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從水管藍顆粒看官僚文化

從水管藍顆粒看官僚文化
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近日,紅磡邨二期,啟晴邨和牛頭角下邨等多條租住屋邨在水管翻新工程後發現的顆粒引起居民不安。在議員介入後,發展局、水務署及房屋署等表示,該等藍色顆粒為銅鹽(鹼式碳酸銅)無毒。其出現是由於工人在使用過量焊接劑,殘餘的酸性容易在管內壁長出銅鹽,而該焊接劑屬水融,只要工程後沖洗足夠(新接喉管的20倍水量),便無事。

銅鹽

該等該等藍色顆粒由兩種鹼式碳酸銅組成,但非無害。它被「化學品全球調和制度」(GHS)定為有害,服後有害,容器標籤為「警告」;美國國家職業安全衛生研究所(NIOSH)的容忍程度為TWA 1 mg/m3。它雖然不在水溶,但在胃酸中可溶解(註1)。

講D唔講D

官員被議員質詢已有一定范式。他們基本上不講大話,但也不講真話,或事實及事實的全部。很多時,題目屬於相當專業或技術或政策的東西,他們便裝傻扮懵。就算被問錯了也不會指出其非,以免開罪對方。曾有一位政府的首席工程師在立法會的小組委員會內直斥對方其非,結果被議員團剿。此事流傳成為政府內高層技術人員的教訓。

問題所在

銅鹽可在氯化物的環境下加速生長(註2),而屋署工程所用的焊接劑有氯化物。雖則,該英國產品在多年前被水務署核准和得到英國水務中心的飲用水安全方面的認證(WRAS),肇事的『中國建築』是否用了大陸貨不得而知。

令人廢解的是,銅鹽是一種結晶。任何結晶都需要一段較長的時間生長。就算裝配工人在工程後(從水錶到室內的銅喉)沒有沖水,該住戶在晚間用水一定超過這段銅喉體積的20倍水量,不可能養出銅鹽結晶。為此,筆者了解過,三個被抽樣用戶並非獨居長者。

實驗室資料,種一顆千分之5毫米的銅鹽結晶需6小時,以此論之,這批顆粒至少在水管內長了一個月(註6)。

These green basic copper carbonate crystal particles are formed with a diameter of 5.0~6.5 μm, when the temperature keeps about 50 ºC , pH is about 7.0~7.5, and to react for 6h.

原來,在铅水事件後,政府為一此舊公屋換銅喉。但整棟樓的換喉不可能在數周內完成,用戶不可能被截水數周。因此,新工程分為兩段,第一段為總水錶到各戶門前,第二段為各戶水錶到其水喉頭。用戶發現的銅鹽是在第一階段生長的,但他們在新裝到戶銅管時發現,自然地以為是入戶水管工程所致,並向議員投訴。香港的水管專家為持牌水喉匠(註三)──「以建造、安裝、保養、更改、修理或移動消防供水系統或內部供水系統的人」。

調查食水含鉛量超標專責小組報告

食水含鉛超標調查委員會在2016年報告已關注到水管內滯留食水的影響(註四),報告發現,静水在48小時後,金屬開始飽和。

2 For the stagnation test, it was conducted by first thoroughly flushing the water supply chain for 15 hours. Water then remained stagnant in the water supply chain and water samples were taken at 0 hour, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 24 hours and 48 hours for determining the lead contents

2011年世衛標準

香港的食水安全參考世衛標準,世衛特別關注銅水喉的安裝,並指出,新裝水管必需全面沖洗、消毒及在用戶端取樣進行微生物測試。

If a temporary water supply is used recurrently, it is essential to fully flush the entire system with water containing a higher than normal disinfectant residual before restarting. When In addition, the system should be disinfected and flushed after maintenance or repairs, and the microbiological quality of the water should be checked, preferably before the system is returned to service.

