Hydrological adjustment and flooding control of wetlands in the Liaohe Delta

The function of estuary wetland on hydrological adjustment and flooding control is studied in this paper. It is estimated that the evapotranspiration in the reed field during growth season(June to October) is 722.9 mm, which is 37.5% higher than large water body(E 601∶525.9 mm). The water replacement rate in the reed field can reach 95% only when the rains continuously for 11 days and the precipitation reached 912 mm. For the water balance in the paddy field, the total water requirement ranges between 1920 and 1860 mm, among which, 31% is from precipitation, and the left is provided by reservoirs. The water usage efficiency is 0.35 at present productivity. Based on the landscape characteristics and functionalities on flooding control, 5 functional zones are designed for the Liaohe Delta: key protected area; underground storage area; flooding discharge area; flood diversion area in emergency; and flood control drainage area.

Experimental study on water-saving and emission-reduction effects of controlled drainage technology

Field experiments and laboratory analysis were carried out to determine the effects of controlled drainage（CTD） and conventional drainage（CVD） technologies on drainage volume, concentrations of NH4^＋ -N, NO3^-N, and total phosphorus（TP）, nitrogen and phosphorus losses, rice yield,and water utilization efficiency. Results show that CTD technology can effectively reduce drainage times and volume; NH4^＋ -N, NO3^-N, and TP concentrations, from the first to the fourth day after four rainstorms decreased by 28.7%e46.7%, 37.5%e47.5%, and 22.7e31.2%, respectively,with CTD. These are significantly higher rates of decrease than those observed with CVD. CTD can significantly reduce nitrogen and phosphorus losses in field drainage, compared with CVD; the reduction rates observed in this study were, respectively, 66.72%, 55.56%, and 42.81% for NH4^＋ -N, NO3^-N, and TP. Furthermore, in the CTD mode, the rice yield was cut slightly. In the CVD mode, the water production efficiencies in unit irrigation water quantity, unit field water consumption, and unit evapotranspiration were, respectively, 0.85, 0.48, and 1.22 kg/m^3, while in the CTD mode they were 2.91, 0.84, and 1.61 kg/m^3 din other words, 3.42, 1.75, and 1.32 times those of CVD. Furthermore, the results of analysis of variance（ANOVA） show that the indicators in both the CVD and CTD modes, including the concentrations of NH4^＋ -N, NO3^-N, and TP, the losses of NH4^＋ -N, NO3^-N, and TP, irrigation water quantity, and water consumption, showed extremely significant differences between the modes, but the rice yield showed no significant difference.

Effect of Rural Sewage Irrigation Regime on Water-Nitrogen Utilization and Crop Growth of Paddy Rice in Southern China

Reclaimed water irrigation has become an effective mean to alleviate the contradiction between water availability and its consumption worldwide.In this study,three types of irrigation water sources(rural sewage’s primary treated water R1 and secondary treated water R2,and river water R3)meeting the requirements of water quality for farmland irrigation were selected,and three types of irrigation water levels(low water levelW1 of 0–80 mm,medium water level W2 of 0–100 mm,and high water level W3 of 0–150 mm)were adopted to carry out research on the influence mechanismS of different irrigation water sources and water levels on water and nitrogen use and crop growth in paddy field.The water quantity indicators(irrigation times and irrigation volume),soil ammonium nitrogen(NH4+-N)and nitrate nitrogen(NO3−-N),rice yield indicators(thousand-grain weight,the number of grains per spike,and the number of effective spikes),and quality indicators(the amount of protein,amylose,vitamin C,nitrate and nitrite content)of rice were measured.The results showed that,the average irrigation volume under W3 was 2.4 and 1.9 times of that under W1 and W2,respectively.Compared with R3,the peak consumption of rice was lagged behind under R1 and R2,and the nitrogen form in 0–40 cm soil layers under rural sewage irrigation was mainly NH4+-N.The changes of NO3−-N and NH4+-N in the 0–40 cm soil layer showed the trend of declining and then increasing.The water level control only had a significant effect on the change of NO3−-N in the 60–80 cm soil layer.Both irrigation water use efficiency and crop water use efficiency were gradually reduced with the increase of field water level control.The nitrogen utilization efficiency under rural sewage irrigation was significantly higher than that under R3.Compared with the R3,rural sewage irrigation could significantly increase the yield of rice,and as the field water level rose,the effect of yield promotion was more obvious.It was noteworthy that the grain of rice under R1 monitored the low nitrate and nitrite content,but no nitrate and nitrite was discovered under R2 and R3.Therefore,reasonable rural sewage irrigation(R2)and medium water level(W2)were beneficial to improve nitrogen utilization efficiency,crop yield and crop quality promotion.

