الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Alexandria is the largest city with a permanent population of Three million and attracts an additional million tourists every year. The domestic solid wastes of the city reaches approxima tely more than a half million tons/year. These wastes make a problem in its disposal because the J collection service cover about sixty percent of the population, and the remaining one tend to put their refuse in the street which periodically set fire to it causes other environmental problems. Consequently, the only method of disposal is waste tipping and uncontrolled burning because the city is far from the desert area in which sanitary landfill could be constructed. Alexandria Governorate decided to resort to composting and a composting pilot plant was built in the middle district and opened in March 1985 and financed by a loan from the World Bank. NoW, each Governerate 15 demanding loans to built more composting plants including Alexandria Governerate and so , it is needed to study the operation efficiency and performance of these pilot plants before building new ones. In any compostinq process, energy-rich organic compounds are decomposed by bacteria and fungi to energy-poor organic compounds and salts. The release of energy in this process causes a rise in temperature. Due to the previous fact, this study which carried out to evaluate the fermentation process during the composting of domestic solid waste, included the physical, biological and chemical evaluations. Seven rUns were carried out during this study, r three runs at the Abbis compost plant and Four runs at th~- Institute premisis. It was meant that the time of the runs cover the seasonal variation along the year. The samples were taken from the windrow direc tly after formation by the conveyor and then followed by sampling each week during the fermentation and maturation processes. For the Institute runs, the material of selected wlndrow within the fermpntatlon area of the plant was collected directly after the conv~yer and transfered to the Institute to form a small windrow and then representative samples were taken from it weekly. The samples were taken from about 0.5 meter below the surface of the windrow. Each sample was composed of f~ur portions £rom different sites of the windrow and mixed well and then placed in sterile plastic bags, sealed, and transfered to the laboratory to be analysed. Temperature was measured daily within the windrow by using a thermocouple digital thermometer. The physical evaluation included the measuring of temperature and moisture during the composting processes. It was found that the high temperature range ranged between 74 to 18°C and the low temperature range ranged between 70 to 14°C during the Seven runs. The moisture percent ranged between 58, to 23 during the fermentation processes iril” over the different runs. The biological evaluation included the total plate’count , total and fecal coliforms , the presence of Ascaris ova, and the identification of fungus species which were present especially the pathogenic fungi (Asprigillus and Mucor). The results obtained from this evaluation showed that the total plate count were changable all the time due to the change in temperature range during each run. The fecal coliforms and Ascaris ova were absent in some runs (1 , 3, 5) ; and identified in others (4 , 6 , 7) which disiapeared later on , to reach count of zero organism. This was due to’ the higher range of temperature which also affected the pathogenic fungi. From the results of run 2 , it was noticed that the fecal coliforms were detected and decr.ased but lhe count never reached zero organism, this was attributed the temperature range which stayed only five days around GO.C. These five days were not enough for the complete destruction of the fecal coliforms. The last evaluation is the chemical one which included the measurements of some parameters: pH , N03 ’ NH3 ’ volatile solids, C , N and the calculated C/N ratio. It was found that the pH ranged from 6.6-9.5 , and Nitrate was increasing, while ammonia was decreasing along the time of the composting processes. Volatile solids and carbon were decreasing due to the microbial activity but nitrogen percent was increasing. The C/N ratio decreased and reached to its lower value (6.4) during run 4. The study revealed that the temperature and moisture content depends to some extent on the ambient temperature ftnrl climatic conditions durinq the season, so it recomended to have a larger ” ,dimensions of the windrow not less 180 cm ,in hight ( I and 300 cm in width at cold season. Also, it was concluded that the destruction of pathogenic organisms were occuring within two weeks, when the fermentation mass is maintained at a temperature above SS.C. The chemical evaluation indicated that the optimum pH reached during the fermentation process. The C/N ratio was a useful indicatpr decomposition of organic matter. of the rate of From the statistical analysis which were carried between the different evaluations, it was concluded that the physical, chemical, biological parameters were correlated with each other. The most important recommendation reached from this study that an item must be added to the decree of the ministry of Agriculture No. 100/1967. This item states that fecal coliforms , Ascaris ova and Asprigillus must be absent from the compost after the maturation process and prohibit the use of the compost after the fermentation process only. As the results proved the presence of some pathogenic organisms after the fermentation process.^leng