Hybrid model for Cementos Cienfuegos S. A rotary dryer
In this paper the obtaining of the hybrid model for rotary dryer in a Cuban factory Cementos Cienfuegos S.A. is presented. The obtaining of the hybrid model in real process with any degree of complexity permitted to the validation of the proposed methodology. In the collection of experimental data are used multilevel pseudorandom signals.
Study of water confined in hydrated calcium silicate by using broadband dielectric spectroscopy
The behavior of water dynamics confi ned in hydrated calcium silicate (C-S-H) gel has been investigated using broadband dielectric spectroscopy (BDS; 10−2–106 Hz) in the lowtemperature range (110–250 K). Different water contents in C-S-H gel were explored (from 6 to 15 wt%) where water remains amorphous for all the studied temperatures. Three relaxation processes were found by BDS (labeled 1 to 3 from the fastest to the slowest), two of them reported here for the first time. Both the temperature dependence of the relaxation time and the relaxation strength of these processes depend on water content. Characteristics of these processes will be discussed in this work.
Tyre and alternative fuels universal transport at Cruz Azul plant in Hidalgo (Mexico)
This article describes the innovative installation developed by STHIM Maquinaria, S.A. at Cruz Azul plant in Hidalgo (Mexico). The difficulty to design this complete automatic installation lies on the diff erent types of materials operated by the two lines, from tyres to plastics or textile materials. Besides from this the limited space available was also a difficult point to add at the engineering stage. The result is described in the following lines.
Natural radioactivity of building materials. Concrete application. Part II. Indoor radiation: radon gas
This article discusses issues related to the different types of natural radioactivity inside the buildings, their sources and influences. More specifi cally, it studies environmental radioactivity due to the presence of radon gas within built spaces, as well as its origin sources and recommended levels. This paper is the second part of a work about natural radioactivity of building materials, published by the same authors, in the same journal.
Also, we make a review of the existing regulatory framework, both international and national, related to radon and its short half-life descendants. This work is part of the doctoral thesis of the first author, Beatriz Piedecausa Garcia, to whom the other authors appreciate the efforts to prepare the text now published and the authorization and the facilities provided to access to her work.
Best Available Techniques for Cement Manufacturing
Directive 96/61 on Integrated Pollution Prevention and Control, defined the concept of Best Available Techniques and established the Information exchange processes that determine these techniques.
This article describes the outcome of this information exchange, called BAT Reference Document in the Cement, Lime and Magnesium oxide manufacturing industries. This BREF document, concluded in 2010 its second revision. The results on elaboration frame, BAT concept, are presented here, together with their associated emission levels.
Three Spanish projects have been awarded in the Holcim Awards 2011 for Sustainable Construction
The Holcim Foundation for Sustainable Construction announced at a ceremony in Milan on 15th September the winners of the 3rd International Holcim Awards competition for sustainable construction projects and visions from across Europe. A total of USD 300,000 was presented to ten outstanding projects under
The Swiss-based Holcim Foundation for Sustainable Construction conducts the competition in five regions in parallel across the world. More than 6,000 submissions projects entered and 2,251 were accepted for the jury evaluation. 572 of these accepted projects were European and 70 were from Spanish teams what represents the more numerous national participation of European countries after Italy.
Bridge on the Turia river between Manises and Paterna (Valencia). First international experience on the use of recycled concrete in a cable-stayed bridge (Part II)
The highway CV-371, which connects the towns of Manises and Paterna, in the metropolitan area of Valencia (Spain), crossed the Turia river with an old bridge, 145 m long, with 9 short spans.
To provide a safety circulation to both pedestrians and bikers it was necessary to widen the bridge. In addition, its morphology did not allow the pass of the foreseen maximum flow of the Turia river.
Therefore a new bridge was designed, with two spans of 55 and 90 m respectively, in the same place of the existing one. This implied its demolition. For that reason, it was proposed to recycle its concrete to be used as aggregate in the new bridge.
The main features of both the existing and the new bridge are described in the article, as well as the propreties of the concretes of the former, the specifi cations of the recycled concrete, the demolition process of the existing bridge, the processing of the concrete to obtain the recycled aggregate, the characterization of the constituents of the recycled concrete, its mix design and the the construction process of the new bridge.