水務署

水務署或其上級發展只在新建築物中的新裝供水系統有一套安全指引。它可能沒有考慮過鉛水事件所導致的大模範安裝、更改的指引。

因此,第一段工程的室外大喉安裝完成後,它可能被裝水,進行滲漏測試。承建商當然不會主動清水,風乾和消毒(世衛建議)。這樣,大量銅鹽便出現了。

官員處理

政府的食水專家應該看到問題,但他們在被傳媒和議員追殺的時間,截了一段沒相關的室內銅管點檔,然後與議員大談,沖水,焊接劑特性,洗沙隔,食咗無事等等。

這不無道理,因為,找出真相要鋸大喉,截全層食水,倒自已米。唔通全棟再重一次嗎?而且,於事無補,小市民食幾點銅鹽是無事的,可能比他們到茶餐廳吃所吸收的有害化學品為少。

備註

註一
Basic copper carbonate is a chemical compound, more properly called copper(II) carbonate hydroxide. It is an ionic compound (a salt) consisting of the ions copper(II) Cu2+ , carbonate CO2− 3, and hydroxide HO− . Sometimes the name is used for Cu 3(CO 3)2(OH)2, a blue crystalline solid also known as the mineral azurite. It too has been used as pigment, sometimes under the name mountain blue or blue verditer. https://en.wikipedia.org/wiki/Basic_copper_carbonate

Other names copper carbonate hydroxide, cupric carbonate, copper carbonate Both malachite and azurite can be found in the verdigris patina that is found on weathered brass, bronze, and coppe Both malachite and azurite basic copper carbonates have been used as pigments It has also been used in some types of make-up, like lipstick, although it can also be toxic to humans

Basic copper carbonate is decomposed by acids, such as solutions of hydrochloric acid HCl, into the copper(II) salt and carbon dioxide.

Hazard statements form part of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS). They are intended to form a set of standardized phrases about the hazards of chemical substances and mixtures that can be translated into different languages.[1][2] As such, they serve the same purpose as the well-known R-phrases, which they are intended to replace.

H302: Harmful if swallowed

H315: Causes skin irritation

H319: Causes serious eye irritation

H335: May cause respiratory irritation

GHS07: Harmful

Acute toxicity (oral, dermal, inhalation), category 4

Skin irritation, categories 2, 3

Eye irritation, category 2A

Skin sensitization, category 1

Specific target organ toxicity following single exposure, category 3

Respiratory tract irritation

Narcotic effects

Not used[3]

with the "skull and crossbones" pictogram

for skin or eye irritation if:

the "corrosion" pictogram also appears

the "health hazard" pictogram is used to indicate respiratory sensitization

P261: Avoid breathing dust/fumes/gas/mist/vapours/spray. [As modified by IV ATP]

P305+351+338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do – continue rinsing.

For chemicals, the chemical regulation is usually expressed in parts per million (ppm), or sometimes in milligrams per cubic meter (mg/m3). Units of measure for physical agents such as noise are specific to the agent.

TWA 1 mg/m3 (as Cu)

註二
The composition of the patina can vary, in a maritime environment depending on the environment a basic chloride may be present, in an urban environment basic sulfates may be present.[3]

註三
食水含鉛超標調查委員會

《2017年水務設施(修訂)條例草案》委員會

首次會議

日 期:2017年5月19日(星期五)

時 間:上午10時45分

地 點:立法會綜合大樓會議室2

因應食水含鉛超標調查委員會於二零一六年五月公布的建議,水務署正諮詢食水安全國際專家小組的意見,以便就食水水質標準、抽樣規程、經優化的水質監測計劃和水安全計劃等事宜擬訂整全計劃,保障食水的安全和質素。

綱領(2)

二零一七至一八年度的撥款較二零一六至一七年度的修訂預算增加1,330萬元(5.2%),主要由於為推行食水含鉛超標調查委員會提出的建議而開設7個職位、進行保障食水水質顧問研究和購買濾水化學品,令所需撥款增加。部分增加的開支,因購置化驗所設備需求減少而得以抵銷。

