Papermaking · Textile · Printing dyeing
Paper making wastewater treatment plant
一. 設(shè)備簡介
1、 Equipment introduction
造紙污水處理設(shè)備指的是對造紙行業(yè)產(chǎn)生污水的處理方法,造紙廢水主要來自造紙工業(yè)生產(chǎn)中的制漿和抄紙兩個生產(chǎn)過程。制漿、抄紙都排出大量廢水;制漿產(chǎn)生的廢水,污染為嚴(yán)重。洗漿時排出廢水呈黑褐色,稱為黑水,黑水中污染物濃度很高,BOD高達(dá)5—40g/L,含有大量纖維、無機鹽和色素。漂白工序排出的廢水也含有大量的酸堿物質(zhì)。抄紙機排出的廢水,稱為白水,其中含有大量纖維和在生產(chǎn)過程中添加的填料和膠料.
Papermaking wastewater treatment equipment refers to the treatment method of wastewater produced in papermaking industry. Papermaking wastewater mainly comes from the two production processes of pulping and papermaking in papermaking industry. A large amount of wastewater is discharged from pulping and papermaking; The wastewater from pulping is seriously polluted. The effluent from pulp washing is dark brown, which is called black water. The concentration of pollutants in black water is very high, and the BOD is as high as 5-40g / L. it contains a lot of fiber, inorganic salt and pigment. The effluent from bleaching process also contains a lot of acid and alkali. The waste water discharged from paper machine is called white water, which contains a lot of fiber and fillers and binders added in the production process
二. 造紙污水處理方式
2、 Treatment methods of papermaking wastewater
造紙廢水預(yù)處理:
Pretreatment of papermaking wastewater
預(yù)處理工藝主要由格柵、篩網(wǎng)、纖維回收系統(tǒng)、調(diào)節(jié)水量及水質(zhì)等工藝組成。可根據(jù)不同的造紙工業(yè)廢水水質(zhì)采取不同的預(yù)處理手段,去除一部分污染物,改善廢水水質(zhì),使整個廢水處理系統(tǒng)的處理效果達(dá)到。
The pretreatment process is mainly composed of grid, screen, fiber recovery system, regulating water quantity and water quality. According to the different wastewater quality of paper industry, different pretreatment methods can be adopted to remove some pollutants and improve the wastewater quality, so that the treatment effect of the whole wastewater treatment system can be achieved.
造紙廢水主要處理方法:
The main treatment methods of papermaking wastewater are as follows
廢紙造紙廢水的SS、COD濃度較高,COD則由非溶解性COD和溶解性COD兩部分組成,通常非溶解性COD占COD組成總量的大部分,當(dāng)廢水中SS被去除時,絕大部分非溶解性COD同時被去除。廢紙造紙污水中的BOD5值較低,BOD5與COD的比值一般為0.15~0.25,可生化性較差?;炷幚矸椒ㄖ荒苋コ糠諦OD5,絕大部分BOD5的去除主要應(yīng)采用生化方法解決。
The concentration of SS and COD in waste paper-making wastewater is high, and COD is composed of insoluble COD and soluble COD. Generally, the insoluble cod accounts for most of the total COD. When SS is removed, most of the insoluble cod is removed at the same time. The ratio of BOD5 to cod is generally 0.15-0.25, and the biodegradability is poor. Coagulation treatment can only remove part of BOD5, most of which should be solved by biochemical method.
(1)采用氣浮或沉淀方法。通過投加混凝劑,可去除絕大部分SS,同時去除大部分非溶解性COD及部分溶解性COD和BOD5。其典型的處理工藝流程如下:
(1) Air floatation or precipitation method is adopted. By adding coagulant, most SS, most insoluble cod, part soluble COD and BOD5 can be removed. The typical treatment process is as follows:
污水→篩網(wǎng)→集水池→氣浮或沉淀→排放
Sewage → screen → sump → flotation or sedimentation → discharge
氣浮和沉淀均為物化處理方法,處理效果與選用的設(shè)備、工藝參數(shù)、混凝劑等有關(guān),其COD去除率一般高于制漿中段水的COD去除率,通常能達(dá)到70%~85%。對噸紙污水排放量>150m3、濃度較低的中小型廢紙造紙企業(yè),通過氣浮或沉淀處理,出水水質(zhì)指標(biāo)可達(dá)到或接近排放標(biāo)準(zhǔn)。
Both flotation and sedimentation are physicochemical treatment methods, and the treatment effect is related to the selected equipment, process parameters, coagulant, etc. the COD removal rate of flotation and sedimentation is generally higher than that of middle stage water, which can reach 70% - 85%. The effluent quality of small and medium-sized waste paper-making enterprises with discharge capacity of more than 150m3 per ton of paper and low concentration can reach or approach the discharge standard through air flotation or sedimentation treatment.
