Eruptive history and volcano-tectonic evolution of Paka volcanic complex in the northern Kenya rift: Insights into the geothermal heat source

Absorption and adsorption chillers applied to air conditioning systemsThis work presents an application possibility of sorption refrigerators driven by low temperature fluid for air conditioning of buildings. Thermodynamic models were formulated and absorption LiBr-water chiller with 10 kW cooling power as well as adsorption chiller with silica gel bed were investigated. Both of them are using water for desorption process with temperatureTdes= 80 °C. Coefficient of performance (COP) for both cooling cycles was analyzed in the same conditions of the driving heat source, cooling waterTc= 25 °C and temperature in evaporatorTevap= 5 °C. In this study, the computer software EES was used to investigate the performance of absorption heat pump system and its behaviour in configuration with geothermal heat source.

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Performance and Cost Optimization of Integrated Absorption Power Cycle and Liquefied Natural Gas for the Sabalan Geothermal Heat Source

Integration of Clean and Sustainable Energy Resources and Storage in Multi-Generation Systems ◽

10.1007/978-3-030-42420-6_8 ◽

2020 ◽

pp. 141-163

Author(s):

Hadi Rostamzadeh ◽

Towhid Parikhani ◽

Hadi Ghaebi

Keyword(s):

Natural Gas ◽

Heat Source ◽

Cost Optimization ◽

Liquefied Natural Gas ◽

Geothermal Heat ◽

Power Cycle ◽

Absorption Power

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Exergoeconomic comparison and optimization of organic Rankine cycle, trilateral Rankine cycle and transcritical carbon dioxide cycle for heat recovery of low-temperature geothermal water

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650919844647 ◽

2019 ◽

Vol 233 (8) ◽

pp. 1068-1084 ◽

Cited By ~ 5

Author(s):

Afsaneh Noroozian ◽

Abbas Naeimi ◽

Mokhtar Bidi ◽

Mohammad Hossein Ahmadi

Keyword(s):

Sensitivity Analysis ◽

Low Temperature ◽

Heat Source ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Working Fluid ◽

Cost Ratio ◽

Exergetic Efficiency ◽

Geothermal Heat ◽

Product Cost

Depleting fossil fuel resources and the horrible environmental impacts due to burning fossil fuels emphasize the importance of using renewable energy resources such as geothermal and solar energies. This paper compares performance of CO2 transcritical cycle, organic Rankine cycle, and trilateral Rankine cycle using a low-temperature geothermal heat source. Thermodynamic analysis, exergetic analysis, economic analysis, and exergoeconomic analysis are applied for each of the aforementioned cycles. In addition, a sensitivity analysis is performed on the system, and the effects of geothermal heat source temperature, evaporator pinch point temperature, and turbine inlet pressure on the cycle's performance are evaluated. Finally, the systems are optimized in order to minimize product cost ratio and maximize exergetic efficiency by using the genetic algorithm. Results indicate that the maximum thermal efficiency is approximately 13.03% which belongs to organic Rankine cycle with R123 as working fluid. CO2 cycle has the maximum exergetic efficiency, equals to 46.13%. The minimum product cost ratio refers to the organic Rankine cycle with R245fa as working fluid. Moreover, sensitivity analysis shows that increasing geothermal heat source temperature results in higher output power, product cost ratio, and exergy destruction ratio in all cycles.

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The effect of a localized geothermal heat source on deep water formation

Nonlinear Processes in Geophysics ◽

10.5194/npg-18-841-2011 ◽

2011 ◽

Vol 18 (6) ◽

pp. 841-847

Author(s):

M. Vincze ◽

A. Várai ◽

E. Barsy ◽

I. M. Jánosi

Keyword(s):

Heat Source ◽

Deep Convection ◽

Surface Boundary ◽

Dimensional Model ◽

Deep Water Formation ◽

Characteristic Parameters ◽

Geothermal Heat ◽

Water Formation ◽

Bottom Heat ◽

Steady State Solutions

Abstract. In a simplified two-dimensional model of a buoyancy-driven overturning circulation, we numerically study the response of the flow to a small localized heat source at the bottom. The flow is driven by differential thermal forcing applied along the top surface boundary. We evaluate the steady state solutions versus the temperature difference between the two ends of the water surface in terms of different characteristic parameters that properly describe the transition from a weak upper-layer convection state to a robust full-depth deep convection. We conclude that a small additional bottom heat flux underneath the "cold" end of the basin is able to initiate full-depth convection even when the surface heat forcing alone is not sufficient to maintain this state.

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Succession of Cainozoic Vertebrate Assemblages from the Northern Kenya Rift Valley

Nature ◽

10.1038/233389a0 ◽

1971 ◽

Vol 233 (5319) ◽

pp. 389-394 ◽

Cited By ~ 61

Author(s):

W. W. BISHOP ◽

G. R. CHAPMAN ◽

A. HILL ◽

J. A. MILLER

Keyword(s):

Rift Valley ◽

Kenya Rift ◽

Northern Kenya ◽

Kenya Rift Valley

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Distribution of gallium between phenocrysts and melt in peralkaline salic volcanic rocks, Kenya Rift Valley

Mineralogical Magazine ◽

10.1180/minmag.2010.074.2.351 ◽

2010 ◽

Vol 74 (2) ◽

pp. 351-363 ◽

Cited By ~ 6

Author(s):

R. Macdonald ◽

N. W. Rogers ◽

B. Bagiński ◽

P. Dzierżanowski

Keyword(s):

Rift Valley ◽

Inductively Coupled Plasma ◽

Magma Mixing ◽

Volcanic Rocks ◽

Alkali Feldspar ◽

Volcanic Complex ◽

Kenya Rift ◽

Inductively Coupled ◽

Plasma Mass Spectrometry ◽

Kenya Rift Valley

AbstractGallium abundances, determined by laser ablation-inductively coupled plasma-mass spectrometry, are presented for phenocrysts and glassy matrices from a metaluminous trachyte and five peralkaline rhyolites from the Greater Olkaria Volcanic Complex, Kenya Rift Valley. Abundances in the glasses range from 28.9 to 33.3 ppm, comparable with peralkaline rhyolites elsewhere. Phenocryst Ga abundances (in ppm) are: sanidine 31.5–45.3; fayalite 0.02–0.22; hedenbergite 3.3–6.3; amphibole 12; biotite 72; ilmenite 0.56–0.72; titanomagnetite 32; chevkinite-(Ce) 364. The mafic phases and chevkinite-(Ce) are enriched in Ga relative to Al, whereas Ga/Al ratios in sanidine are smaller than in coexisting glass. Apparent partition coefficients range from <0.01 in fayalite to 12 in chevkinite-(Ce). Coefficients for hedenbergite, ilmenite and titanomagnetite decrease as melts become peralkaline. The sharp increase in Ga/Al in the more fractionated members of alkaline magmatic suites probably results from alkali feldspar-dominated fractionation. Case studies are presented to show that the Ga/Al ratio may be a sensitive indicator of such petrogenetic processes as magma mixing, interaction of melts with F-rich volatile phases, mineral accumulation and volatile-induced crustal anatexis.

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