Increasing demand for energy due to the populous Eastern Australia has driven oil and gas industries to find new sources of hydrocarbons as they are the primary energy suppliers.Intensive study has been done on the Vo...Increasing demand for energy due to the populous Eastern Australia has driven oil and gas industries to find new sources of hydrocarbons as they are the primary energy suppliers.Intensive study has been done on the Volador Formation in the Gippsland Basin by means of core-based petrophysical,sedimentological,and petrographic analyses as well as well log-based interpretation and capillary pressure test.Five wells from Kipper,Basker and Tuna fields with available dataset were investigated in this study:Kipper-1,Basker-1,Basker-2,Basker-5 and Tuna-4.Overall,the formation has good reservoir quality based on the high porosity and permeability values obtained through core and well log petrophysical analyses.The formation made up of mostly moderate to coarse quartz grains that has experienced strong anti-compaction and is poorly cemented.Montmorillonite and illite clays are seen dispersed in the rock formation,with the minority being mixed clays.These clays and diagenetic features including kaolinite cement and quartz overgrowth that can lead to porosity reduction only have insignificant impact on the overall reservoir quality.In addition,capillary pressure data shows that most samples are found in the transition to good reservoir zones(<50%saturation).The results obtained from this study have shown that the Volador Formation in the Gippsland Basin is worth for hydrocarbon exploration.展开更多
To shed light on the genesis of the Dongping deposit and reveal the behaviour of CO_(2),Au and other ore elements(e.g.,Cu,Fe,Zn,As,Sb,Co etc.)in ore-forming fluids,petrographic,microthermometric and synchrotron radiat...To shed light on the genesis of the Dongping deposit and reveal the behaviour of CO_(2),Au and other ore elements(e.g.,Cu,Fe,Zn,As,Sb,Co etc.)in ore-forming fluids,petrographic,microthermometric and synchrotron radiation X-ray fluorescence(SRXRF)analyses of fluid inclusions were conducted.The ore-forming fluid is characterized as an H_(2)O-CO_(2)-NaCl system with medium-high temperatures and low salinity.Four mineralization stages are identified,namely,feldsparquartz(stage 1);pyrite-white quartz(stage 2);sulfide-smoky grey quartz(stage 3);and carbonate-quartz(stage 4).Three types of inclusions were distinguished,based on fluid composition,phase assemblages and mode of homogenization.Type A:H_(2)O-rich fluid inclusions show 2 phases(liquid H_(2)O(LH_(2)O)+vapour H_(2)O(VH_(2)O))at room temperature and homogenize to the liquid phase.Type B:H_(2)O-CO_(2)fluid inclusions contain 2–3 phases(liquid H_(2)O(LH_(2)O)+vapour CO_(2)(VCO_(2));liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2)));liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2))+vapour CO_(2)(VCO_(2)))at room temperature and homogenized to the liquid H_(2)O phase.Type C:H_(2)O-CO_(2)fluid inclusions show 2 phases(liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2))at room temperature and homogenize to a critical state.CO_(2)is clearly more enriched in the fluid inclusions of stages 2 and 3 than in stage 1.Stage 1 is dominated by type A(H_(2)O-rich)inclusions with homogenization temperatures(Th)of 220–359℃and salinities of 1.1–3.1 wt%NaCl equivalent.Type B(CO_(2)-rich)inclusions gradually increase in stages 2 and 3.The Th range of type B inclusions in stage 2 is 241–397℃with salinities of 2.2–6.9 wt%NaCl equivalent;the Th range of type A inclusions is 217–373℃with salinities of 1.2–8.1 wt%NaCl equivalent.The Th range of type B inclusions in stage 3 is 215–361℃with salinities of 2.9–6.1 wt%NaCl equivalent;the range of type A inclusions is 158–351℃with a salinity of 0.7–5.5 wt%NaCl equivalent.Stage 4 is characterized by type A with Th of 151–250℃and salinities of 0.9–8.3 wt%NaCl equivalent.The mapping results show that elements As,Te and Sb are more concentrated in vapour CO_(2)than in liquid H_(2)O at room temperature,which suggests that vapour components are more able to transport elements when phase separation occurs.The SRXRF quantitative results show that Au,Cl,S and some other metals are obviously more enriched in the fluid inclusions of stages 2 and 3 than those in stage 1.Additionally,the contents of S in stages 1–3 are much lower than those of Cl,which suggests that gold might migrate mainly in the form of a gold-chloride complex.Au is more enriched in type B fluid inclusions than in type A fluid inclusions,which suggests that the enrichment and migration of gold are closely related to CO_(2)and CO_(2)plays a critical role in the migration and enrichment of gold.The trace elements in the fluid have a similar change trend to those in the Yanshanian syenogranite distributed in the southeastern part of the mining area,which may provide some evidence for an intrusion-related genesis for the Dongping gold deposit.展开更多
Zatua Hills are located at Haut Uélé Province of Democratic Republic of Congo (DRC), between northern Bafwasende and southern Paulis (Isiro) Squarred Degrees. Belonging to greenstone belt of Ngayu, that area...Zatua Hills are located at Haut Uélé Province of Democratic Republic of Congo (DRC), between northern Bafwasende and southern Paulis (Isiro) Squarred Degrees. Belonging to greenstone belt of Ngayu, that area is identified by the high elevated zone which is remained the witness of stable zone, not affected by the ancienst erosion process. Zatua Hills are in the superior Kibalian formation dated to Neoarchaen, hosted in Upper Congo Granites Massifs of DRC covering a large central zone of NE of DRC, and consisting to dolerite, phyllade, clay rich sediment, poor Banded Iron Formations (BIFs), enriched BIFs, friable hematite, hard hematite, mineralized and unmineralized brechias. Magnetite, martite and hematite are associated to some secondary minerals such as goethite, gibbsite, kaolinite, strengite, variscite and others clay minerals present in BIFs. Petrographic analysis made from the samples collected in situ showed, as well as BIFs and iron ore associated, that magnetite was much abundant oxide mineral which is oxided to martite before to stabilize to hematite during the deposition time. Having about hundred meters of thickness, the rich iron ore of this area content, in the majority less deleterious elements which, are harmful in metallurgic process of iron. These secondary minerals were precipitated at various degrees in the leached cavities of rocks between martite and hematite aggregates to botryoidal texture and, are rich to Al, and are mainly consisting to gibbsite and solid solution series of variscite-strengite (AlPO<sub>4</sub>·2H<sub>2</sub>O and FePO<sub>4</sub>·2H<sub>2</sub>O). Low degree of metamorphism played when magnetite was converted to martite, with the presence of variscite and anatase like witnesses of this event in which, martite was crystalized to hematite.展开更多
