Academic literature on the topic 'Cement Plant AFR'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Cement Plant AFR.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Cement Plant AFR"
1
Benlamoudi, Ali, Aeslina Abdul Kadir, and Mohamed Khodja. "Incorporation of Alternative Fuels and Raw Materials (AFR) to Produce a Sustainable Cement." International Journal of Engineering & Technology 7, no. 4.30 (November 30, 2018): 136. http://dx.doi.org/10.14419/ijet.v7i4.30.22079.
Full textAbstract:
Throughout the last two decades, tremendous researches have been carried out to investigate the possibility to reduce the cement plants’ costs in terms of raw materials and fuel consumption. Different types of alternative fuels and raw materials (AFR) have been used and proved their efficiencies such as sewage sludge, used tires, crushed aggregates, refuse derived fuel (RDF), red mud, ash and others. Generally, it has been deduced that the possibility to incorporate AFR to produce an acceptable quality of cement is related mainly to its calorific value and its chemical composition. As results, it was reported that incorporation of AFR has reached up to 100% for raw materials substitution and more than 30% for fossil fuel replacement. Nevertheless, the AFR may contain toxic components such as volatile content and heavy metals that need careful attention in its decisive use since it may pose serious problems to the environment and the living things. More parameters may affect the cement production cost including the moisture content of AFR, the burning temperature, the residential time, the accessibility to the AFR, the easy handling and others. The high moisture content of the AFR may increase the total cost of cement production because of the need of a high thermal energy to dry it prior to be incorporated into cement plant. Same thing goes with temperature needed by the AFR to be burned within the kiln. This overview summarizes the studies throughout the last two decades related to cement manufacturing by using AFR based on the main parameters studied by the researchers, the main advantages and the main disadvantages.
2
Bumanis, Girts, Diana Bajare, and Aleksandrs Korjakins. "Durability of High Strength Self Compacting Concrete with Metakaolin Containing Waste." Key Engineering Materials 674 (January 2016): 65–70. http://dx.doi.org/10.4028/www.scientific.net/kem.674.65.
Full textAbstract:
Metakaolin is considered as one of most promising pozzolanic microfiller material in concrete industry. Metakaolin is a high value product obtained from kaolin clay calcined at high temperatures which also can be effectively used in ceramic industry therefore its application in concrete industry is rather limited. In present research metakaolin containing waste (MKW) by-product was studied as a partial cement replacement in high strength self compacting concrete (SCC). Obtained waste material derives from the foam glass granule production plant where kaolin clay is used as releasing agent during heating process and in the end metakaolin with glass impurities is obtained as by-product. In present research 5 to 15 wt.% of cement was replaced by MKW. A constant water amount was used for all mixtures and workability (>600 mm by cone flow) was ensured by changing the amount of superplasticizer. Compressive strength was tested at the age of 7, 28 and 180 days. To determine durability of SCC the chloride penetration was tested according to NT BUILD 492, freeze-thaw test according to LVS 156-1:2009 annex C and alkali-silica reactivity test according to RILEM TC 106-AAR-2. The results indicate that cement replacement by MKW did not affect the strength of SCC significantly. At the age of 28 days SCC with 15 wt.% of MKW reached compressive strength of 70 MPa comparing to 68 MPa to reference mixture. The chloride penetration test results indicated that the non-steady-state migration coefficient of reference samples was reduced 3.7 times and it was concluded that SCC resistance to chloride penetration can be increased by incorporation of MKW in mixture composition. Freeze-thaw test results indicated that obtained SCC can withstand at least 500 freeze-thaw cycles without surface damage and weight loss. It was concluded that up to 15 wt.% of cement can be replaced by metakaolin containing waste without strength loss and the durability of SCC could be increased.
3
Olasumbo, Olayinka O., Adedeji O. Hakeem, Oresanya O. Juwon, and Alabi-Thompson O. Francisca. "Environmental and Health Impact of Cement Factory Production in Ibese, Ogun state, Nigeria." Applied Environmental Research, August 15, 2016, 93–110. http://dx.doi.org/10.35762/aer.2016.38.2.8.
