CORE TECHNOLOGY
HR BioPetroluem’s core technology is a photosynthetic production system that economically grows proprietary algae strains at a commercial-scale. The production system is unique in that it couples closed-culture photobioreactors with open ponds in a two-stage process. Previous attempts at scaling up algae production have used a photobioreactor or open pond individually, not coupled. Open pond production, which is needed for rapid algae growth, has historically been hampered by the contamination by undesirable algae strains. Photobioreactors by themselves are unable to produce algae at an acceptable rate and would take up too much room to become commercially viable.
With the development of this hybrid production system, HR BioPetroleum has achieved significant breakthroughs for the commercialization of algae production.
Our system:
- Combines low cost and the high productivity of algae ponds with the protection of culture-closed photo bioreactors
- Allows contamination-free monocultures of the most productive algae to be cultivated
- Minimizes capital investment as a cost factor
HR BIOPETROLEUM’S TECHNOLOGY PROCESS
STEP 1 – Select Algae Strain
HR BioPetroleum has licensed unique and naturally occurring algae strains from the University of Hawaii that have been selected for high production of algae oil and rapid growth under targeted commercial production conditions.
STEP 2 – Grow Algae in a Photobioreactor
A photobioreactor is used in the first stage of algae production to maintain the constant conditions that favor continuous cell division and prevent contamination of the culture by other organisms.
In our pilot plant, the main body of the production photobioreactor is a long series of four large temperature and pH controlled tubes that are connected together in parallel. The algae are exposed to sunlight while kept in suspension to maximize growth.
STEP 3 – Transfer and Grow Algae in Open Ponds
In the second stage, the algae is transferred from the photobioreactors to an open pond system. The open pond is a paddlewheel-driven, recirculating raceway, fitted with a durable plastic liner.
The goal of the second stage is to expose the cells to nutrient deprivation and other environmental stresses that lead, as rapidly as possible, to synthesis of the product of interest–for biodiesel this is oil. Environmental stresses that stimulate oil production can be applied rapidly by transferring culture from the photobioreactor to an open pond. Ponds, like photobioreactors, are exposed to full sunlight.
In our pilot plant, on the first day of pond operation, photobioreactor culture is transferred at dawn to a full pond of nutrient-depleted culture medium. Only enough nutrients are transferred with the fresh culture to allow cell division to continue through the morning of the second day.. Depending upon the desired product, , the pond is harvested, cleaned and prepared for a new production cycle on the second or third day after inoculation.
STEP 4 -- Harvest Algae
The algae cells are concentrated by gravitation into a slurry, excess water removed, then further concentrated by centrifugation. The wet biomass is then dried.
STEP 5 -- Process Algae
The oil and other by-products are extracted by a proprietary process.
WHY OUR TECHNOLOGIES SUCCEED WHERE OTHERS FAIL
The key to success is to reduce the residence time in open ponds, where cultures are susceptible to contamination. This can be done only by providing a continuous supply of uncontaminated inoculum in large volume, which requires industrial scale photobioreactors. Our results demonstrate that, even when photobioreactor cultures are maintained under light-limited conditions that favor relatively low growth rates, they occupy a minor fraction of the area required for the entire cultivation system. The most rapid growth rates occur in the open ponds, allowing for a very short residence time and thus avoiding contamination in what represents the majority of the cultivation system on an area basis.
The coupled system minimizes cost. In a coupled system, photobioreactors provide a continuous source of single-species culture in ample quantity to inoculate the open ponds, allowing the batch cultures in open ponds to exhaust the nutrient supply in a short time, thus avoiding the perils of contamination by other species.