In the French concept of deep nuclear waste repositories,the galleries should be backfilled with excavated argillite after the site has been filled.Some additives like lime could be used to improve the mechanical char...In the French concept of deep nuclear waste repositories,the galleries should be backfilled with excavated argillite after the site has been filled.Some additives like lime could be used to improve the mechanical characteristics of the argillite.After thousands of years,the degradation of the concrete lining of the galleries will generate an alkaline solution(pH value 12) that will diffuse through the backfill.This study presents the effect of a saturated Ca(OH)_2 solution circulation through lime-treated sample at 60 ℃ for 3,6 and 12 months,respectively.The effect of such circulation on the lime-treated Manois argillite(MA) was assessed by petrographical examination coupled to image analysis and scanning electron microscopy(SEM) equipped with energy dispersive X-ray(EDX) analyser of soil pieces.The objective of this study is to make the link among the mineralogical transformations,the textural and mechanical changes produced in the compacted clayey soil as a consequence of the alkaline solution circulation.展开更多
In this paper, we described the petrographical characters of the Mn-bearing rock types outcropping in the Kalakhuta, Ghatia, Gararia, Itala, Wagaicha, Tambesara and Talwara villages of Banswara district. The Mn associ...In this paper, we described the petrographical characters of the Mn-bearing rock types outcropping in the Kalakhuta, Ghatia, Gararia, Itala, Wagaicha, Tambesara and Talwara villages of Banswara district. The Mn associated rocks in the study area are phyllite, schist, quartzite and limestone. The mineral assemblage in phyllite formed under greenschist facies metamorphism. Petrographic studies of various phyllite samples also reveal that porphyroblasts of biotite sat in the fine-grained micaceous matrix (Biotite, muscovite, chlorite) along with quartz, opaque and ore minerals. Petrographic studies of schist reveal its formation under prograde metamorphism. Mineral assemblages observed in schist are typical of greenschist to lower amphibolite facies. The various schist samples at places show clusters made up of perfect rhombshaped garnets which suggest the increase in the grade of metamorphism. The quartzites are disposed conformably with the phyllites, and are at times brecciated and re-cemented by secondary chert and manganese. These Mn-bearing quartzites are with sutured/serrated and straight grain boundaries. The quartzite samples are fully composed of quartz showing undulose extinction with subordinate feldspar, micas and carbonatic materials. The petrographic characteristics explain that mostly limestones are the dolomitic composition but some ferruginous varieties are also noticed at places. The purer variety of limestone consists of calcite, dolomite and some magnetite but tremolite, quartz and some minute flakes of biotite also occur in impure variety.展开更多
All engineering projects consist of several steps, and one of the main tasks is to identify and characterize the most important features of rock types that will be excavated, crushed, or mined for any particular usage...All engineering projects consist of several steps, and one of the main tasks is to identify and characterize the most important features of rock types that will be excavated, crushed, or mined for any particular usage purpose, from a single residential building to major works of infrastructure. Laboratory investigation on engineering geology is thus conducted in order to determine the most relevant rock properties when designing structures such as mining shafts, tunnels, buildings, or reservoir dams to be built in sites associated with rocks. A wide range of laboratory tests is available, making the correct choice of test methods greatly relevant to determine the key property for the planned use of the rock. This paper is an illustrative case of laboratory testing of basaltic rocks to be used as riprap in a reservoir dam. It shows the important role of the petrographic study carried out to analyze the distribution pattern of smectite clay minerals. Test results are explained for the assessment of rock alterability, an essential aspect for the selection of the most suitable basalt variety for the envisaged conditions of use.展开更多
In this paper,the strength and petrographic structure of clinker by low-temperature burning are studied. The results show that both the calcining temperature of Ca-CO3 and sintering temperature clinker decreases by 15...In this paper,the strength and petrographic structure of clinker by low-temperature burning are studied. The results show that both the calcining temperature of Ca-CO3 and sintering temperature clinker decreases by 150 degrees C compared with those in traditional rotary kiln,the rate of f-CaO in the clinker sintered at 1300 degrees C is 0.29% similar to 2.81%, the strength of the clinker is 62. 5MPa with maximum 69. 4MPa at a specific area of 2900 similar to 3400cm(2)/g. The results also show that the types of petrographic structure of the clinker can be classified as: homogeneous structure, inlaid or edged structure,stain-melting structure and porous structure. The clinker sintered at 1300 +/- 15 degrees C temperature and with enough retention period is mainly in homogeneous structure.展开更多
To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of China, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactiv...To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of China, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^+, K^+, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.展开更多
A new method of sintering Ca3SiO5 by the combination of conventional and microwave heating methods was studied. The influence of transitional metal oxides such as Fe2O3, Cr2O3, MnO2, and V2O5 used as the additive of m...A new method of sintering Ca3SiO5 by the combination of conventional and microwave heating methods was studied. The influence of transitional metal oxides such as Fe2O3, Cr2O3, MnO2, and V2O5 used as the additive of microwave absorption on the microwave-promoted burning of Ca3SiO5 was investigated. The experimental results indicate that the new burning technique is capable of promoting the sintering of Ca3SiO5. At 1200-1300℃ in an electric furnace, Ca3SiO5 can be obtained only when the sample is heated in a microwave for 110-240 s, and the free lime content is below 40wt%. Based on the experiments, Fe2O3, Cr2O3, MnO2, and V2O5 can enhance microwave sintering. Amongst them, Cr2O3 is the most effective. The characteristic of the X-ray diffraction peaks of Ca3SiO5 is similar to those of standard Ca3SiO5, but the peaks are wider.展开更多
