Treatment of Petroleum Drill Cuttings Using Stabilization/Solidification Method by Cement and Modified Clay Mixes

High organic content in petroleum drill cuttings is a substantial obstacle which hinders cement hydration and subsequently decreases the clean-up efficiency of the stabilization/solidification (S/S) process. In this study, a modified clayey soil (montmorillonite with low to moderate polarity) was used as an additive to cement. Because of its high adsorption capacity, the clay is capable of mitigating the destructive role of organic materials and preventing their interference with the hydration process. Mixes containing different ratios of cement, waste and modified clay were prepared and tested for their mechanical and chemical characteristics. Total petroleum hydrocarbons (TPH) and Pb content of the samples were analyzed as well. For this purpose, the mixes were subjected to unconfined compressive strength (UCS) and toxicity characteristic leaching procedure (TCLP) tests. The results indicated that the specimens with 28-day curing time at a cement/waste ratio of 25% or higher (w/w) and 10% modified clay (w/w) met the Environmental Protection Agency (EPA) criterion for compressive strength. Moreover, a reduction of 94% in the leaching of TPH was observed with the specimens undergoing the TCLP with a cement/waste ratio of 30% (w/w) and a clay/waste ratio of 30% (w/w). Finally, the specimens with 30% cement/waste and 10% clay/waste ratios showed the least concentration (6.14%) of leached Pb

Geological and fluid inclusion studies in the Muteh gold district, Sanandaj-Sirjan zone, Isfahan Province, Iran

Metamorphic rocks of the Sanandaj-Sirjan zone host the Muteh gold mining district. The gold occurrences are in northwest-striking and northeast-dipping normal faults crosscutting the regional ductile pattern of the host rocks. This faulting is possibly related to a Tertiary extensional uplift event. The hydrothermal alteration assemblage quartz-muscovite-pyrite-carbonate-albite overprints the metamorphic assemblage. Gold is associated with pyrite.Fluid inclusion data suggest that gold deposition is related to mixing between a regional C0₂-bearing saline fluid and a dilute fluid, possibly of meteoric origin

Eocene Gold Ore Formation at Muteh, Sanandaj-Sirjan Tectonic Zone, Western Iran: A Result of Late-Stage Extension and Exhumation of Metamorphic Basement Rocks within the Zagros Orogen

A multidisciplinary study including field geology, microstructure analysis, 40Ar/39Ar dating, and fluid inclusion microthermometry and Raman spectrometry has been carried out on the Muteh gold deposit located in a greenschist to amphibolite facies metamorphic rock complex of the Sanandaj-Sirjan tectonic zone, Zagros orogen, Iran. The Muteh gold deposit has been previously interpreted as genetically related to Precambrian granitic intrusions, as an exhalative hot-spring deposit related to Paleozoic rhyolitic-acidic tuffs, and to local metamorphic processes. Host rocks of the gold deposit are predominantly schist and gneiss, and subsidiary amphibolite and quartzite, and are intruded by leucogranites. In the vicinity of the gold deposit, the metamorphic and granitic rocks display a subhorizontal mylonitic foliation, containing a northeast-oriented stretching lineation. Field investigations in one of the producing open pits show that the gold orebodies are controlled by northwest-oriented normal faults and joints, dipping to the northeast and the southwest, and crosscutting the ductile fabric of the host rocks. Both the ductile fabric of the host rocks and the gold ore-controlling brittle structures are interpreted to have formed within a single, continuous extensional event, which started with ductile deformation and gradually changed into brittle deformation. Hydrothermal alteration associated with ore formation consists of quartz, muscovite, pyrite, dolomite-ankerite, and albite, which crosscuts the ductile fabric and overprints the metamorphic minerals of the host rocks. Pyrite is the dominant opaque mineral and is the major phase associated with gold. Chalcopyrite, marcasite, bismuth, galena, sphalerite, and pyrrhotite are subsidiary to rare phases. 40Ar/39Ar incremental-heating and in situ laser-ablation age data reveal a coherent sequence of cooling and hydrothermal events in the metamorphic complex hosting the Muteh gold deposit. Muscovite samples from the alteration zone and from one quartz vein from the orebodies yield 40Ar/39Ar ages between 55.7 and 38.5 Ma and show that gold mineralization is the youngest among the different dated events. This Eocene age is consistent with the young structural setting of the gold orebodies revealing an emplacement along northwestoriented normal faults, which can be correlated with Tertiary extensional tectonic events reported by previous field investigations. The data also indicate that gold ore formation is coeval with magmatism in the adjacent Tertiary Urumieh-Dokhtar magmatic belt and with intrusive activity within the Sanandaj-Sirjan zone, with a 40Ar/39Ar age of 54 Ma near Muteh according to our study. The remaining 40Ar/39Ar data reveal a Cretaceous to early Tertiary metamorphic, magmatic, and deformation history of the complex hosting the Muteh gold deposit. The fluid inclusion study showed that distinct fluids were present during the regional geologic evolution predating ore formation and later Eocene gold ore formation. Early regional fluids consist of an H2O-CO2-NaCl fluid with subsidiary N2 and CH4 that underwent local unmixing. The salinities of the liquid-rich inclusions resulting from unmixing range between 2.2 and 17.5 wt percent NaCl equiv, and those of the CO2-rich, vaporrich inclusions range between 2.8 and 7.2 wt percent NaCl equiv. The high salinity of the regional liquid-rich fluids is attributed to metamorphism of evaporite-bearing sedimentary rocks, magmatic intrusions, retrograde hydration reactions, metamorphism of impure marbles, and migmatization. The fluid inclusions spatially associated with the gold veins postdating regional metamorphism and ductile deformation of the host rocks contain a low-salinity aqueous fluid with a dilute, low-density CO2 component, and maximum salinities between 2.6 and 5.8 wt percent NaCl equiv. Gold deposition at Muteh occurred during or after late stages of Eocene brittle extension as a result of exhumation of the host metamorphic complex, possibly during magmatic activity in the Sanandaj-Sirjam zone. It is most likely linked to the introduction of a distinct low-salinity, low CO2 content aqueous fluid during crustal extension. These fluids are younger than, and therefore unrelated to, the highly saline and CO2-rich, regional metamorphic-magmatic fluids. Our results refute previous models advocating Precambrian to Paleozoic ages of the Muteh gold deposit