Full textAbstract:
This study investigated the effect of cement dust emitted from Dangote cement factory, Ibese, Ogun State, Nigeria on the environment and human health. Soil and plant samples were col-lected from six sampling points at different distances i.e. inside the factory kiln (IFK), the factory 300m), based on the prevailing wind direction. Control samples were taken opposite the wind direction at ILA(Ilaro) about 1,000 m. Cu, Zn, Mn, Pb, Ni and Cd were analyzed in the samples using atomic ab-sorption spectrophotometer. Air quality and noise levels were monitored using standard me-thods. Sulphur dioxide, oxides of nitrogen (NOx), total suspended particulate matter and noiseconcentrations ranged from 7-25ppm, 0.1-0.2ppm, 101-13,056ugm-3and 72.1-98.2dBrespec-tively,which were higher than USEPA standard. Heavy metals in soils were in the order of: MAR>IFK>AOK>IBE>ILA>TFG for Cu, AOK>MAR>IFK>TFG>ILA>IBE for Zn, IBE>IFK>MAR>AOK>TFG>ILA for Cd, IBE>AOK>MAR>TFG>IFK>ILA for Mn, IBE>AOK> TFG>MAR>ILA>IFK>IBE for Pband MAR>TFG>AOK>IBE>ILA>IFK for Ni. Health-related characteristics of the respondents also showed that 2.5% had allergies that hindered breathing, while 3.75% had difficulty in smelling. Health risk assessment showed that in-gestion is the major pathway of exposure to heavy metals in soil samples for both children andadults. Cd, Mn, Ni and Pb pose non-cancer risks to children, while only Cd and Mn pose non-cancer risks to adults. Ni and Pb pose the greatest cancer risk to children. In cassava leaves andtubers Pb was the only metal found to pose cancer risk in both children and adults.
Dissertations / Theses on the topic "Cement Plant AFR"
1
Micheli, Paola. "Assessment of available technologies for treatment of drilling cuttings considering economical and geographical conditions." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Find full textAbstract:
The aim of the thesis is to outline why hydrocarbons still so important nowadays and how to manage the environmental impact in a sustainable way, in particular the management and disposal of the waste stream of drilling cuttings.
The paper present the importance of the Oil and Gas sector, the petroleum generation, the Oil and Gas exploitation and production and the waste stream generated by it with a particular focus on drilling muds and drilling cuttings.
An analysis among the different types drilling muds (i.e. drilling fluids) in particular on the oil-based (OBM) one has been performed because of the important environmental impact and the consequently waste management needed. Among the different possible technologies have been analyzed in detail the more reliable one according with the economical, legal and environmental constrains. The chosen technologies are Solidification/Stabilization (S/S), Composting (bio-pile technology), Thermal desorption, Cement Plant AFR (Alternative Fuels and Raw Materials and Eko/grid technology.
A business plan has been implemented to understand which one between those technologies is the more suitable in some possible different scenarios where the main driver take in account are local actual economical, social and political situation, law limits, logistic and duration of the project
Ten different cases have been studied, two different scenarios for each of the five chosen technologies.
The two different chosen scenarios are Europe and North Africa
The results presented shall be taken as an exercise the demonstrate how to approach a new business in the field of Drilling Waste Management (DWM) and calculate a DWM Company start-up costs and finance required and a basic P&L (Profit & Loss).
The business plan model in the way has been implemented can be used to assess quickly the convenience of one technology with respect another for a Start Up company or can be a tool used for assessing a new investment linked to a project.
Books on the topic "Cement Plant AFR"
1
India. Central Pollution Control Board., ed. Assessment of fugitive emissions & development of environmental guidelines for control of fugitive emissions in cement manufacturing industries. New Delhi: Central Pollution Control Board, Ministry of Environment & Forests, 2007.
