ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION (2002)

This quarterly report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 10/3/2001 through 1/02/2002. Most of the achievements are milestones in our efforts to complete the tasks and subtasks that constitute the project objectives. Our research team has made significant progress towards completion of our Phase I objectives, and our current efforts remain focused on fulfilling these research objectives in accordance with the project timeline. Overall, we believe that we are on schedule to complete Phase I activities by 10/2002, which is the milestone date from the original project timeline. Specific results and accomplishments for the fourth quarter of 2001 include: (1) New procedures and protocols have been developed to increase the chances of successful implementation in the bioreactor of organisms that perform well in the lab. The new procedures include pre-screening of organisms for adhesion characteristics and a focus on identifying the organisms with maximum growth rate potential. (2) Preliminary results show an increase in adhesion to glass and a decrease in overall growth rates when using growth media prepared with tap water rather than distilled water. (3) Several of the organisms collected from Yellowstone National Park using the new procedures are currently being cultured in preparation for bioreactor tests. (4) One important result from a test of growth surface temperature distribution as a function of gas stream and drip-fluid temperatures showed a high dependence of membrane temperature on fluid temperature, with gas stream temperature having minimal effect. This result indicates that bioreactor growth surface temperatures can be controlled using fluid delivery temperature. The possible implications for implementation of the bioreactor concept are encouraging, since it may be possible to use the bioreactor with very high gas stream temperatures by controlling the temperature of the organisms with the fluid temperature. (5) Investigation of growth surface materials continues, with Omnisil and Scotch Brite emerging as the leading candidates. More investigation of these and other material types is still needed to determine the best material for particular combinations of organisms and harvesting methods. (6) Tests of harvesting methods and harvesting system designs have shown that desirable levels of ''percentage algae removal'' can be achieved for particular organisms and growth surface materials, for example Cyanidium on polyester felt. Additional testing continues to better characterize sensitivity of the ''percentage removal'' to various system design parameters, but these tests have been delayed due to the lack of suitable organisms for the tests. (7) The solar collectors and the pilot-scale bioreactor light distribution panels for the deep-penetration hybrid solar lighting system have been designed. One solar lighting system (solar collector tracking unit, fiber optic light transmission cables, light distribution panels) is almost completely prepared for installation during the next quarter in the pilot scale bioreactor system. (8) Pressure drop results from tests on the enhanced mass transfer CO{sub 2} absorption technique (the translating slug flow reactor) are encouraging, with reasonable values of 2.5 psi maximum over an 11.48 meter distance between pressure taps for test conditions of 0.6 m/sec slug velocity and approximately 10 m/sec gas velocity. Preparations are under way for CO{sub 2} scrubbing tests.