摘要:為了解決核桃殼過濾罐反沖洗結束后前期出水水質不達標問題,通過對核桃殼過濾罐外部工藝管線流程進行調整,使核桃殼濾料在反洗結束后快速成(cheng)床,并(bing)在現場試驗中(zhong)證明快速成(cheng)床式(shi)反沖洗方式(shi)縮短(duan)了濾(lv)料的(de)成(cheng)床時間(jian):由常規的(de)2~2.5h縮短(duan)至0.5~0.75h,并(bing)有效延(yan)長核(he)桃(tao)殼過(guo)濾(lv)器過(guo)濾(lv)周(zhou)期內(nei)水質(zhi)達標(biao)的(de)時間(jian),能夠提高過(guo)濾(lv)后水質(zhi)指標(biao)。
核(he)桃(tao)(tao)殼(ke)(ke)(ke)過濾(lv)(lv)(lv)罐(guan)廣(guang)泛用于(yu)油(you)田污水(shui)(shui)普(pu)通站和深(shen)度(du)站過濾(lv)(lv)(lv)處(chu)理工藝中油(you)和懸(xuan)浮(fu)物的去除(chu),為了保證過濾(lv)(lv)(lv)效(xiao)果,要(yao)定(ding)期對罐(guan)內核(he)桃(tao)(tao)殼(ke)(ke)(ke)濾(lv)(lv)(lv)料(liao)(liao)進(jin)(jin)行(xing)(xing)反(fan)沖洗。由于(yu)核(he)桃(tao)(tao)殼(ke)(ke)(ke)濾(lv)(lv)(lv)料(liao)(liao)為輕質濾(lv)(lv)(lv)料(liao)(liao),在(zai)(zai)反(fan)沖洗過程中常(chang)采用槳(jiang)攪(jiao)拌方式對核(he)桃(tao)(tao)殼(ke)(ke)(ke)濾(lv)(lv)(lv)料(liao)(liao)進(jin)(jin)行(xing)(xing)再生,因此濾(lv)(lv)(lv)料(liao)(liao)在(zai)(zai)反(fan)沖洗過程中膨化,在(zai)(zai)反(fan)沖洗結(jie)束后,核(he)桃(tao)(tao)殼(ke)(ke)(ke)濾(lv)(lv)(lv)料(liao)(liao)尚未被(bei)(bei)壓實,濾(lv)(lv)(lv)料(liao)(liao)之間孔(kong)隙較大,反(fan)沖洗結(jie)束后過濾(lv)(lv)(lv)初期過濾(lv)(lv)(lv)出水(shui)(shui)水(shui)(shui)質較差,隨(sui)著過濾(lv)(lv)(lv)的進(jin)(jin)行(xing)(xing),核(he)桃(tao)(tao)殼(ke)(ke)(ke)濾(lv)(lv)(lv)料(liao)(liao)逐漸(jian)被(bei)(bei)壓實,過濾(lv)(lv)(lv)出水(shui)(shui)水(shui)(shui)質才可以(yi)達到過濾(lv)(lv)(lv)罐(guan)要(yao)求出水(shui)(shui)標(biao)準(zhun)。
為了解決核(he)桃殼(ke)過(guo)(guo)濾(lv)(lv)罐反沖洗結束后(hou)前期出水(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)質不達標(biao)問題,保證核(he)桃殼(ke)過(guo)(guo)濾(lv)(lv)罐反洗后(hou)的出水(shui)(shui)(shui)(shui)效果(guo),可將(jiang)前期不達標(biao)的水(shui)(shui)(shui)(shui)排入回(hui)收(shou)水(shui)(shui)(shui)(shui)池(chi),不進入濾(lv)(lv)后(hou)水(shui)(shui)(shui)(shui)系統(tong),避免對過(guo)(guo)濾(lv)(lv)后(hou)水(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)質造成(cheng)影(ying)響;由于(yu)普通核(he)桃殼(ke)過(guo)(guo)濾(lv)(lv)器成(cheng)床(chuang)時間較長,導致進人回(hui)收(shou)水(shui)(shui)(shui)(shui)池(chi)的水(shui)(shui)(shui)(shui)量(liang)偏大,因此回(hui)收(shou)水(shui)(shui)(shui)(shui)池(chi)的容積需(xu)要增加(jia)大,同時回(hui)收(shou)水(shui)(shui)(shui)(shui)池(chi)水(shui)(shui)(shui)(shui)再(zai)進入處理系統(tong),造成(cheng)系統(tong)負(fu)荷增加(jia)。因此這種方式(shi)不可取(qu)。