Find full text
2
United States. Congress. House. Committee on Government Operations. Environment, Energy, and Natural Resources Subcommittee, ed. Environmental protection: EPA's plans to improve longstanding information resources management problems : report to the Chairman, Environment, Energy, and Natural Resources Subcommittee, Committee on Government Operations, House of Representatives. Washington, D.C: The Office, 1993.
Find full textBook chapters on the topic "Cement Plant AFR"
1
Deolalkar, S. P. "Problems with Using AFs." In Designing Green Cement Plants, 129–31. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-803420-0.00019-6.
Full text
2
Deolalkar, S. P. "Properties of Commonly Available AFs." In Designing Green Cement Plants, 71–77. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-803420-0.00009-3.
Full text
3
Deolalkar, S. P. "Possibilities of Using AFs in Cement Plants." In Designing Green Cement Plants, 83–86. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-803420-0.00011-1.
Full text
4
Deolalkar, S. P. "Procurement, Processing, Storage, and Transport of AFs." In Designing Green Cement Plants, 87–93. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-803420-0.00012-3.
Full textConference papers on the topic "Cement Plant AFR"
1
Hansen, Mogens Weel, and Jan Sandvig Nielsen. "Optimal Integration of Humid Air Cycle in Energy Intensive Industries." In ASME 1996 Turbo Asia Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-ta-049.
Full textAbstract:
Humid Air Turbine cycle (HAT) is characterised by its high single cycle efficiency. The HAT cycle is typically constrained by a pinch point at low temperature. This indicates that additional heat in the range 100 °C to 200 °C can be utilised with high marginal efficiency. At the same time energy intensive industries (for example refineries, Cement production plants and Steel works) typically have a surplus of heat from around 250 °C to 300 °C and down. This study is aimed at the integration of HAT Cycle into the industrial process plant where the complementary features can be exploited. The present paper has two main objectives. The first objective is to present a general approach for integration analysis. The approach is based on conceptual design using targeting procedures (e.g. Pinch Analysis). The second objective is to find an optimum integration scheme for specific heat sources available from industrial sites. To illustrate both objectives a case study based on real refinery data is discussed.
2
Lilian, Simiyu E., and Sandra Konez. "Innovations in Carbon (iv) Oxide Capture and Sequestration for Operations, Engineering and Technology." In SPE/AAPG Africa Energy and Technology Conference. SPE, 2016. http://dx.doi.org/10.2118/afrc-2572863-ms.
Full textAbstract:
ABSTRACT Fossil fuel combustion supplies more than 85% of energy for industrial activities and thus it is the main source of greenhouse gases in the form of CO2. This is expected to remain unchanged for a long time as the world energy consumption doubles. Renewable energy is often a better option since it is environmental friendly but its technologies are not financially available for most countries. Carbon (iv)oxide capture and sequestration (CCS) is necessary for meaningful greenhouse gases reduction in the immediate future. CCS could reduce emissions by 19%. This is an important bridge between our lifestyle and an environmental friendly world. The components of CCS system include; capture (separation and compression), transport, injection and finally monitoring. Power plants which are gas and coal fired are the main source of CO2. Other candidate sources include; cement production plants, refineries, petrochemical industries, oil and gas processing firms and natural gas wells The methods of capturing CO2 are pre-combustion, post-combustion and oxy-combustion/oxy-fuel. Possible sequestration places for the captured CO2 include; geological storage, for example depleted oil and gas reservoir, enhanced oil recovery, un-minable coal seams and deep saline formations, ocean storage, mineral carbonation and algal growth. Each of the methods above have their advantages and shortcomings as discussed in the research paper. CO2 can be utilized in various ways like, conversion into renewable fuels, formic acid, syngas, methane and methanol, utilizing CO2 as a feedstock for organic and inorganic carbonates, urea and biodegradable polymers as well as non-conversion use of CO2 for example as a geothermal fluid, used in enhanced oil recovery and beverage making. The challenges of CCS are; high cost of capture transport and injection, environmental and safety, subsurface uncertainty, legal and regulatory issues. Trappings contribute to storage of CO2 in a site. They include; Structural and stratigraphic, residual, solubility, mineral trappings. In conclusion, an approach that integrates different methods of capture and storage of CO2 may be a practical solution for CCS.
