Optimal Integrated Plant for Production of Biodiesel from Waste

Abstract

In this work, we have optimized an integrated facility for the production of fully renewable biodiesel from waste via anaerobic digestion. On the one hand, the biogas produced is dry reformed to obtain syngas and methanol. On the other hand, the digestate remaining is used as a nutrient to grow algae. Algae oil is transesterified using internally produced methanol. The problem is formulated as a large non-linear programming problem (NLP) to compute the optimal operating conditions of the various reactors as well as the biogas composition and the content of nutrients in the digestate. Optimal heat exchanger and water networks are designed afterward. A total of 3110 kt/yr of manure is processed for the production of 90 Mgal/yr of biodiesel and 46.7 kt/yr of methanol. The process uses a fraction of the biogas to provide the energy required at the reformer, but the process still needs 1.5 MJ/gal of fatty acid methyl ester and 1.22 gal of water per gal of biodiesel. The production cost of biodiesel is competitive with previous work, 0.31 €/gal, but the investment is higher due to the need to process the waste into biogas, 193 M€. A scaled-down study is also carried out to evaluate the production and investment cost as a function of the farm size.

Process Optimization for the Hydrothermal Production of Algae Fuels

“…A surrogate model to predict the effect of these four variables on the algae growth using data from several studies is developed. We first consider the model developed in a previous paper wherein the effect of the nutrients was already considered, eq . This previous model is corrected to include the effect of light and temperature as follows.…”

A Methodology to Evaluate Solvent Extraction-Based Processes Considering Techno-Economic and Environmental Sustainability Criteria for Biorefinery Applications

“…Furthermore, process integration has been explored in an effort to improve the environmental and economic performance of biorefineries. For example, Hernández and Martín proposed an integrated facility that produces algae biodiesel using manure treated via anaerobic digestion (AD). The resulting biogas and digestate are used to produce methanol for the lipid transesterification process and as nutrients to increase algae yield during cultivation, respectively, thus reducing the overall production cost to competitive levels and avoiding the use of fossil-based resources.…”

Ionic Liquid@Amphiphilic Silica Nanoparticles: Novel Catalysts for Converting Waste Cooking Oil to Biodiesel

“…Biodiesel is usually obtained by transesterification reactions assisted by acid, alkali, or enzyme catalysts. , However, conventional homogeneous catalysts (NaOH, H 2 SO 4 , H 3 PO 4 , HCl, etc.) suffer from many shortcomings, such as difficulty in separation, equipment corrosion, and necessitating feedstock oil with high quality, especially when WCO is used as the feedstock. , Although ionic liquids (ILs) with high catalytic activity and chemical stability have been widely studied, − their applications remain very limited because of their high cost and difficulty in recycling.…”

“…9 T h i s c o n t e n t i s Biodiesel is usually obtained by transesterification reactions assisted by acid, alkali, or enzyme catalysts. 10,11 However, conventional homogeneous catalysts (NaOH, H 2 SO 4 , H 3 PO 4 , HCl, etc.) suffer from many shortcomings, such as difficulty in separation, equipment corrosion, and necessitating feedstock oil with high quality, especially when WCO is used as the feedstock.…”