A continuous method for growing a specific strain or species of micro algae, the method adapted to operate under positive pressure causing internal high turbulence, which reduces contaminant intrusion, the method also being capable of providing growing conditions for microalgae and recycling unused reactants and process water in a growth system, the method comprising the steps of:
- a) providing the specific strain or species of micro algae;
- b) providing a central distribution tank adapted to act as a central process control location for the growth system where all process variables are monitored and data is sent to a central computer system which maintains the growing conditions;
- c) introducing the specific strain or species of microalgae into the central distribution tank;
- d) providing a plurality of microalgae growing modules, adapted to function in a true mixotrophic manner allowing full 24/7 growth cycles and an attendant high growth rate, wherein the microalgae growing modules are made of a material comprising a polyurethane polymer which is resistant to ultraviolet degradation from sunlight and which can be fabricated in lengths exceeding 200 meters without the need for connectors and having reduced biofilm buildup due to the internal high turbulences, which scour the interior surfaces;
- e) providing a source of pressurized CO2, connected to the a central distribution tank for pressurizing the CO2 supply, wherein the CO2 supply is introduced at a pressure sufficient to cause a turbulent flow within the growth system;
- f) repairing and installing additional units while the growth system is growing algae, wherein the microalgae growing modules have a diameter sufficient to provide required tensile strength, specific volume and sunlight transmission;
- g) providing an inline dewatering system which allows algae harvesting while the growing system is functioning thereby maintaining algae growing concentrations during the growth cycle;
- h) recovering and utilizing unused reactants and process water, wherein such unused reactant and process water are reconditioned to defined specification prior to reuse;
- i) adjusting the temperature of the material in the algae growing modules, wherein the growing modules comprise growth medium, wherein the growing modules are connected to the central distribution tank via transfer lines, and wherein the temperature adjustment, either hotter or colder, is done using a liquid material not toxic to the growing algae but which never actually is in physical contact with it, the required heat transfer being accomplished via a tank jacket on the central distribution tank or external heat exchanger placed in the growth medium transfer lines;
- j) providing a physically smooth internal construction within the growth system having minimal locations for material to lodge, thereby permitting the use of Clean In Place technology to thereby allow system cleaning and purification to be accomplished without system disassembly and reassembly;
- k) providing support systems that can add required micronutrients, food for the algae, or other materials required for optimal algae growth, wherein the required micro-nutrients are added to the central distribution tank;
- l) maintaining the specific strain or species of microalgae in the growth system and exposing same to a light source or source of sugar for sufficient time for growth of the algae to reach about 0.5 grams of biomass per liter of water or media;
- (m) removing the biomass from the growth system and removing excess water or medium from the biomass by moving the biomass through a filtration system, thereby providing the pure specific strain or species of micro algae, and
- (n) cleaning the growth system by introducing a cleaning solution into the central distribution tank without disassembly and reassembly of the growth system to provide a clean growth system for reinoculating the growth system with the previous algae or for introducing a different algae species and repeating steps (a) to (m).