الفهرس 
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Abstract
Edfina drinking water purification plant is located at the end of Rosette branch where minimal water flow, stagnant water and heavy pollution loads from illegal discharging of agricultural, industrial and domestic wastes without treatment. These lead to higher levels of concentrations of compounds causing taste and odor in surface water especially in winter and spring. In addition, the Ministry of Irrigation and Water Resources usually reduces the water flow of River Nile (annually) in winter and spring due to the lower rates of agricultural water consumption. This magnifies the water pollution consequences along the River Nile and its branches especially at the ends.
Drinking water palatability depends on its purity from substances causing taste and odor. Simple and complicated compounds such as ammonia, mono, di, and tri-chloramines, total organic carbon, Some species of algae, bacteria and other microorganisms change taste and odor.
Conventional treatment processes in water treatment plants, such as coagulation, sedimentation, filtration and chlorination have been found to be ineffective in water quality improvement in terms of taste and odor causing compound. Consequently development of advanced effective technologies became essential. The use of activated carbon in removal of organic and inorganic taste and odor causing compounds in water purification plants is the wide broad spectrum technology available. Other study concluded that the higher significantly percentage reduction were found when optimum combined doses of alum and powdered activated carbon, which means enhanced coagulation technology, were used as compared to the use of optimum doses of alum alone under conditions of water treatment with and without pre-chlorination. This technology may be hardly afforded in most of developing countries due to the higher costs and limited availability of allocated fund.
This study aimed to evaluate the use of Bio–char yield from pyrolysis of agricultural residues in advanced treatment of drinking water in Edfina Water Purification Plant.
An experimental studies were included two phases, Coagulation studies and bio-char filter studies.Three sites at Edfina Water Purification Plant (raw water, after pre-chlorination and afterfilteration)were selected.Two Water Samples were collected from each selected site monthly during winter and spring from 2015-2016.
At present study enhanced coagulation performed by Jar test using the most suitable dose of alum 30mg/l in spring and 40mg/l in winter which was obtained from preliminary experiments combined with different doses (0.5, 1, 1.5 and 2 g/l) of three types of bio-char (RHBC, SDBC, and RSBC ) in spring and winter without and with pre-chlorination sites to adjust the dose of different types of Bio-char adding.
Results of phase one (coagulation study) revealed that ;When using different doses of RHBC and SDBC, water turbidity reduction ranged from 74% to 79% in spring and from 58% to 62% in winter when pre-chlorination was not applied and from 77% to 81% in
spring and from 67% to 71% in winter when pre-chlorination was applied. While RSBC recorded low reduction values in spring 54% to 65% and in winter 52% to 57% in case of without pre-chlorination. When pre-chlorination applied recorded 66% to 72% in spring and 57% to 61%.the more effective dose in all types was 1g/l.
However the reduction in total algae count for clarified water with three types of bio-char ranged from 66% to 77% in spring and 64% to 72% in winter in case of without pre-chlorination and from 74% to 83% in spring and from 64% to 75% in winter in case of with pre-chlorination. It was noticed that The results of RHBC and SDBC better than results of alum alone. While the results of RSBC slightly low than the results of alum alone.
On the other hand the reduction in TOC with different doses of RHBC, SDBC and RSBC ranged from 16% to 30% in spring and from 21% to 30% in winter in case of without pre-chlorination, While ranged from 31% to 50% in spring and from 29% to 46% in winter when pre-chlorination applied. It was very closed to the results when alum alone with high dose used (80mg/l). RHBC and SDBC recorded high values in all condition of treatment while RSBC recorded low values.
While ammonia reduction with different doses of RHBC, SDBC and RSBC ranged from 13% to 25% in spring and winter in case of without pre-chlorination, Whileranged from 39% to 50% in spring and from 27% to 36% in winter when pre-chlorination applied. It showed that slight high reduction percent results than the results when alum alone with high dose used. Also RHBC and SDBC recorded high values in all condition of treatment while RSBC recorded low values.
But the removal percent of TON with different doses of RHBC,SDBC and RSBC ranged from 50% to 65%in spring and from 53% to 70% in winter in case of without pre- chlorination. While ranged from 61% to 74% in spring and from 60% to &71% in winter in applied pre- chlorination. These results higher than the results obtained when used dose of alum alone 50 mg/l in spring and80mg/l in winter.
This phase detected that, The results obtained by RHBC and SDBC much better than results of used alum alone with high dose especially in removal percent of TON and TAC. Which considered the main factors in determine the quality of drinking water.
The results obtained by RHBC near to the results of SDBC in all parameter in different condition. Paired t-Test showed that there was no significant difference between two type in different condition.
The results obtained by RHBC and SDBC much better than the results of RSBC in all parameter in different condition. Paired t-Test showed that there was a significant difference between results of RHBC, SDBC and results of RSBC in different condition.
As a results of Cost-Effectiveness Analysis, it can be decided that the best alternative in coagulation at Edfina WPP using the dose of alum 30mg/l in spring and 40 in winter combined with dos of 1g/l RHBC and SDBC.
The aim of phase II of this study was to evaluate the performance of the bio-char as filter media to produce high quality drinking water. Designed pilot filter was used to investigate the ability the three types of the bio-char (RHBC, SDBC and RSBC) in water
quality improvement. The water samples used in these experiments was collected from influent of sand filter, effluent of sand filter which is the influent of Bio-char filter and the effluent of bio-char filter.
This phase detected that, After extra filtration by using RHBC and SDBC filter, Turbidity recorded more reduction percent 17% and 22% respectively than the results of sand filter, While RSBC filter recorded low reduction percent 3.4%. TON and TTN after extra filtration by using RHBC and SDBC filter, recorded high reduction percent 65.5% than the results of sand filter. While RSBC filter recorded slight low percent reduction52%.
More removal percent of residual and combined chlorine after extra filtration by using RHBC, SDBC and RSBC filters ranged from 81% to 89%, Increase chlorine in drinking water causes many problems such as the taste and odor and chlorinated by-products. Total organic carbon recorded percent of reduction ranged from 16% to 21% after extra filtration by using RHBC, SDBC and RSBC filters. Total Heterotrophic Plate Count recorded percent of reduction ranged from 35% to 58% after extra filtration by using RHBC, SDBC and RSBC filters. Also, more reduction percent was recorded in Total algae count after extra filtration by using RHBC, SDBC and RSBC filters ranged from 34% to 42%
Paired t Test showed that, Significant difference between the results of RHBC and SDBC filter and the results of sand filter.
All the analyzed parameter after all types of filters were complied with Egyptian limitation for drinking water quality Standards, 458/2007.
Study recommended that:
1. Application of using bio-char as coagulant aid in drinking water purification plants to protect public and environmental health due to:
- Reduce alum dose.
- Prevent or reduce pre-chlorination.
- Avoid release of algal toxin to water.
- Prevent produce trihalomethanes.
- Solve the taste and odor problems.
- Reuse of produced sludge in agicultural activities.
- Eliminate of black cloud.
2. Extra filtration by bio-char filter should be installed after rapid sand filter to overcome taste and odor problems.
3. Imported activated carbon should be replaced by locally produced bio-char, It is cheaper in price, provides foreign currency, gives results approximately near to it and helps in the safety disposal of the agricultural waste to protect the environment
4. Government departments should be encouraged production of bio-char in large scales to increase and mainstream the use in water purification plants to facing the new challenges in drinking water in Egypt.
5. Further researches are needed to evaluate the relationship between bio-char and pre-chlohination.
6. Further researches are required to improve the efficiency of locally produced bio-char.