الفهرس 
Chapter 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
The problem of handling liquid and solid wastes is one of the constraints facing environmental and health development in the Egyptian village. Moreover, the high capital, operation and maintenance costs of implementing traditional waste handling systems limit expanding the scope of service in such communities.
The ultimate goal of this study is to develop an appropriate and economically sound method for treatment of night soil. The study in general encompassed different aspects pertinent to adopting aerobic co-composting of night soil and agricultural residues. Thus, it may be possible to treat wastes in an environmentally safe way in addition to production of soil conditioner of desirable characteristics. The real i zati on of the stated goal impl i ed the identificaiton of the effect of different variables on the efficiency of co-composting of night soil and available agricultural residues (rice straw, maize stalks and cotton stalks). The variables of concern and magnitude of changes were, moi sture content (43% - 65%), carbon to nitrogen ratio (20-35), turning frequency (2-4 days) in addition to the type of bulking material (agricultural residues).
The experimental study showed that the optimum conditions for co-composting are:
- Moisture content 55%.
- Carbon to nitrogen ratio 25-30.
- Turning frequency every 4 days.
Also rice straw and maize stalks are suitable residues for co-composting. Additional work is still needed to develop suitable methods for pre-treatment of cotton stalks.
The above-mentioned optimum conditions have been utilized to explore the chemical changes during co-composting. Empirical realations have been developed expressing time dependance of CIN ratio.
The obtained results enabled development of a technooeconomic study for treatment of night soil in shosha village (27000 inhapitant) based on co-composting process.
The initial capital and annual operating costs are LE 167873 and LE 60137 respectively. Further, the net production cost is LE 4.4 per cubic meter. The proposed co-composting plant may realize simple rate of return ranging from 14% to 23%.
The study proved the viability of co-composting of night soil and agricultural residues as an appropriate.