| As water consumption increases sharply, many areas face water shortage now or in the near future. In order to overcome this crisis, a number of measures have been introduced for the effective use of this valuable natural resource. In this situation, wastewater could be considered as a water resource. However, the conventional treatment systems have focused on disposal rather than reuse. Thus the related issues of what kind of wastewater should be treated, how to treat and how to transport them should be studied.City sewage infrastructure of high input, high urban wastewater treatment plant operating costs, the net leakage cause secondary pollution and lack of water resources reuse of sewage in the demand, there is an urgent need for stable operation, low power consumption sewage treatment process. In this study, SBR technology and artificial wetlands technology combination for domestic wastewater treatment in order to get the best working conditions of combination treatment domestic sewage and the optimal economic operating parameters to give full play for constructed wetland performance and SBR system to reduce energy consumption.In the composition process constructed wetlands is a natural process, we setting aeration natural trough in constructed wetland in order to improve the dissolved oxygen within constructed wetland so not need energy for this process. The Sequencing Batch Reactor (SBR) is the name given to a wastewater treatment system based on activated sludge and operated in a fill-and-draw cycle. The most important difference between SBR and the conventional activated sludge systems is that reaction and settle take place in the same reactor. Activated sludge in the SBR need dissolved oxygen and must maintain a certain level of activated sludge concentration, SBR system aeration intensity and aeration time have a big impact in the combination process and energy consumption.At ambient normal temperature conditions T≥15oC, the SBR system running three cycles per day, the volume of wastewater treating is equal to 1.5m3/day, constructed wetland and hydraulic retention time approximately is equal to one day. The SBR system is running four operation cyclic modes (first, second, third and fourth) and aeration time reduced from 5 to 2 hours, at the same time adopt restrictions aeration, SBR system will be controlled low dissolved oxygen state DO in the range (0.5-1) mg/L, in this condition we do (COD, Ammonia, TN and TP) tests in order to meet with "Urban Landscape Water Standards"(GB/T18921-2002).At ambient low temperature conditions T < 15oC, the SBR system running two cycles per day, the volume of wastewater treating is equal to 1m3/day, constructed wetland and hydraulic retention time approximately is equal to 1.5 day, in the condition of low temperature we do the same tests before as (COD, Ammonia, TN, TP) but the difference in this condition the standard adopted is "City of miscellaneous water standards" (GB/T18921-2002) which not required to meet with TN and TP effluents, also this condition specified by extended aeration time and cyclic modes her represented by fifth, sixth, seventh and eighth as selected operating modes.This research report's on the performance of sub-surface horizontal Constructed Wetland (CW) pilot plant in polishing effluent from the Sequencing Batch Reactor (SBR) containing activated sludge in order treat and water reuse. In this study the sequencing batch reactor received and pretreated part of the wastewater from the student's hostels at the Chongqing University at B campus in P.R. China, Chongqing is located in the Three Gorges Reservoir area.Domestic wastewater firstly inter to settling tank from student's hostel as a primary treatment to remove some pollutants that easy removed by settling operation and filter putting in the head of pipe carrier to SBR, in the SBR run eight operation cyclic modes, after this operation supernatant withdrawn by absorbent pump to constructed wetland which consisted of three S-shape cell and aeration beds to enhance dissolved oxygen for removal different pollutant that remains in the effluent from SBR.The experiment started in April 2006 to the end of March 2007, lasted one year. Test operation of the eight cycles, each cycle run 20-25 days. The primary objective of this investigation was to optimize eight operations cyclic modes of existing (SBR) to elevate the water quality of the treated sewage wastewater to the level meet with "landscape water standards" and "miscellaneous city water quality standards". Both SBR and constructed wetland treatment systems were employed for the experimental tests. Under condition of normal temperature as T≥15°C the best cyclic mode given a good results for Total Nitrogen TN is third cyclic mode because the average concentration value of TN effluent which resulted from SBR and constructed combined treatment process is equal to 14.21 mg/L can be met with "urban landscape water standards." Because these standards recommended by 15 mg/L achieving it, also the average concentration value of TN effluents (8.14 and 11.52) mg/L from first and second cyclic modes respectively which can met with this standards, but we considered two reasons first one is decreasing a power that consumed by SBR to operate pump for aeration as shown before the first and second cyclic modes is 4 and 5 hours respectively while the aeration time take 3 hours in third cyclic mode, the second reason is the effect role of constructed wetland to smooth out TN effluent that come from SBR as depicted from TN removal efficiency in first and second cyclic modes is 28.59% and 31.86% respectively while TN removal efficiency in constructed wetland was 35.12% more than before so that choose third cyclic mode as the best cyclic mode in TN removal.Under condition of normal temperature as T≥15°C the best cyclic mode given a good results for Total Phosphorus TP is third cyclic mode because the average concentration value of TP effluent which resulted from SBR and constructed combined treatment process is equal to 0.47 mg/L can be met with "urban landscape water standards" Because these standards recommended by 0.5 mg/L achieving it, also the average concentration value of TP effluents (0.27 and 0.34) mg/L from first and second cyclic modes respectively which can met with this standards, TP removal efficiency by constructed wetland is 61.95% also higher than 31.65% and 48.63% which represented first and second cyclic modes respectively, by considered two reasons explained in the preceding paragraph choose third cyclic mode as the best