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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Advances in Environmental Health Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Dissolved oxygen,Biological wastewater treatment,Air Nanobubbles,Excess Sludge
- چکیده:
- چکیده انگلیسی: Low efficiency of conventional aeration techniques and the excessive production and disposal of sludge are great concerns in biological wastewater treatment systems. The present study aimed to evaluate the active sludge method using batch reactors under continuous operation to determine the efficiency of aeration and sludge production through microbubble and nanobubble aeration. The results indicated that compared to microbubble aeration, nanobubble aeration increased the concentration of dissolved oxygen in the mixed liqueur of the reactor (from 2 to 4.5 mg/l), while reducing the production of excess sludge from 100 to 40 ml/g (SRT: 15-40 d). With the same SRT duration, these values were within the range of 160-70 ml/g using fine-bubble aeration. According to the results, nanobubble aeration could increase the efficiency of aeration, thereby increasing the capacity of the treatment plant and reducing the costs of biological wastewater treatment.
- انتشار مقاله: 21-03-1397
- نویسندگان: Mehrdad Ahmadi,Gholamreza Nabi Bidhendi,Ali Torabian,Nasser Mehrdadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Advances in Environmental Health Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Dissolved oxygen,Biological wastewater treatment,Air Nanobubbles,Excess Sludge
- چکیده:
- چکیده انگلیسی: Low efficiency of conventional aeration techniques and the excessive production and disposal of sludge are great concerns in biological wastewater treatment systems. The present study aimed to evaluate the active sludge method using batch reactors under continuous operation to determine the efficiency of aeration and sludge production through microbubble and nanobubble aeration. The results indicated that compared to microbubble aeration, nanobubble aeration increased the concentration of dissolved oxygen in the mixed liqueur of the reactor (from 2 to 4.5 mg/l), while reducing the production of excess sludge from 100 to 40 ml/g (SRT: 15-40 d). With the same SRT duration, these values were within the range of 160-70 ml/g using fine-bubble aeration. According to the results, nanobubble aeration could increase the efficiency of aeration, thereby increasing the capacity of the treatment plant and reducing the costs of biological wastewater treatment.
- انتشار مقاله: 21-03-1397
- نویسندگان: Mehrdad Ahmadi,Gholamreza Nabi Bidhendi,Ali Torabian,Nasser Mehrdadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Applied Biotechnology Reports
- نوع مقاله: Journal Article
- کلمات کلیدی: Membrane bioreactor,Membrane fouling,Activated Sludge,Pulp and Paper Wastewater
- چکیده:
- چکیده انگلیسی: The pulp and paper wastewater contains various organic and inorganic compounds in considerable amounts. Membrane bioreactor (MBR) technology has been used extensively for various industrial wastewater treatments due to its ability to produce appropriate effluent according to water quality regulations. Pulp and paper wastewater can be successfully treated by MBR in different conditions according to the wastewater and MBR characteristics. However, a major drawback in the use of MBR is membrane fouling, which leads to the reduction of effluent permeate flux. Fouling factors need to be considered because they are the major problems affecting the MBR performance. Besides, the performance of MBR can be increased by wastewater pretreatment methods and addition of a fouling reducer. In this paper, the application of aerobic and anaerobic MBR for pulp and paper wastewater treatment and membrane fouling has been reviewed. It has been found that the advantages of MBR over conventional biological treatment processes have made this technology popular for pulp and paper wastewater treatment.
