Flash Hydrolysis of Microalgae for On-site Nutrients Recovery and Biofuels Production

EPA Grant Number: SU835501
Title: Flash Hydrolysis of Microalgae for On-site Nutrients Recovery and Biofuels Production
Investigators: Kumar, Sandeep
Current Investigators: Kumar, Sandeep , Drake, Hannah , Garcia Moscoso, Jose Luis , Mfrase-Ewur, Kwamena , Popov, Sergiy , Ricci, Jonathan D , Talbot, Caleb , Teymouri, Ali , Wilson, Paul E
Institution: Old Dominion University
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2013 through August 14, 2014
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2013) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Energy , P3 Challenge Area - Materials & Chemicals , P3 Awards , Sustainability


In view of the rapid development of microalgae as a feedstock for the large scale biofuels production there is an immediate concern of nutrients loss at bio-refineries. Algae contain three major biopolymers that include lipids, carbohydrates, and proteins. Carbohydrates and lipids are precursor to biofuels whereas proteins can cause the loss of nitrogen fertilizer if it is not recovered. Nitrogen and phosphorus are the two primary macronutrients which are supplied using ammonia and/or nitrates as nitrogen source and phosphates as phosphorous source during algae cultivation. The huge demand of water and nutrients (nitrogen and phosphorous) for algae cultivation poses challenges for the sustainable operation. The P3 team proposes to develop a novel flash hydrolysis process for recovering more than 2/3rd of macronutrients (N & P) contained in algal biomass without the use of any chemicals. An on-site flash hydrolysis process will help in recovering and recycling whereas lipids can be used for biofuels production.


Flash hydrolysis is a process to capitalize on the difference in reaction kinetics of algae components and fractionate proteins in liquid phase in a very short residence times (few seconds) by using a continuous flow reactors under subcritical water medium. The aqueous phase recovered after flash hydrolysis is studied for the nutrients recovery/recycling whereas lipid-rich solids are characterized as a feedstock for biofuels production. The approach and activities of the proposed project are focused on accomplishing the (i) optimized process data on protein extraction from microalgae using subcritical water via flash hydrolysis process, and (ii) characterization of aqueous phase for nutrients recovery and recycling to algal pond, and (iii) characterization of lipid-rich solid residue for biofuels production.

Expected Results:

Outcomes are (i) novel reactor design with tunable residence time for flash hydrolysis, (ii) reaction kinetics of proteins hydrolysis in subcritical water medium, (iii) characterization of nitrogen-derived compounds present in algal hydrolyzate, and (iv) characterization of lipid-rich residues for biofuels production.

Publications and Presentations:

Publications have been submitted on this project: View all 5 publications for this project

Supplemental Keywords:

Scenedesmus sp., nutrients, amino acids, algal hydrolyzate;

Progress and Final Reports:

  • Final Report