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三峡库区典型流域水华暴发评价函数模型研究 总被引:1,自引:1,他引:0
藻类在光照充足时将无机磷酸和ADP转化为ATP以储备能量,外部条件改变时,则ATP可逆转换为ADP以释放能量.在此理论框架下根据三峡库区典型流域水华暴发时的现场监测数据研究了绿藻光合磷酸化的活化能ΔE、计算了库区流域中若干水系在不同水文条件下提供的有效能量Δe和综合营养指数TLI(Σ),并以ΔE、Δe和TLI(Σ)为参数构建了预测和判断不同水域环境中水华是否暴发的水华暴发评价函数F,在考虑外部因素和内部因素对水华暴发影响程度的大量计算和分析的基础上,确定了ΔE、Δe和TLI(Σ)的相关权重分别为a1=0.3,a2=0.3,a3=0.4.模型计算和实地验证表明:F比单纯的TLI(Σ)作为水华暴发或者水体富营养化的判据更合理,更有说服力和更具普适性. 相似文献
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研究在低水温条件下,进厂污水中有机物浓度较低时(污水平均BOD5为45 mg/L左右),漳扎污水处理厂生化系统较优的运行工况。研究结果表明,在上述情况下,较优的连续运行工况为:污泥回流比为75%左右,MLSS为3 200~3 500 mg/L,生化池处的溶解氧在0.7~1.3 mg/L之间;较优的间歇运行工况为:以曝气3 h停曝3 h的方式运行,生化池处的溶解氧在3~5 mg/L之间,污泥回流比为75%左右,MLSS为3 200~3 500 mg/L。上述两种运行工况对污水中的污染物质都有较高的去除率,能成功避免污泥解絮的发生,使系统中的微生物平稳过冬;其中间歇曝气方式能达到节能减耗的目的,建议在旅游淡季时采用该方式运行。 相似文献
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Mohsen Mohammadi Mogharreb Morteza Goldani Bagher Emadi 《International Journal of Sustainable Engineering》2014,7(3):245-252
The underground temperature at a depth of about 3–4 m is almost constant all the year round. In summer, the underground temperature is lower than the ambient temperature, but in winter it is vice versa. This potentiality is considered for greenhouse cooling and heating by using an earth-to-air heat exchanger (EAHE). This paper considers the effects of two parameters as independent variables including the area of greenhouse and the percentage of vegetation coverage inside the greenhouse on the performance of an EAHE system during both cooling and heating modes. The inside temperature, the thermal energy exchange and the coefficient of performance (COP) of the system were considered as dependent variables. The results showed that both greenhouse area and the percentage of vegetation coverage inside the greenhouse had significant effects on the performance of the EAHE system during both cooling and heating modes. However, the COP of the EAHE system was higher in the cooling mode (4.32) than during the heating mode (1.01). The percentage of vegetation coverage negatively affected the performance of the EAHE system in the cooling mode. However, the performance of the EAHE system improved with the increase in the percentage of vegetation coverage during the heating mode. 相似文献
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Ting-Long Pan Hong-Shu Wan Zhi-Cheng Ji 《International Journal of Sustainable Engineering》2014,7(2):103-110
This paper presents a stand-alone wind power system with battery/supercapacitor hybrid energy storage. A stand-alone wind power system mainly consists of a wind turbine, a permanent magnet synchronous generator, hybrid energy storage devices based on a vanadium redox flow battery and a supercapacitor, an AC/DC converter, two bidirectional DC/DC converters, a DC/AC converter and a variable load. Several control strategies for the stand-alone wind power system are involved such as a maximum power point tracking (MPPT) control, a vanadium redox flow battery charge/discharge control and a supercapacitor charge/discharge control. The proposed MPPT control combines a sliding mode control with an extreme search control to capture maximum wind energy. This strategy avoids the necessity of measuring wind velocity, obtaining models or parameters of the wind turbine and calculating the differentials of the power generated from the wind power system and from the speed of the generator. The battery charge/discharge control maintains a constant DC bus voltage. When the battery charging/discharging current reaches the setting threshold, the charge/discharge control of the supercapacitor is triggered to limit the charging/discharging current of the battery. The simulation results show that the proposed method can rapidly respond to variations in wind velocity and load power. 相似文献
78.