刪除原文

新修訂

條: 14 消防供水系統及內部供水系統的建造等

“對消防供水系統及內部供水系統的建造等的限制”。

(1) 除第(2)款另有規定外,任何人除非獲得水務監督書面許可,否則不得建造、安裝、更改或移動消防供水系統或內部供水系統。

“(1) 除第(2) 款另有規定外,除非水務監督已對消防供水系統或內部供水系統的建造、安裝、更改或拆除,給予書面許可,否則任何人不得進行該項建造、安裝、更改或拆除。

(1A) 任何人違反第(1) 款,即屬犯罪。

(2) 如水務監督認為消防供水系統或內部供水系統的更改性質輕微,則可免除第(1)款取得許可的規定。

(2A) 上述書面許可,可由水務監督主動給予,亦可由水務監督應持牌水喉匠的申請而給予。

(3) 消防供水系統或內部供水系統的建造或安裝須按訂明的方式進行,而該消防供水系統或內部供水系統的喉管及裝置的性質、大小及品質須與所訂明者相同。

(4) 任何人違反第(1)或(3)款的規定,即屬犯罪。

“(4) 如就消防供水系統( 或其任何部分) 或內部供水系統( 或其任何部分) 的建造或安裝而言,第(3) 款遭違反,每名下述人士均屬犯罪——

(a) 如該項建造或安裝,是在某人的指示及督導下進行的——該人;

(b) 進行該項建造或安裝的人( 不論該人是否在另一人的指示及督導下,進行該項建造或安裝);

(c) 如根據第(2A) 款對該項建造或安裝給予的書面許可,是應某持牌水喉匠的申請而給予的,而該水喉匠並非(a) 或(b) 段所述的人——該水喉匠。

(5) 被控犯第(4) 款所訂罪行的人,如證明以下事項,即為免責辯護——

(a) 如屬第(4)(a) 或(c) 款所述的人——該人已採取所有合理步驟,確保進行該項建造或安裝不會違反第(3) 款;或

(b) 如屬第(4)(b) 款所述的人——

(6) 凡第(4)(a) 款所述的人,沒有按合理頻密程度( 在顧及第(7) 款所列事宜屬合理者) 作出視察,以確保有關的建造或安裝(有關工程),是遵照本條例進行的,則在不局限第(5)(a) 款的原則下,該人不得視為已採取所有合理步驟。

(7) 有關事宜是——

(a) 有關工程的性質;

(b) 有關工程涉及的風險;及

(c) 進行有關工程的人的知識及經驗。”。

15.由持牌水喉匠進行的建造等“誰可進行指明水管工程

(1)除第(2)款另有規定外,任何人不得建造、安裝、保養、更改、修理或移動任何消防供水系統或內部供水系統,但持牌水喉匠或水務監督授權的公職人員,則屬例外。“(1) 除第 (2) 款另有規定外,並非指定人士的人,不得進行指明水管工程。”。

(2)水務監督認為是性質輕微的消防供水系統或內部供水系統的更改或修理工作, “可由並非指定人士的人進行。”或水龍頭的更換墊圈工作,可由不屬持牌水喉匠的人或不屬水務監督授權的公職人員的人進行。

(3)除第(2)款另有規定外,任何人 ——

(a)違反第(1)款的規定;或

(b)僱用或容許不屬持牌水喉匠的人或不屬水務監督授權的公職人員的人建造、安裝、保養、更改、修理或移動消防供水系統或內部供水系統,即屬犯罪。

“(3) 任何人違反第 (1) 款,即屬犯罪。

(4) 任何人僱用或准許並非指定人士的人,進行指明水管工程,即屬犯罪。

(5) 被控犯第 (4) 款所訂罪行的人 (被告人 ),如證明以下事項,即為免責辯護——

(a) 被告人相信,進行有關指明水管工程的人是指定人士;及

(b) 被告人相信該情況,屬合理之舉。

(6) 在本條中——

指定人士 (designated person) 指——

(a) 持牌水喉匠;

