Compatibility of Different Eucalyptus Species and Provenances Under Sewage Irrigation Using Yazd City Wastewater Treatment Plant Effluent

Different eucalypt species have various utilizations, therefore eucalypt species trials is essential for different ecological conditions. For this reason an eucalypt species and provenances trial was conducted at Yazd City Wastewater Treatment Plant, using industrial and domestic sewage under the randomizes complete blocks statistical design with four replicates and eight treatments at 3 x 3 m. spacing and 36 seedlings in each plot. The treatments consisted of: E. rubida (166-sh), E. saligna  ig. botryoides (20762), E. saligna (171-sh), E. macarthurii (169-sh), E. viminalis (15211), E. sargentii, E. camaldulensis (41-zh), and E. microtheca. The results showed that after  the first year of planting there were significant differences between the treatments (P< 0.01) in respect to survival, height, diameter and crown parameters. The greatest survival after the first and second years of planting belonged to E. camaldulensis (41-zh), E. sargentii and E. microtheca(98.6%, 95.1%, 92.4% and 98.6%, 95.1%, 94.4%, respectively). The species E. camaldulensis (41-zh) had the best performance after the first and the second years of planting, although there was not significant difference between some of the eucalypt characteristics. Overall, the species E. camaldulensis (41-zh) can be recommended for forest plantation and wood production at sites similar to the trial condition, ecologically. The species E. rubida, E. saligna and E. viminalis are also recommended for plantation and wood production, using sewage irrigation, due to their fast growing performance, although they might have high mortality at their first stage of establishment. E. sargentii is a suitable species for desertification control due to its high resistance to soil and water salinity and somewhat coldness and its fast diameter and crown growth

The Efficiency of Typha Latifolica in Subsurface Flow Constructed Wetland for Wastewater Treatment

Background: Natural methods of wastewater treatment, such as wetlands, are simple, cheap and acceptable for developing countries, especially small and remote cities. The aim of this study was to evaluate the efficiency of Typha Latifolica in subsurface flow constructed wetland for wastewater treatment. Methods: In this experimental research, the efficiency of Typha Latifolica in subsurface flow wetland for removing chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total suspended solids (TSS), nitrate-N (NO3-N), ammonia-N (NH3-N), orthophosphate (PO4-P), total coliform and fecal coliform was evaluated in Yazd, Iran. Two reactors (without the plant and with plant) were made, as pilot study, by subsurface flow constructed wetland with the dimensions of 2 × 1.5 × 0.6 m and with a retention time of 4 days. In two months, samples were taken from the incoming and outgoing flow of the reactors and were analyzed according to standard methods. Results: The efficiency of Typha Latifolica wetland for removing COD, BOD5, TSS, NO3-N, NH3-N, PO4-P, total coliform and fecal coliform was 72, 72, 85, 31, 25, 40, 94 and 59 percent, respectively, via 44, 34, 77, 15, 0.3, 1, 17 and 29 percent for the control weland, respectively; all the differences were statistically significant, except for NH3-N and fecal coliform. Conclusion: According to the result of this study, Typha Latifolica has a high efficiency in removing organic material and suspended solids; the treated wastewater by Typha Latifolica can achieve the environmental standards for agriculture and irrigation use. Keywords: Subsurface flow constructed wetland, Typha Latifolica, Wastewater treatmen

Removal Efficiency of Nitrogen, Phosphorus and Heavy Metal by Intermittent Cycle Extended Aeration System from Municipal Wastewater (Yazd-ICEAS)

Introduction: Sequential batch reactor (SBR) is one of the modified biological treatment systems which is able to remove BOD5, Nitrogen, and phosphorus from wastewater. The object of this study is to determine the removal efficiency of nitrogen, phosphorus, and heavy metals from municipal wastewater by the advanced SBR system. Materials and Methods: This descriptive-analytical and cross-sectional study was conducted on advanced SBR in Yazd city wastewater treatment plant during a one-year period (from September, 2014 until August, 2015). The samples were collected from the influent and effluent of the advanced SBR as a composite in order to measure BOD5, TKN, NH4+, TP parameters, and heavy metals monthly. Also, statistical t-test was used to compare heavy metals quantities with standard ones. Results: The results showed that the mean of removal efficiency of BOD5, TKN, NH4+, and TP were 92.24, 80.36, 90.41, and 66.41 percent, respectively. Also, the removal efficiency of Iron (Fe), Plum bum (Pb), Nickel (Ni), Zink (Zn), Chromium (Cr), and Cadmium (Cd) were 47.77 %, 40.71 %, 24.79 %, 12.29 %, 5.70 % and 5.65 %, respectively. Conclusion: The high removal efficiency of BOD5, TKN, and NH4+ showed that this advanced SBR system had an appropriate efficiency for nitrification. Phosphorus removal (TP) had a lower efficiency than those of NH4+ and TKN, but it was within the environmental standard limits. On the other hand, in the advanced SBR the removal efficiency of heavy metals for Cd was not within the standard limits