Studies were taken of ore-bearing rocks, ores and gravity concentrates from Natalka gold deposit by a set of complex methods including mineralogical, petrographic and geochemical research, gravity concentration, and e...Studies were taken of ore-bearing rocks, ores and gravity concentrates from Natalka gold deposit by a set of complex methods including mineralogical, petrographic and geochemical research, gravity concentration, and electronic microscopy. The major form of Au found is native: free gold is larger and dispersed, in the form of microinclusions. The obtained results are the basis for an effective technology to extract gold and sequence of profitable mining of Natalka deposit.展开更多
Geotechnical studies were carried out on soils from Shango-Chanchaga highway in Minna, in relation to the petrographic characteristics of the parent rock. Samples were obtained from 5 trial pits at 1 km interval for g...Geotechnical studies were carried out on soils from Shango-Chanchaga highway in Minna, in relation to the petrographic characteristics of the parent rock. Samples were obtained from 5 trial pits at 1 km interval for geotechnical analysis. The moisture content varies from 35.0% to 58.5%, liquid limit ranges from 29.0% to 43.0%, plastic limit ranges between 9.0% and 26.5%, while plasticity index ranges from 12.0 to 33.5. The optimum moisture content (OMC) ranges from 12.0 to 14.0, and California Bearing Ratio (CBR) ranges from 2 to 21. The diffractograms showed that the dominant minerals were clinochore (Mg,Fe)6(Si,Al)4O10(OH)8, quartz (SiO2), cordierite (Mg2Al4Si5O18Ar0.625), and albite (Na0.98Ca0.02Al1.02Si2.98O18). The results showed that there exists a relationship between the mineral composition, the texture of the rock, and the geotechnical characteristics of the soil types.展开更多
This paper presents the results of petrographic study of sedimentary iron ore from surface strata of the Shendi-Atbara Basin,River Nile State,Sudan.The aims of this study are to investigate the geological behavior and...This paper presents the results of petrographic study of sedimentary iron ore from surface strata of the Shendi-Atbara Basin,River Nile State,Sudan.The aims of this study are to investigate the geological behavior and geological conditions affecting precipitation of sedimentary iron ore.The methodologies have been used to realize the objectives of this study include field work,office work and laboratory work including thin sections and polished sections analysis.According to field observation sedimentary iron ore can broadly be considered as occurring in three major classes:Ferribands iron,ferricrete iron and oolitic iron ores.The modes of occurrence of iron ore were described at the outcrops and vertical sedimentary profiles revealed that the iron occurred in the study area at different types in stratigraphic sequence such as cap,bedded and interbedded conformable with Shendi Formation.Petrographic study of iron ore in collected samples using polarized microscope and ore microscope includes study of the textures and structures of ores to obtain ore history.The main types of textures and structures in studied samples are oolitic,granular,lamellar and bands.According to these results the origin of iron ore is formed by chemical precipitation during chemical weathering of surrounding areas in continental lacustrine environment.The iron ore in study area is potential for future mining works and steel industry.展开更多
Most of the hinterland of the North China platform is devoid of Late Ordovician strata. The BaiyanhuaMountain section at Shetai Town is a standard section of the Upper Ordovician newly established in recentyears at th...Most of the hinterland of the North China platform is devoid of Late Ordovician strata. The BaiyanhuaMountain section at Shetai Town is a standard section of the Upper Ordovician newly established in recentyears at the northernmost margin of the platform. This establishment directly involved the determination of thenorth boundary of the platform and the understanding of its evolutionary Listory. The area is quite differentfrom the binterland of the platform in Middle Ordovician rock types and sedimentary environments, with theformer characterized by frequent slope deposits and the latter consisting almost entirely of platform deposits.The present paper focuses on the petrographic features and sedimentary ervironments of the Middle-UpperOrdovician strata in the area, providing further theoretical support to the establishment of the section and fil-ling the gap in this respect.展开更多
The Bethampudi layered anorthosite complex at the border zone of Archaean supracrustal rocks of Khammam district, Eastern Ghats shows normal stratification predominantly in the form of rhythmic layering and often exhi...The Bethampudi layered anorthosite complex at the border zone of Archaean supracrustal rocks of Khammam district, Eastern Ghats shows normal stratification predominantly in the form of rhythmic layering and often exhibits of zebra layering. Graded bedding and cumulate structures are also noticed. The rocks of the study area are classified based on petrography into anorthositic rocks, gabbroic rocks and ultramafic rocks and amphibolites. The field relations and major element composition suggest that these anorthosite rocks are of calc-alkaline in nature and petrogenitically related to the gabbroic rocks by the fractional crystallization at ℃.展开更多
The geology of the Zango-Daji area was investigated petrographically and geochemically to determine the study area’s rock types and mineralization potential.The study area is underlain by rocks of the basement comple...The geology of the Zango-Daji area was investigated petrographically and geochemically to determine the study area’s rock types and mineralization potential.The study area is underlain by rocks of the basement complex characterized by hilly and undulating rocks,which include granitic gneiss,migmatite gneiss,biotite hornblende granite gneiss,and pegmatites.Observation from the field shows that the study area is dominantly underlain by granitic gneiss.The granitic gneiss is dark grey,medium-coarse-grained,and characterized by weak foliation defined by the alignment of a streak of light and dark coloured minerals.They are widespread in the area constituting about 70%of rock types found in the study area.The average modal percentage of minerals in the rocks from petrographic studies shows that granitic gneiss had quartz 45%,plagioclase 10%,microcline 20%,hornblende 2%,biotite 10%,muscovite 5%,kyanite 8%and other minerals 5%.Also,the pegmatite of the study area has no evidence of mineralization;it contains minerals like quartz,feldspars(microcline and orthoclase),and micas(mostly muscovite).Geochemical analysis of the granitic gneiss of the study area shows that silica is by far the most abundant with a value of 53.5%,Na_(2)O value of 32.5%,Al_(2)O_(3),and k_(2)O of 6.1%and 4.0%,respectively.CaO value of 2.630%accounts for plagioclase feldspar in the granitic gneiss.The QAP diagram was used to determine the petrogenesis of the granitic gneiss.The plot shows the parent rock was a monzogranite with a low percentage of plagioclase in a thin section with a high percentage of quartz and alkali feldspar.The pegmatites of the study area are barren,as confirmed by the XRD result.展开更多