(b) 註冊水喉技工;

(c) 註冊水喉技工 ( 臨時 );

(d) 在持牌水喉匠或註冊水喉技工的指示及督導下進行指明水管工程的人;或

(e) 水務監督授權的公職人員。”。

“15A. 進入非住用處所及提問等的權力

(1) 獲授權人員可於任何合理時間——

(a) 進入任何非住用處所,以確定是否有人正在或曾經在違反第 15 條的情況下,於該處所進行指明水管工程;或

(b) 進入任何其他非住用處所,以行使 (a) 段賦予的權力。

(2) 獲授權人員根據第 (1)(a) 款進入任何處所後,可行使任何或所有以下權力——

(a) 對該處所及該處所的消防供水系統或內部供水系統,拍攝照片;

(b) 要求於該處所發現的人,回答關於以下事宜的問題——

(i) 該人是否正於或曾經於該處所,進行指明水管工程;及

(ii) 該人是否持牌水喉匠、註冊水喉技工或註冊水喉技工 ( 臨時 ) (合資格人士 );

(c) 如於該處所發現的人,表示自己是合資格人士——

(i) 要求該人出示證明文件,以支持該表述;或

(ii) 如該人不能即時出示該證明文件——要求該人在該人員規定的合理限期內,在該人員規定的地點,出示該證明文件;

(d) 如於該處所發現的人,表示自己並非合資格人士——

(i) 要求該人回答關於以下事宜的問題:該人是否正於或曾經於該處所,在持牌水喉匠或註冊水喉技工的指示及督導下,進行指明水管工程;及

(ii) 如該人對該問題的答案為 “是” ——要求該人將給予指示及督導的人的姓名及聯絡方法,提供予該人員;

(e) 該人員如合理地懷疑,有人正於或曾經於該處所違反第 15 條——要求於該處所發現的人,向該人員提供任何符合以下描述的資料——

(i) 該人員合理地相信,該資料攸關確定是否有人正在或曾經違反第 15 條;及

(ii) 該人員合理地相信,該人知悉該資料;

(f) 該人員如合理地懷疑,於該處所發現的人,正在或曾經違反第 15 條,則在將可能構成有關涉嫌違例事項的作為或不作為告知該人後——

(i) 於一段合理時間內,將該人扣留於該處所內,以就該涉嫌違例事項,作進一步查訊;及

(ii) 要求該人向該人員提供該人的姓名、地址、電話號碼、身分證明,以及該人員合理地需要的其他個人詳情。

(3) 任何人不遵從根據第 (2) 款提出的要求,即屬犯罪。

(4) 任何人作出任何在要項上屬虛假或具誤導性的陳述,或提供任何在要項上屬虛假或具誤導性的資料,以充作遵從根據第 (2) 款提出的要求,即屬犯罪。

(5) 被控犯第 (3) 款所訂罪行的人,如證明在有關指控罪行發生時,該人對不遵從有關要求一事,有合理辯解,即為免責辯護。

(6) 被控犯第 (4) 款所訂罪行的人,如證明在有關指控罪行發生時,該人不知道、無理由懷疑、且即使已作出合理努力亦不能確定,有關的陳述或資料在要項上屬虛假或具誤導性,即為免責辯護。

(7) 本條賦予的權力,是增補而非減損第 12 條賦予的權力。

(8) 在本條中——

安老院 (home for elderly persons) 指《安 老 院 條 例》( 第459 章 ) 第 2 條界定的安老院;

非住用處所 (non-domestic premises) 指並非作供人居住之用的處所 ( 而作供人居住之用的處所,包括作以下用途的處所:酒店、旅館、附服務設施寓所、集體寢室、安老院、殘疾人士院舍、幼兒中心、托兒所,或相類的處所 );

