Date of Publication


Document Type

Bachelor's Thesis

Degree Name

Bachelor of Science in Chemical Engineering

Subject Categories

Chemical Engineering


Gokongwei College of Engineering


Chemical Engineering

Thesis Advisor

Arnel B. Beltran
Kathleen B. Aviso

Defense Panel Chair

John Frederick D. Tapia

Defense Panel Member

Aileen H. Orbecido
Jerwin Lawrence C. Go


One issue that is commonly found in a fish processing industry is its high consumption of water, as well as the consequent effluents generated. Since water resources are limited, there is a need for proper treatment of wastewater from these industries to reuse them in a different way through the optimization of water usage. This research developed a methodology on synthesizing optimal water networks using P-graph refined by resource conservation networks with material interception schemes. Through the understanding and application of P-Graph algorithms and axioms, a superstructure is constructed that consist of all possible connections within the case study and is run to obtain all combinatorial feasible solution with respect to the objective function. The structural integrity of the solution structures obtained were assessed through Global Sensitivity Analysis (GSA) to see how these structures are sensitive to changes in the system parameters in terms of its flowrate and quality. Two P-Graph superstructures are presented where the first one assumed that the wastewater was treated separately while the other one assumed that the wastewater was mixed and treated as a whole. Moreover, the sensitivity analysis showed which treatment was more beneficial when there are sudden changes in the flow rate at constant quality. Furthermore, the total annual cost (TAC) determined the practicability and feasibility of the two cases. The results of these cases show that the methodology can produce optimal solutions as well as eliminate those solutions that contains uncertainties. Thus, improving the efficiency of the wastewater treatment and minimizing the large consumption of freshwater in the fish processing industry.

Abstract Format






Physical Description

ix, 127 leaves, illustrations (some color)


Fishery processing—Water reuse; Water efficiency; Sewage—Purification; Water reuse

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Available for download on Thursday, September 22, 2022