Concentrating solar thermal desalination: Performance limitation analysis and possible pathways for improvement
Concentrating solar thermal desalination: Performance limitation analysis and possible pathways for improvement
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DOI：
10.1016/j.applthermaleng.2020.116292
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发表时间：
2020-11
影响因子：
6.4
通讯作者：
Yanjie Zheng;Rodrigo A. Caceres Gonzalez;M. Hatzell;K. Hatzell
中科院分区：
文献类型：
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作者：
Yanjie Zheng;Rodrigo A. Caceres Gonzalez;M. Hatzell;K. Hatzell
太阳能热海水淡化是可持续制水的一种可行方法。目前的热法海水淡化技术存在比能耗高、能量不匹配等问题。聚光式太阳能集热器以高温能量运行，海水淡化系统以低温能量运行，导致大量的(火用)破坏。在此，建立了一个理想聚光太阳能蒸馏过程的热力学模型，以评估系统集成和性能限制(比产水量)。研究了三种不同的加热结构，以了解太阳能集热器的温度、集中度和回收率对系统性能的影响。在最佳吸收塔温度为507K、浓度比为10的可逆太阳能蒸馏系统中，当回收率(Rr)接近于零时，最大比产水量可达~166.3 GS−1 m−2。建立了考虑系统不可逆性的内可逆热机模型。不可逆性(R=0.001 K/kW或0.005 K/kW)系统的产水率下降到8.8GS−1m−2(rr=51.4%)和1.9gS−1m−2(rr=65.2%)。为了有效地将太阳能集热器与热海水淡化系统集成在一起，采用适当的加热配置并控制吸收器温度、系统回收率和系统不可逆性至关重要。
Solar thermal desalination is a viable approach for sustainable water production. Current thermal desalination technologies suffer from high specific energy consumption and energy mismatch. Concentrating solar collectors operate with high temperature energy and desalination systems operate with low temperature energy which leads to large exergy destruction. Herein, a thermodynamic model of an ideal concentrating solar-distillation process is developed to evaluate system integration and performance limitations (specific water production). Three different heating architectures are examined to understand how solar collector absorber temperature, concentration ratio, and recovery ratio impact system performance. A reversible solar distillation system operating with a concentration ratio of 10 at the optimal absorber temperature of 507 K can achieve a maximum specific water production of~ 166.3 gs− 1 m− 2 as the recovery ratio (rr) approaches zero. An endo-reversible heat engine model was formulated to consider system irreversibilities. Systems with irreversibilities (R= 0.001 K/kW or 0.005 K/kW) experience a decrease in the water production rate to 8.8 gs− 1 m− 2 (rr= 51.4%) and 1.9 gs− 1 m− 2 (rr= 65.2%). For efficient integration of solar collectors with thermal desalination systems, it is critical to adopt appropriate heating configurations and control absorber temperatures, system recovery ratio, and system irreversibilities.