3
Raju, Thushara, Namitha S, Muhammed Nabil K, Mohammed Rafeeque N. V, Reshma Sundhar, Ramaswamy K. P, and Saraswathy B. "Effect of alkali content and slag content on the fresh and hardened properties of air-cured alkali activated mortar containing fly ash." In International Web Conference in Civil Engineering for a Sustainable Planet. AIJR Publisher, 2021. http://dx.doi.org/10.21467/proceedings.112.48.
Full textAbstract:
Alkali Activated Material (AAM) is introduced as a pioneering construction material in the construction diligence to trim down the utilization of Ordinary Portland Cement (OPC) and to curtail the amount of carbon dioxide released during the production of OPC. Modestly refined industrial by products or natural materials rich in alumino silicates are the binding agents used in AAM. Generally, heat curing is needed for the alkali activated mortar to achieve the required hardened properties and this difficulty can be overcome by adding slag to the mix. In this experimental analysis, the alkali activated mortar mixes with different proportions of glassy granulated slag and Class F fly ash were prepared without the usage of superplasticizers, with alkali to binder (a/b) ratios of 0.7, 0.8 and 0.9. The rheological characteristics of mortar were studied using flow table apparatus and hardened properties were studied using compressive strength test and ultrasonic pulse velocity (UPV) test by testing cylindrical specimens of size 25 mm diameter and 50 mm height. The mortar specimens were air-cured, and the compressive strength and UPV test were conducted after 3 and 7 days. The test results showed that due to the presence of higher alkali content and the decrease in slag content, the workability of alkali activated mortar was improved, but the measure of strength decreased. The mix with 100% slag and a/b ratio of 0.8 had the best UPV value, indicating its quality among the various mortar mixes studied. This study portrays the significance of optimising the alkali and slag content in tailor making an alkali activated mortar system with good hardened properties.
4
Kitamura, Koichi, Hirokazu Hayashi, Mitsumori Shimizu, Kiyoshi Matsuo, Haruyuki Namba, and Kazuo Murakami. "Development of Decontamination Method for the Concrete Contaminated With C-14 Nuclide in Fugen." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48602.
Full textAbstract:
Planning and preparation on decommissioning of the Fugen Nuclear Power Plant have been carried out, and it is one of the most important issues to reduce amount of the radioactive waste for decreasing the disposal cost of them in the dismantling process. In Fugen, the concrete of the reactor building is contaminated with C-14 that was generated due to the activation of CO2 gas during the plant operation. In this study, concrete samples were taken from the reactor building to survey how C-14 is penetrated into the concrete. Concentration of C-14 and C-14 existing rate in each element of the sample specimens were measured in order to investigate C-14 existing feature in the concrete. Besides, depth of the neutralization was measured in order to study on potential relationship with penetration of C-14. Then the following results were obtained: (1) C-14 is penetrated deep beneath of the surface, the depth is approximately as deep as 250mm. (2) C-14 exists only in cement portion of the concrete. It does not exist in aggregates. (3) Analytical study showed that CO2 gas containing C-14 could be penetrated into deeper position in hot and dried air condition during reactor operation, which is coming from that CO2 gas penetrating into concrete tend to move faster in void portion of the porous concrete than in liquid portion of that. Possible methods for removal of C-14 from the concrete are studied based on the above findings. This study showed that C-14 is localized in confined cement portion in 250mm depth of concrete. It is also cleared that CO2 gas containing C-14 in concrete could be removed by heating at a particular temperature. Therefore, it is expected that almost C-14 could be removed from concrete using the combination of both separating of cement portion and heating of it. In the next step of this study, planning the practical procedure for dismantling the reactor building and the removal and disposal method of C-14 will be carried out on the basis of the results of this study. The widely measurement with sampling more specimens is also planned in order to investigate C-14 contaminated distribution of the whole reactor building.