Evaluation the Correlation between Turbidity and Total Suspended Solids with other Chemical Parameters in Yazd Wastewater Treatment Effluent Plant

Introduction: Expensive chemical tests are usually applied to control the efficiency of wastewater treatment plants. However, the cost of measuring these parameters is one of the challenges of the wastewater treatment plants. Using statistical methods has been evaluated for possibility of calculating expensive parameters by measuring the inexpensive parameters in this study. Materials and Methods: Initial sample number in this study was 87 cases that were collected from SBR effluent treatment plants of Yazd as a routine sampling for two years in March 2013 to March 2015. Total suspended solids (TSS) and turbidity parameters were defined as independent variables and twelve parameters including BOD5, COD, TKN, NH3+, NO3-, NO2-, TP, TH, Ca2+, Mn2+, alkalinity, and color were the dependent variables. Spearman test was used to investigate the significant relationship between independent and dependent variables. Linear regression analysis was used to determine the linear equation between TSS and turbidity as independent variables with BOD5, COD, TKN, NH3-, NO2-, TP and color as dependent variables. Results: The results of the regression equations in relation to turbidity and TSS with independent variables showed that the R value for color, TKN, NH3+, BOD5, COD, TP, and NO2- were 0.942 , 0.931 , 0.91 , 0.905 , 0.874 , 0. 872 and 0.86 respectively from the highest to the lowest. Conclusion: The measured values of BOD5, COD, TKN, TP, NO2-, NH3+, and color in laboratory were very close to those predicted through regression equations. Therefore, regression equations created in this study can be used to calculate expensive parameters

Performance evaluation of wastewater stabilization ponds in Yazd-Iran

Background: Yazd waste stabilization pond facilities consist of three stabilization pond systems, module 1, module 2 and module 3 that AWSP module 1 has started its operation. The existing facilities have had several problems in their operation. The objectives of this research were to evaluate the performance of stabilization ponds in wastewater treatment of the city of Yazd, due to several problems in their operation, and to prepare a scheme of its upgrading, if necessary. Methods: During the period from December to June 2010, data analysis were carried out for both raw and treated wastewater. Results: Results of these investigations showed that the average effluent concentrations of Biochemical Oxygen Demand 5 (BOD5), Chemical Oxygen Demand (COD) and Suspended Solid (SS) taken from anaerobic pond and secondary facultative ponds of module 1 were 306.9, 135.18, 139.75 and 136.75, 69.025, 136.5 mg/L, respectively. Conclusion: These results indicated that the effluent of the anaerobic pond of module 1 was complied with the Iranian treated wastewater standards for agricultural reuse in terms of BOD5 and COD concentrations; hence the secondary facultative ponds could be changed to other primary facultative ponds in order to increase the capacity of wastewater treatment plant

Comparing the Efficiency of Stabilization Ponds and Subsurface Constructed Wetland in Domestic Sewage Treatment in City of Yazd

Wastewater is one of the most important contributors to water pollution on the one hand, while it has the potential to serve as an alternative source of water if subjected to proper treatment, on the other. The present study was designed to compare the removal efficiencies of stabilization ponds and subsurface constructed wetlands in the treatment of urban wastewater in Yazd. For this purpose, 72 samples were collected at the inlet and outlet of a constructed wetland as well as 72 from the inlet and outlet of stabilization ponds over a period of one year. The samples were subjected to identical tests and the results were compared. The removal efficiencies for BOD5, COD, TSS, NH4-N, NO3-N, and PO4 in the stabilization ponds were 79.7, 79.6, 44.4, 57, 0, and 42.5 percent, respectively. The same parameters for the constructed wetland system were 80.7, 81.5, 77.7, 9.9, 34, and 59.4, respectively. Moreover, BOD5, COD, TSS, and PO4 removal efficiencies were higher in autumn and summer. From these results, it may be concluded that constructed wetlands are more commercially viable than stabilization ponds both in terms of performance and cost-effectiveness

Removal Efficiency of Linear Alkyl Benzene Sulfonate (LAS) in Yazd Stabilization Pond

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 Pvalu