scholarly journals Portland Versus Alkaline Cement: Continuity or Clean Break: “A Key Decision for Global Sustainability”

2021 ◽  
Vol 9 ◽  
Author(s):  
A. Palomo ◽  
O. Maltseva ◽  
I. Garcia-Lodeiro ◽  
A. Fernández-Jiménez
Keyword(s):  
Scientific Community ◽  
Large Scale ◽  
Raw Materials ◽  
Industrial Process ◽  
Scale Production ◽  
Low Carbon ◽  
Commercial Development ◽  
Scientific Papers ◽  
Clean Break ◽  
Alkali Activated Binders

This review undertakes rigorous analysis of much of the copious literature available to the scientific community on the use of alkali-activated binders (AABs) in construction. The authors’ main intention is to categorically refute arguments of that part of the scientific community underestimating or even dismissing the actual potential of AABs as alternatives to Portland cement (PC). The main premise invoked in support of those arguments is a presumed lack of material resources for precursors that would make AAB industrial-scale production unfeasible anywhere on the planet (a substantial number of scientific papers show that the raw materials required for AAB manufacture are in abundance worldwide). The review also analyses the role of alkaline activators in the chemistry of AABs; it is important to clarify and highlight that alkaline activators are not, by any means, confined to the two synthetic products (caustic soda and waterglass) mostly employed by researchers; other sustainable and efficient products are widely available. Finally, the review deals with the versatility of AAB production processes. The technologies required for the large scale manufacturing of AABs are mostly already in place in PC factories; actually no huge investment is required to transform a PC plant in a AAB factory; and quality and compositional uniformity of Alkaline Cements (binders produced through an industrial process) would be guaranteed. The last conclusions extracted from this review-paper are related with: i) the low carbon footprint of one-part AABs and ii) the urgent need of exploring standardization formulas allowing the commercial development of (sustainable) binders different from PC.

Optimal Design and Techno-Economic Analysis for Corncob Particles Briquettes: A Literature Review of the Utilization of Agricultural Waste and Analysis Calculation

2021 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Nissa Nur Azizah ◽  
Gabriela Chelvina Santiuly Girsang
Keyword(s):  
Optimal Design ◽  
Literature Review ◽  
Economic Analysis ◽  
Large Scale ◽  
Net Present Value ◽  
Raw Materials ◽  
Agricultural Waste ◽  
Raw Material ◽  
Variable Cost ◽  
Scale Production

Corncob is usually disposed of directly as waste, creating problems in the environment, while it can be converted into valuable materials. This research aimed to evaluate the literature review on briquette production from agricultural waste (using non-binder and cold press with a binder) and the current works on techno-economic analysis, to propose an optimal design for the production of briquette from corncob waste, and to perform a techno-economic analysis based on the selected optimal processing method. The engineering perspective based on stoichiometry and mass balance showed the potential corncob briquette manufacture in both home and large scales due to the possible use of inexpensive and commercially available equipment and raw materials. The economic perspective [based on several economic evaluation factors (i.e., gross profit margin, payback period, break-even point, cumulative net present value, return of investment, internal rate return, and profitability index) under ideal and non-ideal conditions by considering internal (i.e., sales, raw materials, utilities, and variable cost) and external aspects (i.e., tax)] confirmed the prospective development of the project in the large-scale production with a lifetime of more than 18 years. The main issue in the project is the raw material (i.e. tapioca flour), giving the most impact on the project’s feasibility. Even in severe conditions, the project is feasible. The great endurance was also confirmed in the case of a higher tax rate. This study demonstrates the importance of producing corncob-based briquettes for improving the economic value and giving alternatives for problem solvers in the utilization of agricultural waste.

An Improved And Suitable Method For Large Scale Produdcion Of Α-Monochlorocyclodecanone

2021 ◽  
Vol 18 ◽  
Author(s):  
Wenhua Ou ◽  
Ruolin Wang ◽  
Ruonan Liu ◽  
Hong Huang
Keyword(s):  
Silica Gel ◽  
Large Scale ◽  
Raw Materials ◽  
Separation Method ◽  
Suitable Method ◽  
Scale Production ◽  
Reaction Conditions ◽  
Environment Friendly ◽  
Large Scale Production ◽  
Ideal Approach

: α-Monochlorocyclododecanone was synthesized from cyclododecane and 1,3-Dichloro-5,5-dimethylhydantoin (DCDMH) catalyzed with silica gel in MeOH. The product was obtained by crystallization with nearly 85% yield. The presented method used cheap raw materials, mild reaction conditions, simple separation method and environment-friendly process. Additionally, the current synthesis provided an ideal approach for large-scale production.