Principles and technology for stepwise utilization of resources for mitigating deep mine heat hazards

As is well known, deep mines are hot. As mining depth increases, the temperature of the surrounding rock also increases. This seriously affects mine safety and production and has restricted the exploitation of deep coal resources. Therefore, reducing the working face temperature to improve working conditions by controlling these heat hazards is an urgent problem. Considering problems in cooling deep mines both domestically and abroad along with the actual conditions of the Zhangshuanglou coal mine, we propose a HEMS technology that uses heat resources from deep mines in a stepwise manner. HEMS means a high temperature ex-change machinery system. Mine inrush-water is used as a source of cooling. Twice the energy is extracted from the mine inrush water. Heat is used for building heating in the winter and cold water is used for cooling buildings in the summer. This opens a new technology for stepwise utilization of heat energy in deep mines. Energy conservation and reduced pollution, an improved environment and sustainable economic development are realized by this technique. The economic and social effects are obvious and illustrate a good prospect for the application and extension of the method.

Floodwater utilization of the Three Gorges Project

Floods are both risks and resources. Floodwater utilization is an important part of flood management. Considering the rising shortage of water resources, serious water pollution, and undersupply of electric power, it’s imperative to strengthen flood management. In light of the hydrological characteristics of the Three Gorges Project (TGP) on the Yangtze River in P. R. China, we investigated the necessity and feasibility of TGP floodwater utilization, proprosed dynamic control of limited water level during flood season of the reservoir and basin-wide integrated floodwater management as strategies, and identified problems that might occur in practice.

Site Selection of Waste Slag Yard and Design of Protective Measures in Water Supply Project of Drawing from the Songhua River in Central Cities of Jilin

Water supply project of drawing from the Songhua River in central cities of Jilin is taken as research object.On the basis of analyzing project characteristics and natural conditions of the project area,site selection of waste slag yard of water diversion project and design of water and soil conservation measures are discussed.Rationality of site selection of waste slag yard and pertinence of prevention and control measures of water and soil loss in waste slag yard are analyzed,and comprehensive utilization of waste slag in large-scale production and construction projects is explored.

Application of Hierarchical Optimal Control Theory to Coordinative Management for Water Resources Utilization and Regional Economic Development

Water resources is used conjunctively for many purposes in Shijiazhuang region,and demands are satisfied by mining of groundwater and releases from two reservoirs.In the paper,based on the theory of multilevel hierarchical optimal control on large-scale systems,three management models are developed:(1)a stochastic two-level hierarchical management model of surface water system;(2) a linear two-level hierarchical management model of groundwater system;(3)a nonlinear two-level hierarchical mallagement model of regional economic development system.In the end, a three-level hierarchical coordination management model is formulated for water resources utilization and economic development in Shijiazhuang region.The simulation results show that the models are good in adaptability for Shijiazhuang region,and they may be used to manage the regional economic development.

基于water-level调整的认知无线电传输速率计算算法

在瑞利衰落模型下,根据认知用户的效用函数,来解决认知无线电中的信道规划问题,进而得到认知用户的传输速率。当认知用户传输功率和比特误码率受限时,其最终效用仅与water-level有关,因此文中提出了一种基于water-level调整的功率分配及算法,实现了认知无线电中载波及功率的合理分配,并得到了认知用户的传输速率.理论与仿真分析表明:该算法具有较低的运算复杂度和接近于最优算法的认知用户效用;调整因子仅与算法的收敛速度有关,而与用户总效用及信道的分配结果无关.

面向新时期新需求的三峡水库运行方案研究

本文回顾三峡水库设计洪水、特征水位、运行方案变化调整过程,综述三峡水库运行调度关键技术研究进展和分析来水来沙变化情况。分别采用最可能洪水地区组成法和非一致性洪水频率分析两种途径,推求考虑上游水库群调蓄影响的三峡水库运行期设计洪水及特征水位。结果表明:近10年三峡入库泥沙量比初设成果减少了84.4%,宜昌站水文情势IHA-RVA综合指标为74%、发生了重度改变,三峡水库运行期1000年一遇7~15 d洪量减少了约81.5亿~142.8亿m^(3),初设确定汛限水位的主要制约因素(防洪、泥沙)发生了很大的变化。原单站设计洪水及确定的三峡水库175-155-145 m运行方案,已无法满足新时期水资源高效利用和生态环境保护的新需求。建议把三峡水库运行方案调整为175-160-155 m,主汛期水位在155~160 m区间动态控制运行,长江中下游梅雨结束后应考虑提前蓄水,8月底蓄至163 m左右,9月底蓄至165 m,10月底蓄满。该方案在保证大坝和下游防洪安全的前提下,汛期减少弃水并增加枯水期补水量,预计可增发10%左右的发电量;抬高运行水位也有利于库区航运和减少消落带;9月份尽量不蓄水或少蓄水,可减少蓄水期对下游河道及两湖生态环境的不利影响,具有巨大的经济、社会和生态环境等综合利用效益。当预测预报长江流域可能发生流域性大洪水时,尽快将库水位消落至汛限水位145 m,确保大坝和下游防洪安全。

