Seismic modeling to monitor CO2 geological storage: The Atzbach-Schwanenstadt gas field

We develop a petro-elastical numerical methodology to compute realistic synthetic seismograms and analyze the sensitivity of the seismic response when injecting carbon dioxide (CO2) in a depleted gas reservoir. The petro-elastical model describes the seismic properties of the reservoir rock saturated with CO2, methane and brine, and allows us to estimate the distribution and saturation of CO2 during the injection process. The gas properties, as a function of the in-situ pressure and temperature conditions, are computed with the Peng-Robinson equation of state, taking into account the absorption of gas by brine. Wave attenuation and velocity dispersion are based on the mesoscopic loss mechanism, which is simulated by an upscaling procedure to obtain an equivalent viscoelastic medium corresponding to partial saturation at the mesoscopic scale. Having the equivalent complex and frequency-dependent bulk (dilatational) modulus, we include shear attenuation and perform numerical simulations of wave propagation at the macroscale by solving the viscoelastic differential equations using the memory-variable approach. The pseudo-spectral modeling method allows general material variability and provides a complete and accurate characterization of the reservoir. The methodology is used to assess the sensitivity of the seismic method for monitoring the CO2 geological storage at the Atzbach-Schwanestadt depleted gas-field in Austria. The objective of monitoring is the detection of the CO2 plume in the reservoir and possible leakages of CO2. The leakages are located at different depths, where the CO2 is present as gaseous, liquid and supercritical phases. Even though the differences can be very subtle, this work shows that seismic monitoring of CO2 from the surface is possible. While the identification of shallow leakages is feasible, the detection of the plume and deep leakages, located in the caprock just above the injection formation, is more difficult, but possible by using repeatability metrics, such as the normalized RMS (NRMS) images. Considering real-data conditions, affected by random noise, a reference detection threshold for deep leakages and the CO 2 plume in the reservoir corresponds to a signal-to-noise ratio of about 10 dB.Fil: Picotti, Stefano. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Carcione, José M.. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Gei, Davide. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Rossi, Giuliana. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Santos, Juan Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto del Gas y del Petróleo; Argentina. Universidad Nacional de La Plata; Argentina. Purdue University; Estados Unido

Water reuse: dairy effluent treated by a hybrid anaerobic biofilm baffled reactor and its application in lettuce irrigation

There is a synergy between the large quantities of organics-rich effluents generated by the dairy industry and the continually increasing water needs for crop irrigation. In this sense, this study aimed at evaluating the effect of decreasing the hydraulic retention time (HRT) on the stability and efficiency of a hybrid anaerobic biofilm baffled reactor (HABBR) treating simulated fat- and salt-rich dairy wastewater, followed by its agricultural reuse. The reactor was monitored over 328 days, during which 72, 24, and 12 hours were the hydraulic detention times. After achieving steady-state, the reactor presented organic matter removal above 90% and produced biogas with 41 ± 23%, 53 ± 3%, and 64 ± 12% of methane for HRTs of 72, 24, and 12 hours, respectively. The best process performance was observed for an HRT of 24 h, and thus, a lettuce culture was irrigated with the treated effluent. The irrigation was performed in five different treatments, for which the amount of treated effluent added to tap water varied from 0 to 100%. Both the effluent and the harvested vegetables were evaluated for microbial contamination. Apart from the 75% effluent supply condition, there were no losses in leaf mass or area observed, and instead, there was an increase of these parameters for the 25 and 50% effluent supply treatment. The use of dairy effluent treated by the HABBR allowed for microbiologically safe food production. Therefore, the process offered both potential cost reduction for fertilizers, preservation of water resources, and a renewable energy source.The authors are grateful to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES for the grants to L. K. A. Santos (Finace Code 001) and to M. M. S. Alves (PVE 123/2012, process no. 23038.009805/2012-39), as well for the financial support.info:eu-repo/semantics/publishedVersio

Projection of diametric distribution and carbon stock of a managed forest in Manaus/AM.

Projeção da distribuição diamétrica e do estoque de carbono de floresta manejada na Amazônia. A prognose do crescimento de florestas é importante para o manejo florestal, para o planejamento dos ciclos de corte subsequentes e para mostrar as tendências que a floresta apresentará no futuro. Este trabalho avaliou a utilização de um modelo estocástico - a Cadeia de Markov - na projeção da distribuição diamétrica e do estoque de carbono de uma floresta submetida à exploração seletiva experimental em Manaus/AM

Effect of environmental temperature during the of brooding period on growing period of pullets viscera and tibia