Strength and Impotence. The Developing Countries and the Development in New Territories

1974 ◽  
Vol 9 (2-3) ◽  
pp. 167-177
Author(s):  
Willy Østreng
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Developed Countries ◽  
Economic Effects ◽  
Scale Production ◽  
Underdeveloped Countries ◽  
The North ◽  
Large Scale Production ◽  
The Developed Countries ◽  
The Third World

This article examines the possible political and economic effects of large-scale mineral extraction from the seabed. The findings presented indicate that development in new territories may conceivably serve to exacerbate existing conflict dimensions, notably the North/South dimension in global politics. Because of the developed countries' monopoly on know-how and economic capability, exploration and exploitation of the inorganic resources of the ocean floor has de facto been the exclusive domain of these countries. On the basis of this the author shows that if large-scale production of seabed resources should become a reality in the near future, the underdeveloped countries will be forced to watch it from the sidelines. As a consequence, the exploitation of offshore raw materials will probably contribute to the further widening of the gap between developed and underdeveloped countries. Further commenting on the fact that the latter today are the main producers of the most promising seabed resources, the author expresses the view that exploitation will have a detrimental effect on the economics of the Third World countries, since it might lead to overproduction and price reductions.

Technologies of Nanomodification of Low-Carbon Low Alloyed Steels

2010 ◽  
Vol 638-642 ◽  
pp. 3123-3127
Author(s):  
V.A. Malyshevsky ◽  
E.I. Khlusova ◽  
V.V. Orlov
Keyword(s):  
Large Scale ◽  
Physical And Mechanical Properties ◽  
Metallurgical Industry ◽  
Low Alloy Steels ◽  
Scale Production ◽  
Low Carbon ◽  
Fine Grained ◽  
Interphase Boundaries ◽  
Alloy Steels ◽  
High Level

Metallurgical industry can be considered as a field most accommodated for perception of nano-technologies, which in the near future will be able to provide large scale production and high level of investments return. Specially noted should physical and mechanical properties of nano-structured steels and alloys (strength, plasticity, toughness and so on) which will cardinally excel characteristics of respective materials developed using conventional technologies. Investigations have shown that basic principles of selection of a structure up to nano-level for low-carbon low-alloy steels can be put forward, that is: 1) morphological similarity of structural components, pre-domination of globular type structures due to reduction in carbon components and rational alloying; 2) formation of fine-dispersed carbide phase of globular morphology; 3) exclusion of lengthy interphase boundaries; 4) formation of fragmented structure with boundaries close to wide-angle ones, which inherited structure of fine-grained deformed austenite.

The Origin of Puuc Slate Ware: New Data from Sayil, Yucatan, Mexico

1995 ◽  
Vol 6 ◽  
pp. 119-134 ◽  
Author(s):  
Michael P. Smyth ◽  
Christopher D. Dore ◽  
Hector Neff ◽  
Michael D. Glascock
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Compositional Analysis ◽  
Classic Period ◽  
Scale Production ◽  
Local Production ◽  
Comprehensive Investigation ◽  
Terminal Classic ◽  
Large Scale Production ◽  
Major Producer

AbstractThis paper reports results of the first neutron-activation analysis (NAA) of ancient pottery wares and clays from the Puuc region of Yucatan. Based on ceramics from Sayil, this investigation seeks to expand exploration into the nature of commercialization during the Terminal Classic period (A.D. 800–1000). This research sought to: (a) establish the chemical composition of major Puuc wares, (b) begin to define potential raw materials and production loci at Sayil, and (c) explore the question of whether Sayil was a major producer and exporter of ceramic wares. Compositional analysis reveals that three of the four major Puuc wares (Puuc Slate, Puuc Unslipped, and Puuc Red) exhibit some degree of chemical distinctiveness, suggesting discrete production units. Compositional analysis of clays from Sayil and Loltun Cave indicates that Puuc Slate and Puuc Red Ware are compatible with clays locally available at Sayil, supporting local production of these wares, whereas Puuc Unslipped Ware initially appears to be closer compositionally to clays from Loltun. In addition, Puuc Slate is an important ware found throughout northern Yucatan that shows evidence of large-scale production at Sayil. This analysis represents the first steps of a comprehensive investigation into the Maya economy of Terminal Classic Yucatan.

