performed in full compliance with the institutional and German protection laws and approved by the local animal welfare committee (Reference number: V 54 – 19 c 20-15 (1) GI 20/28 Nr. 108/2011).
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