The characterization of carbonated rocks of Mintom allowed identifying three features (massive limestone, banded limestone and dolomite). Samples taken in these features were subjected to the physico-chemical analyses...The characterization of carbonated rocks of Mintom allowed identifying three features (massive limestone, banded limestone and dolomite). Samples taken in these features were subjected to the physico-chemical analyses and to the mechanical tests. The results obtained show a convergence in the mineralogical composition in particular in the calcareous features (smectite, micas and calcite);the dolomite feature being mainly constituted by dolomite associated with the smectite. The chemical composition allows finding contents raised in CaO, in all the samples. However, in the dolomite and the banded limestone, the concentrations in MgO and in SiO<sub>2</sub> are also important. The mechanical properties showed a good compression resistance for the massive limestone and the dolomite, the mechanical behavior of the banded limestone being low. The exploitation of these results allows recommending carbonated rocks of Mintom in the production of the clinker, agricultural amendments and in the constructions of the civil engineering.展开更多
Petrographic, physical, and mechanical assessment investigation of NikanaiGhar limestone aggregate exposed in the Lower Dir area of Malakand Division, Pakistan, were conducted to evaluate and investigate its potential...Petrographic, physical, and mechanical assessment investigation of NikanaiGhar limestone aggregate exposed in the Lower Dir area of Malakand Division, Pakistan, were conducted to evaluate and investigate its potential for use as a construction material for engineering projects. Different geotechnical tests and petrographic analyses were performed to evaluate its potential for construction purposes. Geotechnical tests include unconfined compressive strength, ultimate tensile strength test, specific gravity, share strength, porosity, and water absorption. The evaluated physical attributes were compared to standard specifications to determine their suitability as a construction material. Petrographic investigation indicates mainly two types of stones. Stylolitic spar stone and Spar stone are metamorphosed equivalent limestones and are not prone to alkali-silica reactivity. Mutual relationships between physical parameters have been described by simple regression analysis. Significant direct correlation of specific gravity with ultimate tensile strength and uniaxial compressive strength was noted. However, negative trends of Porosity with ultimate tensile strength and uniaxial compressive strength were observed which is in accordance with standard. The analysis revealed that the limestones of NikanaiGhar Formation fall within the standard specification limits and can be used as aggregates for the indigenous construction industry.展开更多
The sand intervals of the Early Cretaceous Lower Goru Formation are a conventional reservoir,generally distributed in the Middle and Lower Indus Basin of Pakistan.Lithostratigraphically formation is classified into tw...The sand intervals of the Early Cretaceous Lower Goru Formation are a conventional reservoir,generally distributed in the Middle and Lower Indus Basin of Pakistan.Lithostratigraphically formation is classified into two parts;the upper parts are predominantly composed of shale,siltstone,and thin layers of alternate shale and sandstone,while the lower parts are composed of sandstone with interlayering of shale and limestone.The sandstone of the Lower Goru Formation has been further divided into A,B,C,and D sand intervals based on reservoir quality.Detailed depositional facies and reservoir characteristics are essential for the evaluation of hydrocarbon exploration and development.This paper aims to evaluate the depositional environment and reservoir characterization of the siliciclastic reservoir of the Early Cretaceous Lower Goru Formation by integrating the gamma-ray log patterns and petrographic analysis and scanning electron microscopic(SEM)analysis.Petrographic characterization of the sand intervals and Gamma-ray log signatures were used for the interpretation of the depositional environment of the reservoir intervals.Petrographic analysis reveals that the sandstone of the Lower Goru Formation is fine-to medium-grained,well-sorted,arkose or feldspathic arenite.Primary intergranular macroporosity,secondary intragranular macropores,and Intercrystalline micropores were identified within the sandstone by the SEM analysis.The diagenetic analysis suggests that the sandstone possesses high porosity,low permeability,and has undergone significant alterations such as compaction,quartz cementation,feldspar dissolution,and clay minerals alteration.Five electrofacies are interpreted based on gamma-ray log patterns including(1)funnel shape(FA);(2)bell shape(FB);(3)cylindrical shape(FC);(4)bow shape(FD);and(5)serrated shape(FE)patterns.The interpreted facies results reveal shoreface environment for A-sand,Tidal flat for B-sand,mixed tidal flat for C sand,Tide dominated mixed for D-sand,and transgressive shelf for Esand.The present study will be helpful for the assessment of the reservoir quality of the Early Cretaceous Lower Goru Formation for further exploration and development in the Indus Basin of Pakistan.展开更多
The shale deposits of Damodar Valley have received great attention since preliminary studies indicate their potential for shale gas. However, fundamental information allied to shale gas re- servoir characteristics are...The shale deposits of Damodar Valley have received great attention since preliminary studies indicate their potential for shale gas. However, fundamental information allied to shale gas re- servoir characteristics are still rare in India, as exploration is in the primary stage. In this study, Ba- rakar shale beds of eastern part of Jharia Basin are evaluated for gas reservoir characteristics. It is evident that Barakar shales are carbonaceous, silty, contains sub-angular flecks of quartz and mica, irregular hair-line fractures and showing lithological variations along the bedding planes, signifying terrestrial-fluviatile deposits under reducing environment. The values of TOC varies from 1.21 wt.% to 17.32 wt.%, indicating good source rock potentiality. The vitrinite, liptinite, inertinite and mineral matter ranging from 0.28 vol.% to 12.98 vol.%, 0.17 vol.% to 3.23 vol.%, 0.23 vol.% to 9.05 vol.%, and 74.74 vol.% to 99.10 vol.%, respectively. The ternary facies plot of maceral composition substan- tiated that Barakar shales are vitrinite rich and placed in the thermal-dry gas prone region. The low values of the surface area determined following different methods point towards low methane storage capacity, this is because of diagenesis and alterations of potash feldspar responsible for pore blocking effect. The pore size distribution signifying the micro to mesoporous nature, while Type II sorption curve with the H2 type of hysteresis pattern, specifies the heterogeneity in pore structure mainly combined-slit and bottle neck pores.展开更多
