Ton Of Cement Research Articles

Foamcrete construction blocks using industrial wastes- A sustainable approach

There is a wide growth in construction industry in recent years, which is a very important area of concern for all the stakeholders. There is a wide-ranging diminution of natural resources, especially river sand. Also, the current statistics shows that for the production of one ton of cement, there is a discharge of one ton of carbon dioxide, which creates lot of environmental pollution. This has directed the investigators to find a more sustainable solution. Hence this study is oriented towards the development of a new building material in foamed concrete, in which natural river sand is completely substituted with manufactured sand, which is being substituted partially with quarry fine dust, which is an industrial by-product. The production of alternate building blocks using fly ash, GGBS and quarry dust can be very effectively used for the overwhelming construction processes. The consumption of industrial by-products in foamcrete, compensates the deficiency of natural resources, which solves the disposal of the above waste materials and safeguards the nature. With the use of this foamcrete blocks (density less than 1800 kg/m3) as infills, slender sections can be designed for the framed construction works. Correspondingly, the thermal insulation properties of foamcrete blocks make it more acceptable in the present construction scenario. This is an attempt to focus the attention to discuss the utilization of industrial wastes in construction blocks. It has been observed that the construction blocks, made with these industrial wastes, have similar strength and other characteristics as that of conventional bricks. The maximum attained compressive strength is 13.29 N/mm2.

COMPARISON OF LIFE CYCLE ASSESSMENT TOOLS IN CEMENT PRODUCTION

The cement industry is known to be the largest consumer of energy and natural resources. Globally, an average of a ton of cement is needed by every individual each year. Cement, being the major constituent of concrete, is the most manufactured and most consumed product, and its environmental impact continuously increases; this in turn causes climate change and global warming. This has stimulated the quest to understand the environmental implications of the cement industry through life cycle assessment. The need to review life cycle assessment (LCA) software that is available for cement production is thus germane, as the desired output to be obtained in an LCA largely depends on the choice of the software package to be used. Of the 45 LCA software tools reviewed, we report on a comparison of four suitable and prominent software packages — GaBi, OpenLCA, SimaPro, and Umberto — for the cement industry. From our analysis, SimaPro emerged as the best software tool for the cement industry, based on the required standards. However, every user knows what is required in a tool; thus this paper helps to link the desired output to a particular software tool.

Feasibility of sustainable construction materials for concrete paving blocks: A review on waste foundry sand and other materials

This study examines the feasibility of using various waste materials in concrete paver blocks to reduce consumption of natural resources, increased global warming and hazardous waste material generation. Exessive waste is generated from the construction, thermal power plant and industrial sector causing landfill issues too. Sand is the most demanding resource in the construction industry, there is a scarcity of natural aggregates due to rapid urbanization, an estimated 1.4 billion tons of sand will be required by 2020, compared to 630 million tons in 2010. Approximately 1 ton of cement produces 1 ton of CO2. Nowadays cement production is reached to 337.32 million tons in 2018–19 contributing 7–8% CO2 emission globally. These statistics show the graveness of increasing global warming, resource demand and environmental deprivation. Therefore, researchers are finding out alternatives to the construction materials considering the need and future scope of development through sustainability. The following materials are studied in this paper: Waste foundry sand, fly ash, GGBS as a replacement to cement and aggregates in concrete paver blocks. Various test results are mentioned like compressive strength, water absorption, splitting tensile strength, flexural strength and abrasion resistance test along with the optimum replacement percentage values of various waste materials which can be used to get better results. Studies showed cement can replace with 100% by fly ash in geopolymer concrete. GGBS can use upto 50–70%, Waste foundry sand upto 30–50%, 25% fly ash and 75% GGBS for better strength results also utilization of 45% waste foundry sand an 34% fly ash gives better compressive strength results. Reutilization of these materials will tend towards sustainable development through economic and green pavers.

