Behavior and hidration of a portland cement made from ceramic waste as alternative raw materials
A clinker and cement obtained from a raw mix containing ceramic tile waste as alternative raw materials have been characterized. The hydration process, its physical and chemical behavior have been studied. The results have demonstrated that both clinker and cement meet all requirements and request demanded by European standards, although the cement obtained from ceramic waste present content of ZnO, ZrO2, B2O3 above a cement reference to a cement factory.
The results obtained have showed that the hydration of the new cement is delayed, which is manifested by lengthening of the setting times and a lower mechanical resistance 2 days. However, the microstructural study carried out by BSE/EDS has revealed that the morphology and composition of C-S-H gel formed is comparable to that of a Portland cement paste.
Future trends in the manufacture of commercial cements: new pozzolanic additions
The cost of energy, extraction costs, purchase of raw materials, environmental pressures and reduced availability of certain pozzolan, are forcing the cement companies to focus on two priorities: In search of alternative fuels and recycling of new wastes like a way to be competitive and environmentally sustainable.
Within the second priority line, this work reflects the experiences gained by the Group of Recycled Materials from Eduardo Torroja Institute (CSIC). 4 wastes generated in different industrial sectors: paper, ceramic, steel and oil were investigated. The results confirmed the scientific and technical feasibility of these residues
as active additions to Portland cement. The results are serving as pre-standard studies, such as SiMn slag presented to the Subcommittee 3 AEN/CTN-80 and also to WG 6 CEN / TC 51.
EQUIPMENT PROVIDERS 1
Material extraction from silos: strains on extraction systems due to silo wall inclination
This document shows the calculation methodology to know the strain exerted anywhere of a silo depending of the geometry and the existing load, as well as the experimental testing of the data obtained. Given some initial parameters, dimensions and geometry silo, density, repose angle and general characteristics, the equations deducted from the strain analysis proposed by Jansen & Koenen, was validated experimentally at Vidmar workshops.
To validate this theory, Vidmar was made silo according the follow characteristics:
- Geometry: Rectangular.
- Height: 2.000 mm.
- Lenght: 1.200 mm.
- Width: 645 mm.
A set of load cells was installed in different point in order to read the strains applied for this study. A total of 18 tests has been done with materials such as gravel, lime and sand.
EQUIPMENT PROVIDERS 2
On Line laboratory for analysis of Cement. The FKV solution
Nowadays, during the production of the cement, samples to be analyzed are manually taken by the operador with a predefined interval, typically more frequently during the startup of the mill. Each sample is partially used for immediate analysis, typically blain or residue, sulphates and carbonates, while the rest of the sample is collected as composite sample for laboratory analysis or physical testing.
The results obtained from the immediate analysis are manually registered and/or entered into a process computer (e.g.DCS) to maintain or correct the parameters of the mill and dosing systems.
How to adapt to the new EHE-08
The use of new generation superplasticizers, those designed specifically for Ready Mix Concrete, helps in the design and production of high quality and low dispersion fluid concretes, thus complying easily with the new regulation. With the use of these new superplasticizers the Ready Mix producer ensures a high quality
product at a very competitive cost: fluid concretes have lower dispersion of results, are placed faster, have uniform surface finishes and retain their workability longer. All this, without increasing cement content, which has the most important impact on costs.
Mapei has a wide range of new generation superplasticizers, designed and well adpated for all concrete types. There are products designed to work with siliceous or limestone aggregates, in summer and winter conditions, and with all kinds of cements. Together with a high technical expertise and in situ advisement, Mapei is the best partner for any Ready Mix producer that wants to remain competitive while complying with the new regulation EHE-08.
Implementation of an Energy Management System on a cement plant
In a pioneer manner, the Group Cementos Portland Valderrivas decides to implant in its cement factory El Alto an Energy Management System according to the Project of Spanish Norm 216301.
This system is implanted for the very first time in March 2007, supported by the Environmental System already implanted in the factory. The aims are based on an exhaustive control and management of the energy consumptions. At the end of the very same year AENOR performs an initial audit to obtain a certification of the Energy Management System.