殘疾人士院舍 (home for persons with disabilities) 指《殘疾人士院舍條例》( 第 613 章 ) 第 2 條界定的殘疾人士院舍;獲授權人員 (authorized officer) 指水務監督或水務監督以書面授權的公職人員。”。

條例草案第 3 及 12 條建議修訂第 102 章第 2 條,以及在第 102 章加入新訂附表,以訂明註冊水喉技工及註冊水喉技工(臨時)指根據《建造業工人註冊條例》(第 583 章) 註冊為下述技工的人:屬新訂附表所指明 工種分項 的相關註冊 熟練技工、註冊半熟練技工、註冊熟練技工(臨時)或註冊半熟練技工(臨時 )。 根 據 擬 在 第 102 章加入的新訂第 38A 條 , 發展局局長("局長")將獲賦權,藉於憲報刊登的公告,修訂該新訂附表。該公告為附屬法例,可由立法會根據《釋義及通則條例》(第 1 章)第 34 條作出修訂。

附表

[ 第 2 及 38A 條 ]

註冊水喉技工及註冊水喉技工 ( 臨時 )

第 1 部

註冊水喉技工

1. 就建造、安裝、保養、更改、修理或拆除消防供水系統而言,或就安裝水錶而言,根據《建造業工人註冊條例》( 第 583 章 ) 註冊為下述技工的人——

(a) 屬水喉工工種分項的註冊熟練技工;

(b) 屬地渠及喉管工 ( 全科 ) 工種分項的註冊熟練技工;

(c) 屬消防設備技工 ( 全科 ) 工種分項的註冊熟練技工;

(d) 屬消防機械裝配工工種分項的註冊熟練技工;

(e) 屬水喉工工種分項的註冊半熟練技工;或

(f) 屬消防機械裝配工工種分項的註冊半熟練技工。

2. 就建造、安裝、保養、更改、修理或拆除內部供水系統而言,根據《建造業工人註冊條例》( 第 583 章 ) 註冊為下述技工的人——

(a) 屬水喉工工種分項的註冊熟練技工;

(b) 屬地渠及喉管工 ( 全科 ) 工種分項的註冊熟練技工;或

(c) 屬水喉工工種分項的註冊半熟練技工。

第 2 部

註冊水喉技工 ( 臨時 )

1. 就建造、安裝、保養、更改、修理或拆除消防供水系統而言,或就安裝水錶而言,根據《建造業工人註冊條例》( 第 583 章 ) 註冊為下述技工的人——

(a) 屬水喉工工種分項的註冊熟練技工 ( 臨時 );

(b) 屬地渠及喉管工 ( 全科 ) 工種分項的註冊熟練技工 ( 臨時 );

(c) 屬消防機械裝配工工種分項的註冊熟練技工 ( 臨時 );

(d) 屬水喉工工種分項的註冊半熟練技工 ( 臨時 );或

(e) 屬消防機械裝配工工種分項的註冊半熟練技工( 臨時 )。

2. 就建造、安裝、保養、更改、修理或拆除內部供水系統而言,根據《建造業工人註冊條例》( 第 583 章 ) 註冊為下述技工的人——

(a) 屬水喉工工種分項的註冊熟練技工 ( 臨時 );

(b) 屬地渠及喉管工 ( 全科 ) 工種分項的註冊熟練技工 ( 臨時 );或

(c) 屬水喉工工種分項的註冊半熟練技工 ( 臨時 )。”。

條: 13 公眾街喉 E.R. 1 of 2017 15/02/2017

(1) 水務監督可在任何地方設置公眾街喉,無須收費而向公眾人士供水。

(2) 除獲水務監督書面許可外,任何人不得在公眾街喉取水作住宅用途以外的任何用途。

(3) 任何人違反第(2)款的規定,即屬犯罪。

13A. 指明水管工程的涵義

在本部中——

指明水管工程(specified plumbing works) 指建造、安裝、保養、更改、修理或拆除消防供水系統或內部供水系統。

13B. 何謂“在指示及督導下進行指明水管工程”