Recent progress in environmentally friendly geopolymers: A review

The manufacturing of cement demand burning of huge quantities of fuel as well as significant emissions of CO2 resulting from the decomposition of limestone that consequently resulted in severe environmental impact that is estimated by one ton of CO2 per ton of cement. Geopolymerization technology is an effective method for converting wastes (containing alumina and silica) into useful products. It can reduce CO2 emissions significantly from the cement industry. The geopolymerization process usually starts with source materials based on alumina/silicate in addition to alkaline liquids. The compressive strength, setting time, and workability of the final product depends mainly on the type and proportions of the precursors, the type and strength of the activator, the mixing and curing conditions. The structural performance of a geopolymer is similar to that of ordinary Portland cement (OPC). Therefore, geopolymer can replace OPC, and thus decreasing the energy consumption, reducing the cost of the building materials, and minimizing the environmental impacts of the cement industry. This review summaries the mechanism of geopolymerization, including the controlling parameters and different raw materials (fly ash, kaolinite and metakaolin, slag, red mud, silica waste, heavy metals waste, and others) with particular focus on recent studies and challenges in this area.

Space-Borne Monitoring of NOx Emissions from Cement Kilns in South Korea

Nitrogen oxide (NOx) emissions from the South Korean cement industry are investigated with remote-sensing measurements, surface observations, and in situ aircraft measurements. In the Yeongwol, Danyang, and Jecheon regions of central South Korea, six closely located cement factories produce 31 million tons of cement annually. Their impact on the regional environment has been a public-policy issue, but their pollutants have not been continuously monitored nor have emissions inventories been fully verified. Using a newly developed downscaling technique, remote-sensing analyses show that Ozone Monitoring Instrument (OMI) NO2 column densities over the cement kilns have more than twice the modeled concentrations, indicating that the kilns are one of the most dominant NOx emission point sources in South Korea. Observed NOx emissions are stronger in the spring, suggesting that these sources play an important role in the formation of surface ozone and secondary particulate matter. These emissions also slightly increased in recent years, even while most major South Korean cities posted a declining trend in NOx emissions. Photochemical models (during May to July 2015) demonstrate that emissions from the South Korean cement industry have significant environmental impacts, both on surface ozone (up to approximately 4 ppb) and PM2.5 (up to approximately 2 µg/m3).

Cement Formation with Marble Powder as Substitute

Lately marble is viewed as most significant beautifying construction materials. MP is which severalty impact on nature and medical issues. Marble powder materials are a fine powder. It is developed from chopping, molding and washing process. The creation of cement is expanding about 3% yearly. The creation of 1 ton of cement frees around 1 ton of CO2 to the air. This explorationmeans to intend the impression of using MP as in part substitution of cement. Cement which is one of constituents utilized in the creation of concrete has gotten costly and scant because of which development cost increments. In present investigation cement has been partially replaced with marble powder in five different percentage mixes of 0%, 5%, 10%, 15% and 20% weightiness of cement content in concrete. The key factor taken into concern is proportion of MP concrete is tested for workability, compressive strength, flexural strength and tensile strength.

An experimental studies on strength properties of bacterial concrete

Cement concrete is a massively “used construction material throughout the world and in the process of manufacturing of one ton of cement 850 kg of CO2 is emitted into the atmosphere, In this research, bacterial concrete was produced by replacing part of cement in controlled concrete with equal volume of class F fly ash enriched with bacteria Bacillus sphaericus (B. sphaericus) such that the strength of 28 days of bacterial concrete is at par with controlled concrete. B. sphaericus precipitate Calcium Carbonate while producing bacterial culture which fills the minute pores in bacterial concrete and makes it to attain higher strength. Experiments were made by replacing cement from 0% to 50% with class F fly ash enriched with bacteria B. sphaericus and found that”bacterial concrete made with of 25% replacement (M2CFB25) is suitable in fresh state and in hardened state. In fresh concrete with water cement ratio of 0.4 the compaction factor of controlled concrete (M2CC) was 0.85, fly ash concrete with 25% replacement to cement (M2CF25) was 0.84 whereas for M2CFB25 it was 0.89 which is more advantageous for M2CFB25to get good compaction. Compressive strength of 28 days concrete M2CC, M2CF25 and M2CFB25 are 45.19 N/mm2, 41.23 N/mm2 and 48.11 N/mm2. Similarly 28 days concrete split tensile and flexural strength of M2CFB25 is higher than M2CC and M2CF25. Fly ash concrete M2CF25 has gained less compressive strength, split tensile and flexural strength than M2CC on 28 days of curing. X-Ray diffraction test results indicated M2CFB25 have more peaks than M2CC and M2CF25 and there by confirmed the presence of higher CaCO3 in bacterial concrete. The usage of bacterial concrete M2CFB25 in lieu of M2CC will reduce the amount of CO2 emitted to the atmosphere and reduce the depletion of natural resources.

