الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The aim of this study is to investigate the ability of alternative treatment techniques to treat Alexandria liquid wastes for land application systems. This goal was designed to be reached by passing through three main targets. The first, was to study the treatability of Alex. waste water by tradi tional method of treatment technology that could be available at Alex. treatment plants. The chosen treatllient processes are: A-Preliminary treatment 1-Screening. B-Primary treatment, including: 2-Plain sedimentation. 3-Chemical precipitation. C-Secondary treatment, including: 4-Plain sedimentation followed by activated sludge process. 5-Plain sedimentation followed by trickling filter. 6-Chemical’precipitation followed by activated sludge process.. 7-Chemical precipitation followed by trickling filter. The evaluation of the treatability of wastewater by treatment processes was based on the percentage removal of the treated effluents turbidity, settleable solids, total solids ,. volatile solids, pH , chlorides, total hardness, . magnesium hardness, BaD, COD, phosphorus, and ammonia. The second target was to investigate the possible gains which may be achieved by Alex. wastewater re-use in crop rising ”CORN” , through the irrigation of raw and/or treated wastewater effluents on different types 0 f soils which are more prevelant around Alex. gover¬ norate. The selected three types of soils were clayey soil ”ABISS” , calcareuous soil, and sandy soil. The expected possible gains were represented by the planted corn productivity, dry weight, and height. The thlrd target was to determine the extent of possible groun-dwater pollution by the seeped water prl ,COD, volatile solids, end dissolved solids concente¬ rations, which leached from the soil root zone, upon applying raw or treated wastewater effluehts to each of the selected three types of soils. The study plan was Carried out through three stages. The first stage was the preparation of the pilot equipm¬ ents and the irrigation systems. A pilot plant was designed and built up representing all required diffe¬ remt preliminary, primary, and secondary treatments. Nighnty six barrels were prepared to be used as lysimeters filled with the three selected soil types. Each barrel was prepared to collect the seeped water from the root zone. The second stage was the operation of irrigation sy¬stems and the pilot plant, which treat 18m3/day ofAlex. liquid waste by the different primary and secondary treatment units . The second stage started when corn seeds were planted on the selected three soil types, and irrigated by 8.42 cm/week from each of the pilot plant different effluents. Regular samp~es were Qollected , represen¬ ting the different pilot plant effluents, and the seeped water from the soil. Plp-nt meesurements were also carried out, during the corn season until the corn were harvested at the end of the second stage. The third stage include statistical analyses of the collected data from the physical, chemical, and bioche¬ mical analyses of the second stage samples .and measureme¬ nts. The results of this study were summarized as follow; A- Alexandria wastewater treatability,as shown in tables(S;)&(S2) l-Alexandria liquid waste showed organics loads, ranged from medium strength to a very stromg wastewater. 2-Plain sedimentation of Alex. wastewater succeded to achieve maximum of its desired efficiency. 3-Plain sedimentation of wastewater showed a reduction of 61 settleable solids, 22 total solids, 43 volatile solids, 37 BOD , 36 COD, and 43ammonia. 4-Chemical precipitation achieved more removal of the treated wastewater settleable solids and COD. 5-Chemical precipitation is not recommended to be used prior to biological treatment processes. 6-Biological treatment. represented by trickling filter and activated sludge processes, showed less efficiency than those expected. Only from 60 to 65of the treated waste water BOD and COD were removed by the pilot pl~nt biological treatment units. This may be due to the inhibiting effect induced by the presenoo of industrial wastes combined Alex. domestic wastewater . to 7-Secondary treatment treat plain settled wastewater are more efficient than that treat chemically precipitated one. 8-Activated sludge processes showed more efficiency than I trickling filters, Based on BOD I removal. 9-Activated sludge process treat chemically precipi¬tated wastewater showed the maximum turbidity and settl¬ eable solids removal. lO-Activated sludge process treat plain settled waste water showed the maximum BOD , COD, and phosphorus removal . B-Wastewater re-use. as shown intables(S3)&(S4). ll-The soil type factor is the effective factor to deter¬ mine the possible gains and benefits achieved by Alex. re-use for rising cro~s. l2-Clayey soil provide favourable conditio~”for the planted corn to grow and produce maximum corn productivity , height, and dry weight; followed by calcareuous soil. l3-Sandy soil could not deal with the excessive amount \ of organic matter and toxic compounds present on Alex. raw wastewater , or even primary treated effluents, which may distroy the plant growth. l4-Corn ”height is dependant on the soil type factor and the wastewater water value, not on the fertilizing value of raw or treated wastewater effluents. , 15-Insignificant difference was found between corn height irrigated by water and those corn irrigated by Alex. untreated liquid waste, on all types of soils. 16-Alex. wastewater treatment, especially secondary treatments, are recommended prior to land irrigation sy¬ stems, to provide organlc compounds in a simple form available to the plant, leading to maximum crops yield and dry weight. l?-Plain sedimentation prior to trickling filter is. the most suitable treatment process gives maximum corn yield for clayey soil. 18-The recommended treatment for both sandy and calc¬ areuous soil to produced maximum corn productivity, is plain sedimentation. prior to activated sludge process. C-Alex. liauid waste re-use and its impacts on ground water pollution. as shown in table (55). 19-5oil type used is the significant factor affecting pH” COD, volatile solids, and dissolved solids concentr¬ ation of the infiltrate waster, which seeped from the soil and reach the ground water. , 20-The infiltrate water pH ranged from 6.6 to 8.0 for clayey soil, from 6.1 to 7.8 tor calcareuous soil, and from 7.2 to 8.7 for sandy soil. 21-Treatment of the irrigation wastewater by plain sedimentation followed by activated sludge process or tri¬ckling filter, will reduce more than 70 of the infiltrate water COD leached from clayey soil, which was of 40 mg/l. 22-Irrigation wastewater treatment by plain sedimenta¬ tion followed by trickling filter, will reduce 58of the infiltrate water COD leached from calcareuous soil, which reduced to minimum COD concentration of 57 mgll . 23-Primary and secondary treatments,prior to Alex. liquid waste re-use for land irrigation,has no effect in reducing the infiltrate water volatile solids, and dissol¬ ved solids concentratlons to any significant level. 24-Infiltrate water volatile solids concentration,lea¬ ched from soils irrigated by Alex. raw and treated waste water, ranged :from 231 to 842 ng/l for sandy soil, from 2035 ~o 6205 ~l for calcareuous soil, and from 1603 to 2150 ~l for clayey soil. 25-Infiltrate water dissolved solids concentration, , leached from soils irrigated by Alex. raw and treated waste water, ranged from 454 to 2079mg/l for sandy soil, from 6449 to 8792 for c~ayey soil, and from 8259 to 12,524 mg/l for calcareuous soil.