Wastewater reclamation and reuse is one of the best alternatives for compensating water shortages. Water supply and environmental conservation can be met through wastewater reclamation. Principally, treated wastewater is a reliable water resource, especially for periodic droughts and in arid areas. This study designed and implemented to investigate the full scale application of effluent for irrigation use. A major objective of this study is to assess on health effects and feasibility of crop irrigation by using stabilization ponds effluent of southern Hovaizeh Wastewater Treatment Plant located in Khuzestan Province. Two experimental plots of about 0.5 ha. were constructed. One of the plots irrigated by stabilization pond effluent and the other irrigated by Nisan River water. Basic parameters in two plots such as type of cultivated crops, amount of fertilizer use and lack of soil contamination have been similar in both. The only difference was the type of water applied for irrigation of agricultural crops. It was shown that high salinity of soil reduced the growth rate of agricultural crops. So, removing salinity from area should be performed before cultivation. Results gained on agricultural crops growth in two studied plots showed the growth rate and quality of crops were increased by using of stabilization pond effluent in comparison with Nissan River water.

User-friendly and low-cost wastewater treatment plants are good options for treating wastewater of small communities. The effluent of these treatment plants can be improved by various methods including using a horizontal rouphing filter (HRF). In this paper, HRF performance was evaluat by passing the Parkandabad wastewater treatment plant effluent through pilot scale constructed HRF. The HRF was constudted with fourcompartments of different sand sizes and was operated under three filtration rates of 0. 5, 1 and 1. 5 m3/m2. h. The results obtained from this study showed that the HFR performed the best at filtration rate of 0. 5m/h when the removal efficiency for BOD5 and COD was 61 and 63 %, respectively. Optimum removal efficieny of BOD5 and COD up to 65% could be achieved with an extended filtration run length. However, longer duration of filter operation after 4 months, reduced the filter performance for BOD5 and COD removal efficiency to 56. 8 and 61. 5%, respectivel. In conclusion, by using 4-compartment HRFs, compared with the conventional 3-compartment filtration, it may be possible to produce effluent quality for BOD5 and COD that is permissible for agricultural irrigation purposes.

Sewage stabilization Ponds are basically a number of earthen basins with retention times from a few days to weeks, depending on environmental conditions. Treatment in these lagoons is a natural process, and with proper design, construction, and operation, effluent quality would be suitable for agricultural irrigation from the chemical and biological aspects. An ISP pilot plant which was constructed to the eastern side of Shoosh Sewage treatment Plant in southern Tehran, and included Fermentation Pit Facultative pond, High rate pond and Maturation pond, was put to test and study during March 1999-2000 (Iranian Year 1378). The system was designed for an average sewage inflow of 4 m3/day and 20 days retention time. The sewage flow into the Fermentation pit was kept as up flow in spring, fall and winter seasons and as down flow in summer. To check the efficiency of the treatment process, COD, BOOS, TSS, total Nitrogen, total Phosphorus and fecal coliforms were tested and compared during the four Seasons of operation.The result of the research shows that in spring the global efficiency of the pilot was about 8% better in than summer, which can be attribute to the up flow in pit fermentation. In winter, the removal rate of HOD, COD and TSS were on the average 6% more than in summer, which was due to the role of effluent recycling. This research indicates that the facultative pond with internal pit fermentation has principle role for removal of pollutant (70% removal).Finally, it could be concluded that an ISP system is an efficient process that ensures high treatment of municipal wastewater and reduces detention time in the pond system. It is especially recommended for small to medium size communities.