The slag melting characteristic of slag forming and slag splashing for 300 t BOF less slag process is researched by combining the methods of the slag chemical composition, the melting point determination and the petro...The slag melting characteristic of slag forming and slag splashing for 300 t BOF less slag process is researched by combining the methods of the slag chemical composition, the melting point determination and the petrographic analysis. The results show that the melting point of final slag for less slag smelting is 20 ~C lower than that for conventional smelting. According to results of the petrographic analysis, the C3S (3CaO ~ SiO2) and C2S (2CaO · SiO2) content for less slag smelting are lower than those for conventional smelting, while the RO (FeO, MgO, MnO, etc) phase and C4AF (4CaO · Al2O3· Fe2O3) phase are higher than those for conventional smelting. According to results of the chemical analysis, the (CaO) content and slag basicity for less slag smelting are higher than those for conventional smelting, while (FeO) and (MgO) content in slag for less slag smelting are almost equal to those for conventional smelting. The reason why slag melting point for less slag smelting is lower than that for con- ventional smelting is that the quantity of added fluorite for less slag smelting is more than that for conventional smel- ting. According tO the analysis results the slag melting point is determined by the C3S, C2S, RO phase and C4AF content. According to the results of slag melting characteristic before and after slag splashing for less slag smelting, the present adjusting slag process has little effect. It is important to adjust the composition of BOF final slag. The (FeO) content in slag is to be reduced at the slag splashing and adjusting slag process for less slag smelting.展开更多
文摘Increasing demand for energy due to the populous Eastern Australia has driven oil and gas industries to find new sources of hydrocarbons as they are the primary energy suppliers.Intensive study has been done on the Volador Formation in the Gippsland Basin by means of core-based petrophysical,sedimentological,and petrographic analyses as well as well log-based interpretation and capillary pressure test.Five wells from Kipper,Basker and Tuna fields with available dataset were investigated in this study:Kipper-1,Basker-1,Basker-2,Basker-5 and Tuna-4.Overall,the formation has good reservoir quality based on the high porosity and permeability values obtained through core and well log petrophysical analyses.The formation made up of mostly moderate to coarse quartz grains that has experienced strong anti-compaction and is poorly cemented.Montmorillonite and illite clays are seen dispersed in the rock formation,with the minority being mixed clays.These clays and diagenetic features including kaolinite cement and quartz overgrowth that can lead to porosity reduction only have insignificant impact on the overall reservoir quality.In addition,capillary pressure data shows that most samples are found in the transition to good reservoir zones(<50%saturation).The results obtained from this study have shown that the Volador Formation in the Gippsland Basin is worth for hydrocarbon exploration.
基金funded by a Natural Science Foundation of Hebei Province(Grant No.D2020403019)the Natural Science Foundation of Hebei Province(Grant Nos.D2020403101 and D2019403041)+2 种基金the Science and Technology Project of Hebei Education Department(Grant No.ZD2020134)the National Natural Science Foundation of China(Grant Nos.41702094 and 41672070)the Science and Technology Innovation Team Project of Hebei GEO University(Grant No.KJCXTD-2021-02)。
文摘To shed light on the genesis of the Dongping deposit and reveal the behaviour of CO_(2),Au and other ore elements(e.g.,Cu,Fe,Zn,As,Sb,Co etc.)in ore-forming fluids,petrographic,microthermometric and synchrotron radiation X-ray fluorescence(SRXRF)analyses of fluid inclusions were conducted.The ore-forming fluid is characterized as an H_(2)O-CO_(2)-NaCl system with medium-high temperatures and low salinity.Four mineralization stages are identified,namely,feldsparquartz(stage 1);pyrite-white quartz(stage 2);sulfide-smoky grey quartz(stage 3);and carbonate-quartz(stage 4).Three types of inclusions were distinguished,based on fluid composition,phase assemblages and mode of homogenization.Type A:H_(2)O-rich fluid inclusions show 2 phases(liquid H_(2)O(LH_(2)O)+vapour H_(2)O(VH_(2)O))at room temperature and homogenize to the liquid phase.Type B:H_(2)O-CO_(2)fluid inclusions contain 2–3 phases(liquid H_(2)O(LH_(2)O)+vapour CO_(2)(VCO_(2));liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2)));liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2))+vapour CO_(2)(VCO_(2)))at room temperature and homogenized to the liquid H_(2)O phase.Type C:H_(2)O-CO_(2)fluid inclusions show 2 phases(liquid H_(2)O(LH_(2)O)+liquid CO_(2)(LCO_(2))at room temperature and homogenize to a critical state.CO_(2)is clearly more enriched in the fluid inclusions of stages 2 and 3 than in stage 1.Stage 1 is dominated by type A(H_(2)O-rich)inclusions with homogenization temperatures(Th)of 220–359℃and salinities of 1.1–3.1 wt%NaCl equivalent.Type B(CO_(2)-rich)inclusions gradually increase in stages 2 and 3.The Th range of type B inclusions in stage 2 is 241–397℃with salinities of 2.2–6.9 wt%NaCl equivalent;the Th range of type A inclusions is 217–373℃with salinities of 1.2–8.1 wt%NaCl equivalent.The Th range of type B inclusions in stage 3 is 215–361℃with salinities of 2.9–6.1 wt%NaCl equivalent;the range of type A inclusions is 158–351℃with a salinity of 0.7–5.5 wt%NaCl equivalent.Stage 4 is characterized by type A with Th of 151–250℃and salinities of 0.9–8.3 wt%NaCl equivalent.The mapping results show that elements As,Te and Sb are more concentrated in vapour CO_(2)than in liquid H_(2)O at room temperature,which suggests that vapour components are more able to transport elements when phase separation occurs.The SRXRF quantitative results show that Au,Cl,S and some other metals are obviously more enriched in the fluid inclusions of stages 2 and 3 than those in stage 1.Additionally,the contents of S in stages 1–3 are much lower than those of Cl,which suggests that gold might migrate mainly in the form of a gold-chloride complex.Au is more enriched in type B fluid inclusions than in type A fluid inclusions,which suggests that the enrichment and migration of gold are closely related to CO_(2)and CO_(2)plays a critical role in the migration and enrichment of gold.The trace elements in the fluid have a similar change trend to those in the Yanshanian syenogranite distributed in the southeastern part of the mining area,which may provide some evidence for an intrusion-related genesis for the Dongping gold deposit.