The group of UNE norms approved by AENOR during the month of November 2007 including the UNE 216301:2007 norm is published in the BOE in the resolution of the 10th of December from the Industrial Development General Management. At the same time the definitive certifi cation of the Energy Management System is obtained.
The implantation of the system has resulted on a great deal of undeniable benefits, but also in the assimilation process some difficulties have arisen, for example a great number of measurement points to manage or the difficulty to assign values for indicators.
The system contributes with the know-how on consumptions not considered until now and it manages a new perspective of other consumptions already handled.
In global manner the decision of the implantation of the system shows the awareness of the high direction of the company and the responsibility assumed by it as a great consumer of energy.
Control of persistent pollutant emission in cement industry using waste as fuel
At present dioxin stack emission determinations are set according the European Standard EN1948 applying until the last update short-time samplings of 8 hours. Nevertheless, automatic sampling systems exist now that are capable to be permanently sampling in the stack. These systems allows the integration of a longer period, obtaining by this most representative results, a better approach to study the relation between operation conditions and emission levels. European Committee for Standardisation has been commissioned to prepare a “part 5: long-term sampling determination of PCDD/Fs and DL-PCBs” for EN1948
that should be ready in 2010.
In this study are presented the first results obtained by the use of continuous sampling systems in clinker kilns. The systems were installed in one clinker kiln using conventional fuel and another one where waste co-incineration is carried out. The results, obtained in a basis between 7 and 56 sampling days, confirms that levels of dioxin emissions are in both kilns consistently below the standard limit of 0,1 ng I-TEQ/Nm3 set in the Spanish legislation RD 653/2003.
Installation for transforming plastic waste into cement kiln fuel in Cemex España, S.A. Castillejo cement plant. Toledo
On May 2009 Cemex España, S.A. commissioned an installation for transforming plastic waste into a product valorizable in its cement rotary kilns. The plant production capacity is over 15 tons/h, about 35.000 tons/y. It´s been estimated that a petroleum coke substitution rate between 25 and 30% will be attained in the medium term.
Lafarge Sustainability Ambitions 2012-Lafarge global: commitments and achievements
Lafarge Group has strategic positions in construction materials sector, and it is around the world. Aware of economic, social and environmental importance of our activity, Lafarge is committed to run our business in a sustainable way. This commitment is showed in “Sustainability Ambitions 2012”, and they have been produced from listening to communities.
Lafarge chooses to concentrate on areas where there are the main environmental and social challenges. These goals involve all company, and include non-governmental organization WWF) and stakeholders.
“Sustainability Ambitions 2012” are focusing on three areas: management, social and environmental. In management of our business we want to improve our employer’s safety, being good relations with our neighbours, a fair competition and searching satisfi ed customers with our products and innovation.
Employee skills, health with regular medial examinations and HIV/AIDS and malaria programmes covering prevention, testing and antiretroviral therapies for workers and their families, are included in social responsibilities. Lafarge knows that it activity can produce an environmental impact, for all we have choose most demanding targets. The environmental goals are supported in our WWF agreement like “Conservation Partner”. The targets involve from quarry rehabilitations, encouraging biodiversity, regular environmental audits, to reducing CO2 and pollutants emissions (NOx, SOx and dust).
The importance of these goals is that they are implemented worldwide in all our plants, in countries with specific legislation or without it. In addition, our goals go beyond current regulations.
Construction process of the highest building of Andalusia: Towers of Hercules
Promoted by Valcruz Gestión, Sando Construcciones was the company in charge of rising these two spectacular and original cylindric towers, the highest in Andalusia, which houses several offices. This structure shows the technical capacity, the quality and the experience that Sando has developed over the last thirty five years regarding singular buildings. The project was done by the architect Mr. Rafael de la Hoz Castanys who also was in charge of project management together with the technical architect Mr. Rafael Vegas Sánchez.
Apart from the two towers, which are joint by a pedestrian bridge so that they can be considered as a unique building, construction works also included an open parking area and the urbanization.