基于电气自动化的灌溉水电双控系统设计

针对我国灌溉系统水资源利用率较低的问题,基于电气自动化对灌溉水电双控系统进行了设计。灌溉水电双控系统主要组成包括控制模块、信息采集模块、收费管理模块、执行模块和通信模块。为了实现节水灌溉,提升水利用率,在管理方面对控制系统软件进行设计,在技术方面对控制系统算法进行设计。为了验证灌溉系统的性能,对系统进行了数据计量准确性试验和节水灌溉运行试验。试验结果表明:系统可以准确地测量用电量和用水量,且可自动启动节水灌溉。

基于模型参考自适应的水肥一体化控制系统设计

针对水肥混合过程中水肥EC值精准控制的问题,设计一个基于模型参考自适应的水肥一体化决策和控制系统。建立母液动态调控模型,并通过该模型设计模型参考自适应控制器。仿真试验结果显示,模型参考自适应控制相较于模糊PID控制,在跟踪试验中超调量降低1.2%,调整时间减少12.6 s,阶跃试验中超调量降低14.4%,调整时间减少超过2 s,抗干扰能力优于模糊PID控制。通过3种方式进行田间试验,对比模糊PID控制和人工灌溉方式,采用模型参考自适应控制能够使番茄株高分别提高15.7%和35.6%,茎粗分别增长11.1%和18.6%,产量分别提升23.3%和48.1%,结果表明,模型参考自适应控制优于模糊PID控制和人工灌溉方式,从而验证模型参考自适应控制的有效性,为精准施肥灌溉提供技术支持。

黄河流域煤矿矿井水综合利用问题分析及管控建议

黄河流域煤炭资源丰富,但水资源匮乏,如何在确保生态环境安全的前提下,最大程度实现煤矿矿井水的综合利用,成为该地区迫切需要解决的热点问题.黄河流域煤矿矿井水的涌水量分布不均,呈南多北少的特征,且水质具有高矿化度、碱性或弱碱性以及高氟化物的特点.结合当前煤矿矿井水主要的综合利用途径,在总结国内外煤矿矿井水排放管控要求的基础上,识别当前制约我国煤矿矿井水综合利用的原因包括外排受较多制约,缺少供水需求,缺少对水质标准、技术规范和政策监管的改善,处理过程中缺乏技术规范化指导以及缺乏鼓励矿井水综合利用的措施等.针对以上问题,从实事求是地制订煤矿矿井水外排的管理要求、科学制订基于不同利用途径的煤矿矿井水综合利用水质标准、加强煤矿矿井水处理技术的推荐和引导以及建立多部门协作机制等方面,提出提高黄河流域煤矿矿井水综合利用率的建议,以期为合理利用水资源、确保生态环境安全、促进黄河流域高质量发展提供支撑.

水淹水窜油藏的数值模拟开发方案对比分析

随着开发的深入,大多数油田已经进入高含水阶段。以新疆某水淹水窜油藏为研究对象,该区水淹严重,开发效果差。针对上述问题,利用油藏数值模拟手段,对改善开发效果的4种技术方案进行研究。研究结果表明,深层调剖方案增产效果明显,可有效提高日产油量、降低含水率;浅层调剖方案作用范围、受效时间有限,措施效果较差;井网调整方案含水率明显下降,产油量上升,增油效果介于深层调剖与浅层调剖之间;周期注水增油效果最差,呈负增长趋势。经方案对比分析,建议对研究区水窜严重的井实施深层调剖。该研究为同类水淹水窜油藏改善开发效果提供了重要理论指导和借鉴。