文摘Zatua Hills are located at Haut Uélé Province of Democratic Republic of Congo (DRC), between northern Bafwasende and southern Paulis (Isiro) Squarred Degrees. Belonging to greenstone belt of Ngayu, that area is identified by the high elevated zone which is remained the witness of stable zone, not affected by the ancienst erosion process. Zatua Hills are in the superior Kibalian formation dated to Neoarchaen, hosted in Upper Congo Granites Massifs of DRC covering a large central zone of NE of DRC, and consisting to dolerite, phyllade, clay rich sediment, poor Banded Iron Formations (BIFs), enriched BIFs, friable hematite, hard hematite, mineralized and unmineralized brechias. Magnetite, martite and hematite are associated to some secondary minerals such as goethite, gibbsite, kaolinite, strengite, variscite and others clay minerals present in BIFs. Petrographic analysis made from the samples collected in situ showed, as well as BIFs and iron ore associated, that magnetite was much abundant oxide mineral which is oxided to martite before to stabilize to hematite during the deposition time. Having about hundred meters of thickness, the rich iron ore of this area content, in the majority less deleterious elements which, are harmful in metallurgic process of iron. These secondary minerals were precipitated at various degrees in the leached cavities of rocks between martite and hematite aggregates to botryoidal texture and, are rich to Al, and are mainly consisting to gibbsite and solid solution series of variscite-strengite (AlPO<sub>4</sub>·2H<sub>2</sub>O and FePO<sub>4</sub>·2H<sub>2</sub>O). Low degree of metamorphism played when magnetite was converted to martite, with the presence of variscite and anatase like witnesses of this event in which, martite was crystalized to hematite.
文摘In the French concept of deep nuclear waste repositories,the galleries should be backfilled with excavated argillite after the site has been filled.Some additives like lime could be used to improve the mechanical characteristics of the argillite.After thousands of years,the degradation of the concrete lining of the galleries will generate an alkaline solution(pH value 12) that will diffuse through the backfill.This study presents the effect of a saturated Ca(OH)_2 solution circulation through lime-treated sample at 60 ℃ for 3,6 and 12 months,respectively.The effect of such circulation on the lime-treated Manois argillite(MA) was assessed by petrographical examination coupled to image analysis and scanning electron microscopy(SEM) equipped with energy dispersive X-ray(EDX) analyser of soil pieces.The objective of this study is to make the link among the mineralogical transformations,the textural and mechanical changes produced in the compacted clayey soil as a consequence of the alkaline solution circulation.
文摘In this paper, we described the petrographical characters of the Mn-bearing rock types outcropping in the Kalakhuta, Ghatia, Gararia, Itala, Wagaicha, Tambesara and Talwara villages of Banswara district. The Mn associated rocks in the study area are phyllite, schist, quartzite and limestone. The mineral assemblage in phyllite formed under greenschist facies metamorphism. Petrographic studies of various phyllite samples also reveal that porphyroblasts of biotite sat in the fine-grained micaceous matrix (Biotite, muscovite, chlorite) along with quartz, opaque and ore minerals. Petrographic studies of schist reveal its formation under prograde metamorphism. Mineral assemblages observed in schist are typical of greenschist to lower amphibolite facies. The various schist samples at places show clusters made up of perfect rhombshaped garnets which suggest the increase in the grade of metamorphism. The quartzites are disposed conformably with the phyllites, and are at times brecciated and re-cemented by secondary chert and manganese. These Mn-bearing quartzites are with sutured/serrated and straight grain boundaries. The quartzite samples are fully composed of quartz showing undulose extinction with subordinate feldspar, micas and carbonatic materials. The petrographic characteristics explain that mostly limestones are the dolomitic composition but some ferruginous varieties are also noticed at places. The purer variety of limestone consists of calcite, dolomite and some magnetite but tremolite, quartz and some minute flakes of biotite also occur in impure variety.
文摘All engineering projects consist of several steps, and one of the main tasks is to identify and characterize the most important features of rock types that will be excavated, crushed, or mined for any particular usage purpose, from a single residential building to major works of infrastructure. Laboratory investigation on engineering geology is thus conducted in order to determine the most relevant rock properties when designing structures such as mining shafts, tunnels, buildings, or reservoir dams to be built in sites associated with rocks. A wide range of laboratory tests is available, making the correct choice of test methods greatly relevant to determine the key property for the planned use of the rock. This paper is an illustrative case of laboratory testing of basaltic rocks to be used as riprap in a reservoir dam. It shows the important role of the petrographic study carried out to analyze the distribution pattern of smectite clay minerals. Test results are explained for the assessment of rock alterability, an essential aspect for the selection of the most suitable basalt variety for the envisaged conditions of use.
文摘In this paper,the strength and petrographic structure of clinker by low-temperature burning are studied. The results show that both the calcining temperature of Ca-CO3 and sintering temperature clinker decreases by 150 degrees C compared with those in traditional rotary kiln,the rate of f-CaO in the clinker sintered at 1300 degrees C is 0.29% similar to 2.81%, the strength of the clinker is 62. 5MPa with maximum 69. 4MPa at a specific area of 2900 similar to 3400cm(2)/g. The results also show that the types of petrographic structure of the clinker can be classified as: homogeneous structure, inlaid or edged structure,stain-melting structure and porous structure. The clinker sintered at 1300 +/- 15 degrees C temperature and with enough retention period is mainly in homogeneous structure.
基金Funded by the State "Key Base Development Foudation" Project("973") of China(201CD610706)Natural Science Foundation of Jiangsu Province,China(2007191SB90098)+1 种基金Analysis and Testing Method Projext of Department of Natural Science Foundation of Jiangsu Provice, China (2006191TS90140)the Scientific Research Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry, China (2006191XLH0132)
文摘To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of China, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^+, K^+, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.
文摘A new method of sintering Ca3SiO5 by the combination of conventional and microwave heating methods was studied. The influence of transitional metal oxides such as Fe2O3, Cr2O3, MnO2, and V2O5 used as the additive of microwave absorption on the microwave-promoted burning of Ca3SiO5 was investigated. The experimental results indicate that the new burning technique is capable of promoting the sintering of Ca3SiO5. At 1200-1300℃ in an electric furnace, Ca3SiO5 can be obtained only when the sample is heated in a microwave for 110-240 s, and the free lime content is below 40wt%. Based on the experiments, Fe2O3, Cr2O3, MnO2, and V2O5 can enhance microwave sintering. Amongst them, Cr2O3 is the most effective. The characteristic of the X-ray diffraction peaks of Ca3SiO5 is similar to those of standard Ca3SiO5, but the peaks are wider.