Athanasios A. Rentizelas Athanasios I. Tolis Ilias P. Tatsiopoulos 《Waste management (New York, N.Y.)》2014,34(1):36-48
Municipal Solid Waste (MSW) disposal has been a controversial issue in many countries over the past years, due to disagreement among the various stakeholders on the waste management policies and technologies to be adopted. One of the ways of treating/disposing MSW is energy recovery, as waste is considered to contain a considerable amount of bio-waste and therefore can lead to renewable energy production. The overall efficiency can be very high in the cases of co-generation or tri-generation. In this paper a model is presented, aiming to support decision makers in issues relating to Municipal Solid Waste energy recovery. The idea of using more fuel sources, including MSW and agricultural residue biomass that may exist in a rural area, is explored. The model aims at optimizing the system specifications, such as the capacity of the base-load Waste-to-Energy facility, the capacity of the peak-load biomass boiler and the location of the facility. Furthermore, it defines the quantity of each potential fuel source that should be used annually, in order to maximize the financial yield of the investment. The results of an energy tri-generation case study application at a rural area of Greece, using mixed MSW and biomass, indicate positive financial yield of investment. In addition, a sensitivity analysis is performed on the effect of the most important parameters of the model on the optimum solution, pinpointing the parameters of interest rate, investment cost and heating oil price, as those requiring the attention of the decision makers. Finally, the sensitivity analysis is enhanced by a stochastic analysis to determine the effect of the volatility of parameters on the robustness of the model and the solution obtained. 相似文献
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在化学反应设计中反应动力学是较重要的因素。为得到更合理的污泥热解动力学参数计算方法,利用热重分析仪,在氮气气氛下对罐底含油污泥的热解特性进行研究。根据热重实验数据,分别采用Coats-Redfern法、Kissinger法、FWO法和Popescu法计算污泥热解动力学参数,并获取罐底泥热解制油的主要阶段(第2阶段)的反应活化能E、频率因子A并分析各种方法反应机理。通过对比不同计算方法得到动力学参数及拟合曲线与实验曲线的相关性,确定了最佳罐底含油污泥热解动力学参数计算方法。研究表明,Popescu法得到罐底泥的热解过程符合Jander方程,活化能E为101.43 kJ/mol,与FWO法得到的91.20 kJ/mol相近,且预测曲线与实验曲线有较好的相关性(0.9816),说明Popescu法计算罐底泥热解动力学参数更合适。 相似文献
80.
Renewable inequity? Women's employment in clean energy in industrialized,emerging and developing economies 下载免费PDF全文
Bipasha Baruah 《Natural resources forum》2017,41(1):18-29
Women are globally underrepresented in the energy industry. This paper reviews existing academic and practitioner literature on women's employment in renewable energy in industrialized nations, emerging economies and developing countries. It highlights similarities and differences in occupational patterns in women's employment in renewables in different parts of the world, and makes recommendations for optimizing women's participation. Findings reveal the need for broader socially‐progressive policies and shifts in societal attitudes about gender roles, in order for women to benefit optimally from employment in renewables. In some industrialized countries, restructuring paid employment in innovative ways while unlinking social protection from employment status has been suggested as a way to balance gender equity with economic security and environmental protection. However, without more transformative social changes in gender relations, such strategies may simply reinforce rather than subvert existing gender inequities both in paid employment and in unpaid domestic labor. Grounded interventions to promote gender equality in renewable energy employment – especially within the context of increasing access to energy services for underserved communities – are more prevalent and better‐established in some non‐OECD (Organisation for Economic Co‐operation and Development) countries. OECD countries might be well‐advised to try to implement certain programs and policies that are already in place in some emerging economies. 相似文献