水泥內(nèi)襯和水泥修復(fù)對(duì)水質(zhì)的影響
The influence of prefabricated pipe cement coatings and those made during pipe renovation on drinking water quality
（水泥內(nèi)襯和水泥修復(fù)對(duì)水質(zhì)的影響）
Anna M?yńska and Micha? Zielina
Cracow University of Technology, Faculty of Environmental Engineering, Institute of Water Supply and Environmental Protection, ul. Warszawska 24, 31-155 Cracow, Poland
1.2 The risk of water contamination resulting from contact with the cement mortar coating
The risk of the leaching chemical elements from the cement coatings into the water is determined by the type of cement used. For example, the greatest amount of aluminium is leached from a high-alumina cement coating. In turn, the greatest amount of calcium is leached from a Portland cement coating [9, 10]. In the case of using blast furnace slag cement for coating, the risk of leaching a greater amount of aluminium and calcium is rather small. Many experiments proved that the greatest impact of cement coating on water quality initially is mainly related to the significant growth of pH [4, 10, 12–15] and aluminium concentration [4, 10, 13–15]. It is also probable that some heavy metals will be leached from the cement coating into the water. Numerous investigations on leaching trace elements from cements into the water were conducted and described in the literature [4, 13–17].
Even a small amount of heavy metal in the human body can contribute to many different health problems. In the Netherlands, in 1996, a great amount of aluminium leaching from a new cement coating was noticed. This leached aluminium contributed to the death of some patients in a haemodialysis centre as a consequence of aluminium poisoning. Aluminium was leached to the water from a newly-installed water system covered inside by a protective cement coating. The concentration of aluminium was forty times higher than the specified limit [18]. Thus, the concentration of aluminium in water making contact with a cement coating in the initial period of time should be controlled.
Since both pipe cementing techniques and type of used cements significantly influence the dissolution and leaching of chemical components from the cement coating, a comparison of cement coatings manufactured in factories and prepared on a building site during renovation on water quality was performed in this study. The paper presents the change of chemical elements such as aluminium, chromium, lead and cadmium in water samples coming into contact with two different cement coatings - manufactured in a factory and prepared in a laboratory.
1.2 與水泥砂漿涂層接觸導(dǎo)致水污染的風(fēng)險(xiǎn)
從水泥涂料中浸出化學(xué)元素到水中的風(fēng)險(xiǎn)取決于所用水泥的類型。 例如，最大量的鋁從高鋁水泥涂層中浸出。 反過(guò)來(lái)，最大量的鈣從波特蘭水泥涂層中浸出[9,10]。 在使用高爐礦渣水泥進(jìn)行涂覆的情況下，浸出更多鋁和鈣的風(fēng)險(xiǎn)相對(duì)小一些。 許多實(shí)驗(yàn)證明，水泥涂層對(duì)水質(zhì)的影響最初主要與pH [4,10,12-15]和鋁濃度[4,10,13-15]的顯著增長(zhǎng)有關(guān)。 一些重金屬也可能從水泥涂層中浸出到水中。 從水泥中浸出微量元素到水中的大量研究進(jìn)行了描述，并在文獻(xiàn)[4,13-17]中進(jìn)行了描述。
即使是人體中的少量重金屬也會(huì)導(dǎo)致許多不同的健康問(wèn)題。 在荷蘭，1996年，人們注意到從水泥涂層中浸出了大量的鋁。 由于鋁中毒，這種浸出的鋁導(dǎo)致血液透析中心的一些患者死亡。 鋁從新安裝水泥內(nèi)襯中浸入水中。 鋁的濃度比規(guī)定的極限高40倍[18]。 因此，應(yīng)控制在初始時(shí)間內(nèi)與水泥涂層接觸的水中鋁的濃度。
由于管道水泥內(nèi)襯技術(shù)和使用過(guò)的水泥的類型都會(huì)顯著影響水泥涂層中化學(xué)成分的溶解和浸出，因此本研究對(duì)工廠生產(chǎn)的水泥涂料和在水質(zhì)改造期間在施工工地上水泥涂料修復(fù)進(jìn)行了比較。 本文介紹了水樣中鋁，鉻，鉛和鎘等化學(xué)元素與兩種不同水泥涂料接觸的變化 - 在工廠生產(chǎn)并在實(shí)驗(yàn)室制備。