History and Objectives: Considering the high cost of mechanical treatment of wastewater, and the necessity to investigate more economical methods, specially the ones involving natural treatment processes, a study on efficiency of integrated stabilization pond (ISP) was conducted in Shoosh Sewage Treatment Plant during 1999.Materials and Methods: This ISP experimental study was conducted during three seasons with two types of raw sewage feedings. The system consists of an anerobic pond in combination with facultative pond in series with a high rate and a maturation samples from inflow and effluent were taken on weekly basis and COD, BaDS, TSS, total nitrogen, and Total phosphorous were checked, the resulting reduction in mentioned parameters formed the basis of a statistical evaluation.Results: Pollutants reduction eas higher in Spring compared with summer and fall. BaDS with 89% reduction showed the highest and total phosphorous with 60% showed the lowest reduction levels during the said period. The level of sewage pollutant reduction during three satges of the  study shows that the anerobic pond in combination with facultative pond register the highest percentage of pollutant removalConclusions: ISP systems are effective in treatment of sewage. Up flow of sewage in fermentation pit has a positive effect on the systems efficiency, and shows the fermentation pits considerable role in facultative ponds. Since there is little available experience about ISP in Iran, more investigation on the subject is recommended.

Due to territorial condition and available land in Iran cities, Stabilization Ponds are one of the best choices for wastewater treatment. Studies whole the world indicates that treated water from a well design pond is more reliable than other systems. The other point for accepting this system is related to low cost of installation and operation. The present study is about Khomein city of stabilization ponds by investigating an interference study of any analysis- ….. Samples are taken from row wastewater and effluent of ponds and wastewater treatment system by random. Tests of numbering of Colifourms and Nematods which are include PH, BOD5, COD, TSS, TDS, TS, DO have done. Correlation and Variance medium is used for analyzing of data. Results designed by Matlab and Excel graph. For chemical-physics and Coliform and Nematods tests 366 samples are taken. This study shows that there is a meaningful relation between temperature and surface load and retention time in removal of BOD, COD, COLIFORMS. (pvalu>0.05). Speed wind, evaporation, sunny days and rainy days in statistic analysis shows that stabilization pond in Khomein which are used in cold weather extremely impressed of natural parameters. Comparison of effluent result with standards shows that effluent water is usable for irrigation of parks

Surfactants are organic chemicals with wide applications as detergents. Linear alkyl benzene sulfonate (LAS) is an anionic surfactant most commonly used. Discharge of raw or treated wastewater containing this chemical into the environment causes major public health problems. In this study, 64 samples were taken from the effluent of Yazd Wastewater Treatment Plant over a period of one year. The samples were analyzed according to standard methods. The results obtained from the samples taken in different seasons showed that the highest efficiency of anionic surfactant removal was achieved in the summer in the secondary facultative stabilization pond. The least efficiency was observed in the autumn in samples from the anaerobic stabilization pond. It was also found that treated wastewater discharged into surface waters, reused for agricultural irrigation, or discharged into absorbent wells had significant differences with Pvalue<0.5 and contained surfactant contents higher than those recommended by environmental standards in all cases.

Phenol is a highly toxic aromatic compound discharged into the environment through industrial effluents. The natural biological treatment process has been widely used as one of the most feasible, eco-friendly, and cost-effective options for the treatment of pollutants such as phenol. The objective of the present experimental-analytical study was to evaluate the performance of the facultative stabilization pond in removing phenol and other organic compounds from oil refinery effluents. For the purposes of this study, a pilot-scale anaerobic stabilization pond 1.2´0.6´0.55 m in size was constructed of fiberglass sheets 6 mm in thickness. The experiment was run with a hydraulic retention time of 10 days and a hydraulic loading rate of 43.5 l/d. The organic loading rate for the facultative pond was 150 kg/h. day. Samples were taken after pond operation and seeding when the pond reached its biological stability. Depending on phenol removal levels in the anaerobic stabilization pond, initial phenol concentrations at the inlet to the facultative pond were assumed to be 0-28, 30-80, 90-130, and 150-200 under warm conditions and 100-140, and 200b-260 mg/l in cool conditions. For each sample, the parameters NH3, PO4, and Phenol were measured using the Varian spectrophotometer (model UV-120-02) at the wavelengths of 425, 690, 500 nm, respectively. TCOD, SCOD, TBOD, SBOD, pH, and ORP were also measured according to the standard methods of water and wastewater. The results showed that phenol removal efficiency of the facultative pond was 71.8% for warm temperatures and 14.66% for cool temperatures. It was also found that temperature and phenol concentration significantly affected the performance of the pond. Moreover, its performance was observed to enhance with reducing phenol concentration and increasing temperature (p<0.001). Maximum phenol removal efficiency of the system was recorded at 71.8% for warm temperatures and a low phenol concentration of 0–28 mg/l while its minimum of 14.66% was recorded at a high phenol concentration of 200-260 mg/l under cold weather conditions. Based on the results obtained, it may be concluded that the pilot-scale facultative pond has a high performance in removing organic compounds with different concentrations of phenol under warm weather conditions.