文摘Studies were taken of ore-bearing rocks, ores and gravity concentrates from Natalka gold deposit by a set of complex methods including mineralogical, petrographic and geochemical research, gravity concentration, and electronic microscopy. The major form of Au found is native: free gold is larger and dispersed, in the form of microinclusions. The obtained results are the basis for an effective technology to extract gold and sequence of profitable mining of Natalka deposit.
文摘Geotechnical studies were carried out on soils from Shango-Chanchaga highway in Minna, in relation to the petrographic characteristics of the parent rock. Samples were obtained from 5 trial pits at 1 km interval for geotechnical analysis. The moisture content varies from 35.0% to 58.5%, liquid limit ranges from 29.0% to 43.0%, plastic limit ranges between 9.0% and 26.5%, while plasticity index ranges from 12.0 to 33.5. The optimum moisture content (OMC) ranges from 12.0 to 14.0, and California Bearing Ratio (CBR) ranges from 2 to 21. The diffractograms showed that the dominant minerals were clinochore (Mg,Fe)6(Si,Al)4O10(OH)8, quartz (SiO2), cordierite (Mg2Al4Si5O18Ar0.625), and albite (Na0.98Ca0.02Al1.02Si2.98O18). The results showed that there exists a relationship between the mineral composition, the texture of the rock, and the geotechnical characteristics of the soil types.
文摘This paper presents the results of petrographic study of sedimentary iron ore from surface strata of the Shendi-Atbara Basin,River Nile State,Sudan.The aims of this study are to investigate the geological behavior and geological conditions affecting precipitation of sedimentary iron ore.The methodologies have been used to realize the objectives of this study include field work,office work and laboratory work including thin sections and polished sections analysis.According to field observation sedimentary iron ore can broadly be considered as occurring in three major classes:Ferribands iron,ferricrete iron and oolitic iron ores.The modes of occurrence of iron ore were described at the outcrops and vertical sedimentary profiles revealed that the iron occurred in the study area at different types in stratigraphic sequence such as cap,bedded and interbedded conformable with Shendi Formation.Petrographic study of iron ore in collected samples using polarized microscope and ore microscope includes study of the textures and structures of ores to obtain ore history.The main types of textures and structures in studied samples are oolitic,granular,lamellar and bands.According to these results the origin of iron ore is formed by chemical precipitation during chemical weathering of surrounding areas in continental lacustrine environment.The iron ore in study area is potential for future mining works and steel industry.
文摘Most of the hinterland of the North China platform is devoid of Late Ordovician strata. The BaiyanhuaMountain section at Shetai Town is a standard section of the Upper Ordovician newly established in recentyears at the northernmost margin of the platform. This establishment directly involved the determination of thenorth boundary of the platform and the understanding of its evolutionary Listory. The area is quite differentfrom the binterland of the platform in Middle Ordovician rock types and sedimentary environments, with theformer characterized by frequent slope deposits and the latter consisting almost entirely of platform deposits.The present paper focuses on the petrographic features and sedimentary ervironments of the Middle-UpperOrdovician strata in the area, providing further theoretical support to the establishment of the section and fil-ling the gap in this respect.
文摘The Bethampudi layered anorthosite complex at the border zone of Archaean supracrustal rocks of Khammam district, Eastern Ghats shows normal stratification predominantly in the form of rhythmic layering and often exhibits of zebra layering. Graded bedding and cumulate structures are also noticed. The rocks of the study area are classified based on petrography into anorthositic rocks, gabbroic rocks and ultramafic rocks and amphibolites. The field relations and major element composition suggest that these anorthosite rocks are of calc-alkaline in nature and petrogenitically related to the gabbroic rocks by the fractional crystallization at ℃.
文摘The geology of the Zango-Daji area was investigated petrographically and geochemically to determine the study area’s rock types and mineralization potential.The study area is underlain by rocks of the basement complex characterized by hilly and undulating rocks,which include granitic gneiss,migmatite gneiss,biotite hornblende granite gneiss,and pegmatites.Observation from the field shows that the study area is dominantly underlain by granitic gneiss.The granitic gneiss is dark grey,medium-coarse-grained,and characterized by weak foliation defined by the alignment of a streak of light and dark coloured minerals.They are widespread in the area constituting about 70%of rock types found in the study area.The average modal percentage of minerals in the rocks from petrographic studies shows that granitic gneiss had quartz 45%,plagioclase 10%,microcline 20%,hornblende 2%,biotite 10%,muscovite 5%,kyanite 8%and other minerals 5%.Also,the pegmatite of the study area has no evidence of mineralization;it contains minerals like quartz,feldspars(microcline and orthoclase),and micas(mostly muscovite).Geochemical analysis of the granitic gneiss of the study area shows that silica is by far the most abundant with a value of 53.5%,Na_(2)O value of 32.5%,Al_(2)O_(3),and k_(2)O of 6.1%and 4.0%,respectively.CaO value of 2.630%accounts for plagioclase feldspar in the granitic gneiss.The QAP diagram was used to determine the petrogenesis of the granitic gneiss.The plot shows the parent rock was a monzogranite with a low percentage of plagioclase in a thin section with a high percentage of quartz and alkali feldspar.The pegmatites of the study area are barren,as confirmed by the XRD result.
文摘The characterization of carbonated rocks of Mintom allowed identifying three features (massive limestone, banded limestone and dolomite). Samples taken in these features were subjected to the physico-chemical analyses and to the mechanical tests. The results obtained show a convergence in the mineralogical composition in particular in the calcareous features (smectite, micas and calcite);the dolomite feature being mainly constituted by dolomite associated with the smectite. The chemical composition allows finding contents raised in CaO, in all the samples. However, in the dolomite and the banded limestone, the concentrations in MgO and in SiO<sub>2</sub> are also important. The mechanical properties showed a good compression resistance for the massive limestone and the dolomite, the mechanical behavior of the banded limestone being low. The exploitation of these results allows recommending carbonated rocks of Mintom in the production of the clinker, agricultural amendments and in the constructions of the civil engineering.
