الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The study took place experimentally at the East Treatment Plant of Alexandria General Organization for Sanitary Drainage (A/GOSD) during the period 1993-1995. A pilot plant was constructed previously to investigate the efficiency of different treatment processes as plain . sedimentation, chemical precipitating, and activated sludge. Sludge samples were taken from the primary sedimentation tank, chemical precipitation tank and the secondary sedimentation tank using the activated sludge method for both plain and chemical settling. The work included the following processes. 1. Co-corn posting of sludge resulting from primary settling tank with domestic solid wastes. 2. Co-composting of sludge resulting from chemical precipitation tank using quick lime (calcium oxide) with domestic solid wastes. 3. Co-composting of activated sludge’resulting from secondary settling tank after primary settling with domestic solid wastes. 4. Co-composting of activated sludge resulting from secondary settling tank after chemical precipitation with domestic solid wastes. Co-composting take place by both the Forced Air Method and the Windrow Method. The work in this thesis is presented in nine chapters as follows: 1. Chapter 1 includes the-introduction denoting to the importance of the study to solve a problem of sludge final disposal. 2. Chapter 2 includes the relevant literature review during the last seventy years. This is in addition to pointing out: a. Sources and properties of sludge and different methods of its final disposal. b. Sludge volumes resulting from different treatment methods. c. Management and treatment of sludge. d. Treatment by co-composting through both method of Forced Air and Windrow methods. e. Effect of sludge treatment on infectious parasites. f. Sludge effect on Public Health and on the Environment. 3. Chapter 3 includes the Aim of the Work which is identifying the optimum methods of Forced Air and Windrow co-composting and their effect on parasite and heavy metals removal after applying on three types of calcareous, sandy, and clayish soils which are the existing soils around Alexandria. 4. Chapter 4 includes the Materials used and the Methods carried out in the work describing the research procedures from the beginning till reaching the results. 5. Chapter 5 includes the results reached at and the relevant discussion from which the following have been shown: a. Different results of sludge analysis showing parasite eggs and cysts before and after co-composting (Tables 1, 2, 3, 4). b. Different results of leachate analysis resulting from co-corn posting showing heavy metals (Table ’5, 6). c. Different results of leachate analysis at a depth of 90 centimeters after applying the co-compost on the three different soils (calcareous, sandy, and clayish) when irrigating with tap water. The analyses were carried out biologically, chemically and physically (Tables 7, 8, 9,10). e. Study of the effect of co-compost on public Health and the Environment. 6. Chapter 6 includes the conclusions and recommendations. A. Conclusions 1. Ascaris lembricoids eggs were found in all experiments for all sludges except that after chemical precipitation and activated sludge. With respect to that after plain settling and activated sludge, only one third of the experiments showed positive results. Entamoeba coiL Entamoeba histolytica and Qardia were found after all experiments. 2. Activates sludge after chemical precipitation gave complete removal of all parasites in all soils except for Ancylostoma duodenale which was found in the sandy soil. 3. Heavy metals concentrations in co-compost leachate gave a little bit more than 1 mg/l for both Forced Air and Windrow methods. Such results might be slightly more than that specified in Law No. 4 for 1994 which states that it shall be not more than 1 mg/l. 4. BOO and COD values in the leachate were found high in the clayish soil more than other soils due to its organic contents. B. Recommendations 1. Co-compost when useaas a soil fertilizer or soil conditioner should be after chemical precipitation since it gave highest removal of parasitic eggs and cysts. However primary settling is still preferable since it gave good removal at a reasonable cost. I 2. Protective clothing should be used as boots and gloves when dealing with co-compost. 3. Fertilizing vegetables that are eaten raw with co-compost should be prohibited. Relevant legislation should take place with its enforcing actions. 4. Health education campaigns for farmers should take place through different media to show them the public health risks of using co-compost . material without protective clothes. 5. Further studies are still needed to identify the minimum depth that a parasite can reach in each soil. 6. Further studies are still need to show the effect of heavy metals on composted crops. 7. Chapter 7 includes the relevant references which amounted to 95 starting from 1934 to 1996. 8. Chapter 8 includes the appendices of different tests which amounted to nine. 9. Chapter 9 includes the English and Arabic summaries. liowever in more abstracted summary the following is presented: The main objective of this study, has been stated to investigate the effects of different methods of sludge co-composting by windrow or forced air on infective stages of parasitic eggs, larvae and cysts in the (jiffercnt soils. Pllysco-chem ical analysis of !cachate of CO-( om posting ( periments were made. The different soils filtrates from c” (,nCOUS, sand. ;:j’nc1 (1;1\. soils uJling after irriqatinCl, \v’ith tap water an(1 i:-inq co-compo’..,r 1i,il( 1];11 by windrow and forced air were analysed for biological, physico-chemical, and heavy metals content. Results obtained from the study showed the following: 1. As regard the parasite, Ascaris lembrjcojds eggs were present in all types of sludge through all runs except in activated sludge. On the other hand Entamoeba coli, Entamoeba histolytica and Giardia were present in all runs for all types of sludge. 2. For the irrigated soils there was no difference among the three types of soils (calcareous, sand and clay) in the reduction of parasitic eggs and cysts. Le. sandy, clacarous, and clay soils retained parasitic eggs and cysts on their surface. 3. There were no eggs and cysts in the filtrate of the three types of the irrigated soils at a depth of 90 centimeters from soil surface. 4. The leachates contained high value of heavy metals in both co compost of plain sedimentation sludge with refuse and co-compost of . chemically precipitated sludge with refuse compared to co-compost of activated sludge of the same type. 5. The highest value of BOO and COD were 120 mg/L and 179 mg/L respectively in the filtrate of clay soil using co-compost product of chemically preciptited sludge with refuse by windrow. On the other hand the lowest value of BOO and COD were 71 mg/L, and I 14 mg/L 111 the filtrate of calcareous soil using co-compost product from nctivated sludge afkr chemically precipitated sludge with refuse by windrow.^leng