One of the indexes of stabilization pond is the presence of coliform bacteria in water and wastewater. This study aimed to determine the effect of solar light on coliform variations in stabilization pond. In this experimental study, the effect of light, pH (<7, 7. 1– 8, 8. 1– 9), and temperature (10 º C and 30 º C) on facultative stabilization pond was studied for six months. The sampling was accomplished weekly. Coliform colonies were measured using the nine tube fermentation method. The coliform deterioration constant was calculated using the Maraise model. The data were analyzed using SPSS version 20. The effect of light on coliform deterioration constant was negative. Also, low pH increased the coliform death. No significant statistical difference was seen at 10 º C and 30 º C (P < 0. 05). Low temperature cannot be adherence for facultative stabilization pond. Regarding the positive effect of temperature on the coliform death, use of facultative stabilization pond in a warm climate is suggested.

Background and Objectives: Phenol is one of the aromatic compounds, which due to its high toxicity and its presence in the industrial effluents, should be removed and prevented it, to the receiving water resources. The natural biological plant has been accepted as one of the most feasible, eco-friendly and cost-effective options for the treatment of pollutants such as Phenol. The aim of this study is efficiency evaluation of the anaerobic stabilization pond performance in removing phenol and other organic compounds from Kermanshah oil refinery wastewater.Materials and Methods: The method of study was experimental and analytical, a laboratory scale anaerobic stabilization pond, with dimensions of 1 ´1´0.2 m, using fiberglass sheet with a thickness of 6 mm was designed and built up. In this study The hydraulic retention time and hydraulic loading rate were expected 2 days and 95 liters per day respectively. Organic loading rate for anaerobic pond was 100 g/m3. After starting, seeding and biological stability, samples were taken. Initial phenol concentration was added about of 100 mg/l to pilot input, then the parameters such as NH3, PO4 and Phenol were measured by Varian spectrophotometer model UV-120-02 in the wavelength 425, 690, 500 nm respectively. TCOD, SCOD, TBOD, SBOD, pH and ORP were measured according to the standard methods of water and wastewater.Results: The results showed that the removal efficiency of NH3, PO4, phenol, TCOD, SCOD, TBOD, SBOD in the anaerobic pond were obtained 91.51%, 64.34%, 89.82% 74.99 % 73.34% 71.75%, 68.9% respectively.Conclusion: The results showed that the ability for phenol and other organic compounds removal in anaerobic pond using petroleum refinery wastewater is higher than the other systems which are expensive and complex.

Background and Aim: In clinical practice it is commonly assumed that occlusal splints have therapeutic value in the treatment of temporomandibular disorders (TMD), however there is still lack of sufficient evidence to support this claim. The purpose of this double-blind study was to evaluate the short-term (8-week) efficacy of a stabilization splint in subjects with temporomandibular disorders seeking treatment.Materials and Methods: Seventeen TMD patients were treated with stabilization splints for eight weeks. In addition to filling out questionnaires, all patients underwent a preoperative and postoperative clinical-functional investigation of the masticatory system. Qualitative data were analyzed using Fisher exact and Chi-square tests and Wilcoxon signed ranks test was applied to report quantitative data.Results: A statistically significant decrease was observed postoperatively in the Helkimo clinical dysfunction index (P=0.000) as well as the anamnestic dysfunction index (P=0.020). In addition there was a statistically significant decrease in muscle tenderness, after treatment (P=.002).Conclusion: The results of this study indicate that the use of a stabilization splint is beneficial in treatment of the signs and symptoms of TMD, and especially has a positive effect on muscle tenderness.