Caratterizzazione delle risorse geotermiche del bacino geotermico dell’area vulcanica orvietana

Il contributo alla ricerca erogato dalla Regione Umbria al dipartimento DICAM dell\u2019Universit\ue0 di Bologna \ue8 finalizzato ad una ricerca di interesse comune intitolata: \u201cBacino geotermico dell\u2019area vulcanica orvietana. Caratterizzazione della risorsa per lo sviluppo idrotermale del bacino geotermico\u201d. L\u2019attivit\ue0 di ricerca prevede di caratterizzare il flusso dei fluidi di strato del bacino geotermico dell\u2019area Orvietana. Lo studio prevede la ricostruzione del modello geologico (modello concettuale) attraverso dati reperibili in letteratura e / o forniti dalla Regione Umbria. Il modello concettuale del bacino geotermico \ue8 implementato poi in un modello numerico per la successiva simulazione dei processi di flusso di massa e calore, eseguita con il codice numerico TOUGH2 (Pruess, 1999) utilizzando l\u2019equazione di stato EWASG, che tiene conto di gas non condensabili (CO2) e soluzioni saline ad alta temperatura e pressione (coerentemente con le caratteristiche dei reservoir geotermici oggetto di studio). La ricerca \ue8 suddivisa nelle seguenti tre attivit\ue0: 1. Nella prima si procede alla costruzione del modello concettuale, attraverso la raccolta ed elaborazione dei dati presenti in letteratura e di dati di pozzo, ove disponibili. In questa fase la regione Umbria collaborer\ue0 fornendo i dati in suo possesso; 2. Nella seconda si realizza il modello numerico. In assenza di curve di produzione e log dinamici, la calibrazione \ue8 stata necessariamente eseguita mediante le simulazioni dello stato stazionario (steady state). Il modello dovr\ue0, per quanto possibile, essere in grado di riprodurre i gradienti geotermici ottenuti dai dati di letteratura. 3. La terza prevede la realizzazione di alcuni scenari di sfruttamento per la valutazione della capacit\ue0 produttiva del bacino geotermico e della sua risposta, in termini di depauperamento termico e idrico. In questa fase DICAM ha concordato con la Regione Umbria le caratteristiche delle possibili modalit\ue0 di prelievo da simulare

Análise de imagem para a qualificação dos produtos e para o aumento da competitividade

Este artigo descreve as vantagens que uma técnica objectiva como a análise de imagem pode trazer à valorização dos produtos das rochas ornamentais e consequentemente aumentar a competitividade das empresas do secto

L'analisi di immagine per la qualificazione del prodotto

La competitività internazionale richiede ai prodotti finiti europei, ed italiani in particolare, di giustificare con un valore aggiunto il maggior costo con cui sono offerti sul mercato. Sicuramente l’introduzione di nuova tecnologia può offrire la possibilità di ridurre i costi, ma non è pensabile arrivare ad essere competitivi in termini di costo con Asiatici o anche Latino-Americani. La tecnologia da introdurre, dunque, deve essere mirata a qualificare il prodotto finito, a fornire valore aggiunto. L’aspetto visivo è la caratteristica fondamentale di una roccia ornamentale che conferisce valore ed è ricercata dal cliente. Le Norme CEN ed i tecnici del settore sono molto attenti alle caratterizzazioni fisico meccaniche del prodotto finito, ma c’è da domandarsi quante volte una partita è stata contestata perché il peso specifico o la resistenza a compressione non erano conformi a quanto dichiarato. Vi è da domandarsi se un cliente sceglie un marmo di Carrara od un marmo cinese perché hanno una differente resistenza allo shock termico o perché hanno un differente costo; se è preferito un verde brasiliano per un pavimento a causa della gelività o per l’aspetto estetico. Ancora oggi le specifiche di prodotto (EN 12058), per la definizione di un metodo di misura dell’omogeneità delle piastrelle, non ricorrono ad un metodo “scientifico” e imparziale, oggettivo per la misura di una caratteristica così complessa quale l’aspetto visuale di un materiale. La stessa marcatura CE ignora la qualità estetica

Deliverable 2.1 - GEOTeCH Project - Report on the evaluation of available information

