• 제목/요약/키워드: OLISA

검색결과 4건 처리시간 0.016초

Treatment of produced water in a floating carrier bioreactor

  • Ezechi, Ezerie Henry;Sapari, Nasiman;Menyechi, Ezerie Jane;Ude, Clement M.;Olisa, Emmanuel
    • Environmental Engineering Research
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    • 제22권2호
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    • pp.210-215
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    • 2017
  • Produced water is the largest wastestream of oil and gas exploration. It consists of various organic and inorganic compounds that hinder its beneficial use. This study compared the treatment of produced water in a batch suspended and biofilm activated sludge process. The biofilm carrier material was made from Gardenia Carinata shell. COD, $NH_4{^+}-N$ and $NO_3-N$ removal was monitored in both the suspended (control) and floating carrier bioreactors. The results show a rapid reduction of produced water constituents in the floating carrier bioreactor. COD, $NH_4{^+}-N$ and $NO_3-N$ removal was in the range of 99%, 98% and 97% for the floating carrier bioreactor whereas it was 88%, 84% and 83% for the control bioreactor. The rapid reduction of COD, $NH_4{^+}-N$ and $NO_3-N$ clearly indicate that the floating carrier materials served as an attached growth medium for microorganisms, improved the breakdown of produced water constituents and reduced inhibition of microbial metabolic activities.

Geochemistry and Petrogenesis of Pan-african Granitoids in Kaiama, North Central, Nigeria

  • Aliyu Ohiani Umaru;Olugbenga Okunlola;Umaru Adamu Danbatta;Olusegun G. Olisa
    • 자원환경지질
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    • 제56권3호
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    • pp.259-275
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    • 2023
  • Pan African granitoids of Kaiama is comprised of K-feldspar rich granites, porphyritic granites, and granitic gneiss that are intruded by quartz veins and aplitic veins and dykes which trend NE-SW. In order to establish the geochemical signatures, petrogenesis, and tectonic settings of the lithological units, petrological, petrographical, and geochemical studies was carried out. Petrographic analysis reveals that the granitoids are dominantly composed of quartz, plagioclase feldspar, biotite, and k-feldspar with occasional muscovites, sericite, and opaque minerals that constitute very low proportion. Major, trace, and rare earth elements geochemical data reveal that the rocks have moderate to high silica (SiO2=63-79.7%) and alumina (Al2O3=11.85-16.15) contents that correlate with the abundance of quartz, feldspars, and biotite. The rocks are calc-alkaline, peraluminous (ASI=1.0-<1.2), and S-type granitoids sourced by melting of pre-existing metasedimentary or sedimentary rocks containing Al, Na, and K oxides. They plot dominantly in the WPG and VAG fields suggesting emplacement in a post-collisional tectonic setting. On a multi-element variation diagram, the granitoids show depletion in Ba, K, P, Rb, and Ti while enrichment was observed for Th, U, Nd, Pb and Sm. Their rare-earth elements pattern is characterized by moderate fractionation ((La/Yb)N=0.52-38.24) and pronounced negative Eu-anomaly (Eu/Eu*=0.02-1.22) that points to the preservation of plagioclase from the source magma. Generally, the geochemical features of the granitoids show that they were derived by the partial melting of crustal rocks with some input from greywacke and pelitic materials in a typical post-collisional tectonic setting.

Mineralogy and Geochemistry of Shale Deposits in the Lower Anambra Basin, Nigeria: Implication for Provenance, Tectonic Setting and Depositional Environment

  • Olugbenga Okunlola;Agonsi Udodirim Lydia;Aliyu Ohiani Umaru;Raymond Webrah Kazapoe;Olusegun G. Olisa
    • 자원환경지질
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    • 제56권6호
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    • pp.799-816
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    • 2023
  • Mineralogical and geochemical studies of shales within the Lower Anambra Basin was conducted to unravel the depositional environment, provenance, maturity, paleo-weathering conditions, and tectonic settings. Mineralogical studies conducted using X-ray diffraction analysis revealed that the samples were composed of kaolinite, montmorillonite, chlorite, and illite. KaolinIite is the dominant mineral, constituting approximately 41.5% of the bulk composition, whereas the non-clay minerals are quartz, ilmenite, and sillimanite. Geochemical analysis showed a predominance of SiO2, Al2O3, and Fe2O3 contents of the shale samples with mean values of 52.29%, 14.09%, and 6.15% for Imo Shale (IS); 52.31%, 16.70%, and 7.39% for Mamu Shale (MS); 43.21%, 21.33%, and 10.36% for Enugu Shale (ES); 53.35%, 15.64%, and 7.17% for Nkporo Shale (NS); and 51.24%, 17.25%, and 7.78% for Agwu Shale (AS). However, the shales were depleted in Na2O, MgO, K2O, MnO, TiO2, CaO, and P2O5. The trace element ratios of Ni/Co and Cu/Zn of the shale suggest an oxic depositional environment. The average SiO2 vs. Al2O3 ratio of the shales indicated textural maturity. Compared to the PAAS standard, the shales plot below the PAAS value of 0.85, suggesting a high degree of maturity and intensive chemical weathering, further confirmed on a CIA vs. PIA plot. On log (K2O/Na2O) against SiO2 and tectonic setting discriminant function diagrams, the shales plot mostly in the field of passive continental margin tectonic setting. The discriminant function diagrams as well as Al2O3/TiO2 ratio of the shales showed that they were derived from a mixed source (mafic and intermediate igneous rocks).