cyclic mode in TP removal.For ammonia removal under condition of normal temperature as T≥15°C in this case the average effluent value of ammonia is 5mg/L can achieve "urban landscape water standards". As shown from results the average ammonia effluent of combination SBR with constructed wetland in (first, second, third and fourth) cyclic modes were (2.14, 2.93, 3.54 and 4.21) mg/L respectively all these values achieve reuse standards but by considering SBR power reducing and constructed wetland impact in ammonia removal so that consider fourth cyclic mode best one met with standards this cyclic mode specified by two hour aeration this mean less power consumed by SBR and ammonia removal efficiency by constructed wetland is 57.52%.By considering COD removal under normal temperature condition as T≥15°C in this case the average effluent value of COD is 20 mg/L can achieve "urban landscape water standards". As shown from results the averages COD effluent of combination SBR with constructed wetland in (first, second, third and fourth) cyclic modes were (8, 11, 16 and 17) mg/L respectively all these effluent values can achieve reuse standards but also by considering SBR power reducing and constructed wetland impact in COD removal, so that considered fourth cyclic mode best one met with standards this cyclic mode specified by two hour aeration this mean less power consumed by SBR and ammonia removal efficiency is by constructed wetland 16.11%.As mentioned before we do optimization to chose best operation cyclic mode under normal at low dissolved oxygen, so considered third cyclic mode as the best one satisfied"urban landscape water standards"for TN, TP, ammonia and COD removals by combination SBR with constructed wetland for domestic sewage treatment processes under normal temperature condition when T≥15°C, The results showed that the removal efficiency that has been achieved by combined SBR with constructed wetland systems were (79.78%+9.93%), (52.74%+39.84%), (43.02%+35.12%) and (30.14%+61.95%) for COD, Ammonia, TN and TP respectively, third cyclic mode characterized by follow: SBR characterized by one hour (fill), three hours (aeration), one hour (settle), one hour (discharge) and two hours (idle) while constructed wetland characterized by (Hydraulic Retention Time) is 24 hours, (Hydraulic Load Rate) is 16.1cm/d and sewage treatment is 1.5m3 per day.Within low temperature condition when T < 15°C we have four operation cyclic modes also as (fifth, sixth, seventh and eighth) and the standards in this case is "City of miscellaneous water standards" which different of the standards in the case of low temperature condition and in this case just ammonia and COD satisfied "City of miscellaneous water standards" without TN and TP, so that by consider COD removal under low temperature condition the average effluent value of COD is 20mg/L can achieve "City of miscellaneous water standards" so as shown from results the average COD effluent of combination SBR with constructed wetland in (fifth, sixth, seventh and eighth) cyclic modes were (12, 19, 16 and 14)mg/L respectively all these values achieve reuse standards but by considering SBR power reducing and constructed wetland impact in COD removal, so consider sixth cyclic mode best one met with standards this cyclic mode characterized by three hour aeration after that two hour anoxic and then one hour aeration this mean less power consumed by SBR compared with (fifth, seventh and eighth) cyclic modes and COD removal efficiency by constructed wetland is 6.98%.By considering ammonia removal under low temperature condition as T < 15°C in this case the average effluent value of ammonia is 10 mg/L can achieve "City of miscellaneous water standards" as shown from results the averages ammonia effluent of combination SBR with constructed wetland in (fifth, sixth, seventh and eighth) cyclic modes were (16.33, 25.27, 14.54 and 9.14) mg/L respectively just one of these effluent values can achieve reuse standards, this one is eighth cyclic mode this cyclic mode characterized by eight hour aeration.In order to chose the best cyclic mode under low temperature condition T < 15°C as explained in the foregoing two paragraphs we choose sixth cyclic mode as best cyclic mode that achieved "City of miscellaneous water standards" (GB/T18920-2002)in the case of COD removal by combination SBR with constructed wetland treatment processes but eighth cyclic mode also can achieve that, also we choose eighth cyclic mode as best cyclic mode that satisfied "City of miscellaneous water standards" in the case of ammonia removal but in this case sixth cyclic mode couldn't achieved "City of miscellaneous water standards", so that under this reasons considered eighth cyclic mode as the best one satisfied these standards for ammonia and COD removals by combination SBR with constructed wetland for domestic treatment processes under normal temperature condition when T < 15°C, the results showed that the removal efficiency that has been achieved by combined SBR with constructed wetland systems were (68.33%+21.06%) and (92.51%+3.74%) for ammonia and COD respectively.Eighth cyclic mode characterized by follow SBR characterized by one hour (fill), eight hours (aeration), one hour (settle), one hour (discharge) and one hours (idle) while constructed wetland characterized by (Hydraulic Retention Time) is 36 hours, (Hydraulic Load Rate) is 10.7cm/d and sewage treatment is 1m3 per day.In the constructed wetland ,Cyperus alternifolius plant which planted in the second and third constructed wetland cells is not affected by seasonal changes, but aquatic Canna plant which planted in the first wetland cell is great affected by seasonal changes especially in winter season the growth was bad compared with Cyperus alternifolius plant, the plants need a three-month liquidation.Cyperus alternifolius and aquatic Canna is a good wetland plant, plant root system, the long of Cyperus alternifolius roots more than 30 centimeters, in the two plants root system contain large attachment filler. In the plant root zone due to oxygen plant roots, provide an aerobic microbial environment, biofilm formation of dense structure, a brown flocculent.The concentration of sludge is about (3000-4000) mg/L under restrictive aeration DO (0.5-1) mg/L, while in the case of school holidays within summer and winter holidays almost student leaved hostels for a period so that the influent concentration will be low and concentration of sludge be less than before is about (2000-3000) mg/L.
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