| 摘要 |
<p>1495709 Floating cultivation of algae and bacteria BRITISH PETROLEUM CO Ltd 16 Jan 1975 [28 Jan 1974] 3806/74 Heading C6F [Also in Division B7] Chloroplast-containing plant cells, including unicellular algae, and photosynthetic bacteria are separately grown during passage in liquid nutrient suspension through a series of compartmented tubes 21 held in a rigid framework 23 forming a raft which is rendered buoyant by ballast tubes 24. According to the preferred features, the tubes are made of transparent low density polyethylene (though the undersides may be opaque), are compartmented throughout by a partition 22 and are joined together in a zig-zag fashion to provide for continuous flow through the whole series of upper and lower compartments, respectively. Radiationabsorbing substances, capable of absorbing radiation in the near ultraviolet and fluorescing at about 430 nm may be incorporated in the material from which the tubes are made. The plant cells are grown in the upper compartments with full exposure to the light, the photosynthetic bacteria being propagated underneath in the lower compartments. A heat pump may be used to circulate the suspension of plant cells. Air enriched in carbon dioxide is bubbled through the liquid suspension in the respective upper and lower compartments in co-current or countercurrent flow to that of liquid suspension. The temperature of cultivation may be monitored through a temperature sensing device by varying the relative amounts of gas and liquid in the compartments or ballast tubes, whereby to regulate the depth of immersion in the water. The device may also regulate the requisite amount of carbon dioxide supplied for the photosynthesis. The tubes when full of liquid typically have a depth of 10-80 cm.</p> |