5
Benvenuti, Erio, and Marco Sargenti. "The PGT2, a New 2-MW Class Efficient Gas Turbine: Applications and Operating Experience in Cogeneration." In ASME 1996 Turbo Asia Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-ta-028.
Full textAbstract:
The PGT2 is a single-shaft gas turbine with a 2 MW ISO electric output that, after an extensive factory development program has been launched into industrial service with a number of cogeneration applications in small-medium size industries. The two-stage high pressure ratio compressor combined with the single-can combustor and the two-stage air-cooled transonic turbine provides a compact and rugged architecture. The turbine inlet temperature in the 1050–1100 °C class and the 12.5:1 pressure ratio provide a 25% electrical efficiency and a high exhaust temperature that make this machine attractive for a variety of both civil and industrial applications like hospitals and pulp and paper mills, textile, tiles, cement, glass and food production. The exhaust heat recovery boiler can be either a commercial unit or compact once-through type of proprietary design that is housed in a vertical exhaust duct to substantially reduce powerplant footprint area when space is limited. The first application that has provided the most extensive operating experience so far is cogeneration in a paper mill in central Italy. Detailed studies on the potential energy saving and on the return of investment cycle were made in collaboration with the client, and provided a valuable basis for further studies that led to additional orders for paper mills, textile and tile industries. The first installed unit is a package comprising a once-through-flow boiler that was full-load tested at the factory before shipping. Commissioning of the cogeneration plant was started in 30 days after shipment and the plant was taken over by the client in less than three months. A dedicated telephone line allows the power plant to be monitored directly from Florence, thus making it possible to gather operational data in real time and to provide this first customer with prompt assistance during the 4-year service and maintenance contract period. This paper describes the PGT2 design and performance features, the technical and economic evaluations made for the first application, the cogeneration plant layout and a summary of the most significant operational data collected in the initial months or regular service in the paper mill.
6
Mulch, Stephan. "Boiler Wall Protection With Rear Ventilated Refractory Tiles." In 2013 21st Annual North American Waste-to-Energy Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/nawtec21-2703.
Full textAbstract:
The prevention of corrosion on boiler tube-walls has been a most difficult and cost intensive problem in WTE plants. This is specifically the case where the incineration boilers are operating with increased saturated steam temperatures and their corresponding pressures. In addition, variations in the garbage mixtures, with differing values of chemical content and varying waste composition give importance to the prevention of boiler tube corrosion. Several refractory lining systems and types have been installed over the previous 80 years and can be compared. In the early stages it began with simple concrete installations and only later was it developed to use heat resistant ceramic products, now essentially silicon carbide. 20 years ago cement or chemically bonded SiC monolithics (gunning, trowelling or casting materials) were usually installed to protect boiler walls, but today fabricated and fired SiC tiles, with their enhanced properties, are mainly used. A distinction is made between hanging and bolted tiles, as well as between oxide bonded and nitride bonded SiC material and between mortared, backfilled and rear ventilated tiles. All these systems were carefully examined and assessed. It proved possible to develop a revolutionary heat conduction and corrosion protection system utilising air. An air gap between the refractory SiC tiles and the boiler wall proved to be both simple and successful. By means of detailed and systematic documentation and monitoring, including J + G’ s “Air” tiling system, it has, for a few years, been possible to offer and recommend long lasting refractory linings with the aim of protecting boiler walls against corrosion, reducing operating costs and using the energy of the waste in an optimum manner.
7
Cardoe, Jennifer, Gunnar Nygaard, Christopher Lane, Tero Saarno, and Marc Bird. "Oil and Gas Drill Bit Technology and Drilling Application Engineering Saves 77 Drilling Days on the World’s Deepest Engineered Geothermal Systems EGS Wells." In SPE/IADC International Drilling Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204121-ms.
