اسم المؤلف:
رائد كاظم عبد الاسدي
اسم المشرف:
فؤاد منحر علكم | حسين يوسف الركابي
المستخلص:
اجريت الدراسة الحالية على نوعين من المياه العادمة الصناعية المطروحة من مصنع نسيج الديوانية والمياه العادمة البلدية من محطة معالجة الديوانية، وللمدة من ربيع 2011 الى ربيع 2012 وهدفت الى اجراء مراقبة فصلية لنوعية المياه الداخلة لمحطتي المعالجة والخارجة منها | The current study has been conducted on two types of waste water, industrial wastewater from Al - Dewaniyah textile factory station1, station 2 and municipal wastewater from Al - Dewaniyah wastewater treatment plant station 3, station 4 in the City of Al - Dewaniyah - Iraq., for the period from Spring2011 to Spring 2012 and targeted monitoring quarterly the quality of water entering and leaving the stations.The study also includes the evaluation of the efficiency of some algae and aquatic plants to improve water quality via bioremediation of some pollutants in the water. The evaluation of water quality includes18 parameters as confirmed on spatial and temporal changes of these parameters, as well as the algal contents of these four stations(S1, S2, S3and S4). The results of physical and chemical analysis show the following ranges of : temperature (12.5 - 41.5°C), total dissolved solids TDS(692 - 1384.6 mg/l), total suspended solids TSS(58 - 277.4 mg/l), electrical conductivity EC(1225 - 2045µS/cm2), pH(7.0 - 7.8), dissolved oxygen DO(0.7 - 8.51mg/l), biological oxygen demand BOD(48.82 - 205 mg/l), total alkalinity (170.7 - 428 mg/l), total hardness TH (412 - 1623.3 mg/l), calcium (89.7 - 204.14 mg/l), magnesium (37.7 - 332.5 mg/l), nitrite (0.43 - 12.25 mg/l), nitrate(6.18 - 63.75 mg/l), phosphate (0.813 - 20.24 mg/l), lead (0.0983 - 1.076 mg/l), chromium (0.007 - 0.045mg/l), cadmium (0.0374 - 0.326 mg/l) and the total algal number(17.00 - 14202 individual/l).The spatial and temporal variations show significant differences at(P?0.05) among studied factors in the different stations.The qualitative study of algae reports that the dominance is to the blue green algae(Cyanophyta)by 46%, then is followed by diatoms(Bacillariophyta) by 26% down with Dinophyta3%, according to Shannon - Wiener index of diversity (H), the fall and winter classified as severely polluted all around the stations 0.377 and 0.669, respectively, while summer and spring are moderate pollution of a category (II) and the values of (H) is1.374 and 1.395 respectively, in situ has been observed that the stations are classified as highly polluted and have been ranked within the category(I) and the stations arranged according to the pollution as S3 <S4< S2< S1.According to Species richness index the first station S1 is the best, follows by S4, S3 while S2 comes the last in order, but in the terms of total abundance has topped the third station S3 among the others, then followed by S4, S2 and finally S1. on the other hand the current study includs laboratory investigation to demonstrate the efficiency of algae and aquatic plants to improve water quality as it has been experimenting with immobilization of algae technique, a new method has been used for the first time at the local level in the current study. The results show that the immobilized algae Stigonema sp.and Cladophora glomerata have lowered the pH of the treated wastewater which began relatively high, as well as increasing dissolved oxygen concentrations at the end of the experiment all transactions free and immobilized treatments , on the other side TSS has been reduced about 61.8% when treated with immobilized algae C.glomerata, nitrite has also been reduced at about 96.7% and 85.5% by Stigonema sp.and C.glomerata respectively, nitrate also has been reduced by 99.9% and 95.2% when treated with Scendesmus dimorphus and C.glomerata respectively, while the removal of phosphate reaches its peak when it has been treated with free Stigonema sp. and immobilized S.dimorphus by 99.92% and 98.35% respectively.The tested algae shows a great ability to reduce heavy metals, when immobilized alga Oscillatoria sp. removes about 94.27% of Lead, while free Stigonema sp. and C.glomerata are the best in Chromium removal about 92.42% and 92.35% respectively, and the C.glomerata is the best in Cadmium processing, a reduced rate of 99.21% followed by immobilized S.dimorphus of 97.13%. The current study also involves a laboratory experiment to evaluate the potential of two aquatic plants duckweed (Lemna minor L.)and water hyacinth Eichhornia crassipes Mart.(Solms.) in improving the quality of wastewater the tested plants have been worked at increasing the aeration of treated water by raising dissolved oxygen concentration about 85.26% and 84.4% for duckweed and water hyacinth, on the other hand the relative efficiency to reduce the pollutants by aquatic plants as follows : EC, NO2, NO3(31.66% and 28.45%, 55.7% and 50.01%, 55.7% and 13.3%)for duckweed and water hyacinth respectively, from another side water hyacinth is the most efficient in phosphate reducing at rate of 90.5% comparing with duckweed 49.78%.On the of heavy metals treatment the tested plants show a remarkable removal of lead 88.23% and 80.4% , chromium 97.84% and 95.18% for duckweed and water hyacinth respectively, with respect to cadmium, water hyacinth shows high efficiency in the removal of this metal by 98.14%, while duckweed is the least in the treatment of Cd by 81.8%. From the above results, the current study demonstrates that there are a spatial and temporal variations regarding the factors examined in the stations of wastewater treatment units and confirms that the efficiency of studied wastewater treatment stations is below the required level, which contributes in increasing the pollution of Al - Dewaniyah River, which is the unique source to supply the city with freshwater for all purposes, that receives large loads of pollutants.The study also confirms that the evaluation of the presence of algae in the studied stations.Thus the knowledge of algal composition could give an early warning and accurate assessment about the quality of sewage before dumping into river. In addition to the forgoing, it is concluded that the biological treatment (bioremediation) of wastewater using free and immobilized algae and aquatic plants have improved dramatically and tangibly the benefits of the quality of that water being a promising approach of the wastewater treatment as well as being low cost economically.
