The Saskatchewan Research Council (SRC) is a provincial treasury board crown corporation engaged in research and technology development on behalf of the provincial government and private industry. It focuses on applied research and development projects that generate profit. Some of its funding comes from government grants, but it generates the balance from selling products and services. With nearly 300 employees and $137 million in annual revenues, SRC is the second largest research and technology organization in Canada.
This study focuses on the spatial variation in seed germination characteristics of Picea glauca and P. mariana, prominent and widespread species within the Canadian boreal forest. The main objective was to determine seed germination requirements of geographically distinct seed collections of P. glauca and P. mariana. A total of 73 collections of P. glauca and 62 collections of P. mariana were selected across Canada and tested for germination under various temperatures. Base temperature (Tb) and thermal time required to reach 50% germination (TH50) were derived from thermal model parameters for all seed collections. Correlation analyses between seed germination traits, geographic, and climatic variables were conducted. Base temperatures for germination of P. glauca ranged from 5.2 to 11.9 °C while P. mariana had base temperatures ranging from 6.2 to 12.8 °C, indicating a broader temperature range for the former to initiate germination. Optimal germination temperatures ranged from 15 to 20 °C for P. glauca and from 17.5 to 30 °C for P. mariana. Thermal time requirements for 50% germination were higher for P. glauca than for P. mariana, indicating that the former takes longer to germinate under the same temperature conditions. Latitudinal-related variables such as temperature of sites had a stronger influence on germination relative to precipitation or potential evaporation and affected seed viability, final germination and germination capacity of all seed sources. Seed viability was lower in northern seed collections and germination capacity was diminished at lower temperatures for both species. The results from this study can be built into models predicting shifts in boreal forest species under climate change.
Current methods for mining low-grade deposits are expensive and resource-intensive, requiring vast amounts of energy, water, and land use. These methods often involve hazardous chemical processes as well as the creation of large tailings ponds. Pre-concentration is the removal of gangue prior to processing and offers a more sustainable mining alternative by reducing the volume of rock subjected to downstream processing, offering both economic and environmental benefits. Minerals exhibit diverse properties (e.g., density, gamma-ray emissions, optical, thermal, magnetic, and structural) that can be exploited using various pre-concentration technologies. Advances in smart sensors, Internet of Things (IoT), Artificial Intelligence (AI), and wireless communication have enhanced industrial sorting, enabling real-time monitoring of mineral characteristics. Selecting the optimal sensor and sorting algorithm depends on aligning mineralogical differences with sensor capabilities. Understanding sensor measurement methods, resolution, and deployment is essential for effective application. To date, the application of automated mineralogy images and centimeter (meso) -scale analysis for pre-concentration and sorting has not been fully investigated. The goal of this work is to demonstrate the potential of meso-scale analysis by presenting the rationale for sensor selection in three case studies, each with a different target commodity: an orogenic gold deposit, a volcanic massive sulfide (VMS) deposit, and a rare earth element (REE) deposit. These case studies demonstrate that appropriate sensor selection can remove 50–98
Precious metal recovery from secondary sources has received significant attention due to the reduced availability of precious metals from conventional sources. Herein, chitosan (CHT) was modified via cross-linking with glutaraldehyde (glu) to yield CHT-glu adsorbents with improved physicochemical and adsorption properties with precious metal ions (Au(III) and Pd(II)). CHT-glu adsorbents were prepared at variable glu ratios and characterized via complementary spectral (IR, 13C solids NMR, XPS) and thermogravimetry methods. The adsorbents display remarkably enhanced properties relative to CHT upon incremental cross-linking, which includes structural stability in acidic media, greater porosity and surface area with unparalleled adsorption at pH 2. The highest metal-ion uptake capacity for the CHT-glu adsorbent system was 1322 mg/g (Au(III)) and 1337 mg/g (Pd (II)). Electrostatic and chelation interactions govern the adsorption mechanism of gold and palladium species by CHT-glu, as supported by XPS results. The CHT-glu systems display superior solid phase extraction properties for the recovery of precious metals from acidic leachate, which is relevant to sustainable metal recovery from tailings or industrial wastewater effluent.
