Loading...

Development of Water-Energy Nexus (Watergy)Model Considering Water Quality Pyramid

Hosseinnejad, Ahmad | 2022

180 Viewed
  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 55398 (46)
  4. University: Sharif University of Technology
  5. Department: Energy Engineering
  6. Advisor(s): Saboohi, Yadollah; Shayegan, Jalal; Zarei, Ghasem
  7. Abstract:
  8. Water-energy nexus approach is any water and energy interaction in a system to provide sustainable usage of resources. Quantitative model of interaction of water and energy in analyzing water-energy nexus is not comprehensive approach for solving all challenges facing this section. Qualitative analysis of water-energy nexus provides optimization and prioritization solutions in water and energy systems from other aspects. In present thesis two quantitative and qualitative aspect of water-energy nexus is considered. Initially, for quantitative modeling, interaction and relation of water and energy (watergy) with six principles to form WatErgy Reference System (WERS) was presented. The innovation of quantitative model, is the endogenous calculation of water and energy demands, by adding an integration layer of water and energy services (watergy services). For quantitative and integrated analysis of the watergy system, a mathematical model of water and energy with the minimum total cost objective function was developed for a greenhouse case study (WEGMA-1). Contrary to previous studies, the WEGMA-1 integrated model provides an optimal combination of technologies and an optimal allocation of water and energy resources based on the watergy optimal point for the policy makers, the investors and the stakeholders. The sensitivity analysis is performed by presenting six scenarios with different boundary conditions, considering reduction of energy subsidies and reduction of fertilizer cost and facing quantity and quality water scarcity (A to F scenarios). This optimal combination of technologies (including drainage recycling, Combined heat and power, Photovoltaic) in different scenarios results in reducing the use of water, electricity, and fertilizer by 18%, 31%, and 25% respectively. In result of quantitative model was be chosen the drainage recycling technology in most of the scenarios.The use of drainage recycling involves a combination of different qualities of water in the system. Recycling is one of the main ways for resource replacement in the future. Although the recycling decrease exergy losses of system, the recycling of all the flows of different quality is not rational. There is a need for a quantitative method to prioritize flows and determine the rational condition of their recycling in the system. In the present study, after quantitative analysis of water-energy nexus has been paid to qualitative analysis in system. For the first time, the function of “saved production exergoeconomic cost from recycling (ΔExC)” compared to open cycle developed as a criterion for analyzing to rationalization recycling from a thermoeconomic viewpoint (considering details and effective parameter on this function including φ ، ϴ، ρ ، Ω). Also, for the first time, water quality pyramid was formed based on the unit exergoeconomic cost index (c) for representing the distinction between water flows in a system and their prioritization. The formation of the quality pyramid of water in the greenhouse shows that the nutrition feed water by the amount of the c index is equal to 1168 at the top of the pyramid and the wastewater with the index 0 is in the bottom of pyramid. The analyses of ∆ExC function shows that 2.77 Gj/yr reduction of the whole system exergy losses by waste recycling reduces the exergy of input water sources by 6.6% and the soluble fertilizer resources by 20%. The unit rose production exergoeconomic cost with a close system is 121.3 $/Gj (equivalent to 0.108 $/Cut Flower), which is 3.5 $/Gj less than the open cycle. The result shows positive sign of ∆ExC and be rationalize to use of recycling process in the greenhouse pilot.
  9. Keywords:
  10. Thermoeconomic Analysis ; Water and Energy Nexus ; Technology Evaluation ; Water Quality Pyramid ; Saved Production Exergoeconomic Cost From Recycling (ΔExC) ; Greenhouse Integrated Model ; Watergy Services

 Digital Object List

 Bookmark

No TOC