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This paper analyzes the ability of the SCG for briquettes production based on the use of xanthan gum as binder under low pressure and low temperature biomass manufacturing conditions. Briquettes were manufactured at room temperature, at 10, 15, 20, 25 and 30% of moisture content and 8, 10 and 12 MPa of compaction pressure. Raw SCG samples reached dry densities between 0.669 and 0.735 g/cm 3 for the samples with a moisture content of 15% and 8 MPa, and 10% and 12 MPa, respectively. Samples treated with 10% of xanthan gum got densities between 0.672 and 0.819 g/cm 3 depending on the moisture content and the compaction pressure. No one of the raw SCG combinations passed the durability test meanwhile xanthan ones with 30% of moisture content obtained the best results with a loss of mass of 9.1% for the combination compacted at 10 MPa. Raw SCG samples showed water absorption values between 0.498% and 0.846% meanwhile xanthan samples water absorption oscillated between 0.427% and 1.065%. Xanthan gum increased the SCG ashes content from 0.66% to 0.97% and decreased the Lower Heating Value (LHV) from 25,399 J/g of the pure raw SCG to 23,503 J/g. Thermogravimetric tests showed that xanthan gum mix compared to the raw SCG increased as well the volatile peak from 61.54 mW to 81.94 mW as the mass loss rate in the volatile stage from-0.0178 mg/s to-0.0184 mg/s.

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We review the results of the geodetic and structural studies carried out on La Palma Island using geodetic and geophysical data during the period 1992-2007. InSAR and GPS observation techniques were applied to study the existence of deformation on the island and gravity observations were carried out for structural studies. Gravity data were inverted using a nonlinear three-dimensional gravity inversion approach to obtain the geometry of the anomalous bodies constructed in a random growth process with respect to an exponentially stratified background. The main structural feature is a large central body (under the Caldera de Taburiente) with high density, which was interpreted as the Pliocene-age uplifted seamount and a relatively dense intrusive plutonic complex/magma body. The Cumbre Vieja series is characterized by elongated minima distributed according to the rift structure. InSAR results show a clear subsidence located on the Teneguı´a volcano, where the last eruption took place in 1971. A thermal source is the most probable origin for this deformation. A GPS network composed of 26 stations covering the total island surface was set up. Vertical displacements determined comparing the GPS coordinates obtained in 2007 with coordinates determined in 1994 are consistent with the InSAR results obtained in the southern part of the island. This is not the case for the northern part. From the comparison of 2006 and 2007 coordinates it is clear that more time is needed to obtain significant displacements, but observed trends are also consistent with InSAR results. All the observed significant displacements are in stations located outside of the large high-density central body.

The management of construction and demolition wastes is a huge challenge for most Governments. The greatest component of such wastes is concrete and masonry fragments or remains. Among the most common approaches to valorization of such wastes is to convert them to recycled aggregates, however this may be hampered by low quality of some recycled aggregates compared to natural aggregates. This paper presents the results of experimental investigation where concrete and ceramic remains were used to partially substitute clay soil in producing unfired bricks. The bricks were then tested for mechanical strength, water absorption freeze-thaw resistance. Additionally the environmental impact of the bricks was assessed based on Life Cycle Analysis (LCA).

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