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    Please use this identifier to cite or link to this item: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/88148


    Title: 焚化飛灰以機械研磨技術進行鉛穩定及改良膠體膠結性作為水泥掺料之研究
    Other Titles: Preparation of cement admixture with MSWI ash by mechanical milling technology for Pb stabilization and cementitious modification
    Authors: 陳政綱;Chen, Cheng-Gang
    Contributors: 淡江大學水資源及環境工程學系博士班
    高思懷
    Keywords: 焚化飛灰;機械研磨;氯離子穩定;無機膠體;MSWI fly ash;Mechanical milling;Stabilize chloride ion;inorganic gel
    Date: 2013
    Issue Date: 2013-04-13 12:02:58 (UTC+8)
    Abstract: 都市垃圾焚化飛灰經過水萃處理程序之後,可去除大量的溶解性的鹽類,對
    於後續再利用之產品的穩定性有相當顯著之成效。而水萃後的飛灰經由機械研磨
    處理程序後,顯示出相當低的重金屬溶出效果,證明具有穩定重金屬的效果。而
    研磨後的水萃反應灰(研磨灰)在取代部分市售水泥製成水泥漿體後,顯示具有卜
    作嵐性質。本研究利用機械研磨使焚化飛灰的物理與化學性質同時轉變,降低重
    金屬移動性,搭配鹼活化促進無機膠體的產生,掺配於市售水泥,達到無害化及
    資源化之目標。
    實驗以水、不同濃度之磷酸(0.002 M、0.2 M PO4
    3-)、不同濃度之氫氧化鈉(1M、
    5M)為鹼液,研磨時間設定為0.5、1、24、96 小時,水泥漿體養護時間為0.35、
    0.38、0.45、0.55,漿體養護時間為1、3、7、28 天。以ICP、粒徑分析儀、比表
    面積儀、壓汞分析儀、X 光繞射儀、核磁共振儀等進行分析。
    焚化飛灰經研磨96 小時後發生無晶序化,使重金屬溶出降至接近儀器偵測極
    限。加入研磨飛灰的水泥漿體其膠體孔隙與毛細孔隙含量比純水泥漿體高出許
    多,形成的漿體較緻密,以NMR 分析後發現C-S-H 聚合度提升,抗壓強度與市
    售水泥相比顯著提升,由此可證明長時間研磨的焚化飛灰有助於加強水化反應與
    促進卜作嵐反應的進行。
    當以0.2 M 磷酸研磨液進行研磨時,研磨時間小於1 小時即產生許多磷酸鈣
    結晶 (HAp, TCP, TTCP),然而可解離的磷酸鈣化合物及過多的PO4
    3-殘留,將消
    耗水泥中的氫氧化鈣,經96 小時研磨後,降低水泥強度的效果大於研磨提升水泥
    強度的效果,導致漿體抗壓強度較市售水泥漿體為低。以0.002 M 磷酸進行時,
    由於研磨灰中產生大量的TTCP,遇水解離成HAp 與氫氧化鈣,然而長時間研磨
    所產生的卜作嵐反應造成7 天與28 天抗壓強度仍大於OPC。
    以不同偏高嶺土調配比進行研磨活化時(1 M 氫氧化鈉、24 小時),發現鹼液
    濃度的不足,未能將矽酸鹽溶出。研磨活化所產生的化合物可進行離子交換反應,
    達到穩定重金屬的效果。然而當鹼液濃度提高時(5 M 氫氧化鈉),則變成由活化膠
    體與重金屬離子進行接合,由於鍵結強度較弱,研磨造成溶出僅略為增加,此外,
    高濃度氫氧化鈉則會對水化反應造成負面的影響。
    利用5 M 氫氧化鈉搭配煆燒淨水污泥進行研磨活化,水萃反應灰調配量較高
    時,會產生穩定的氯離子結晶,調配量較低時,則產生膠體型態以物理穩定機制
    結合氯離子,加入水泥漿體卻使得穩定性較差,可知活化粉形成結構較弱的膠體
    反而不利於水泥早期反應結合氯離子。以水為研磨液時,產生許多類似Friedel’s
    salt 結構,因而有顯著的化學穩定性能,在7 天齡期中水泥漿體即有相當優良的
    氯離子穩定效果。以無機膠體形態掺配於水泥中,其氯離子的穩定型態和反應過
    程和傳統水泥大不相同。
    This study used mechanical milling to change physical and chemical properties of
    municipal solid waste incinerator (MSWI) fly ash. The mobility of heavy metals would be
    reduced by mechanical milling and the amount of inorganic gelwould be also promoted by
    alkali activation of the MSWI fly ash. After mechanical milling and alkali activation
    processes, the MSWI fly ash can achieve the aim of detoxification and recovery, and can
    be a good substitute of Type I ordinary Portland cement (OPC).
