Titanium is a very important element for several industrial applications, being one of the ninth most abundant elements in the Earth's crust (0.63% wt). In this work it will discuss the different mining and industrial activities involved in the production of titanium dioxide. The first step analyzed will treat about the beneficiation mining process of titanium mineral, and secondly, it will discuss the two main processes of the TiO2 manufacturing (sulphate and chloride routes). In addition, we will show different uses of the titanium dioxide pigment as filler in paper, plastics and rubber industries and as flux in glass manufacture, etc. Finally, we will show that the old wastes are currently called co-products since they were valorized, being commercialized by the Spanish industry of TiO2 production in different fields such as agriculture, civil engineering, or cement manufacturing.

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18The industry of phosphoric acid produces a calcium-rich by-product known as

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Background: The effects of noise are particularly harmful for the newborns, and therefore this study assesses and characterizes noise levels in a neonatal intensive care unit (NICU) in a medium-size hospital in the city of Huelva with the aim of optimizing the management and quality of care for newborns. Methods: The equivalent continuous sound level was recorded as A-weighting curves using Type I sound level meters with levels measured during 100 milliseconds along to 15-day period in the both critical (in and out of incubators), and intermediate care units from a medium-size hospital. These devices were attached to a central beam 80 cm below the ceiling and into one of the incubators. Results: The maximum noise levels measured for critical (C-in), C(out) and intermediate (I) were: 88.8 dBA, 97.2 dBA and 92.4 dBA, respectively, while for the equivalent noise levels for the total measuring period (15 d) were 57.0 dBA, 63.7 dBA, and 59.7 dBA, respectively. The Fourier frequency analysis has demonstrated several typical periods related to both work activities and family visit, which were: 7 days, 24 h, 12 h, and 3 h. Conclusions: The statistical analysis revealed a clear correlation between the noise level, the kind of care room, and the time of the day. The results show that the values recommended by international bodies and agencies (AAP, WHO) are surpassed by a large margin, thus making it crucial that certain norms are followed in order to reduce the noise level in the NICU, by means of physical alterations to the layout, and raising awareness of health care personnel and visitors in order to encourage noise prevention in the daily care work and conversation. And finally, has been demonstrated that by applying the t-Student test the mean noise values in both wards are significantly different, which leads us to state that the noise level for the critical wards are higher than in the intermediate care ward.

This paper reports the preparation of sulphur polymer cements (SPCs) incorporating waste ilmenite mud for use in concrete construction works. The ilmenite mud raw material and the mud-containing SPCs (IMC-SPCs) were characterised physico-chemically and radiologically. The optimal IMC-SPC mixture had a sulphur/mud ratio (w/w) of 1.05 (mud dose 20 wt%); this cement showed the greatest compressive strength (64 MPa) and the lowest water absorption coefficient (0.4 g cm−2 at 28 days). Since ilmenite mud is enriched in natural radionuclides, such as radium isotopes (2.0·103 Bq kg−1228Ra and 5.0·102 Bq kg−1226Ra), the IMC-SPCs were subjected to leaching experiments, which showed their environmental impact to be negligible. The activity concentration indices for the different radionuclides in the IMC-SPCs containing 10% and 20% ilmenite mud met the demands of international standards for materials used in the construction of non-residential buildings

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This paper reports the results of a study focused on the production of ceramic tiles from ilmenite mud (MUD), a waste generated by the industry devoted to the TiO 2 pigment production. Ceramic tiles were produced from mixtures of a commercial red stonewaremixture (RSM)with different concentrations of mud (3, 5, 7, 10, 30 and 50 wt%). The samples were sintered to simulate a fast-firing process. The sintering behaviour of the fired samples was evaluated according to ISO methodologiesby linear shrinkage, water absorption and porosity measurements. Both green powder and fired samples were characterised by means of X-ray diffraction (XRD), differential scanning calorimetry (DSC/TG), field emission scanning electron microscopy (FESEM) and bending strength measurements. Moreover, since this activity is a NORM (Naturally Occurring Radioactive Material) industry, the radionuclides activity concentrations were measured by both gamma and alpha spectrometry techniques. Finally, the TCLP leaching test (Toxicity Characteristic Leaching Procedure, USEPA) was performed to assess the risks of the use of undissolved mud tilesfrom an environmental perspective. The results obtained demonstrated that ilmenite mud can be successfully valorisatedin the manufacture of red stoneware ceramic bodies, witheven better technological properties than commercial ones. The addition ofmud as additive (from 3% to 10%) had a beneficial effectto thesintering processes, inproving the bending strength (up to 15 %) and reducing both apparent porosity and water absorption (up to 50%).