With an increase emphasis on the planning and design of wastewater treatment plants (WWTP) in order to decrease environmental degradation of surface and groundwater resources in the country, the need for proper selection of treatment system will become critical.
Based on statistics, before the turn of the next century (1400), Iran will have 800 cities, most of them will be in need of WWTP.
A large capital and human investment is necessary to cater for the rising demand of WWTP facilities.
To date, little or no published data are available documenting the overal cost of various WWTP facilities in Iran. Considering the vast variations in the climatic conditions of the country, three widely used techniques for treating municipal wastewater, i.e., lagoon, activated sludge, and trickling filter were selected and designed for cities of 20, 100, and 500 thousand population in different regions of the country.
Design criteria are presented for each system and costs are summarized both for interest rates of 12 and 19 percent. Operation and maintenance cost were estimated and the annual cost was taken as the economic index for comparing different alternatives in different parts of the country.
The ultimate objective of this paper is to allow engineers and planners to estimate the potential cost of a WWTP and select appropriate treatment systems for each climate.
( 1M. Abbaspour, Ph.D., 2F. Atabi, M.S. )
1- Sharif Universinty of Technology 2- Faculty Member of Islamic Azad Universinty
Keywords : Renewable Energy , Wind Energy , Development programme , Energy Economic , Development of the Environment , improvement Abstract :
On the verge of a new era, the modern and industrial societies become more dependent on the utilization of a tremendous amount of energy, most of which comes from fossil fuel resources.
The industrial growth of developing countries, the increase in world population, attention to public health and the development of transportation systems are among the factors which constantly affect the increase in world energy demand. At present, the utilization of energy by developed countries is close to twice that of its use in less developed countries, eventhough their population is one third of that in less developed countries.
Studies have indicated that continuous supply of nuclear and fossil fuel resources of energy will create numerous problems. In this article these problems have been reviewed and emphasis placed on the need to pay more attention to the utilization of renewable energy.
It is shown in this research, that out of 25000 MW available potential of hydropower, less than 9% is currently utilized. From 45 selected sites located in 26 regions, more than 6500 MW electricity can be generated by wind power. It is also shown, eventhough solar energy has a good potential in Iran, still it can not be used commercially. The energy from waves does not have a promising future and its potential is limited to a few hundreds of megawatts.
In this article different methods of renewable energy production were studied for Iran and their role in long term sustainable development programmes in the energy sector were reviewed.
( M. Ghiassedin, Ph.D., S. Nasseri, Ph.D., A. Mesdaghinia, Ph.D., R. Dianati Tilaki, MSPH )
Tehran University of Medical Sciences, Dept. of Environmental Health Engineering
In this research, the application of hydrogen produced by methanol dissociation as an alternative fuel in vehicles was studied, with the major objective of pollution reduction in exhaust gas.
Methanol dissociation was provided through a thermal & catalytic process, in a reactor packed with the catalyst (CuO- ZnO) and equipped with electrical element. The gaseous products were conducted into the gas- air mixing unit and the fuel mixture (basically H2 AND CO) and air, was fed in the manifold of a spark ignition (SI) engine.
Different runs of the SI engine with this fuel and also with gasoline were investigated, and results of the exhaust gas quality were compared.
Results indicated that by the application of this combustible mixture (H2 and CO) , emission of air pollutants such as Carbon Monoxide (CO) , Carbon Dioxide (CO2) and Hydrocarbons (HCs) was significantly reduced.
In many countries as in Iran, water treatment plants are mostly designed for removing nondissolved contaminants and no special process is provided for the control of organic micropollutants. As process developments are not always economically feasible, upgrading the exiting plants may be sometimes considered as the best solution?
Adsorption by activated carbon (GAC and PAC) is one of the best suitable processes, which can be employed for micropollutants removal from drinking water. Both forms of carbon are useful, but application of PAC may be more feasible in conventional treatment plants, because it provides grater degree of freedom in the point and the time of use.
In this research, adsorption of phenol and one detergent sample (as 2 prevalent organic materials found in water resources) are compared in bench scale, and the effects of various parameters on adsorption are determined at batch system for two types of PAC (PAC manufactured in Iran and from Merck Co.). Results Showed that the maximum rates for phenol and detergent adsorption occurred at the first 15-20 min. of contact: 59- to 72.5% of total adsorption for both adsorbates (in 2 hours) have been occurred at the first 15 minutes for both kinds of PAC.
Addition of Merck’s PAC dosage>30 mg/l and PAC manufactured in Iran>50 mg/l had not any significant effect on adsorption efficiencies. Increasing pH had an undesirable effect, but in natural pH range of water resources, there was no detectable effect on phenol and detergent adsorption.
This paper also describes the advantages of selection the alternative points, which are considered to be permissible for PAC addition in a conventional treatment plant from the point of view of feasibility, final water quality and required PAC dosage.
( M. Moghtader )
Tehran Province Bureau of Standard and Industrial Research
Keywords : Standard , Environmental Management , ISO Certificates Abstract :
During the recent decades human activities for development, have provided basically and international difficulties for environment. Environmental management science is responsible to maintain balance between economical development and environmental protection, and by establishing environmental management, system can adjust the effects resulting from development and decrease environmental problems.
This system has systematic performance integrated with overall management and commitment form all levels especially from top management. International standard organization assesses the need for standardization in the area of environmental management, and develops voluntary international standards in order to establish coordinate environmental management system in an organization.
According to the statistics (July 1998) 700 EMS certificates were issued in the world. Half of them are on the basis of BS 7750 and with the launch of 14001 in 1996, companies registered to BS 7750: 1994 are required to transfer form BS 7750 ISO 14001 by considering 18 aspects.
Comparison of ISO 9000 and ISO 14000 certificates in different geographical regions shows that developing countries have also taken necessary actions towards management systems and have established the system with regard to available possibilities.
In Iran the number of ISO 9000 certificates are nearly 80, which include various industries. Five ISO 14001 certificates have been issued by October 1998. These companies have been able to perform environmental management system.
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