The economic evaluation of establishing a plant for producing biodiesel from edible oil wastes in oil-rich countries: Case study Iran Yan Cao a , Amir Doustgani b, * , Abozar Salehi c , Mohammad Nemati d , Amir Ghasemi c , Omid Koohshekan c a School of Mechatronic Engineering, Xi’an Technological University, Xi’an, 710021, China b Department of Chemical Engineering, College of Engineering, University of Zanjan, Zanjan, Iran c School of Environment, College of Engineering, University of Tehran, Tehran, Iran d Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran article info Article history: Received 12 January 2020 Received in revised form 10 July 2020 Accepted 28 August 2020 Available online 7 September 2020 Keywords: Biodiesel Waste cooking oil Break-even price Two-step supercritical methanol Economic assessment Sensitivity analysis Rate of return abstract In this investigation, three chemical processes for biodiesel production evaluated based on the financial standpoint. Due to its strongness and flexibility in economic evaluations, the COMFAR III software uti- lized for assessing processes. The alkali catalyzed process using virgin vegetable oil (process I), an-acid catalyzed process utilizing waste cooking oil (process II), and two-step supercritical methanol process using waste cooking oil (process III) considered as three deferent chemical processes and financial an- alyzes applied on all processes. The results of financial evaluation revealed that the process II with 2.992 million $, had the lowest manufacturing prices and with 7.541 million $ net present value would be considered as the most attractive proposal for investment. However, concerning total equipment costs of process III (1.141 million $) and its fixed investment prices (2.158 million $), this process selected as the most economically attractive process. In the next step, to evaluate the impacts of increased sales revenue, reduction in fixed assets, and operating costs on net present value, a sensitivity analysis was carried out. Sensitivity evaluation revealed that alteration in operating costs significantly impacts the net present value, and this significant change is more tangible in the process III. © 2020 Elsevier Ltd. All rights reserved. 1. Introduction Today, fossil fuels provide more than 80% of the total energy used in the globe, resulting in their serious contribution to envi- ronmental and health issues [1e3]. Efficiency enhancement of the industrial processes using fossil fuels has drawn researchers’ attention, however, costs of transportation and the necessary infrastructure are comparatively expensive due to the fact the most of the world’s gas resources are concentrated in specific areas [4,5]. Due to the above-mentioned issues, tremendous attempts were made to identify the perfect alternative fuels to overcome the financial and environmental effects of global fossil fuel emissions [6e8]. By comparison, as alternative fossil diesel, biofuels are comparatively simple to generate and also renewable. Biofuels can be competitive in fossil fuels depending on their geographical place, feedstock and crude oil prices [9]. Biodiesel, the long-chain fatty acid monoalkyl ester, is a pro- spective renewable alternative to diesel fuel obtained from non- renewable petroleum [10e12]. Biodiesel is biodegradable and non-toxic because it is derived from pure oils and animal fats [13]. In addition, public health can be improved by the utilization of biodiesel fuel since it can reduce exhaust emissions, and on the other hand dependency of fossil fuel can be mitigated [14]. Biodiesel, as a renewable fuel, has become popularly accepted on the energy market because of its distinctive characteristics, including higher cetane number compared to fossil diesel, avail- ability, high flash point, affirmative energy balance, absence of sulfur, natural grease, and moreover, for its transportation current infrastructure can be utilized [15, 16]. Compared to diesel fuel, biodiesel fuel has few emissions of UHC, CO, and smoke respec- tively about 20%, 30%, and 50% lesser [17 , 18]. Comparing petro- diesel and neat biodiesel (B100), B100 can reduce polycyclic aro- matic hydrocarbons (PAHs) and unburned hydrocarbons about * Corresponding author. E-mail addresses: jantonyz@163.com (Y. Cao), Doustgani@znu.ac.ir (A. Doustgani), amir_ghasemi@ut.ir (A. Ghasemi). Contents lists available at ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy https://doi.org/10.1016/j.energy.2020.118760 0360-5442/© 2020 Elsevier Ltd. All rights reserved. Energy 213 (2020) 118760