A Systematic Approach to Calculate Unit Emergy Values of Cement Manufacturing in China Using Consumption Quota of Dry and Wet Raw Materials

The Chinese cement industry produced 2150 million metric tons of cement in 2014, accounting for 58.1% of the world’s total. This industry has a hugely destructive effect on the environment owing to its pollution. The environmental impact of cement manufacturing is a major concern for China. Although researchers have attempted to estimate impacts using life cycle assessment approaches, it lacks the ability to provide a holistic evaluation of the impacts on the environment. Emergy analysis, through ecological accounting, offers environmental decision making using elaborate book keeping. In spite of the high environmental impact of the cement industry, there has only been a handful of research work done to compute the unit emergy values (UEVs) of cement manufacturing in China. A thorough study of existing UEVs of cement manufacturing in China showed pitfalls that may lead to inaccurate estimations if used in emergy analysis. There is a strong need for a new, updated UEV for cement manufacturing in China, particularly reflecting both the dry and wet raw materials in the manufacturing process. This paper develops a methodology to calculate the nonrenewable resources used in cement manufacturing, particularly using mainstream cement production line. Our systematic approach-based UEV estimates of cement manufacturing in China using the quota method are 2.56 × 1012 sej/kg (wet material) and 2.46 × 1012 sej/kg (dry material). Emergy indicators such as environmental loading ratios which were calculated at 2390 (wet material) and 2300 (dry material); emergy yield ratios at 15.7 and 15.8; and emergy sustainability indices at 0.0066 and 0.0069 for dry and wet materials used in cement manufacturing, respectively; these show the immense impact on the environment in China.

Domınance of materıal composıtıon on mechanıcal propertıes of normal and hıgh strength grade bınary blended geopolymer concrete

The utilisation of pozzolanic materials as the replacement to conventional cement material have the potentiality to mitigate the pollution caused by the émission of carbon based green house gases which are a main source for global warming problem. For every production of 1 ton of cement it was approximated that the emission of carbon based green house gases are about 1 ton. Keeping this in view, a new material called Geopolymer which was first coined by Davidovits has gained a lot of interest by the researchers. In this study, different molarity variations of NaOH in the order of 4M, 6M, 8M, 10M, 12M and 14M and also the blending of mineral admixtures like Fly Ash and Ground Granulated Blast Furnace Slag with percentages (50%+50%) and the mechanical properties of normal M30 and high strength grade M70 binary blended Geopolymer concrete were studied after 28 days of ambient curing and were reported. The test results revealed that the effect of molar concentration of NaOH at 12 M is effective and the optimum replacement of mineral composition of source materials is (50%+50%) fly ash and ground granulated blast furnace slag.
 
 

Alternative supplementary cementitious materials for sustainable concrete structures: a review on characterization and properties

Currently, one of the main priorities for a government is to realize sustainable development. Strategies are required to protect the global environment, enhance employee health and safety, reduce emissions, and use fuels and raw materials responsibly across all sectors of the economy. Blended Portland cements containing supplementary cementitious materials (SCMs), usually industrial by-products, are excellent examples of industrial ecology. In particular, they offer a solution for reducing environmental impacts from several industries. In fact, with every ton of cement produced, nearly a ton of CO2 is emitted. The use of SCMs as a cement substitution reduces these CO2 emissions, saves non-renewable material sources, minimizes waste, and enhances the properties of the concrete. High-quality SCMs are becoming increasingly restricted. With the growing demands for cement, new sources of SCMs, often called alternative SCMs (ASCMs), will need to be used. However, this brings another challenge, as ASCMs are often comprised of local materials, with smaller volumes and more variable compositions. Accordingly, efficient and rapid methods are necessary for evaluating their performance and reactivity in concrete materials. Moreover, there is a need to characterize the chemical, physical, and mineralogical properties of the ASCMs. This paper presents the requirements for materials to qualify as SCMs, an example of a rapid screening test for assessing the performance of ASCMs, and an inventory of materials with favorable properties.

