本帖最后由 zadonwong 于 3-5-2012 12:57 AM 编辑
回复 964# kitoroneo RAS will accumulate dissolved organic materialand fine suspended solids between 5 – 10μm that are not easily removed byconventional methods of mechanical filtration and sedimentation (Timmons 1994). Foamfractionation is a simple, relatively low cost method for removal of fine suspended solids anddissolved organic material (DOM), originating from proteins that accumulate within RAS, andare ultimately responsible for water turning yellow or brown over time. This material comesfrom sources such as decomposing feed and faeces, urine and mucous. Foamfractionation works very well in saltwater in which foam production is easier, although it hasbeen reported to work in freshwater with high concentrations of dissolved organic material(Wheaton et al 1979). Foam fractionation used in RAS is a process in which air is mixed with water to formbubbles that concentrate fine suspended solids (generally < 30μm) and dissolved organics(surfactants) at the bubble surface. The bubbles and concentrated surfactants rise to thewater surface and form foam that can be easily removed from the culture system(Timmons 1994).Many types of foam fractionators are available. All are typically columns into which culturewater enters and fine air bubbles are introduced using diffusers or venturis driven bypumps. A collector at the top of the device (above the operating water level) receives andallows breakdown of foam to produce a concentrated solution that is discharged to theeffluent system.Additional benefits of foam fractionation include:• Reduction in ammonia due to removal of organics.• Removal of bacteria.• Increased pH through removal of organic acids (Wheaton et al 1979).
上次网上找到的，是给RAS系统的。但是会减少养份给菜，相对的鱼会比较开心吧.gif) | 
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发表于 26-4-2012 02:18 PM
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，分解最耗氧的。
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， strawberry tower.
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