Full textAbstract:
Abstract An Engineered Geothermal System (EGS) pilot project was commissioned to prove the economic viability of an industrial scale geothermal heat plant in Finland. The project aims to generate 40 MW of emission free heat energy, supplying up to 10% of the city of Espoo’s district heating needs. Two wells of 6400 m MD and 6213 m MD (measured depth) were drilled through formations of hard, abrasive granitic gneiss with maximum measured 560 MPa UCS (unconfined compressive strength). Typical dull conditions of lost and worn cutting structure and gauge diameter wear of between 3/16-in to ¼-in contributed to excessive torque, stuck incidences, low rate of penetration (ROP) and difficulties achieving build rate. To address these drilling challenges, this paper explores the interplay between new cemented carbide compact technology, drill bit design, and drilling parameter road mapping. The directional section of the first well was drilled with an average ROP below 2 m/hr and run length averaging 56 m per bit. The well took 246 drilling days and 44 BHAs (bottom hole assemblies) to achieve TD (total depth). Between the first and second well an application specific drill bit design package and step-wise parameter program were implemented. Design enhancements included improved gauge protection, bit hydraulics for minimizing cone erosion and subsequent TCI (tungsten carbide insert) compact loss. Novel hybrid TCI materials technology was introduced having a 100% improvement in wear resistance and durability as compared with conventional grades, to drill these hard and abrasive granitic formations. New BHAs and drilling plan were selected based on the bit design selection to reduce wear on BHA components, improve directional control and reducing drilling dysfunctions. Once these factors were under control, a low risk approach to extending the bit revolution limits (krev) for the roller cone sealed bearings could be implemented based on downhole parameters and previous bit dulls, leading to longer run lengths. The combination of bit design and material enhancements with a properly selected BHA and drill plan increased run lengths and ROP. The second well’s 8.5-in directional section was drilled with a 13% increase in average ROP and a 69% increase in average run length without exceeding krev limits. Well on well, a 77 day reduction in AFE (authorization for expenditure) was realized. We demonstrated the combination of oil and gas bit and BHA design, drilling plan, and new cutting material capabilities can reduce EGS well construction costs in order to make these renewable energy sources economical.
8
Cepraga, D. G., G. Cambi, M. Frisoni, and D. Ene. "Cemented Containers Radiological Data From a Disused Uranium Mine Low-Level Waste Repository: A Calculated-Experiment Cross-Check for Data Verification and Validation." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4516.
Full textAbstract:
Code validation problems involve calculation of experiments and a comparison experiment-calculation. Experimental data and physical properties of these systems are used to determine the range of applicability of the validation. Once a sequence-code of calculations has been validated, it has to be underlined that the comparison experimental-calculated results involving “complex systems” or “complex experimental measures” permits also a bi-lateral cross-check between the calculation scheme and the experimental procedures. The results of the testing and the validation effort related to the collection of information and measured data and the comparison between code results with experimental data coming from a “low-level waste” repository are presented in this paper. The Baita-Bihor repository, sited into former disused uranium mine in Transylvania, has been considered as the source of experimental data. The study was developed through the following steps: a) collection and processing of measured data (radioactivity content and dose rate), from the cemented containers of the Baita-Bihor repository; b) decay gamma source calculation by the ANITA-2000 code package (the input data for the calculations are the measured isotope activities for each container); c) decay gamma transport calculation by the SCALENEA-1 shielding Sn sequence approach (Nitawl-Xsdrnpm-Xsdose modules of the Scale 4.4a code system, using the Vitenea-J library, based on FENDL/E-2 data) to obtain dose rates on the surfaces and at various points outside the containers; d) comparison experimental-calculated dose rates, taking into account also the measurement uncertainties. The new version of the ANITA-2000 activation code package used makes possible to assess the behaviour of irradiated materials independently from the knowledge of the irradiation scenario but using only data on the isotope radioactive material composition. Radioactive waste disposed