氣浮法和沉淀法工藝的對比分析:
Comparison and analysis of air flotation and precipitation processes
氣浮法
Air flotation
沉淀法
Precipitation method
優(yōu)點
advantage
缺點
shortcoming
優(yōu)點
advantage
缺點
shortcoming
1.處理效果穩(wěn)定、可靠
1. The treatment effect is stable and reliable
1.設(shè)備費用較高
1. The cost of equipment is high
1.處理方法成熟、穩(wěn)定
1. The treatment method is mature and stable
1.占地較大
1. It covers a large area
2.占地面積小
2. Small area
2.運行電耗略高
2. The operation power consumption is slightly higher
2.電耗較低
2. Low power consumption
2.污泥需經(jīng)濃縮后脫水
2. Sludge should be dewatered after thickening
3.污泥量少,易于脫水
3. Less sludge, easy to dehydrate
3.操作較簡單
3. The operation is simple
4.土建費用低
4. Low cost of civil engineering
近幾年來,在氣浮法中淺層氣浮異軍突起。淺層氣浮具有水力停留時間短(<5min)、池體水深淺(500mm)、處理效果好等優(yōu)點。它應(yīng)用淺池理論和“零速度”原理,徹底改變了傳統(tǒng)推流式氣浮池的進(jìn)出水及污泥分離方式,污水在氣浮池中處于相對靜止?fàn)顟B(tài),微氣泡吸附污泥后可垂直向上浮起,固形物上浮速度為4~10cm/min,可在短時間內(nèi)獲得優(yōu)質(zhì)出水,其SS、COD去除率可略高于沉淀法,對中型規(guī)模的污水處理有其一定的性。
In recent years, shallow air floatation has become a new force in air floatation. Shallow air flotation has the advantages of short HRT (< 5min), shallow water depth (500mm) and good treatment effect. Using the shallow pool theory and "zero velocity" principle, it completely changes the traditional plug flow air flotation tank's inlet and outlet water and sludge separation mode. The sewage is in a relatively static state in the air flotation tank, and the micro bubbles can float up vertically after adsorbing the sludge. The solid floating speed is 4-10cm / min, and the high-quality effluent can be obtained in a short time. The removal rates of SS and COD are slightly higher than those of the sedimentation method, It has certain applicability for medium-sized sewage treatment.
(2)物化與生化處理相結(jié)合。對于造紙廢水排放量較低、廢水含COD較高的大中型廢紙造紙企業(yè),期望通過單級氣浮或沉淀的物化方法達(dá)到一級排放標(biāo)準(zhǔn)有較大的難度,因為可溶性COD、BOD5主要需通過生化方法才能有效去除。
(2) The combination of physicochemical and biochemical treatment. For large and medium-sized waste paper enterprises with low discharge and high COD content, it is difficult to reach the first-class discharge standard by single-stage air flotation or precipitation, because soluble COD and BOD5 can be effectively removed by biochemical methods.
