平板太阳能集热器为人们的日常生活提供热水, 微量的重金属元素和杂质会随着热水从集热器内部流出, 对环境产生潜在影响, 同时也威胁人们的身体健康。 因此, 有必要对平板太阳能集热器闷晒的水质样品进行检测分析。 为了提高集热器水质样品检测结果的可信度, 集热器在闷晒时所使用的水均为超纯水, 且在闷晒前利用超纯水对集热器进行冲洗, 以降低管道内的杂质对结果的影响。 所测试的平板太阳能集热器的管道材料均为TP₂磷脱氧铜。 检测的标准溶液包含As, Ca, Cu, Mg, Ni和Zn等21种重金属元素, 浓度梯度分别为0.2, 0.4, 0.8和1.6 mg·L^-1。 以铝基底蓝膜、 黑铬和阳极氧化三种涂层的平板太阳能集热器闷晒后的水质样品为研究对象, 采用ICP-OES(inductively coupled plasma optical emission spectrometry)法定量分析水质样品中重金属元素的含量, 并通过信噪比确定了各重金属元素的最佳分析谱线。 标准溶液中部分重金属元素的最佳分析谱线分别为(nm): As(188.979), Ca(317.933), Zn(206.200), V(290.880), Cu(327.393), Ni(231.604), Sb(206.836), Pb(220.353)。 结果表明, ICP-OES可以同时准确分析多种重金属元素的含量, 水质样品中重金属元素的含量越高, 则元素谱线的振幅越大。 平板太阳能集热器闷晒的水质样品中不含有Be, Co, Cd, Cr, Fe, Li, Mn, Mo, Se, Sr, Tl和Ti等12种重金属元素, 但含有As, Ni, Cu, Ca, Mg, V, Pb, Zn和Sb等9种重金属元素。 水质样品中重金属元素含量的变化规律是随着平板太阳能集热器闷晒时间的增加而增大, 增大至峰值后又随着集热器闷晒时间的增加而减小, 且逐渐减小至较低含量。 得出了重金属元素随闷晒时间的变化规律, 给出了不同种类重金属元素的超标量和超标的闷晒时间。 以城市供水水质标准(CJ/T 206—2005)对相关重金属元素的限值作为参考, 水质样品中Cu, Ni, Zn元素的含量均未超过该标准中的限值。 但是, 平板太阳能集热器水质样品中As, Pb和Sb重金属元素的含量在闷晒了8 d后均出现了不同程度的超标, As, Pb和Sb的最大超标量分别为0.007, 0.006和0.004 mg·L^-1。 其中, 蓝膜集热器水质样品中As元素的超标量最高, 黑铬集热器水质样品中Pb的超标量最高, 阳极氧化集热器水质样品中As的超标量最高。 检测结果对厂家和用户都具有一定的参考意义, 说明了集热器管道材料的制备工艺有待进一步提高, 以减少重金属元素的析出量。 也为后续对平板太阳能集热器的研究和国家标准的制定提供一定的参考。

The flat-plate solar collectors (FPSCs) provide hot water for people’s daily life, and the minute heavy metals and impurities come out from inside collectors with hot water. Heavy metals have a potential impact on the environment, meanwhile, it also threatens people’s health. So it is necessary to detect the stagnant water samples of FPSCs. To improve the reliability of the test results of FPSC water samples, the ultra pure water was used for the stagnation of the FPSC. The ultra pure water was used to wash the FPSCs before stagnation to reduce the effect of pipe impurities on the results. The pipes materials of FPSC were made of TP₂ phosphorous deoxy copper. The standard solution contains 21 kinds of heavy metal elements, such as As, Ca, Cu, Mg, Ni, Zn and so on. The concentration gradients of the standard solution were 0.2, 0.4, 0.8 and 1.6 mg·L^-1, respectively. The blank sample and standard solution should be analyzed before testing the water sample. The water samples of different aluminum substrate FPSC (the blue-film coating, the black chromium coating and the anode oxidizing coating) were analyzed, and the content of heavy metal elements in water samples were also detected by ICP-OES method. Moreover, the best analytical spectrum of the 21 heavy metal elements were ensured by relevant parameters. The best analytical spectrum of partial heavy metal elements of the standardsolution were respectively (nm): As(188.979), Ca(317.933), Zn(206.200), V(290.880), Cu(327.393), Ni(231.604), Sb(206.836), Pb(220.353). It was shown that ICP-OES can simultaneously detect the content of various heavy metal elements in water samples accurately. The higher content of heavy metal elements in water samples, the greater the amplitude of the spectrum. There were not 12 heavy metal elements (Be, Co, Cd, Cr, Fe, Li, Mn, Mo, Se, Sr, Tl, Ti) in the water samples of three kinds of FPSCs, but 9 heavy metal elements (As, Ni, Cu, Ca, Mg, V, Pb, Zn, Sb) were detected in the same experiments. The changeable rule of heavy metal content in water samples showed that the heavy metal content increases with the FPSCs stagnation time, the heavy metal content increases to the peak value and then decreases with the FPSCs stagnation time, and then it decreases to the lower content gradually. The changeable rule of heavy metal content with the stagnation time was obtained with the analysis of the stagnant water samples of the FPSCs, and the superscalar and the excessive stagnation time of different heavy metal elements were also given too. The limit value of water quality standards for urban water supply (CJ/T 206—2005) for heavy metal elements was taken as reference, so these heavy metals elements (Cu, Ni, Zn) of water samples of three kinds of FPSCs were not more than that of the limit of the national standard. However, the contents of As, Pb and Sb in water samples of three kinds of FPSCs exceeded the limit of the standard after 8 days stagnation. The maximum superscalar of As, Pb and Sb elements were 0.007, 0.006 and 0.004 mg·L^-1, respectively. And the superscalar of the As elements was the highest in the water samples of the blue-film coating collector and the anode oxidizing coating collector, and the superscalar of the Pb elements was the highest in the water samples of the black chromium coating collector. The detection results had certain reference significance to the manufacturers and the customers, and the technology of FPSC’s pipes should be further improved to reduce the precipitation of heavy metals. The research results can also provide some references for the research of the FPSC and the establishment of national standards.