栲胶法脱硫中脱硫塔堵塞原因分析及预防措施探讨

介绍了煤气脱硫的多种方法及栲胶法脱硫的优点,阐述了栲胶法脱硫的原理。通过分析栲胶法脱硫中脱硫塔堵塞的原因,提出了栲胶法脱硫中预防脱硫塔堵塞的各种措施:在硫容为0mg/L￣200mg/L时,控制栲胶质量浓度为3g/L￣5g/L,钒酸盐质量浓度为2g/L￣3g/L,pH≤9,喷淋密度≥20m3/(m2.h)等。     

冰浆生成器中抑制冰粘附的研究

冰浆中含有大量微小冰晶粒子,因此表现出有极好的流动、传热和储能特性。冰浆生成过程中,冰晶微粒易粘附在换热壁面,降低传热效率,增加流动阻力,甚至引起冰堵,影响冰浆的持续生成。分析了冰粘附特性,综述冰浆技术中冰移除技术的研究进展,建立冰浆生成实验台,采用综合控制制冰溶液和载冷剂流速的方法抑制冰堵的发生。     

金沙江白格滑坡残留体失稳堵江风险分析

2018年10月10日和11月3日,金沙江上游白格滑坡两次滑动形成堰塞湖,对下游造成了巨大破坏。目前其滑源区边界外仍存在K1、K2和K3等3处规模较大的残留体,有再次失稳堵江的可能性,对下游4座在建水电站构成威胁。受滑坡区自然地理地质条件制约,对白格滑坡残留体的规模、可能的失稳模式、一次失稳体积等方面的研究工作较少,不能为金沙江上游相关建设风险管理提供支撑。针对上述问题,2019年对滑坡残留体开展了精细地形测量、变形现象详细调查、深部结构探测等工作,系统分析了三处残留体的体积、失稳方式、可能的失稳组合;在考虑失稳体的铲刮效应、运动轨迹、松方系数等基础上对残留体入江规模进行了分析;根据河谷地形数据,基于PFC3D软件模拟和“10·10”、“11·3”两次白格堰塞体的形态特征,对不同失稳规模进行了堰塞体堆积形态预测。结果表明,三处残留变形体体积分别为159.3×104m3、460×104m3、142×104m3;滑坡残留体存在小规模坍塌、大范围卸荷变形、一定规模岩土滑移失稳三种变形破坏形式;最危险失稳工况以1-4、2-1、3-1、3-2四个亚区同时失稳可能性最大,失稳总体积达271×104m3;白格滑坡残留体不同失稳工况下,沿主滑槽入江堆积最大堆积高度47.5m,堆积高程2937.5m。沿白格滑坡凹槽上游斜坡入江堆积最大堆积高度28.7m,堆积高程2923.7m。     

某高矿化度砂岩型铀矿地浸开采堵塞机理的研究

新疆某高矿化度地下水分布区砂岩型铀矿采用酸法和碱法地浸时易出现堵塞,采用地球化学模式PHREEQCI模拟和实验研究的方法对堵塞进行了探讨。结果表明,堵塞主要是因为地下水的矿化度(TDS)、Ca2+、Mg2+、SO42-、HCO3-浓度过高,分别为8～12g/L、386.17～775.95 mg/L、250.83～377.21mg/L、2 036.47～2 436.08mg/L、108.66～527.55mg/L,方解石和石膏临近饱和状态;采用酸法和碱法地浸工艺分别会产生石膏和方解石沉淀而引起化学堵塞。该砂岩型铀矿适合采用稀释或水处理—弱碱性地浸工艺。     

气膜孔堵塞对叶片吸力面换热性能影响

为研究热障涂层喷涂过程造成的气膜孔堵塞对叶片吸力面换热特性的影响,利用数值模拟方法分析了叶片吸力面气膜孔堵塞比为0.2~0.8时传热系数的变化规律。将吹风比作为控制冷热流体流量比例的气动参数,在其变化范围为0.5~2.0情况下,详细分析了气膜孔堵塞对孔下游肾形涡、叶片壁面传热系数二维分布和展向平均传热系数的影响。结果表明：在吹风比相同的情况下,堵塞比越大,传热系数增幅越大;堵塞使肾形涡尺度和强度显著增大,导致壁面传热系数增大,吹风比越大,这种效应越明显;相比于无堵塞情况,堵塞比为0.2时传热系数基本不变,堵塞比为0.5时传热系数增大5%~7.2%,堵塞比为0.8时传热系数增大9%~12%。     

