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Author Mani, Thomas ♦ Abanmy, Abdulrahman ♦ Hassan, Ata M.
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Sand Filter ♦ Soluble Glucose ♦ Seawater Feed ♦ Swcc Al-birk ♦ Acid Degradation ♦ Cellular Product ♦ Chlorine Demand ♦ Cellulosic Cellular Wall Structure ♦ Ro Membrane ♦ Feed Acid Demand ♦ Alkaline Medium ♦ Inorganic Nature ♦ Phytoplankton Cell ♦ Inorganic Matter ♦ Acidified Feed ♦ Acid Demand ♦ Sized Particle ♦ Small Sized Sand Filter ♦ High Ratio ♦ Trapped Matter ♦ Normal Seawater Feed ♦ Necessary Nutrient ♦ Large Size Ro Plant ♦ Soluble Product ♦ Pilot Plant Scale ♦ Ppm Glucose ♦ Sand-anthracite Filter ♦ Lipid Protein ♦ Acidic Medium
Abstract In an RO pretreatment system sand-anthracite filters trap and concentrate suspended matter of organic and inorganic nature, including phytoplankton resulting in a seawater feed with lower turbidity. When seawater feed is acidified ahead of sand-anthracite filter the acid reacts with the trapped matter, mainly with the cellulosic cellular wall structure of the phytoplankton, degrading it to smaller sized particles and soluble glucose. The soluble glucose is not removed by the sand filter and thus it flows with the filtrate along with other acid degraded cellular products, e.g., lipids & proteins. The concentration of these degraded products found in the filtrate is dependant on the amount of the phytoplankton trapped on and within the sand filter. In one of the experiments, over 16 ppm glucose was found in the filtrate collected from an acidified feed enriched with phytoplankton. Passage of such a feed with a high ratio of glucose and other products resulting from acid degradation on RO membranes containing living microorganisms provides them with the necessary nutrients on which they feed and can rapidly multiply. This process leads to an increased formation of biotilm on the membrane and may give rise to membrane biofouling. Another disadvantage of dosing acid ahead of sand filter is that it leads to a rise in the feed acid demand. Acid is consumed in the neutralization of the organic and inorganic matter which otherwise i.e., without acidification would have coagulated and trapped in the sand filter without their degradation into soluble products. In one case the acid demand for a phytoplankton enriched feed was about 38 % higher than that for a similarly treated normal seawater feed. Moreover, in an acidic medium the chlorine becomes more potent than in a neutral or alkaline medium, which contributes to the further destruction of the phytoplankton cells into smaller fragments and increases the chlorine demand. It is recommended to carry out this experiment, which was done using a small sized sand filter, on a pilot plant scale and if proved beneficial it should also be tried on a large size RO plant, e.g., SWCC Al-Birk
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study