Treatment of end-of-life concrete in an innovative heating-air classification system for circular cement-based products

A stronger commitment towards Green Building and circular economy, in response to environmental concerns and economic trends, is evident in modern industrial cement and concrete production processes. The critical demand for an overall reduction in the environmental impact of the construction sector can be met through the consumption of high-grade supplementary raw materials. Advanced solutions are under development in current research activities that will be capable of up-cycling larger quantities of valuable raw materials from the fine fractions of End-of-Life (EoL) concrete waste. New technology, in particular the Heating-Air classification System (HAS), simultaneously applies a combination of heating and separation processes within a fluidized bed-like chamber under controlled temperatures (±600 °C) and treatment times (25–40 s). In that process, moisture and contaminants are removed from the EoL fine concrete aggregates (0–4 mm), yielding improved fine fractions, and ultrafine recycled concrete particles (<0.125 mm), consisting mainly of hydrated cement, thereby adding value to finer EoL concrete fractions. In this study, two types of ultrafine recycled concrete (either siliceous or limestone EoL concrete waste) are treated in a pilot HAS technology for their conversion into Supplementary Cementitious Material (SCM). The physico-chemical effect of the ultrafine recycled concrete particles and their potential use as SCM in new cement-based products is assessed by employing substitutions of up to 10% of the conventional binder. The environmental viability of their use as SCM is then evaluated in a Life Cycle Assessment (LCA). The results demonstrated accelerated hydration kinetics of the mortars that incorporated these SCMs at early ages and higher mechanical strengths at all curing ages. Optimal substitutions were established at 5%. The results suggested that the overall environmental impact could be reduced by up to 5% when employing the ultrafine recycled concrete particles as SCM in circular cement-based products, reducing greenhouse gas emissions by as much as 41 kg CO2 eq./ton of cement (i.e. 80 million tons CO2 eq./year). Finally, the environmental impacts were reduced even further by running the HAS on biofuel rather than fossil fuel.

Elaboration of eco-efficient vegetable fibers reinforced cement-based composites using glass powder residue

This study evaluates the potential use of glass powder residue as partial replacement of cement in the fibers cement industry. Fibers cement composites were elaborated according to slurry dewatering method. Three formulations were studied; two cementitious matrices with a partial replacement of cement by glass powder residue (20 and 50% by weight) and a cementitious matrix with a partial replacement of cement by 20% by weight of limestone (commonly used as mineral addition in the fibers cement industry). The effect of these mineral additions on the cement hydration was evaluated using isothermal calorimetry. Physico-mechanical properties of the composites were determined at 8 days and after durability tests. Moreover, the potential application of the glass powder residue into the fibers cement industry was evaluated by determine the energy demand of the production of cement and the energy performance of fibers cement composites elaborated from the glass powder residue.The results showed that cement pastes containing the glass powder residue present a higher heat of hydration in comparison to the control. The partial replacement of cement by 50% by weight of glass powder residue increases the flexural strength of composites at 8 days and after durability tests. The results also showed that the production of 1 ton of cement partially replaced by glass powder residue requires lower energy than the cement partially replaced by limestone. Finally, according to the study, the use of the glass powder residue in production of fibers cement composites can provide important technical, environmental and economic benefits.

The influence of various basalt mineral and sodium hydroxide concentration on the physical properties and characterization of geo-polymer products

Environment friendly product has a major concern nowadays. The use of cement as a binder to make concrete cannot be negligible since cement production has contributed to the increasing of CO2 emissions. To produce 1 ton of cement, approximately 1 ton of CO2 is also released from the process. Rock geo-polymer cement as one categories of cement is known to be more environmentally friendly than Portland cement. Basalt rock has an opportunity for a material substitute in geo-polymer cement production. Variability influence of basalt and sodium hydroxide concentration on the physical properties and characterization of Geopolymer products are observed in this research. The raw materials used are basalt, sodium hydroxide, sodium silicate, and water. Geo-polymer is made by adding basalt as much as 2.5 %, 5 % and 7.5 % with basalt grain size of 80, 150 and 270 mesh. This research shows that the greater variation of sodium hydroxide concentration, the smaller compressive strength produced; however the absorption considered becomes greater. Geo-polymer with addition sodium hydroxide 2.5 % with basalt grain size of 270 mesh has a highest compressive strength and the lowest absorption rate. Characterization of the sample using XRF and XRD have indicated that the sample has the highest SiO2 compound content of 48.731 % with 2.5 % sodium hydroxide in the 270 mesh, while the phases formed were Albite Na(Si3Al)O8, Cristobalite (SiO2), Forseterit (Mg2SiO4), Anorthite Ca(Al2Si2O8) and Magnetide (Fe3O4).