Seven spent-catalyst samples from low-temperature Fe-based Fischer-Tropsch (FT) synthesis were investigated by Mössbauer spectroscopy at room temperature. The calcined precursor catalysts were prepared by three different methods: the historical Ruhrchemie method (3 samples), the organic-acid method (2 samples), and the goethite method (2 samples). The Mössbauer spectra were fitted, using Voigt-based line shapes, to two paramagnetic doublets and five magnetic sextets. The doublets are assigned to Fe2+ (larger quadrupole splitting) and Fe3+species, whereas the sextets are ascribed to the Hӓgg carbide (χ-Fe5C2) (fitted with three sextets having hyperfine magnetic fields of 22, 18, and 10 T) and magnetite (Fe3O4) with its characteristic two-sextet pattern with hyperfine magnetic fields of 48 T (A-site) and 45 T (B-site). The Mössbauer relative areas, which give the relative proportions of Fe-containing phases, indicate that the catalyst samples prepared by the Ruhrchemie method contain large amounts of Fe-carbide (presumably the active phase in FT synthesis) compared to those prepared by the organic-acid and goethite methods. Furthermore, the Fe-carbide Mössbauer area is positively correlated with the calcined catalyst precursor surface area, which was found to positively correlate with the FT activity. The results indicated that the Ruhrchemie method is superior to the organic-acid and goethite methods for producing large proportions of Fe-carbide and thus high-performance low-temperature FT catalysts.
Solvent-assisted SAGD (SA-SAGD) has been studied as an alternative to improve the efficiency of SAGD. This paper reports a new set of experimental data for SA-SAGD and analyzes the characteristics of bitumen-solvent mixing in the experiments using history-matched numerical models. The dimensions of the sand pack were 3 in. in diameter and 15 in. in length, and the sand pack was contained in a 25-L cylindrical pressure vessel. An annular void space surrounded the sand pack with a gap thickness of 1 in., within which a steady state flow of the injected vapor phase maintained the controlled pressure, temperature, and composition. Therefore, the gravity drainage in the sand pack occurred at a set of specified thermodynamic conditions for the surrounding annular steam chamber, unlike transient conditions near the edge of a steam chamber in larger-scale steam injection processes. In addition to SAGD as the base case, five sets of SA-SAGD were performed: 20 mol% C4, 40 mol% C4, 10 mol% C8, 20 mol% C8, and 10 mol% condensate coinjected with steam at 3500 kPa. The peak oil production rate was 9.84 cm3/min with SAGD, 14.61 cm3/min with 20 mol% C4-SAGD, 16.34 cm3/min with 40 mol% C4-SAGD, 31.33 cm3/min with 10 mol% C8-SAGD, 12.36 cm3/min with 20 mol% C8-SAGD, and 12.33 cm3/min with 10 mol% condensate-SAGD. SAGD was the least effective in bitumen gravity drainage, while the 10 mol% C8-SAGD was the most effective. Increasing the C4 molar concentration from 20 to 40 mol% slightly increased the peak rate; however, the peak rate in C8-SAGD significantly was decreased by increasing the C8 concentration from 10 to 20 mol%. This counter-intuitive result was reported in a few simulation studies with heavy solvents (e.g., C7 and C12) in the literature, but had not been experimentally confirmed before this research. Although the condensate contained 93 mol% C7-like pseudo component (C7, eq), the peak rate of 10 mol% condensate-SAGD was much smaller than that of 10 mol% C8-SAGD. These experimental observations highlight the practical importance of understanding the sensitivity of bitumen gravity drainage to heavy-solvent concentrations near the edge of a steam chamber in SA-SAGD.
