一(yi)、裝(zhuang)置(zhi)簡(jian)介(jie)


  氯堿(jian)工(gong)(gong)(gong)業作(zuo)為衡(heng)量國家化(hua)工(gong)(gong)(gong)行業發(fa)展的(de)(de)(de)重要(yao)指標,廣泛應用(yong)于輕工(gong)(gong)(gong)業、紡織工(gong)(gong)(gong)業、冶(ye)金工(gong)(gong)(gong)業、石(shi)油化(hua)學工(gong)(gong)(gong)業以(yi)及公(gong)用(yong)事業。氯堿(jian)的(de)(de)(de)生(sheng)產(chan)工(gong)(gong)(gong)藝一(yi)般分為苛化(hua)法(fa)、隔(ge)膜法(fa)、水(shui)銀法(fa)及離子(zi)膜法(fa)。離子(zi)膜制(zhi)堿(jian)法(fa)從20世紀80年代開始發(fa)展,現已成(cheng)為我國新建燒堿(jian)工(gong)(gong)(gong)廠(chang)中最廣泛應用(yong)的(de)(de)(de)工(gong)(gong)(gong)藝。其工(gong)(gong)(gong)藝流(liu)程(cheng)是通過電解食鹽(yan)水(shui)生(sheng)產(chan)燒堿(jian)和氯氣、氫氣,產(chan)品(pin)作(zuo)為其他化(hua)工(gong)(gong)(gong)產(chan)品(pin)的(de)(de)(de)生(sheng)產(chan)原料(liao)。以(yi)下(xia)以(yi)離子(zi)膜制(zhi)堿(jian)的(de)(de)(de)工(gong)(gong)(gong)藝裝(zhuang)置為例介紹(shao)。


二(er)、離子膜氯(lv)堿裝置的(de)工藝(yi)及特點


  離子膜氯堿裝置工藝流程示(shi)意(yi)圖如圖2.37所示(shi)。整(zheng)個(ge)裝置大致可劃分為(wei)一次(ci)鹽水(shui)和(he)二次(ci)鹽水(shui)精(jing)制(zhi)、電解(jie)單(dan)元(yuan)、淡鹽水(shui)脫氯、氫氣處理(li)及(ji)壓縮、氯氣處理(li)及(ji)壓縮、氯氣液化(hua)、鹽酸合成及(ji)堿蒸發單(dan)元(yuan)。


37.jpg


  以(yi)原(yuan)鹽(yan)(yan)(yan)、鹵水(shui)(shui)作為(wei)原(yuan)料(liao)(liao),通(tong)(tong)過(guo)(guo)一(yi)次鹽(yan)(yan)(yan)水(shui)(shui)膜過(guo)(guo)濾(lv),將鹽(yan)(yan)(yan)水(shui)(shui)中大分子有機物分解(jie)(jie)成小分子,并初步去除。再經(jing)(jing)過(guo)(guo)二(er)次鹽(yan)(yan)(yan)水(shui)(shui)的(de)(de)(de)螯合(he)樹脂塔,進一(yi)步除去其(qi)中的(de)(de)(de)鈣、鎂等金屬離子及懸浮物后。將鹽(yan)(yan)(yan)水(shui)(shui)加入(ru)(ru)離子膜電解(jie)(jie)槽(cao)的(de)(de)(de)陽極(ji)室(shi)(shi),與此同時,純水(shui)(shui)和堿(jian)(jian)(jian)液(ye)(ye)一(yi)同進入(ru)(ru)陰極(ji)室(shi)(shi)。電解(jie)(jie)槽(cao)通(tong)(tong)入(ru)(ru)直(zhi)流電后,在陽極(ji)室(shi)(shi)產(chan)生氯氣(qi)(qi)和含氯淡鹽(yan)(yan)(yan)水(shui)(shui),經(jing)(jing)過(guo)(guo)分離器分離,氯氣(qi)(qi)輸(shu)送到氯氣(qi)(qi)處(chu)理(li)及壓縮單(dan)元(yuan)。在電解(jie)(jie)槽(cao)的(de)(de)(de)陰極(ji)室(shi)(shi)產(chan)生氫氣(qi)(qi)和液(ye)(ye)堿(jian)(jian)(jian)。同樣經(jing)(jing)過(guo)(guo)分離器,氫氣(qi)(qi)輸(shu)送到氫氣(qi)(qi)處(chu)理(li)及壓縮單(dan)元(yuan),堿(jian)(jian)(jian)液(ye)(ye)可(ke)以(yi)作為(wei)商品出售(shou),也可(ke)以(yi)送到堿(jian)(jian)(jian)蒸發單(dan)元(yuan),使(shi)(shi)其(qi)濃縮成50%的(de)(de)(de)堿(jian)(jian)(jian)液(ye)(ye)。電解(jie)(jie)產(chan)生的(de)(de)(de)濕氯氣(qi)(qi)經(jing)(jing)過(guo)(guo)洗(xi)滌、干燥、壓縮后,送往下游作為(wei)原(yuan)料(liao)(liao)使(shi)(shi)用,或通(tong)(tong)過(guo)(guo)冷介質(zhi)降溫液(ye)(ye)化,形成液(ye)(ye)氯存(cun)入(ru)(ru)儲槽(cao);未液(ye)(ye)化的(de)(de)(de)氯氣(qi)(qi)與氫氣(qi)(qi)壓縮單(dan)元(yuan)過(guo)(guo)來(lai)的(de)(de)(de)氫氣(qi)(qi)用于合(he)成氯化氫氣(qi)(qi)體或鹽(yan)(yan)(yan)酸。


三、主要工(gong)藝(yi)介質(zhi)


  氯堿裝置的工藝介質中包含了強酸(如氯氣、氯化氫等)、強堿(如氫氧化鈉等)、氫氣等具有腐蝕性強、易燃爆、有毒有害的介質。其中電解單元的進料鹽水對鑄鐵、碳鋼、不銹鋼材料有不同程度的腐蝕。電解后的淡鹽水中存有游離氯等介質,會加劇對設備、管道材料的腐蝕。因此,在鹽水管道中鋼襯膠、鋼襯塑、塑料閥門的運用較為廣泛。裝置的產品氯氣是一種有毒氣體,逸散性強。同時氯的化學性質很活潑,在一定條件下能與很多金屬及非金屬發生反應。尤其在有水的情況下,氯氣與水反應生成鹽酸和次氯酸。次氯酸受熱及光等的作用易分解出初生態氧并生成鹽酸,初生態氧又是一種強氧化劑。因此,在氯堿裝置中濕氯氣、干氯氣及液氯的危害性最大。


四、氯堿裝置的配管(guan)設計


  主要是對塔、罐、泵、壓縮機等設(she)備的配管(guan)設(she)計。