ArticlePoultry production in subtropical and tropical regions faces many problems, one of which is the high air temperature causing thermal stress, particularly dangerous in high-producing birds. Thus, the negative effects caused by heat stress (HS) must be managed. The objective of this study was to evaluate the effects of four different levels of HS in viscera and tibia of pullets. A total of 648 chicks (Lohmann LSL Lite) were used in this study in two different phases. The pre-experimental phase (PEP) was from day 1 through 6 weeks of age. The birds were reared with three different environmental temperatures: thermal comfort, hot and cold. The experimental phase (EP) was conducted from the 7th to the 17th week. Pullets from each thermal environment of the PEP were submitted to: 20 °C, 25 °C, 30 °C, 35 °C. At the end of the 17th week of age 120 pullets were euthanatized and the organs, heart, liver, spleen and gizzard were weighed, as also their tibias. Effects of PEP, and its interaction with EP, were not significant (P < 0.05) for viscera and tibia weight. However, a significant increase (P < 0.05) in heart weight with the decrease of the environmental temperature was observed, being the pullets subject to 20ºC and 25 °C with the heaviest weights. For the liver, pullets subject to the 35 °C had the lowest weight and were different (P < 0.05) from the other three treatments. For gizzard, the difference (P < 0.05) was between the treatments 20ºC and 35 °C. These results indicate that brooding temperatures tested during the first 6 weeks of life did not affect the viscera and bone weight during the growing phase

Dinâmica e estoque de carbono em floresta primária na região de Manaus/AM.

Este trabalho analisou dados de três inventários florestais realizados na área da Floresta Experimental, pertencente à Embrapa Amazônia Ocidental e localizada no km 54 da BR-174, em Manaus/AM. O objetivo foi estudar a dinâmica da floresta - taxas de incremento, recrutamento e mortalidade - além do estoque de carbono, em uma área de floresta primária, sem qualquer tipo de intervenção

Analysis of flight parameters and georeferencing of images with different control points obtained by RPA

ArticleNew techniques for analysing the earth's surface have been explored, such as the use of remotely piloted aircraft (RPA) to obtain aerial images. However, one of the obstacles of photogrammetry is the reliability of the scenes, because in some cases, considerable geometric errors are generated, thus necessitating adjustments. Some parameters used in these adjustments are image overlaps and control points, which generate uncertainties about the amount and arrangement of these points in an area. The aim of this study was to test the potential of a commercial RPA for monitoring and its applicability in the management of and decision-making about coffee crops with two different overlaps and to evaluate geometric errors by applying four grids of georeferenced points. The study area is located in an experimental Arabica coffee plantation measuring 0.65 ha. To capture the images, the flight altitude was standardized to a 30 m altitude from the ground, and a constant travel speed of 3 m s -1 was used. The treatments studied were two combinations of image overlap, namely, 80/80% and 70/60%. Six points were tracked through Global Navigation Satellite System (GNSS) receivers and identified with signs, followed by an RPA flight for image collection. The obtained results indicated distinct residual error rates pointing to larger errors along Cartesian axis Y, demonstrating that the point distribution directly affects the residual errors. The use of control points is necessary for image adjustments, but to optimize their application, it is necessary to consider the shape of the area to be studied and to distribute the points in a non-biased way relative to the coordinate axes. It is concluded that the lower overlap can be recommended for use in the flight plan due to the high resolution of the orthomosaic and the shorter processing time

Produção de biossurfactante por linhagens de pseudomonas isoladas do solo rizosférico no Semiárido da Bahia, Brasil

The aim of this study was to select biosurfactant-producing bacterial strains from soils of plants in the semi-arid region of the state of Bahia, Brazil. The mineral salt medium (MSM) was used as base medium, changes being made in the glucose concentration, temperature, and pH during the optimization process. Two biosurfactant-producing bacterial strains were isolated from the soil of Actinocephalus sp. and belonged to the genus Pseudomonas. The emulsification indexes of these strains rose until 58%. They reduced surface and interfacial tensions of culture medium and crude oil to less than 33 mN/m and 3 mN/m, respectively. This study represented an unprecedented discovery of surfactant activity of the bacterial strains isolated from rhizospheric soils of plants from Northeast Brazilian semi-arid region.O objetivo deste estudo foi selecionar linhagens bacterianas produtoras de biossurfactante do solo rizosf&eacute;rico de plantas na regi&atilde;o semi&aacute;rida do estado da Bahia, Brasil. O meio salino mineral (MSM) foi usado como meio base, sendo realizadas mudan&ccedil;as na concentra&ccedil;&atilde;o de glicose, temperatura e pH durante o processo de otimiza&ccedil;&atilde;o. Duas linhagens produtoras de biossurfactante foram isoladas do solo rizosf&eacute;rico de Actinocephalus sp. e pertencem ao g&ecirc;nero Pseudomonas. Os &iacute;ndices de emulsifica&ccedil;&atilde;o destas linhagens aumentaram at&eacute; 58%. As linhagens de Pseudomonas reduziram as tens&otilde;es superficial e interfacial do meio de cultura e do &oacute;leo cru para menos de 33 mN/m e 3 mN/m, respectivamente. Este estudo representou uma descoberta in&eacute;dita da atividade surfactante de linhagens bacterianas isoladas de solo rizosf&eacute;rico de plantas da regi&atilde;o semi&aacute;rida, no Nordeste Brasileiro