A lateral circulator for generating agitation or circulation in a cultivation pond is disclosed. The circulator comprises at least a drive pulley and a secondary pulley, both oriented vertically and placed in the pond separated from one another along the length of the pond. The drive pulley is coupled to a motor, or to a drive train that is itself coupled to the motor. An endless belt is trained over the drive pulley and the secondary pulley. A plurality of cleats is provided along the exterior of the belt. The cleats are typically angled and serve to drive water as the belt rotates through the water. Typically, the belt would extend over much of the length of the cultivation pond, providing agitation and circulation over an extensive, continuous area of the cultivation pond.

In an embodiment of the invention, aqueous growth medium in a pond can be used to grow algae which can be pumped to a primary dewatering device where the algae can be separated from the harvested growth media based on the flow of the harvested growth media and gravity. The flow through the primary de-watering device can be optimized to maintain log phase growth in the pond, while minimizing the pumping cost and maximizing the concentration of total solids in the primary de-watered algae.

The present invention relates to the growth of algae, in particular to processes and systems for preparing and delivering an algal growth medium to one or more algal aquaculture ponds that significantly reduces capital and operating costs relative to known processes and systems, and that provides for a uniform algal growth medium that can be delivered to a plurality of algal aquaculture ponds when a plurality of algal aquaculture ponds is present.

Herein disclosed is a method of processing a medium containing algae microorganisms to produce algal oil and by-products, comprising providing the medium containing algae microorganisms; passing the medium through a rotor-stator high shear device; disintegrating cell walls of and intracellular organelles in the algae microorganisms to release algal oil and by-products; and removing the algae medium from an outlet of the high shear device. In an embodiment, disintegration is enhanced by a penetrating gas capable of permeating the cell wall. In an embodiment, enhancement is accomplished by super-saturation of the penetrating gas in the medium or increased gas pressure in a vessel. In an embodiment, the penetrating gas is different from the gas produced by the cell during respiration. A suitable system is also discussed in this disclosure.

The present invention relates to a method for culturing microalgae, including: (a) immersing a photobioreactor including a culture container through which a culture solution but not microalgae passes into environmental water; and (b) supplying additional environmental water into the culture container. Through the present invention, it is expected that microalgae can be economically and efficiently mass cultured.

A system for growing an algal culture to create a biomass includes a plurality of linearly interconnected, sloped-gradient, gravity-driven, raceway ponds. Surface areas of the ponds are sequentially increased in accordance with a multiplier, with the pond surface area of the last raceway pond in the sequence being as large as fifty acres. For the present invention, a fluid transfer system connects each raceway pond with every other raceway pond in the system. Control over each individual raceway pond is provided to monitor and evaluate algal culture in the pond. Based on this evaluation, the fluid transfer system is activated to provide water, nutrients and other additives to maintain predetermined growth parameters for algae in each of the raceway ponds.

The invention relates to the field of microalgae culture and specifically relates to a trap-type carbon supplement device and carbon supplement method for cultivating microalgae in an open pond. The trap-type carbon supplement device for cultivating microalgae in an open pond, comprises a trap-type container, a partition plate and a gas distributor, wherein the gas distributor is positioned at the culture solution inlet of the trap-type carbon supplement device; the thickness of the trap-type carbon supplement device on the side of the culture solution inlet is 0.5-2 times of the depth of the culture solution in the open pond; the gap between the lower end of the partition plate and the bottom of the trap-type container is 0.5-2 times of the thickness of the trap-type carbon supplement device on the side of the culture solution inlet; the upper end of the partition plate is higher than the wall of the trap-type container; and the width of the partition plate is matched with the trap-type container. The carbon supplement device of the invention can make the gas-liquid contact time longer and reduce the depth of the trap-type container, therefore it can reduce the flow resistance of the liquid in the carbon supplement device and save energy consumption.

A gravity flow photobioreactor core (10) comprised of a support means (3); a tube (5) that continuously runs and curls with declination about a vertical axis to form a stack (7) of levels (9) and having an inlet sparge (11); a gas exchange tank (13) and a central feed pipe (15) with a sparge (17). A gravity flow photobioreactor farm comprised of a bottom tank (19); a pump (21); a plurality of bioreactor cores (10) connected in series at decreasing elevations and a return pipe (23).

A method and apparatus for extracting CO.sub.2 from air comprising an anion exchange material formed in a matrix exposed to a flow of the air, and for delivering that extracted CO.sub.2 to controlled environments. The present invention contemplates the extraction of CO2 from air using conventional extraction methods or by using one of the extraction methods disclosed; e.g., humidity swing or electro dialysis. The present invention also provides delivery of the CO.sub.2 to greenhouses where increased levels of CO.sub.2 will improve conditions for growth. Alternatively, the CO.sub.2 is fed to an algae culture.

Disclosed herein is a system for circulating fluid in an algae cultivation pond. The system includes an algae cultivation pond having an aspect ratio of length to width between 0.7:1 to 2:1, and the pond is at least 5 acres in overall size. An island has a first side and a second side and is positioned in the pond to create a first channel adjacent the first side of the island and a second channel adjacent the second side of the island. An energy input means is located in the first channel and moves fluid around the island through the first channel and through the second channel. The second channel is at least three times wider than the first channel, and a length of the island is at least six times larger than a width of the island.