of at Baita Bihor repository consists of worn reactor parts, resins and filters, packing materials, mop heads, protective clothing, temporary floor coverings and tools, the sources normally generated during the day-to-day operation of research reactors, the remediation-treatment stations and the medicine and biological activities. The low and intermediate wastes are prepared for shipping and disposal in the treatment stations by confining them in a cement matrix inside 220 litre metallic drums. Each container consists of an iron cladding filled by concrete Portland. Radioisotope composition and radioactivity distributions inside the drum are measured. The gamma spectroscopy has been used for. The calibration technique was based on the assumption of a uniform distribution of the source activity in the drum and also of a uniform sample matrix. Dose rate measurements are done continuously, circularly, in the central plan on the surface of the drum and 1 m from the surface, in the air. A “stuffing factor” model has been adopted to simulate, for the calculation, the spatial distribution of the gamma sources in the concrete region. In order to guarantee a complete Quality Assurance for codes and procedures, a simulation of the radioactive containers to evaluate the dose rates was done also by using the Monte Carlo MCNP-4C code. Its calculation results are in a very good agreement with those obtained by the Sn approach (discrepancies are around 2%, using the spherical approximation).
9
Hii, N. C., S. J. Wilcox, A. Z. S. Chong, J. Ward, and C. K. Tan. "The Application of Acoustic Emission to Monitor Pulverised Fuel Flows." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80912.
Full textAbstract:
There are a large number of industrial processes involving the transport of pneumatically conveyed solid including mineral processing, electrical power generation, steel and cement production. For coal-fired power plant, in particular, pulverised fuel (pf) is fed by pneumatic means where coal particles are transported by the primary air from each mill directly into furnace. The distribution of coal particles to each burner bank is normally split mechanically from larger pipelines into a smaller network of pipes connected to each of the burners. Despite the use of matched outlet pipes and riffle devices within the splitters, uneven distribution of the pulverised coal inevitably occurs. Incomplete combustion due to the non-uniform distribution of the pulverised coal between the burner\u2019s feed pipes leads to a reduction in boiler efficiency. This also directly leads to an increase in slagging and fouling in the burner and increased NOx emission from the burner. Measuring can solve this problem and subsequently controlling the mass flow in each burner feed pipe and then adjusting the excess air to operate near the minimum. Over the past ten years or so, there has been increased interest in applying acoustic emission (AE) detection methods for process condition monitoring. The European Working Group for Acoustic Emission (EWGAE), 1985, defines AE as ‘the transient elastic waves resulting from local internal micro displacements in a material’. The American National Standards Institute defines AE as ‘the class of phenomena whereby transient elastic waves are generated by a rapid release of energy from a localised source or sources within a material, or the transient elastic waves so generated’. Therefore, in principle, any impulsive and energy release mechanism within a solid or on its surface, such as plastic deformation, impact, cracking, turbulence, combustion, and fluid disturbances, is capable of generating. Since these mechanisms can be associated with the degradation occurring within a particular process, it follows that AE has great potential in condition monitoring, for example, monitoring of tool wear, corrosion and process monitoring of the pneumatically conveyed solid. Unlike most of the other techniques, AE sensors are non-invasive so that their interruption with the flow within the pipe can be totally avoided. Furthermore, the frequency responses of AE sensors are normally very high (in the order of a Mega Hertz) so that they are immune to low-frequency environmental noises. The use of AE detection techniques is appropriate in this project since the frictional contacts between the flowing particles and the inner wall of the conveying pipe can effectively generate ‘elastic waves’ which propagate through the inner pipe wall and be detected by an AE sensor attached to the outer pipe wall. Consequently, the current research work aims to demonstrate the use of an AE to monitor the flow of particles in a conveying pipe. Preliminary results indicate that AE is generated and is highly repeatable for both variations in velocity for a fixed particle size and also for variations in mass flow rate at a fixed velocity.