文摘Petrographic, physical, and mechanical assessment investigation of NikanaiGhar limestone aggregate exposed in the Lower Dir area of Malakand Division, Pakistan, were conducted to evaluate and investigate its potential for use as a construction material for engineering projects. Different geotechnical tests and petrographic analyses were performed to evaluate its potential for construction purposes. Geotechnical tests include unconfined compressive strength, ultimate tensile strength test, specific gravity, share strength, porosity, and water absorption. The evaluated physical attributes were compared to standard specifications to determine their suitability as a construction material. Petrographic investigation indicates mainly two types of stones. Stylolitic spar stone and Spar stone are metamorphosed equivalent limestones and are not prone to alkali-silica reactivity. Mutual relationships between physical parameters have been described by simple regression analysis. Significant direct correlation of specific gravity with ultimate tensile strength and uniaxial compressive strength was noted. However, negative trends of Porosity with ultimate tensile strength and uniaxial compressive strength were observed which is in accordance with standard. The analysis revealed that the limestones of NikanaiGhar Formation fall within the standard specification limits and can be used as aggregates for the indigenous construction industry.
基金the National Natural Science Foundation of China(grant No:41390451).
文摘The sand intervals of the Early Cretaceous Lower Goru Formation are a conventional reservoir,generally distributed in the Middle and Lower Indus Basin of Pakistan.Lithostratigraphically formation is classified into two parts;the upper parts are predominantly composed of shale,siltstone,and thin layers of alternate shale and sandstone,while the lower parts are composed of sandstone with interlayering of shale and limestone.The sandstone of the Lower Goru Formation has been further divided into A,B,C,and D sand intervals based on reservoir quality.Detailed depositional facies and reservoir characteristics are essential for the evaluation of hydrocarbon exploration and development.This paper aims to evaluate the depositional environment and reservoir characterization of the siliciclastic reservoir of the Early Cretaceous Lower Goru Formation by integrating the gamma-ray log patterns and petrographic analysis and scanning electron microscopic(SEM)analysis.Petrographic characterization of the sand intervals and Gamma-ray log signatures were used for the interpretation of the depositional environment of the reservoir intervals.Petrographic analysis reveals that the sandstone of the Lower Goru Formation is fine-to medium-grained,well-sorted,arkose or feldspathic arenite.Primary intergranular macroporosity,secondary intragranular macropores,and Intercrystalline micropores were identified within the sandstone by the SEM analysis.The diagenetic analysis suggests that the sandstone possesses high porosity,low permeability,and has undergone significant alterations such as compaction,quartz cementation,feldspar dissolution,and clay minerals alteration.Five electrofacies are interpreted based on gamma-ray log patterns including(1)funnel shape(FA);(2)bell shape(FB);(3)cylindrical shape(FC);(4)bow shape(FD);and(5)serrated shape(FE)patterns.The interpreted facies results reveal shoreface environment for A-sand,Tidal flat for B-sand,mixed tidal flat for C sand,Tide dominated mixed for D-sand,and transgressive shelf for Esand.The present study will be helpful for the assessment of the reservoir quality of the Early Cretaceous Lower Goru Formation for further exploration and development in the Indus Basin of Pakistan.
基金Ministry of Coal for funding support of the project entitled "Shale gas potentiality eva luation of Damodar Basin of India" (Coal S & T grant: CE(Eo I)/30) under the research work has been carried out
文摘The shale deposits of Damodar Valley have received great attention since preliminary studies indicate their potential for shale gas. However, fundamental information allied to shale gas re- servoir characteristics are still rare in India, as exploration is in the primary stage. In this study, Ba- rakar shale beds of eastern part of Jharia Basin are evaluated for gas reservoir characteristics. It is evident that Barakar shales are carbonaceous, silty, contains sub-angular flecks of quartz and mica, irregular hair-line fractures and showing lithological variations along the bedding planes, signifying terrestrial-fluviatile deposits under reducing environment. The values of TOC varies from 1.21 wt.% to 17.32 wt.%, indicating good source rock potentiality. The vitrinite, liptinite, inertinite and mineral matter ranging from 0.28 vol.% to 12.98 vol.%, 0.17 vol.% to 3.23 vol.%, 0.23 vol.% to 9.05 vol.%, and 74.74 vol.% to 99.10 vol.%, respectively. The ternary facies plot of maceral composition substan- tiated that Barakar shales are vitrinite rich and placed in the thermal-dry gas prone region. The low values of the surface area determined following different methods point towards low methane storage capacity, this is because of diagenesis and alterations of potash feldspar responsible for pore blocking effect. The pore size distribution signifying the micro to mesoporous nature, while Type II sorption curve with the H2 type of hysteresis pattern, specifies the heterogeneity in pore structure mainly combined-slit and bottle neck pores.
基金Item Sponsored by National Science and Technology Support Program for 11th Five-Year Plan of China(2006BAE03A00)
文摘The slag melting characteristic of slag forming and slag splashing for 300 t BOF less slag process is researched by combining the methods of the slag chemical composition, the melting point determination and the petrographic analysis. The results show that the melting point of final slag for less slag smelting is 20 ~C lower than that for conventional smelting. According to results of the petrographic analysis, the C3S (3CaO ~ SiO2) and C2S (2CaO · SiO2) content for less slag smelting are lower than those for conventional smelting, while the RO (FeO, MgO, MnO, etc) phase and C4AF (4CaO · Al2O3· Fe2O3) phase are higher than those for conventional smelting. According to results of the chemical analysis, the (CaO) content and slag basicity for less slag smelting are higher than those for conventional smelting, while (FeO) and (MgO) content in slag for less slag smelting are almost equal to those for conventional smelting. The reason why slag melting point for less slag smelting is lower than that for con- ventional smelting is that the quantity of added fluorite for less slag smelting is more than that for conventional smel- ting. According tO the analysis results the slag melting point is determined by the C3S, C2S, RO phase and C4AF content. According to the results of slag melting characteristic before and after slag splashing for less slag smelting, the present adjusting slag process has little effect. It is important to adjust the composition of BOF final slag. The (FeO) content in slag is to be reduced at the slag splashing and adjusting slag process for less slag smelting.