就本部而言,在以下情況下,某人即屬在另一人(督導者)的指示及督導下,進行指明水管工程——

(a) 該人在該督導者決定的工作範圍內,按該督導者的指示,進行該指明水管工程;及

(b) 進行該指明水管工程的方法及方式,由該督導者指明。”。

條: 36 逮捕的權力 E.R. 1 of 2017 15/02/2017

(1) 任何由水務監督以書面授權為其代表的公職人員,可逮捕任何他有合理理由懷疑曾犯第29(1)(e)、30、31或32條所訂罪行的人。

(2) 凡公職人員根據第(1)款逮捕任何人,須隨即將該人帶往最近的警署,移交警務人員羈押,而《警隊條例》(第232章)第52條須即時適用。

“36A. 檢控時限

(1) 凡水務監督於某日發現或知悉違反本條例的情況,就該違例事項而提出的檢控,可於在該日翌日開始的6 個月內提出。

(2) 本條不適用於在《2017 年水務設施( 修訂) 條例》(2017

年第  號) 實施日期前發生的違例事項。”。

附表

註冊水喉技工及註冊水喉技工( 臨時)

第1 部

註冊水喉技工

1. 就建造、安裝、保養、更改、修理或拆除消防供水系統而言,或就安裝水錶而言,根據《建造業工人註冊條例》( 第583 章) 註冊為下述技工的人——

註四
Report of the Task Force on

Investigation of Excessive Lead Content in Drinking Water

October 2015

an individual flat in Hong Ching House and Yuet Ching House of KCE and Luen Yat House of KLE2 respectively

and preserved by acidifying with high-purity concentrated nitric acid to pH less than two before delivering to the laboratory for testing of the four metals by the Inductively Coupled Plasma-Mass Spectrometer (ICP-MS)5. 2.4.4 The testing by ICP-MS was based on the United States Environmental Protection Agency Method 200.8. Each water sample was analysed by five measurements in accordance with the instrument setting. Each measurement was performed by repeating the signal measuring procedures for three times. The result of the respective metal content was calculated by taking the average of the five measurements.

2.4.7 The estimated measurement uncertainties (MU) of the testing results for lead, chromium, cadmium and nickel were ±7%, ±7%, ±8% and ±8% respectively at 95% confidence level. For example, if the test result of lead content in a water sample was 0.1mg/L, the result would be within the range of 0.1 ± 0.07mg/L after taking into consideration of MU of the test.

2.8.2 Reaction of lead ions with carbonate ions and hydroxide ions in water may form insoluble lead carbonates or lead hydroxides at or near the surfaces where lead ions are released due to the low solubilities of the carbonates and hydroxides and the relatively higher concentrations of the lead ions under stagnant conditions. The insoluble compounds may deposit locally or be drifted downstream and deposit on other surfaces in contact as alien matters. The formation of lead compounds was identified by Galvanic corrosion is an electrochemical process in which one metal has a greater tendency to lose electrons than another. There are three essential components for galvanic corrosion: two dissimilar metals in electrical contact with one metal as an anode and the other as a cathode, and a medium for ions to move around, i.e. an electrolyte medium. 22 analysis of the deposits cleansed from some of the components of the water supply chains. The test results shown in Annex 2.5 indicated the presence of lead compounds in the deposits which could also release lead into the drinking water by dissolution as lead ions and by suspension as small particles of lead compounds from the deposits. Figure 2.8 (a)-(c) illustrates the process of formation of lead containing deposits and release of lead into drinking water from the deposits.

