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Summary Extraheavy-oil (XHO) reservoirs in South America represent some of the largest hydrocarbon accumulations (>500 billion bbl) in the world. Primary production (PP) that uses long horizontal wells is a commercially proved technology for XHO reservoirs. The expected ultimate recovery with primary production is generally less than 12% of original oil in place (OOIP), and thermal enhanced oil recovery (EOR) is critical for increasing recovery to 30–60% OOIP. Economic and environmentally viable thermal development of these reservoirs will require the use of horizontal steam injectors. Our results reveal that continuous steam injection (CSI) with a horizontal injector placed vertically above a horizontal producer (CSI-HIHP) is a very effective method for XHO reservoirs, with high peak-oil rate and significantly high recovery. This study, the first of its kind for an XHO reservoir, outlines an integrated work flow to evaluate the production potential of a large XHO greenfield with PP followed by thermal exploitation. The work flow, based on a probabilistic framework [involving design of experiment (DOE), proxy methods, and Monte Carlo simulations], evaluates reservoir performance for the whole life cycle of the field under a range of uncertainties, and quantifies the impact of key parameters affecting the reservoir performance. XHO reservoirs usually have significantly higher pressures than typical conventional heavy-oil reservoirs, where CSI has been applied commercially. Therefore, pressure in these reservoirs must be reduced before CSI can begin. Cyclic steam stimulation (CSS) after the initial stage of PP can be used to accelerate pressure reduction in the reservoir, while providing additional recovery. Our results demonstrate that geological features such as shale baffles have a significant impact on delaying pressure reduction during PP and CSS. Under a broad range of conditions investigated in this study, PP for 1 year followed by CSS for 4 years has been found to be successful in reducing pressure to the target pressure for CSI. High pressure drop in the horizontal steam injector can cause pressure near the toe region of the injector to be lower than the producer pressure. This results in poor steam injection and poor steam-chest development in that region, thus greatly reducing the efficiency of the thermal-recovery process. We quantify pressure drop in a horizontal steam injector and its impact on the thermal performance and suggest a novel well configuration that uses two injectors for every long producer during CSI. The proposed configuration with a sequential development plan can significantly improve economics of the projects. A novel probabilistic work flow for a full-field (FF) development plan (PP, CSS, and CSI) of XHO reservoirs provides robust production forecast during the entire life cycle. The work flow developed and the insights obtained would be very valuable in preparing effective exploitation plans and optimal facility design, a key economic variable in large projects of developing giant XHO reservoirs.

Background The main goal of this contribution was to define the ecological niche of the guanaco (Lama guanicoe), to describe potential distributional changes, and to assess the relative importance of niche conservatism and divergence processes between the two lineages described for the species (L.g. cacsilensis and L.g. guanicoe). Methods We used maximum entropy to model lineage’s climate niche from 3,321 locations throughout continental Chile, and developed future niche models under climate change for two extreme greenhouse gas emission scenarios (RCP2.6 and RCP8.5). We evaluated changes of the environmental niche and future distribution of the largest mammal in the Southern Cone of South America. Evaluation of niche conservatism and divergence were based on identity and background similarity tests. Results We show that: (a) the current geographic distribution of lineages is associated with different climatic requirements that are related to the geographic areas where these lineages are located; (b) future distribution models predict a decrease in the distribution surface under both scenarios; (c) a 3% decrease of areal protection is expected if the current distribution of protected areas is maintained, and this is expected to occur at the expense of a large reduction of high quality habitats under the best scenario; (d) current and future distribution ranges of guanaco mostly adhere to phylogenetic niche divergence hypotheses between lineages. Discussion Associating environmental variables with species ecological niche seems to be an important aspect of unveiling the particularities of, both evolutionary patterns and ecological features that species face in a changing environment. We report specific descriptions of how these patterns may play out under the most extreme climate change predictions and provide a grim outlook of the future potential distribution of guanaco in Chile. From an ecological perspective, while a slightly smaller distribution area is expected, this may come with an important reduction of available quality habitats. From the evolutionary perspective, we describe the limitations of this taxon as it experiences forces imposed by climate change dynamics.

