Bioremediation System and Methods

Abstract

Algae-based bioremediation systems and methods in which algae is grown in a photobioreactor with nutrients supplied from a nutrient system. An effluent stream in need of remediation is ported to a pond or lagoon and the lagoon is inoculated repetitively with algae grown in the photobioreactor. In an embodiment, a first stage comprises an anaerobic digester which generates combustible gas that can be burned to generate at least a portion of the gas and electricity needed to operate some or all of the nutrient system, the photobioreactor and the lagoon or pond. In some embodiments, the pond or lagoon is multiphasic, and comprises anaerobic and aerobic remediation zones.

1 . A bioremediation system comprising
 a photobioreactor for supplying selected strains of algae,   a nutrient system for supplying sufficient growth medium to the photobioreactor to enable continuous growth of the selected strains of algae,   a multiphasic remediation lagoon or pond adapted to receive organic waste for remediation and also to receive, from the photobioreactor, inoculations of the selected strains of algae.   
     
     
         2 . The bioremediation system of  claim 1  wherein the multiphasic pond comprises at least an anaerobic zone and an aerobic zone, and means for creating substantially consistent directional fluid flow within the pond. 
     
     
         3 . The bioremediation system of  claim 1  wherein the substantially consistent directional fluid flow is created by a paddlewheel. 
     
     
         4 . The bioremediation system of  claim 1  further comprising a feedback loop for adjust the amounts of algae provided by a subsequent inoculation. 
     
     
         5 . The bioremediation system of  claim 1  wherein the nutrient system comprises a control system for metering the supply of selected nutrients to facilitate algae growth in the photobioreactor. 
     
     
         6 . A method for remediating waste streams comprising
 providing an anaerobic digester region for performing a first remediation step, the anaerobic digester generating combustible gas and an effluent stream,   combusting the gas to generate heat, electricity, and CO 2 ,   supplying a portion of the heat, electricity and CO 2  generated by the combusting step to a photobioreactor,   supplying another portion of the heat, electricity and CO 2  generated by the combusting step to a multiphasic pond,   supplying to the multiphasic pond the effluent stream and dense algae produced by the photobioreactor.   
     
     
         7 . The method of  claim 6  wherein the photobioreactor comprises a plurality of light pipes arranged within a tank for growing algae throughout the volume of the tank.