scholarly journals Biosurfactants – Nature's Solution for Today's Cleaning Challenges

2021 ◽  
Vol 75 (9) ◽  
pp. 752-756
Author(s):  
Jakob J. Mueller ◽  
Hans H. Wenk
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Biological Molecules ◽  
Raw Material ◽  
Scale Production ◽  
Sustainable Solutions ◽  
Natural Substances ◽  
Head Groups ◽  
Large Scale Production ◽  
Recent Developments

Biosurfactants are surface-active molecules, developed by nature through evolution and naturally produced by different microorganisms. The most prominent examples are rhamnolipids and sophorolipids, molecules which contain hydrophilic sugar head groups and hydrophobic alkyl residues leading to an amphiphilic behavior with unique properties. Recent developments in the field of biotechnology enable the large-scale production of these biological molecules. The raw material basis is 100% renewable since sugars and oils are used as major raw materials. Additionally, biosurfactants are fully biodegradable, which allows the path back into the natural cycles. In comparison to established standard surfactants like SLES/SLS (sodium laureth (ether) sulfates) or betaines, rhamnolipids are much milder and, at the same time, show similar or even better performance in household or personal care applications. Foam behavior, solubilization and cleaning effectiveness are examples where these natural substances give excellent results compared to the synthetic benchmarks. The commercialization of biosurfactants at industrial scale now offers alternatives to consumers seeking sustainable solutions, without compromising performance. Biosurfactants combine both and set a new standard for surfactant applications.

scholarly journals Fabrication of Fiber Reinforced Plastics by Ultrasonic Welding

2018 ◽  
Vol 2 (3) ◽  
pp. 56
Author(s):  
Andreas Gomer ◽  
Wei Zou ◽  
Niels Grigat ◽  
Johannes Sackmann ◽  
Werner Schomburg
Keyword(s):  
Carbon Fiber ◽  
Large Scale ◽  
Raw Materials ◽  
Glass Fibers ◽  
Ultrasonic Welding ◽  
Scale Production ◽  
Fiber Reinforced ◽  
Cycle Times ◽  
Reinforced Plastics ◽  
Fiber Reinforced Plastics

Ultrasonic fabrication of fiber reinforced plastics made from thermoplastic polymer films and carbon or glass fibers enables cycle times of a few seconds and requires investment costs of only some 10,000 €. Besides this, the raw materials can be stored at room temperature. A fiber content of 33 vol % and a tensile strength of approximately 1.2 GPa have been achieved by ultrasonic welding of nine layers of foils from polyamide, each 100 µm in thickness, and eight layers of carbon fibers, each 100 µm in thickness, in between. Besides unidirectional carbon fiber reinforced polymer composite (CFRP) samples, multi-directional CFRP plates, 116 mm, 64 mm and 1.2 mm in length, width and thickness respectively, were fabricated by processing three layers of carbon fiber canvas, each 300 µm in thickness, and eight layers of polyamide foils, each 100 µm in thickness. Furthermore, both the discontinuous and the continuous ultrasonic fabrication processes are described and the results are presented in this paper. Large-scale production still needs to be demonstrated.

scholarly journals Evaluation of Large-Scale Production of Chitosan Microbeads Modified with Nanoparticles Based on Exergy Analysis

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1200 ◽  
Author(s):  
Samir Meramo-Hurtado ◽  
Adriana Herrera-Barros ◽  
Ángel González-Delgado
Keyword(s):  
Large Scale ◽  
Exergy Analysis ◽  
Chemical Species ◽  
Industrial Process ◽  
Simulation Software ◽  
Operating Conditions ◽  
Scale Production ◽  
Water Recovery ◽  
Novel Technologies ◽  
Large Scale Production