- انتشار مقاله: 30-04-1397
- نویسندگان: Ali Izadi,Morteza Hosseini,Ghasem Najafpour Darzi,Gholamreza Nabi Bidhendi,Farshid Pajoum Shariati,Mohammad Reza Mosaddeghi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Membrane fouling,Organic matter,Paper-recycling wastewater,hybrid airlift membrane bioreactor (HAMBR)
- چکیده:
- چکیده انگلیسی: In this study, a novel integrated Hybrid Airlift Membrane Bioreactor (HAMBR) composed of oxic, anoxic, and anaerobic zones was developed to simultaneously remove organic matter and nitrogen from real paper-recycling wastewater. The removal efficiencies of Chemical Oxygen Demand (COD), ammonium, nitrite, nitrate and Total Nitrogen (TN) for permeate and supernatant were in the range of 88-99%, 54-83%, 70-90%, 65-95% and 61-90%, respectively. In addition, the membrane fouling was evaluated by Trans-Membrane Pressure (TMP) monitoring during the experimental period at a constant flux of 12 L/m2h,and the rate of TMP increase was 1.75 mbar/day. The results showed that the hybrid airlift membrane bioreactor can be applied effectively to the simultaneous removal of organic and nutrient from real wastewater and the performance of the membrane bioreactor was satisfactory in terms of resistance against membrane fouling phenomenon, which is an important parameter during HAMBR operation.
- انتشار مقاله: 27-08-1397
- نویسندگان: Ali Izadi,Morteza Hosseini,Farshid Pajoum Shariati,Ghasem Najafpour Darzi,Gholamreza Nabi Bidhendi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Phytoremediation,Flax,Hydrocarbon-polluted soil,Burningbush
- چکیده:
- چکیده انگلیسی: Phytoremediation is an emerging environmental-friendly technology that can be a promising solution to remediate oil-polluted soils. The impact of high amount of hydrocarbons on growth characteristics of burningbushand common flax was evaluated in this survey. The influence of organic fertilizers was also assessed on growth of plant species in oil-contaminated soil. Soil samples in which plants showed the best growth were analyzed for residual total petroleum hydrocarbons (TPHs) by GC-FID. Burningbush was employed for the first time in the history of phytoremediation of oil-polluted soils in this research. The two studied plant species demonstrated promising remediation efficiency in highly contaminated soil; however, petroleum hydrocarbon contamination depressed growth of surveyed plants significantly. Utilization of peat fertilizer improved plants’ growth parameters in highly oil-contaminated soil. Flax and burning bush reduced TPHs levels in contaminated soil by 87.63 and 65.29 percent, respectively, in comparison to initial concentration.
- انتشار مقاله: 02-03-1387
- نویسندگان: Ravanbakhsh Shirdam,Ali Daryabeigi Zand,Gholamreza Nabi Bidhendi,Nasser Mehrdadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Ozone,reactor,sludge reduction,Oxidation of sludge,Yield coefficient
- چکیده:
- چکیده انگلیسی: The excessive biological sludge production is one of the disadvantages of aerobic process such as SBR. So the problem of excess sludge production along with its treatment , and disposal in aerobic processes in municipal and industrial waste water can be seen in many parts of the world even in our country . to solve the problem of excess sludge production , reducing in by oxidizing some of the sludge by Ozone is a suitable idea , thus reducing the biomass coefficient as well as the sewage sludge disposal. In this study, Two SBR reactors with of 20 liter being controlled by on-line system are used. After providing the steady state in the reactors, along the 8 month research sampling and testing parameters such as COD, MLSS, MLVSS, DO, SOUR, SVI, residual ozone and Yield coefficient were done. The results showed that during the solid retention time of 10 days the kinetic coefficient of Y and Kd was 0.58 (mg Biomass / mg COD) and 0.058 (1/day) respectively. At the next stage of research, different concentrations of ozone in one liter of the returned sludge to reactor were used to reduced the excess biological sludge production. The results showed that the 20 mg ozone per gram of MLSS in one liter of the returned sludge to reactor is able to reduce Yield coefficient from 0.58 to 0. 28 (mg Biomass/mg COD),In other words, the biological excess sludge by 52 % .but the soluble COD increased slightly in the effluent and the removal percentage decreased from 92 in blank reactor to 64 in test reactor. While the amount of SVI and SOUR in this consumed ozone concentration reduced 9 mgO2/h.gVSS and 20 ml/g respectively. No sludge was seen in the 25 mg ozone concentration per gram of MLSS in one liter of the returned sludge to reactor.