The chemical characteristics of mine tailings, organic amendments (doses), and plants are the critical factors that must be evaluated and monitored to ensure the sustainability of phytostabilization. The aim of this study was to evaluate the mobility of copper (Cu) in mine tailings (MT) of the Zone Central of Chile to which commercial humic substances were added, examining their effect on the uptake of Atriplex halimus. Two commercial humic substances (HS1 and HS2) extracted from leonardite (highly oxidized lignite), of different pH and total organic carbon, were evaluated by adsorption curve for Cu. In columns, soluble Cu, pH, and electrical conductivity in leachates were evaluated for MT, MT + HS1, and MT + HS2, and HS1 and HS2 in doses of 120 mg kg-1. In pot assay, seeds were germinated directly in MT and cultivated for 140 days with the addition of HS2 in 120 and 240 mg kg-1. Mine tailing presents high concentration of Cu (2016 ± 223 mg kg-1, pH 6.3 ± 0.1). The results of sequential extraction indicate that Cu is associated with the sulfide fraction of low risk of mobility. The amount of Cu sorbed by HS1 was higher than that sorbed by HS2, and both humic substances showing better fit to the Freundlich than Langmuir model. Lixiviation of Cu was significantly lower in MT + HS1 (0.166 ± 0.043 mg kg-1) and MT + HS2 (0.157 ± 0.018 mg kg-1) than in MT (0.251 ± 0.052 mg kg-1). Copper concentration in plants reached 185.8 ± 37.8 mg kg-1 in the roots and 32.6 ± 7.4 mg kg-1 in the aerial parts cultivated in MT without effect of the humic substance addition in Cu uptake nor growth. Copper concentrations in the aerial parts were adjusted to sufficient or normal levels in plant. A good management of mine tailings through phytostabilization could consider an adequate mixture of humic substances (to avoid leaching of metals) and an organic amendment that provides essential nutrients and increases biomass generation.

This project aims to enlarge the impact of small-scale run-of-the-river hydropower for Turbulent. Turbulent has designed a unique low-head vortex hydropower turbine that creates renewable energy from the flowing of water. To find design opportunities, the company is analysed using stakeholder value mapping, a SWOT analysis, user interviewing, and Business Model Canvases. Independent Power Producers (IPPs) and Single Households are identified as interesting user groups to design for. The insights gained from interviews with IPPs are grouped in a strategic roadmap. The main insights for the IPP market revolve around the topics of partnerships, feasibility and viability studies, certification, manufacturing, and product offering. For the single household market, a new way of working is proposed, where local contractors do most of the contact with single household clients. A customer journey for both single household clients as well as contractors is made to design a website. This website is used to test the market demand for single household turbines. Potential clients can pre-order a pico turbine (less than 5 kW) on this website (turbulentpico.be). Different price points are tested. It is found that there is enough demand for pico turbines that the design and engineering phase of the pico turbines can be started. It is recommended to start Turbulent Pico as a separate company. ; Strategic Product Design

Voor het beheer van verharde oppervlakken wordt hier aandacht geschonken aan de betekenis en de voordelen van toepassing van DOB: Duurzaam OnkruidBeheer op verhardingen

Synthesis of cork-derived ceria ecoceramic, an emerging porous catalyst, for enhancing solar thermochemical water splitting.

Bridgeman (2017) describes the important role of population growth in contributing to environmental problems. The present essay argues that population is an important component of human impact on the environment, but it must be considered in combination with consumption rates. A place-based approach, examining the local context for reproductive decisions, is necessary to assess population growth as a contributor to environmental impact and to develop appropriate behavioral interventions. (PsycINFO Database Record

A non-fullerene acceptor with a high relative dielectric constant (εr) over 9 is developed. It offers an efficiency of 8.5%, which is the best result for organic solar cells employing high εr materials. Further research should focus on morphology optimization to make high εr practically useful in devices.