Novel technologies for bio-adsorbent production are being evaluated on the lab-scale in order to find the most adequate processing alternative under technical parameters. However, the poor energy efficiency of promising technologies can be a drawback for large-scale production of these bio-adsorbents. In this work, exergy analysis was used as a computer-aided tool to evaluate from the energy point of view, the behavior of three bio-adsorbent production topologies at large scale for obtaining chitosan microbeads modified with magnetic and photocatalytic nanoparticles. The routes were modeled using an industrial process simulation software, based on experimental results and information reported in literature. Mass, energy and exergy balances were performed for each alternative, physical and chemical exergies of streams and chemical species were calculated according to the thermodynamic properties of biomass components and operating conditions of stages. Exergy efficiencies, total process irreversibilities, energy consumption, and exergy destruction were calculated for all routes. Route 2 presents the highest process irreversibilities and route 3 has the highest exergy of utilities. Exergy efficiencies were similar for all simulated cases, which did not allow to choose the best alternative under energy viewpoint. Exergy sinks for each topology were detected. As values of exergy efficiency were under 3%, it was shown that there are process improvement opportunities in product drying stages and washing water recovery for the three routes.

scholarly journals High performance ceramic stones on the basis of by-products of waste heaps - screenings and coal slurry

2019 ◽  
Vol 135 ◽  
pp. 03017
Author(s):  
Khungianos Yavruyan ◽  
Vladimir Kotlyar ◽  
Evgeniy Gaishun ◽  
Anastasia Okhotnaya ◽  
Elizaveta Lotoshnikova ◽  
...  
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Raw Materials ◽  
Minimum Cost ◽  
Coal Slurry ◽  
Manufacturing Cost ◽  
Scale Production ◽  
General Description ◽  
Technological Properties ◽  
Molding Process

General description of coal dumps products processing is described: medium factional materials - screenings that do not contain carbon; kiln fractional - coal sand, coal containing up to 30%; petty factional - coal slurries, coal containing up to 50% are given. Ceramic kilns and technological properties of processing coal dumps products are given. Compositions of raw mixtures for obtaining products with a compressive strength of 10-15 MPa and density less than 800 kg / m3, and considering the fact that the molding process is carried out semi-rigid extrusion and the necessity of minimum costs for firing is defined. Depending on the technological properties of screenings, depending on the degree of grinding and firing temperature is taken into account. Flow production of modern equipment is pointed out. Technical and economic indicators showing high profitability and the prospect of large-scale production of clay tiles on the basis of coal dumps processing products due to minimal manufacturing cost are mentioned. The carried out results of the work allowed to choose the raw materials and to develop the technological scheme of production of high-performance ceramic stones with a minimum cost. Implementation of the results in practice will create a highly profitable production and make the Rostov region a major manufacturer of ceramic wall.

PRACTICAL CONTROL OF SALMONELLAE1,2

1969 ◽  
Vol 32 (4) ◽  
pp. 126-132 ◽  
Author(s):  
John C. Ayres
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Animal Husbandry ◽  
Personal Hygiene ◽  
Animal Origin ◽  
Scale Production ◽  
Mass Storage ◽  
Hygiene Practices ◽  
Equal Importance ◽  
Short Period

Salmonellae occur in practically all raw feeds and foods of animal origin; consequently the key word to their control is sanitation. The twentieth century has brought with it profound changes in animal husbandry practices, large-scale production of foods, packaging innovations, mass storage, transportation, and retailing patterns. As a consequence of these developments, substantial segments of the consuming public can be placed at risk within a short period of time. Surveillance of animals, their feeds, and other raw materials to assure that Salmonella contamination is minimized is of paramount importance. Pest control, ingredient specifications, handling requirements, improved personal hygiene practices, proper clothing, and prevention of foods to access by workmen who are ill or have cuts, sores, or boils are of equal importance to the maintenance of quality. Other requisites for holding salmonellae in check are the elimination of dust, debris, and refuse from the plant; proper cleaning of equipment and utensils in contact with foods; inactivation of microorganisms by the application of cold or heat; rigid control of ingredients; and segregation of finished products so that cross-contamination is not possible. The role of the producer, processor, warehouse man, trucker, regulatory and public health officials, doctor, retailer, and consumer in contributing to this chain of infection must be properly assessed.

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