ABSTRACT
In this research, the effect of using vermicompost on growth rate, fertility and characteristics of tomatoes has been studied. Four vermicompost: soil mixture were supplied with ratios of 1:1, 1:2, 1:3, and 1:4 and also four different beds were provided. Total of 24 small globe tomato plants were tested and in each bed combination, six tomato plants were embedded. Rate of growth and yielding of plants grown in each of four beds were investigated in two periods of 40 days and 90 days after planting. The results showed a significant rise in growth of tomato plants by increasing ratio of vermicompost combined with soil. Obviously, the plant was mostly appeared in the main stem of the plant and there was no significant enhancement in the number of leaves. The main stem diameter, height, the number of leaves per plant, and yielding of tomato plants obtained the highest rate in four tested beds after 40 days in vermicompost to soil ratios of 1:3, 1:1, 1:3, and 1:2, respectively. In aforementioned observations some changes were made after 90 days of testing and maximum yielding and height of tomato plants were obtained in 1:1 ratio. Vitamin C and total sugar content in tomatoes increase with using vermicompost. The maximum amount of vitamin C and total sugar, soluble solids, insoluble solids and total nitrites of fresh tomato were observed in ratios of 4:1, 4:1, 3:1, 2:1 and 3:1, correspondingly
ABSTRACT
Tehran has a population of over 12 million and produces more than 7500 tons of waste every day. Tehran's municipal solid waste is processed and landfilled at Kahrizak disposal center. Due to inappropriate waste management, a lake with a leachate volume of 180,000m3 has been formed. To solve this problem a leachate treatment plant is currently under construction. A byproduct of leachate treatment is biogas. In this study, the feasibility of electricity generation using biogas has been investigated. Considering that 68.81% of the waste is degradable, the produced leachate has a high organic load [COD = 53900 mg/L and BOD = 34400mg/L]. The results showed that a power plant with a capacity of 1.8 MW could be constructed in the site. This electricity can be utilized in Kahrizak Disposal Site and also sold to the network [10 US cents/ kilowatt]. Financial analysis using ProForm software shows 1.3 years of payback period and emission reduction of carbon dioxide equal to 5752 tones/year in comparison with the natural gas power plant. Therefore this project is financially feasible for private investors with internal rate of return equal to 77% or more