The WP2 of the Geotech H2020 project has the following objectives: - Develop (design, test and produce) Hollow Stem Augers (HSA) for the installation of the concentric spiral heat exchanger developed in WP3. - Develop (design, test and produce) the associated auxiliary equipment for the HSA, that will allow efficient and cost effective operation and installation of the concentric heat exchanger developed in the Geotech project. - Develop (design, test and produce) a drill rig platform that integrates the HSA and its auxiliary equipment in an operator friendly and production efficient tool. - Investigate and test the potential application of the drill rig and auger equipment for the installation of the concentric spiral heat exchanger in foundation applications. The deliverable 2.1. publication first of all provides a general overview of the current state of the Ground Source Heat Pump (GSHP) technology based on shallow closed loop heat exchanger application. In addition, the technical and legislative requirements for GSHP installation in a number of countries are reviewed, indicating that a certain level of market introduction and awareness of the technology is present. In addition, the potential future role of Ground Source Heat Pumps (GSHP) as a renewable technology is positioned in the light of the RES directive and the National renewable energy action (Nreap) plans. Secondly, the deliverable 2.1. evaluates the currently available drilling and installation methods that are in use for installing vertical closed loop heat exchangers. This is done to assert the suitability of the proposed Hollow Stem Auger (HSA) for the installation of shallow heat exchangers, specifically the concentric spiral heat exchanger developed in the Geotech project. A similar task is undertaken to evaluate the role of the HSA and the concentric spiral heat exchanger in installing thermally activated foundations. Thirdly, using the information from the previous evaluation and from practical experience, the requirements and prototype design of the HSA, the drill rig and the auxiliary equipment required to successfully install the concentric spiral heat exchanger are stated. The objective of this section of the deliverable is to develop outline guidance and performance specification for actual prototyping of components that will be used for evaluation in the following phases of production and testing. The deliverable 2.1. concludes: The current and future position of GSHP \u2022 As an energy savings technology using renewables, GSHP clearly has a future role in combination with either renewable energy production (wind, solar, biomass) or with conventional energy production. Furthermore GSHP can store thermal energy. \u2022 Evaluating the current drilling and installation technology for vertical closed loop heat exchangers indicate that a dry drilling technique such as HSA has a number of distinct advantages when compared to conventional drilling systems using air or water as a flushing medium. \u2022 In the foundation application the main gain of the HSA and drill rig development will be in the ease of installation of the concentric spiral heat exchanger, allowing thermal activation of foundations with only very limited extra cost when compared to a conventional foundations. The outline specifications for the HSA, drillrig and auxiliary equipment \u2022 Automated, operator friendly drilling process \u2022 Installation capability for different diameter (63 \u2013 200 mm) spiral heat exchangers in all non consolidated formations to a maximum of 50 to 60 meters of depth. \u2022 Based on previous experience and a very limited data set it is concluded that the torque and RPM requirement for successful HSA application should be in the region of 8.000 \u2013 12.000 Nm (torque) and 25-150 RPM. \u2022 Experience based requirements from the foundation application section of this report underwrite these requirements for the successful use of augers for micropiling. \u2022 Limited amounts of water used in drilling process, direct processing of drilling spoil

In-situ GPR test for three-dimensional mapping of the dielectric constant in a rock mass

The Ground Penetrating Radar (GPR) is used to detect subsurface anomalies in several applications. The more the velocity of propagation or the dielectric constant is estimated accurately, the more the detection of anomalies at true subsurface depth can be accurately obtained. Since many GPR applications are performed in rock mass with non-homogeneous discontinuous nature, errors in estimating a bulk velocity of propagation or dielectric constant are possible. This paper presents a new in-situ GPR test for mapping the dielectric constant variability in a rock mass. The main aim is to investigate to what extent the dielectric constant is variable in the micro and macro scale of a typical rock mass and to give attention to GPR users in rock mass mediums. The methodology of this research is based on the insertion of steel rods in a rock mass, thus acting as reflectors. The velocity of propagation can be then modeled, from hyperbolic reflections, in the form of velocity pathways from antenna positions to a buried rod. Each pathway is characterized by discrete points which are assumed in three dimensions as centers of micro cubic rock mass. This allows converting the velocity of propagation into a dielectric constant for mapping and modeling the dielectric constant in a volumetric rock mass using a volumetric data visualization software program (Voxler). In a case study, 6 steel drilling rods were diagonally inserted in a vertical face of a bench in a sandstone quarry. Five equally spaced parallel lines, almost perpendicular to the orientations of the rods, were surveyed by a dual frequency GPR antenna of 200 and 600 MHz. The results show that the dielectric constant is randomly varied within the micro and macro scale either in single radargrams or in the volumetric rock mass. The proposed method can be useful if considered in signal processing software programs, particularly in presence of subsurface utilities with known geometry and dimension, allowing converting double travel time, through portions of a radargram, into more reliable depths using discrete dielectric constant values instead of one value for a whole radargram

Interpretation of production tests in geothermal wells with T2Well-EWASG

In the geothermal sector, being able to simulate production tests by combining surface and downhole measurements can be extremely useful, improving data interpretation and reducing the impact of unavailable field data. This is possible with T2Well, a coupled wellbore-reservoir simulator. We plugged the EWASG equation of state for high enthalpy geothermal reservoirs into T2Well and extended the function to analytically compute the heat exchange between wellbore and formation at the short times. Changes to the analytical heat exchange function were verified by comparison with wellbore-formation heat exchange numerically simulated. T2Well-EWASG was validated by reproducing the flowing pressure and temperature logs taken from literature, and by using the software for the interpretation of a short production test. Simulation results indicate that T2Well-EWASG can be effectively used to improve the interpretation of production tests performed in geothermal well