2.12.2 For the stagnation test, it was conducted by first thoroughly flushing the water supply chain for 15 hours. Water then remained stagnant in the water supply chain and water samples were taken at 0 hour, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 24 hours and 48 hours for determining the lead contents. 2.12.3 Immediately after the 48-hour stagnation test, the flushing test was carried out by taking water samples after flushing for 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 10 minutes and 30 minutes. The results of the stagnation and flushing tests are summarised in Annex 2.8

(a) According to the results of stagnation and flushing tests conducted by the Task Force, the heavy metal contents in water will increase with its stagnation time in the water supply chain if there is leaching of heavy metals from its components. In addition, the test results also indicate that the heavy metal contents in the stagnated water can be reduced substantially after flushing for about two minutes. Therefore, if water has been standing in pipes for a long time (for instance, after several hours of non-use, overnight, over a weekend or after a holiday), the tap should be run for two minutes or longer before using it for drinking or food preparation in order to avoid high concentration of lead in the stagnated water. The flushed water could be saved and used for purposes other than drinking and cooking.

(b) The Authorised Person (AP)17 and the Licensed Plumber (LP)18 needed to submit a list of pipes and terminal fittings to be installed in the inside services to WA before commencement19 of construction.

註五
Guidelines for Drinking-water Quality

FOURTH EDITION

World Health Organization 2011

1.2.10 Plumbing

Significant adverse health effects have been associated with inadequate plumbing systems within public and private buildings arising from poor design, incorrect installation, alterations and inadequate maintenance.

For some materials (e.g. domestic plumbing), assumptions must also account for the relatively high release of some substances for a short period following installation

Important control measures during dismantling and transport of installations include emptying hoses, preferably drying them and storing them so that ingress of contamination is avoided. In all cases, the materials should be approved for use in contact with potable water

If a temporary water supply is used recurrently, it is essential to fully flush the entire system with water containing a higher than normal disinfectant residual before restarting. When

In addition, the system should be disinfected and flushed after maintenance or repairs, and the microbiological quality of the water should be checked, preferably before the system is returned to service.

minimization of dead ends and areas of stagnation, which may be managed by periodic flushing;

Copper concentrations in drinking-water vary widely, with the primary source most often being the corrosion of interior copper plumbing. Levels in running or fully flushed water tend to be low, whereas those in standing or partially flushed water samples are more variable and can be substantially higher (frequently above 1 mg/l). Copper concentrations in treated water often increase during distribution, especially in systems with an acid pH or high-carbonate waters with an alkaline pH

註六
file:///E:/M288.pdf

Preparation of Basic Copper Carbonate Microspheres by Precipitation Method DU Ying-ji1,a ,WANG Li-xian1,b* ,GUO De-hua1,c ,MA Zhu-qiang2 ,SHEN Long2 1 Shanghai Institute of Technology, 100 Haiquan Road, Shanghai 201418, China 2 Shanghai Rongjian Chemical Plant, 269 Chuhua Road, shanghai 201400, China a email:18721526780@163.com, b email:wlx@sit.edu.cn, c email:guodehua2015@163.com Key words: basic copper carbonate; microspheres; particle size; cupric oxide.

Abstract:

Basic copper carbonate [Cu2(OH)2CO3]with sphere-like morphology had been prepared via a direct precipitation route by controlled reaction conditions. Crude materials were cupric chloride solution and sodium carbonate solution. The factors like reaction temperature and reaction pH were studied. Scanning electron microscopy, powder X-ray diffraction, and Fourier transmission infrared spectrometry are used to characterize morphologies, crystal form and structure of the obtained malachite samples, respectively. The result shows: The obtained product is sphere-like malachite. These green basic copper carbonate crystal particles are formed with a diameter of 5.0~6.5 μm, when the temperature keeps about 50 ºC , pH is about 7.0~7.5, and to react for 6h. And it promotes the crystallization of amorphous basic copper carbonate by adding malachite seeds. Cupric oxide can be obtained with the pyrolysis of as-prepared malachite microspheres, and the microspheres and surface microstructures of the malachite are preserved.

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