當(dāng)執(zhí)行COD≤100mg/L的排放標(biāo)準(zhǔn)時,原水COD濃度不宜超過600~800mg/L;當(dāng)執(zhí)行COD≤150mg/L的排放標(biāo)準(zhǔn)時,原COD濃度不宜超過800~1000mg/L。因此,在原水SS和COD濃度較高時,應(yīng)在一級物化處理之后接生化方法處理,使處理出水終達(dá)到排放標(biāo)準(zhǔn)的要求。物化加生化處理方法的典型工藝流程如下:
When the discharge standard of COD ≤ 100mg / L is implemented, the COD concentration of raw water should not exceed 600 ~ 800mg / L; When the discharge standard of COD ≤ 150mg / L is implemented, the original COD concentration should not exceed 800 ~ 1000mg / L. Therefore, when the concentration of SS and COD in raw water is high, the first stage physicochemical treatment should be followed by biochemical treatment to make the treated effluent meet the discharge standard. The typical process flow of physicochemical plus biochemical treatment method is as follows:
污水→篩網(wǎng)→調(diào)節(jié)→沉淀或氣浮→A/O或接觸氧化→二沉池→排放
Sewage → screen → adjustment → sedimentation or flotation → A / O or contact oxidation → secondary sedimentation tank → discharge
A/O(缺氧—好氧)處理工藝,通過缺氧段的微生物選擇作用,只是對物進(jìn)行吸附,吸附在微生物體的物則在好氧段被氧化分解。因此A段停留時間短,約在40~60min。
In a / O (anoxic aerobic) treatment process, only the adsorbate is adsorbed through the selective action of microorganism in anoxic section, while the adsorbate is oxidized and decomposed in aerobic section. Therefore, the residence time of stage a is short, about 40-60min.
由于A段微生物的篩選和對物的吸附作用,能有效地抑制O段絲狀菌生長,控制污泥膨脹。當(dāng)污水經(jīng)過混凝沉淀或氣浮處理后,A/O工藝的負(fù)荷為0.5kgCOD/(kgMLSS•d)時,其COD去除率可達(dá)90%左右。
Due to the screening of microorganisms in stage a and the adsorption of pollutants, it can effectively inhibit the growth of filamentous bacteria in stage o and control sludge bulking. When the load of a / O process is 0.5 kgcod / (kgmlss · d), the removal rate of COD can reach about 90%.
生物接觸氧化法具有掛膜快、無污泥回流系統(tǒng)、無污泥膨脹危害、日常運行管理容易等優(yōu)點,在中小型污水處理中應(yīng)用較多。
Biological contact oxidation process is widely used in small and medium-sized wastewater treatment due to its advantages of fast film formation, no sludge return system, no harm of sludge bulking and easy daily operation and management.
三.常見造紙污水處理工藝流程圖
3、 Process flow chart of common papermaking wastewater treatment
四.造紙污水處理設(shè)備特點
4、 Characteristics of papermaking wastewater treatment equipment
1、造紙污水處理設(shè)備經(jīng)碳鋼防腐處理或不銹鋼構(gòu)件,現(xiàn)場拼接組合而成。重量輕巧,易于運輸,方便安裝;
1. The paper-making wastewater treatment equipment is made of carbon steel anti-corrosion treatment or stainless steel components and assembled on site. Light weight, easy to transport, easy to install;
2、采用玻璃鋼、碳鋼、不銹鋼防腐結(jié)構(gòu),具有耐腐蝕、抗老化等優(yōu)良特性,使用壽命長達(dá)60 年以上;
2, adopt FRP, carbon steel and stainless steel anticorrosive structure, with corrosion resistance, anti-aging and other excellent characteristics, the service life is longer than 60 years.
3、放置于地表以下,造紙污水處理設(shè)備上面的地表可作為綠化或其他用地,不需要建房及采暖、保溫。限度的實現(xiàn)了系統(tǒng)的集成,減少占地面積;
3. It can be used for greening or other purposes without building houses, heating and heat preservation. The integration of the system is limited and the floor space is reduced;
4、,無噪聲,無異味,減少二次污染;
4. No noise, no odor, reduce secondary pollution;
5、不受造紙污水量的限制,機動靈活,可單個使用,也可多個聯(lián)合使用。
5. It is not limited by the amount of papermaking wastewater, flexible, and can be used individually or in combination.
6、整個造紙污水設(shè)備處理系統(tǒng)配有PLC全自動電氣控制系統(tǒng)和設(shè)備故障報警系統(tǒng),運行安全可靠,平時一般不需要專人管理,只需適時地對造紙污水處理設(shè)備進(jìn)行維護(hù)和保養(yǎng),管理費用小。
6. The whole paper-making wastewater treatment system is equipped with PLC automatic electrical control system and equipment fault alarm system, which is safe and reliable in operation. Usually, it does not need to be managed by a special person, but only needs to timely maintain the paper-making wastewater treatment equipment, so the management cost is small.