الفهرس | Only 14 pages are availabe for public view |
Abstract Ras Abu Jarjur (RAJJ) desalination plant in Bahrain is considered the largest Reverse Osmosis plant in the Arabian Gulf countries to desalinate the high brackish well water in order to obtain potable water. This plant uses DuPont B-lO membranes for the purpose along with both Sodium Hexa Meta Phosphate (SHMP) and Sulphuric Acid as antiscalants. This thesis aims to study the possibility of replacing both SHMP and the sulphuric acid with another antiscalant which is FLOCON 100, manufactured by Pfizer Chemicals International Co. The study is based on carrying out all the tests and experiments through an actual operation for a laboratory model (a reverse osmosis pilot plant) which is similar to the main RAJJ plant and which contains 10 DuPont B-lO membranes. The author of this thesis had designed this pilot plant, operated it, took its operating data and results and analysed its results. Pfizer Chemicals Int. gave all the financial support to build this pilot plant, and gave all the chemicals and instruments needed to complete the job. All the tests and experiments were completed successfully during the period from February 1988 to March 1989. As a result of these tests, the thesis confirms and demonstrates the following significant points: 1. FLOCON 100 Antiscalant is an effective product for inhibiting the formation of scales on Du Pont B-lO membranes with the use of the high brackish water. It is also an effective replacement for both SHMP and Sulphuric Acid as it acts as a threshold inhibitor which interfere with the crystallization of Calcium Carbonate, Calcium Sulphate, Barium Sulphate and Strontium Sulphate scales. 2. The use of pH of the addition. 100 as it (4-11). FLOCON 100 will permit operation at the natural feed water and eliminate the need for acid This fact is a result of the stability of FLOCON is hydrolytically stable over a wide range of pH FLOCON 100 does not permit the growth of the bacteria due to its polymeric nature and its low pH, unlike SHMP which is a good food for the bacteria due to the high content of phosphates . FLOCON 100, when used at the recommended dosage rates, offers significant savings in chemical costs because of its low dosage compared to the high dosage of both SHMP and Sulphuric acid. The results also confirm that the use of FLOCON 100 will significantly reduce fouling of the micro guard filters, prolong the life of the filter elements and reduce the frequency of changing it, and accordingly offers potential savings in the filter and labour costs. |