通過(guo)對(dui)核(he)桃(tao)殼過(guo)濾(lv)(lv)罐(guan)外部工藝管(guan)(guan)線進(jin)行(xing)改(gai)(gai)進(jin),使(shi)反(fan)洗(xi)(xi)(xi)(xi)(xi)后(hou)的濾(lv)(lv)料(liao)(liao)快(kuai)速成(cheng)(cheng)(cheng)床,保(bao)證反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)后(hou)過(guo)濾(lv)(lv)出(chu)水(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)質短期(qi)內(nei)能夠穩定達標。對(dui)核(he)桃(tao)殼過(guo)濾(lv)(lv)罐(guan)反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)進(jin)出(chu)水(shui)(shui)(shui)(shui)管(guan)(guan)路(lu)進(jin)行(xing)改(gai)(gai)進(jin),在反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)進(jin)出(chu)水(shui)(shui)(shui)(shui)管(guan)(guan)路(lu)上增加連通閥(fa)門。原反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)模式為在30min內(nei)自下而上的對(dui)核(he)桃(tao)殼濾(lv)(lv)料(liao)(liao)進(jin)行(xing)攪拌、沖(chong)洗(xi)(xi)(xi)(xi)(xi),然后(hou)通過(guo)正濾(lv)(lv)對(dui)濾(lv)(lv)料(liao)(liao)進(jin)行(xing)自然壓實成(cheng)(cheng)(cheng)床;改(gai)(gai)進(jin)的反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)模式是前25min保(bao)持原反(fan)洗(xi)(xi)(xi)(xi)(xi)模式,后(hou)5min關(guan)閉反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)進(jin)、出(chu)水(shui)(shui)(shui)(shui)閥(fa)門,打開快(kuai)速成(cheng)(cheng)(cheng)床進(jin)、出(chu)水(shui)(shui)(shui)(shui)閥(fa)門,利用反(fan)沖(chong)洗(xi)(xi)(xi)(xi)(xi)水(shui)(shui)(shui)(shui)再對(dui)核(he)桃(tao)殼濾(lv)(lv)料(liao)(liao)進(jin)行(xing)自上而下的大(da)強度水(shui)(shui)(shui)(shui)力壓實,使(shi)濾(lv)(lv)料(liao)(liao)快(kuai)速成(cheng)(cheng)(cheng)床。
為了(le)對(dui)比(bi)普(pu)通(tong)(tong)式(shi)反沖(chong)洗方(fang)式(shi)和快(kuai)速(su)成(cheng)(cheng)(cheng)床(chuang)式(shi)反沖(chong)洗方(fang)式(shi)下,核(he)桃殼濾(lv)料的成(cheng)(cheng)(cheng)床(chuang)時(shi)間及過(guo)濾(lv)后(hou)出(chu)水效果(guo),波濤(tao)凈水材料廠(chang)進行了(le)現(xian)場(chang)小試(shi)試(shi)驗(yan),并在(zai)北五污水站進行了(le)現(xian)場(chang)試(shi)驗(yan),通(tong)(tong)過(guo)過(guo)濾(lv)后(hou)水質變化趨勢(shi)確(que)定核(he)桃殼濾(lv)料成(cheng)(cheng)(cheng)床(chuang)時(shi)間。普(pu)通(tong)(tong)攪拌式(shi)與快(kuai)速(su)成(cheng)(cheng)(cheng)床(chuang)反洗工藝參數(shu)對(dui)比(bi)見表1。
表1 普通(tong)攪拌式(shi)與(yu)快速成(cheng)床式(shi)反(fan)洗(xi)工藝參數(shu)對比
反洗形式 | 普通攪拌式 | 快速成床式 |
攪拌時間/min | 15 | 15 |
攪拌時水力沖洗強度/L·(m2·s)-1 | 3 | 3 |
攪拌停止后水力沖洗強度/L·(m2·s)-1 | 7 | 7 |
攪拌停止后水力沖洗時間/min | 15 | 10 |
攪拌停止后由上至下水力沖洗強度//L·(m2·s)-1 | - | 9 |
攪拌停止后由上至下水力沖洗時間/min | - | 5 |
(1) 現場小試出水(shui)效果對比
對(dui)(dui)兩(liang)種反沖洗(xi)模式(shi)下過(guo)濾初期(qi)出(chu)水效(xiao)果對(dui)(dui)比可知,普通反沖洗(xi)后(hou)2~2.5h懸浮物達標(biao)(biao)且(qie)趨于(yu)(yu)穩定(ding);快(kuai)速(su)成床式(shi)反沖洗(xi)后(hou)懸浮物30min達標(biao)(biao),45min后(hou)趨于(yu)(yu)穩定(ding)。由(you)過(guo)濾后(hou)水質達標(biao)(biao)且(qie)趨于(yu)(yu)穩定(ding)的時間判斷(duan),快(kuai)速(su)成床式(shi)反沖洗(xi)方(fang)式(shi)縮短成床時間近2h。
(2) 現(xian)場試驗出水效(xiao)果對比(bi)
現場試驗對比兩種模式下的出水效果見圖1。
綜上所述,快速成(cheng)床式反(fan)沖洗方式可將濾料成(cheng)床時間由(you)常(chang)規的2~2.5h縮短至0.5~0.75h,并有效延長核桃(tao)殼過(guo)濾器(qi)過(guo)濾周期(qi)內水(shui)質達標的時間,能夠提高過(guo)濾后(hou)水(shui)質指標,與現場小試結果相符。