Application of Seawater and Sea Sand to Develop Geopolymer Composites

Worldwide, concrete is predominantly used as a versatile building material with its highest consumption on the earth. Nevertheless, its exigency accelerates day by day exhausting restricted natural resources in its manufacturing. Consequently, in order to prevent the degradation of these natural confined aggregates resources, it’s highly essential to employ other alternative profuse materials in their place. On the one hand, the sea Sand is existing in huge quantity below seas and oceans while on the other hand, restricted river Sand resources are being quarried haphazardly and hence reaching to their end. What’s more, to flashlights on, the production of every ton of cement contributes to the emission of an almost equal quantity of CO2 with high energy consumption. Also, it is worth mentioning that freshwater resources are in the limited quantity and, therefore, mankind is not getting sufficient fresh water even to drink in some corners of the world. In present experimental investigations, all the above burning dilemmas are kept in mind and hence, the sea Sand is used as an alternative to river Sand whereas sea water is used instead of distilled water for laboratory investigations on the properties of Geopolymer concrete and mortar in the total absence of Ordinary Portland Cement. The results demonstrated that the sea sand and seawater have no doubt affected the strength of Geopolymer concrete and mortar but just insignificantly.

Mechanical Behavior of Double Skinned Composite Hollow Columns using Geopolymer Concrete

This paper comprises of the experimental study of double skinned (DSCFT) Composite hollow columns using Geopolymer concrete. The diameter-thickness (D/t) ratio and the hollowness ratio were consideredas main parameters in designing the specimens. The Geopolymer Concrete used in this project is the most promising technique. It is composed of fly-ash, fine aggregate, coarse aggregate and alkaline solution. By using large volume of ordinary Portland cement (OPC) concrete, the production of cement increases 3% annually. The production of one ton of cement directly liberates about 1 ton of CO2 and indirectly liberates 0.4 ton of CO2 to atmosphere. Among the greenhouse gases, CO2 contributes about 67% of global warming. In this respect fly ash based geopolymer mortar is highly considerable. But most of the previous works on fly ash-based geopolymers concrete reveals that hardening is due to heat curing, which is considered as a limitation for cast in situ applications at low ambient temperatures. In order to overcome this situation, replacing the Ground blast furnace slag with fly ash for various proportions to achieve geopolymer concrete suitable for curing without elevated heat. The Scope of this project is to find optimization level of Ground Granulated blast furnace slag in geopolymer concrete for curing in ambient condition and to analyze the compressive Strength of optimized GGBS based Geopolymer Concrete filled double skinned steel tube by varying the size of the steel tubes.

Compressive Strength Evaluation of Ordinary Portland Cement Mortar Blended with Hydrogen Nano-Bubble Water and Graphene.

Abnormal climate changes have occurred all over the world due to greenhouse gases (GHGs). Various countries are targeting emission reductions of GHGs in 2020 and trying to GHGs those in multiple fields. Cement-based structures account for a large part in the construction industry. One ton of carbon dioxide is produced during the manufacturing process for a ton of cement. Therefore, decreasing cement usage is essential for carbon dioxide reduction. However, strength characteristics of cement are necessary conditions to meet the required strength of a structure. Therefore, it is necessary to develop cement substitutes and economic additives. In this study, we proposed an eco-friendly blend ratio by comparing the compressive strength of Ordinary Portland Cement (OPC) mortar and two variations. One was a mortar with a small amount of APTMS-sGO added. The other was a mortar mixed with HNBW (hydrogen nano-bubble water) as an enhanced material instead of ordinary water. The mortar added with 0.1% of APTMS-sGO showed improved early strength compared with OPC mortar. Its strength was enhanced 31.1% by using HNBW as functional water. Strength was improved 20.4% for cement mortar added with Graphene Oxide after reacting with SAM containing APTMS. When the texture of both mortars became denser, early compressive strength at 7 days each was 20.4-31.1% higher than that of OPC mortar. Finally, the strength was increased by 10.2% at 28 days.