- انتشار مقاله: 01-05-1387
- نویسندگان: Afshin Takdastan,Naser Mehrdadi,Ali Akbar Azimi,Ali Torabian,Gholamreza Nabi Bidhendi
- مشاهده
- جایگاه : پژوهشی
- مجله: Environmental Energy and Economic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: earthquake,crisis management,Socio-Psychological Vulnerability,Bam City,Theme Method
- چکیده:
- چکیده انگلیسی: Natural disasters in various forms have been identified as destructive phenomena during the life of earth planet and are also a serious threat to the inhabitants of the planet. Therefore, this issue leaded to the formation of a process called crisis management which includes activities occurring before, within and after the event to reduce the vulnerability. The country of Iran is considered as one of the world's affected countries from natural disasters due to its geographical location and climate diversity. In this research, the role of crisis management in reducing the socio-psychological vulnerability of affected citizens in 2003 earthquake of Bam city was investigated. Library and field study methods have been used to collect information in this study. Also, a qualitative-quantitative method was used to analyze the data by employing the theme method and consequently the most important factors affecting the citizen's socio-psychological vulnerabilities of Bam city after the earthquake were identified.
- انتشار مقاله: 23-05-1397
- نویسندگان: Seyed Rasoul Mousavi,Hamid Rashedi,Gholamreza Nabi Bidhendi
- مشاهده
- جایگاه : پژوهشی
- مجله: Environmental Energy and Economic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Minimization,Water pinch method,Flow intensity,Input and output concentrations,Water Consumption
- چکیده:
- چکیده انگلیسی: Since less than 1 percent of world waters are potable, minimizing water consumption is a significant issue. The aim of this study is to present a suitable algorithm for optimization of water consumption in water pinch analysis. In this regard, the results of computer algorithm are verified by the results of previous studies. As a case study, dissolved solid pollutants are taken into consideration. The results indicated that using a water pinch method decreased the amount of this pollutant up to 8.5% in potable water in comparison with raw water. Moreover, by assuming a unit with ten operations in parametric studies, it is observed that with changing one of the influential factors without any change in other parameters, the effects of output concentration changes will be more than flow and input concentration changes. The results of this research can be used functionally in refineries and all the water consumption centers.
- انتشار مقاله: 13-06-1397
- نویسندگان: Gholamreza Nabi Bidhendi,Arezoo Shafikhani
- مشاهده
- جایگاه : پژوهشی
- مجله: Environmental Energy and Economic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Life cycle assessment,Sewage Sludge Disposal,Ekbatan Tehran Wastewater Treatment,OpenLCA,Eco Indicator 99
- چکیده:
- چکیده انگلیسی: The present study has assessed the life-cycle as an efficient method for environmental analysis, four disposal systems, and the management of urban sewage sludge in Ekbatan Tehran wastewater treatment plant. In order to assess the effects of the life-cycle Eco Indicator 99 method was used by OPENLCA software, and system boundary has been considered since the arrival of swage to wastewater treatment until its exit and the disposal of sludge. According to the results, using sludge in agricultural lands has positively influenced the group effect of fossil fuels due to economizing the production of phosphor and nitrogen fertilizers. On the other hand, using sludge in agriculture has negatively influenced the carcinogenetic group effects, Inorganics Respiratory, ecotoxicity, acidification, and fertilization, which is mainly due to the heavy metals in sludge. However, industrial fertilizers have some heavy metals. Therefore, comparing the effects of life cycle from two processes of using sludge and industrial fertilizer may be considered in decision making to select the optimal process.
- انتشار مقاله: 13-04-1399
- نویسندگان: Gholamreza Nabi Bidhendi,Morteza Rahmanzedeh,Hasan Hoveidi,Naser Mehrdadi
- مشاهده