Research on wear resistance and friction coefficient of gas-thermal composite coatings with the addition of nano carbon components without lubricants

Сокоров И. О.; Ванюк Э. А.; Zadeh E. Ghazban; Куис Д. В.; Леванцевич М. А.; Лобко Д. Н. Исследование на износостойкость и коэффициент трения газотермических композиционных покрытий с добавкой наноуглеродных компонентов без смазочных включенийВ статье приведены научные исследования на износостойкость и коэффициент трения газотермических композиционных покрытий с добавкой наноуглеродных компонентов без смазочных включений. Установлено, что введение самофлюсующихся порошков с их последующим оплавлением снизило пористость покрытия в 2-3 раза, а коэффициент трения у композиции ПГ- 19М-01 с добавкой наноуглерода уменьшился до 50,8% по сравнению с этой же композицией без наноуглерода

Association of trace metals with various sedimentary phases in dam reservoirs

In the present study sediment and water samples collected from Kowsar Dam reservoir in Kohkiluye and Boyerahmad Province, southwest of Iran, are subjected to bulk digestion and chemical partitioning. The concentrations of nickel, lead, zinc, copper, cobalt, cadmium, manganese and iron in water and bed sediment were determined by atomic absorption spectrometry. The concentrations of metals bounded to five sedimentary phases were estimated. On this basis, the proportions of natural and anthropogenic elements were calculated.The anthropogenic portion of elements are as follows: zinc (96%)> cobalt (88%)> iron (78%)> magnesium (78%)> nickel (78%)> copper (66%)> lead (63 )> cadmium (59%). The results show sediment contamination by nickel, cadmium and lead, according to the world aquatic sediments and mean earth crust values. Manganese and copper have strong association with organic matter and are of high portion of sulfide bounded ions. Finally, The degree of sediment contamination was evaluated using enrichment factor, geo-accumulation index (Igeo) and pollution index (IPoll). The sediments were identified to be of high cadmium and lead pollution index. The pattern of pollution intensity according to enrichment factor is as follows; manganese (1.25) < copper (1.63) < zinc (1.93) < cobalt (2.35) < nickel (3.83) < lead (12.63) < cadmium (78.32). Cluster analysis was performed in order to assess heavy metal interactions between water and sediment. Accordingly, nickel, cadmium and copper are earth originated. Zinc, copper and manganese are dominated by pH. All the elemental concentrations in water and sediment are correlated except for sedimental copper

Research of Thermal Coatings of Composite Materials

Разработаны композиционные материалы на основе абразивостойких, антифрикционных и термореактивных порошков, которые образуют композитное антифрикционное покрытие, обеспечивающее необходимый уровень физико-механических свойств и эксплуатационных характеристик (износостойкость, пористость и прочность сцепления)