Durability of Concrete Structures with Sugar Cane Bagasse Ash

The environmental impact of cement production increased significantly in the previous years. For each ton of cement produced, approximately a ton of carbon dioxide is emitted in decarbonation (50%), clinker furnace combustion (40%), raw materials transport (5%), and electricity (5%). Green strategies have been advanced to reduce it, adding natural or waste materials to substitute components or reinforce the mortar, like fibers or ashes. Sugar cane bagasse ash is a by‐product generated from sugar boilers and alcohol factories with capacity to be used in concrete production. Composed mainly of silica, it can be used as mortar and concrete mineral admixture, providing great economic and environmental advantages, particularly in regions with sugar culture and industrial transformation like Brazil. In this research, a study of partial substitution of Portland cement by sugar cane bagasse (SCB) is analyzed, in order to reduce clinker in concrete volume, responsible for high emission of CO2 to the atmosphere. An experimental campaign with cementitious pastes was carried out to evaluate the durability properties’ changes due to SCB ash use. Samples containing 15% of sugarcane bagasse ash unveiled good results in terms of durability, indicating that concrete structure with sugar cane ash research is a new and important scientific topic to be highlighted.

Geopolymer Masonry Block: A Substitute Material for Cement Concrete Block

In today’s era, it is known that equal amount of CO2 is been produced per ton of cement while its production which is very resource and energy intensive process. And this issue leads to develop a new alternative material such as fly ash, ground granulated blast furnace slabs i.e. CGBS because cement industries are creating trouble environmental issues. Also for sustainability, there is essential requirement to build masonry units using this alternative materials. Fly ash which is biproduct of thermal power plant is utilized by Geopolymer technology. In the current paper, cement and geopolymer blocks are produces by identical method. Properties of geopolymer masonry block such as compressive strength, modulus of elasticity, density, initial rate of absorption and water absorption are defined and compared. The results states that geopolymer blocks can be proposed for use of masonry units for structural masonry. And so use of conventional cement can be reduced.

Review on Partial Replacement of Cement in Concrete by Using Waste Materials

Concrete ingredients is different material like binding material (cement+ fly ash), fine aggregate, coarse aggregate and water. Today construction cost is very high with using conventional materials due to unavailability of natural materials. This problem can be solved by total replacement of concrete with different material which is not convenient in terms of required properties. Due to this limitation of unavailability of material which plays the vital role of concrete we have only choice of partial replacement of concrete ingredients by waste materials. Overv4.2 billion tons of cement was consumed globally in 2018 based on survey of world coal association and also cement production emits CO2 in to the atmosphere which is harmful to the nature. If we can partially replace the cement with the material with desirable properties then we can save natural material and reduce emission of CO2 in to the atmosphere. This industrial waste dumping to the nearest site which spoils the land and atmosphere as well as it also affects aesthetics of urban environment so use of this waste material in concrete is cost effective as well as environment friendly way to disposal of waste. The primary objective of this study is to select the waste material which gives desirable properties with concrete. This study includes previous investigation done on the mechanical and chemical properties of concrete produced using partial replacement of cement by waste materials.

The Study of Concrete Durability with PPC Premium and PPC Non Premium Cement

Concrete structures reinforced with steel formed an important part of recent infrastructures. Today, the rate of use of cement is higher than 40 years ago. An approximation amount of 11 billion metric ton of cement per year has been consumed in the whole world. The aims of this research are: (1) to obtain the durability value of concrete with PPC Premium Cement and PPC Non-Premium Cement, (2) to obtain the degree of comparison of concrete durability, (3) to obtain the durability parameters. This research based on ASTM International standards, conducts in 224 days non-stop, to obtain following data: (1) compressive strength, (2) rebound number, (3) pulse velocity number, (4) modulus of rupture, and (5) corrosion rate. The test result: (1) PPC Premium cement give a relatively good performance rather than PPC Non-Premium cement. This is based on both destructive and non-destructive test, (2) the modulus of rupture’s value also giving the PPC Premium cement act relatively good than PPC Non-Premium cement, (3) test on severe environment, concrete treatment by mean of waterproofing proved to be effective to reduce the rate of steel destruction., (4) on a practical use, cement with high fineness modulus can give a better performance.