Analysis, economical and technical enhancement of an organic Rankine cycle recovering waste heat from an exhaust gas stream

Abstract

Any effort with the aim of increasing the total electrical power generation (EPG) due to the existed constraints in vessels is desired in power plants. Using Organic Rankine Cycle (ORC) for recovering waste heat of an exhausting gas is considered as an auxiliary way for improving EPG value. In this study, four ORC arrangements were first modeled for six refrigerants by EES software and the first and second laws of thermodynamics efficiency (ηI and ηII, respectively) and mass flow rate were studied for these cycles. Based on modeling results, the best arrangement was selected for each refrigerant such as; F‐type (Reference cycle+ Intermediate recuperator+ Final recuperator) for R123, H‐type (Reference cycle+ Intermediate recuperator) for R114 and n‐butane and R‐type (Reference cycle + Final recuperator) for n‐pentane, n‐heptane, and toluene. The ηI value as a technical objective function was then optimized for the above cycles by Aspen HYSYS. n‐heptane and toluene cycles were chosen due to higher first‐law efficiency value and then were studied under different source temperature condition and n‐heptane cycle showed better adaptability. Afterward, exergoeconomic was applied on n‐heptane cycle and maximum cycle pressure was chosen as a design variable for economically optimizing net final income (NFI). Finally, NFI value is increased from 423.1$/kW·h to 609.9$/kW·h about 44.2%, while the second‐law efficiency value is just decreased from 25.6% to 20.6% about 5%.

Exergoeconomic analysis for crude oil gathering and transportation system in matrix pattern

“…[13][14][15] In this paper, a gathering and transportation system is analyzed combined with exergoeconomics. [13][14][15] In this paper, a gathering and transportation system is analyzed combined with exergoeconomics.…”

“…Most of the previous studies on gathering and transportation system were from the perspective of energy analysis and exergy analysis, in which only energy saving was considered rather than cost saving. [13][14][15] In this paper, a gathering and transportation system is analyzed combined with exergoeconomics. Not only energy saving is considered, but also the saving of cost investment analysis is taken into consideration, which is also an innovation in the gathering and transportation system.…”

Exergy and economic assessments of an organic rankine cycle module designed for heat recovery in commercial truck engines

“…The ORC cost estimation for sub-systems are realized from the following expressions: -C Sys = C HX, eva + C HX, con + C tur + C p (2.10) Cost of working fluid, (21) C w f = 10C rate (2.11) Cost of piping (22) C pipe = 0.051C Sys (2.12) Annual operation and maintenance cost, (23) C O&M = 0.02C Sys (2.13) Total cost of the ORC system elements…”

Thermoeconomic Modelling and Parametric Study of a Simple ORC for the Recovery of Waste Heat in a 2 MW Gas Engine under Different Working Fluids

“…To estimate the total production cost (TPC) of the WHR systems, the total capital invested (TCI) and the operation and maintenance costs (O&M) are considered, as shown in Equation (6) [50].…”