有机氟硼酸在王家岗敏感性地层的应用

根据3口井岩心矿物组成及碳酸盐含量数据,认为王家岗沙四段砂岩储层土酸和低伤害酸酸化效果差的原因,是储层碳酸盐、泥质含量高,酸岩反应速度快,反应产物产生一次及二次沉淀,乏酸液反排困难,在这类地层可采用有机氟硼酸体系。根据3口井储层岩心溶蚀率及酸化淤渣率数据,得到了各适用于某一口井的3个混合酸:4%/4%、6%/4%、4%/12%的醋酸/氟硼酸。筛选了酸液缓蚀剂KX1 7,N80钢片在加入1%KX1 7和5%NH4Cl的醋酸/氟硼酸液中80℃腐蚀速率为0.45～2.5g/m2·h。注入由3个混合酸配成的酸液使对应岩心的渗透率分别增大25%、76%、52%。在3口油井用该有机氟硼酸液酸化解堵,均获得了成功。较详细地介绍了在一口新投产不出油的井用醋酸/氟硼酸酸化液酸化,用液态CO2助排的施工情况和施工后产油情况。图3表5参3。     

降低海绵钛生产过程蒸馏通道堵塞率研究

以实际生产情况为依据,对蒸馏通道堵塞的影响因素进行了系统分析,并提出了具体改进措施。结果表明,蒸馏通道堵塞的主要原因有真空系统能力不足、喷淋水温度控制不合理、系统气密性差、设备故障和蒸馏负荷大。控制真空蒸馏过程真空度小于4Pa、蒸馏阶段喷淋水温度控制在合理范围可有效降低蒸馏通道堵塞率。     

Data-driven modelling of turbine wake interactions and flow resistance in large wind farms

Turbine wake and local blockage effects are known to alter wind farm power production in two different ways: (1) by changing the wind speed locally in front of each turbine and (2) by changing the overall flow resistance in the farm and thus the so-called farm blockage effect. To better predict these effects with low computational costs, we develop data-driven emulators of the ‘local’ or ‘internal’ turbine thrust coefficient $C_T^{\ast }$ as a function of turbine layout. We train the model using a multi-fidelity Gaussian process (GP) regression with a combination of low (engineering wake model) and high-fidelity (large eddy simulations) simulations of farms with different layouts and wind directions. A large set of low-fidelity data speeds up the learning process and the high-fidelity data ensures a high accuracy. The trained multi-fidelity GP model is shown to give more accurate predictions of $C_T^{\ast }$ compared to a standard (single-fidelity) GP regression applied only to a limited set of high-fidelity data. We also use the multi-fidelity GP model of $C_T^{\ast }$ with the two-scale momentum theory (Nishino & Dunstan 2020, J. Fluid Mech. 894, A2) to demonstrate that the model can be used to give fast and accurate predictions of large wind farm performance under various mesoscale atmospheric conditions. This new approach could be beneficial for improving annual energy production (AEP) calculations and farm optimization in the future.     

The flow in the induction and entrance regions of lab-scale wind farms

With the increasing demand for wind energy, it is important to be able to understand and predict the available wind resources. To that end, the present wind tunnel study addresses the flow in the induction and entrance region of wind farms through particle image velocimetry, with focus on differences between actuator disks and two-bladed rotating wind turbine models. Both staggered and aligned farm layouts are examined for three different incoming wind directions. For each layout, 69 disks or turbines are used, and the field of view ranges from 12 rotor diameters upstream of the farms to 8 diameters downstream of the first row. The results show that the induction, or blockage effect, is higher for the disks, even though the thrust (or drag) coefficient is the same. In contrast, the wake is stronger downstream of the turbines. The orientation and layout of the farm do not have a major impact on the results. Modal decomposition of the flow shows that the flow structure similarity between the disk and turbines improves downstream of the second row of wake generating objects, indicating that the substitution of wind turbines by actuator disks is more appropriate for wind farms than for the investigation of single wakes.