三峡工程蓄水运用20年综合效益发挥与展望

三峡工程自2003年蓄水发电至今已运行20 a,初步设计主要功能全部实现,并适应运行条件变化和发展需求持续优化运行方式,防洪、发电、航运、水资源利用等综合效益全面发挥。截至2023年底,三峡工程累计拦洪运用66次,拦蓄洪水超2 088亿m^(3),确保了荆江河段防洪安全,极大减轻了长江中下游防洪压力;累计发出清洁电能超16 600亿kW·h,相当于节约标准煤5.1亿t,减少二氧化碳排放13.3亿t;极大改善了库区与长江中游航道条件,累计通过货运量超20亿t,有力促进了长江航运快速发展;枯水期累计向下游补水约3 400亿m^(3),有效保障了长江中下游供水安全;生态调度成效显著,四大家鱼资源量明显恢复。为了应对频发的极端水文事件带来的风险和挑战,确保三峡工程长期安全运行和持续发挥巨大综合效益,从推进气象水文预报技术研究与应用、三峡水库调度运行方案优化、创新成果转化运用、智慧化管理等方面提出了下一步工作展望。

金沙江下游-三峡梯级水库2023年联合调度实践

金沙江下游-三峡梯级水库是治理和保护长江的关键性工程。为了进一步提高梯级水库应对持续枯水的能力,保障水资源综合利用效益全面发挥,结合2023年长江上游水雨情特点,全面分析了梯级水库应对持续枯水所实施的联合补水、汛期水位动态控制、联合蓄水等优化调度措施,总结提炼了梯级水库联合调度的成效和经验。实践结果表明:枯水期梯级水库累计向下游补水约243亿m^(3),有效保障了长江中下游供水安全以及航运、生态等综合效益;通过汛期抬水位、蓄水期精细化预报调度,有效提升了水资源利用效率,保障了梯级水库实现蓄满目标。提出的调度措施和经验可为今后流域控制性水库群联合调度方式优化提供重要参考。

汽包水位自动控制应用研究

对于钢铁冶金行业,转炉汽化余热利用系统在提升炼钢过程中的能源效率及降低成本方面具有重要应用。文章聚焦于转炉汽包水位控制在汽化系统中的关键作用,深入探讨了传统单冲量与双冲量控制方式的特性与不足,同时进一步详细剖析了三冲量控制系统的架构、运作机理及其优越性。三冲量控制系统通过综合运用多种控制变量,实现了对汽包水位的高精度控制,进而保障了汽化系统的稳定运行。三冲量控制系统的应用,不仅显著提升了转炉汽化余热利用系统的效能,同时为企业节能降耗、成本优化提供了强有力的技术支持。

水电站经济运行指标实时数字化研究

在传统的水电优化调度工作中,因水电站特性和管理单位的不同,存在对电站的水电经济运行管理评价方法和标准不统一的情况。该文通过介绍水电站经济运行实时数字化研究,按水电优化调度提高发电效益的两种主要途径,分别建立数学计算模型,对单电厂、梯级多厂和电网整体综合的经济运行指标进行数字化处理,分别以小时、日、月、年为阶段自动计算,实时展示优化调度结果,为综合评价水电优化调度成果提供更科学、合理、客观的数据量化指标依据,指导电网和水电厂优化调度工作。

AICD控水技术在南海东部油田的应用及适应性评价

AICD具有防水、控水、控气、防砂、增油、多目标一次完成的技术特点,能够实现抑制高含水井段产出、增大低含水井段产出,实现自动调整水平井段的产液剖面,达到控水增油的目的。本文依托南海东部油田AICD整体实施情况,通过分析应用效果,对该技术适应性进行了系统评价,对后续同类型油藏现场应用具有重要的参考价值。

多调整因子模糊控制的地下水水位自动监测方法

为提升地下水水位自动监测效果,研究一种基于多调整因子模糊控制的地下水水位自动监测方法。利用改进蝙蝠算法优化多调整因子,利用优化的多调整因子,设计多调整因子模糊控制器;将采集的地下水压力信号误差作为控制器的输入,输出压力传感器控制量,用于控制压力传感器的采集过程;在长短期记忆神经网络内输入采集的压力信号,输出地下水水位自动监测结果。实验证明:该方法可有效完成地下水水位自动监测工作,且监测误差较小;在不同降雨量时,该方法也能够有效监测地下水水位。

某国际旅游度假区周边开发中基于落地性的城市河道断面优化调整

城市河道是保障城市安全和社会经济发展的重要支撑,在进行区域开发时可能会遇到拟建河道与周边其他工程有冲突的情况。以某国际旅游度假区北片区河道为例,对河道断面进行优化调整。结果表明:河道断面的优化调整既保证了河道防汛除涝安全和活水畅流效果,又保证了周边其他项目能够顺利推进。