Alnouri, Sarah (2022-07). Building a Waste Resource Network for Agricultural Applications in Arid Regions: Applications on Industrial Crops. Master's Thesis.
Thesis
Industrial process infrastructure has been rapidly growing in the world, due to the overflowing consumption of fossil fuel energy. This causes arising demand to control environmental damage that has been induced by these processes. The world has been striving to reach sustainability through countless ways. There is a certain balance that is needed to achieve both a desired and sustainable production. This research introduces a method of optimization that will choose a crop to grow while implementing sustainable reuse of industrial liquid waste. The waste is generated from the industrial wastewater treatment procedure, and it is referred to as biosludge. The chosen crop is to be cultivated through a nonideal environment and each of the several industrial crop options was assessed through a model based on several aspects of their input, cost, profit, and carbon dioxide (CO2) emissions. A mixed integer nonlinear programming (MINLP) model was developed to optimize for the best crop that can be planted given the data required for the operative application of the model. The model was able to deliver several alternatives and solutions to the objective function. The main objective of the MINLP model was to minimize the total cost. The total cost equation entailed the fertilizer supply, irrigation water input, crop disease protection, land area, carbon fixation, and the revenue stemming from selling the crop fibers. Several case study scenarios were solved to demonstrate the model's credibility in assuming working scenarios that utilize the waste material properly. A multi-criteria decision analysis assessed the scenarios by varying different inputs of the model. The case study of GTL biosludge was tested with several industrial crop possibilities, irrigation water possibilities, and biosludge and soil mixture options. Reusing waste products such as biosludge, which has to be treated before using its nutrients, was utilized as a soil enhancer. Those nutrients are fed to the soil simultaneously through the biosludge. Cotton was the best performing crop assuming a production rate of 100 t/y. A profit of $141,000/y is to be expected. The soil + 1.5% biosludge mixture was utilized with an addition of 37.3 t nutrient/y and 2.8 t nutrient/y of N and K fertilizer to the soil. That lead to 319 t CO2/y emitted as a result. Seasonality analysis was performed on cotton in order to replicate the growth cycle more accurately.