    The crystal structure of MSWI fly ash was destroyed and became the amorphous
    phase after milling 96 h. At the same time, the leaching concentration of the heavy metals
    of milled fly ash could be decreased below the detection limit. The paste which partial
    substituted the OPC by the milled fly ash would increase the amount of gel pores and
    middle-size pores, and led the paste to become denser than OPC paste. The results of the
    nuclear magnetic resonance Spectrometer (NMR) test indicated that the milled fly ash
    can not only increase the amount of C-S-H gel which is caused by the higher hydration
    reaction, but also can accelerate the pozzolanic reaction. Based on these results, the
    compressive strength of the paste could rise up in all of the curing times.
    By 0.2 M PO4
    3- of milling solution and 1 h milling time, the calcium phosphate of
    hydroxyapatite (HAp), tricalcium phosphate (TCP) and tetracalcium phosphate (TTCP)
    would be produced. However, the dissolution of calcium phosphate compounds and
    excessive PO4
    3- remained in the milled ash, which made the calcium hydroxide of paste be
    consumed. This result indicate that the milled fly ash by PO4
    3- caused the negative impact
    of the compressive strength of the milled fly ash paste greater than the positive impact,
    and led the compressive strength lower than the OPC paste.
    The milled fly ash with 0.002 M PO4
    3- would produce a lot of TTCP when it partial
    substituted OPC paste, which the TTCP would react with water to produce HAp and
    calcium hydroxide. In addition, the effect of the pozzolanic reaction premature generated
    by 96 h of milling time still appears and the compressive strength of the milled fly ash
    paste after 7 days and 28 days of curing also higher than the OPC paste.
    The effect of metakaolin and washed fly ash on a different mixing ratio by
    mechanical milling activation (1 M NaOH , 24 h) was evaluated. The results show 1 M
    NaOH of milling solution was lack of alkali concentration, thus it could not dissolute the
    silicate of metakaolin. The compounds produced by metakaolin after mechanical milling
    activation could conduct an ions exchange of heavy metal and achieve the stabilization of
    heavy metal. When the alkali concentration increased to 5 M, heavy metal would bond
    with the activated gel. Due to the bonding strength is weak, so the leaching concentration
    of heavy metal was slightly increased. In addition, the high concentration of sodium
    hydroxide would cause significant negative influence on the hydration reaction.
    The milling activation was conducted in 5M of NaOH with the water treatment plant
    sludge after calcination. The results show that the stabilized chloride crystallization would
    be increased when the amount of the extracted fly ash was increased. Nevertheless, when
    the amount of the extracted fly ash was decreased, the type of the bound with chloride ion
    was the physical stability mechanism, which would lead to poor stability of the paste.
    From above statement, the milled activated fly ash would form a gel of weak structure for
    binding with chloride ion and was not conducive to stabilize chloride for the paste in the
    early curing time. When the water was the milling solution, it would generate many
    similar Friedel’s salt structure which caused the effect of observably chemical stability.
    The excellent of the effect of stabilize chloride ion for the paste would be appeared after 7
    days of curing. The stabilization and reaction mechanism of chloride ion in the inorganic
    gel is difference with traditional cement evidently.
    Appears in Collections:[水資源及環境工程學系暨研究所] 學位論文

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