| With the rapid development of the plant extracts industry in our country,the content of the plant extracts has included not only Chinese herbal medicineindustry, but also more and more extensive relevant industry, therefore muchattention has been paid to the pollution of the plant wastewater treatment and therelevant solutions. Taking vegetable wastewater as an example, its main featuresare as follows，containing a lot of natural organic compositions, most of whichare tannins, also include some sugar, the phenols but not tannins, organic acids,pigments, lignin derivatives and so on. All of these organic compositions arehardly degraded and have certain biological toxicity. So the vegetablewastewater is a kind of organic industry wastewater which is difficult to treat.The traditional anaerobic reactors belong to single-phase anaerobic reactorsin which the toxic substances will produce harm on the microorganism and makethe treatment performance reduce while the Anaerobic baffled reactor(ABR)belongs to two-phase anaerobic reactors which can make hydrolysis acidificationand methanogenesis reaction in different compartments, which has small adverseeffects on microorganism and make the treatment performance high. The hybridanaerobic baffled reactor(HABR) which is fixed three-dimensional packings inthe upper part of the ABR performances better than ABR. The characteristics ofthe start-up of HABR and its treatment of vegetable wastewater as a pretreatmentwere researched in this paper.In this paper, a new HABR was designed on the basis of the ABR, thensome related experimental studies have been done with the reactor, at first it wasstarted up by glucose wastewater, then the microorganism are tamed by tannin,for processing vegetable wastewater at last, the experiment research conclusionsare as follows:(1)The start-up of HABR with glucose wastewater inoculated withanaerobic sludge under the temperature of (34±1)℃and keep the alkalinity ofinfluent above900mg/L(CaCO3) was like this, at first, the feed water concentration was fixed when the HRT was gradually shortened, according to theresults we got that the more appropriate HRT for this reactor is18h; then theHRT was fixed at18h, the influent concentration was increased from1000to2500mg/L gradually. The start-up was completed with38days, Initially, thevolume organic loading rate was3.3kgCOD/(m~3·d) and the COD removal ratewas steady at95%or more. In the whole process of the start-up, the pH, VFAand alkalinity of the effluent showed a certain regularity and stability. We knowthat methane-producing activity of the sludge was gradually recovered from thecoenzyme F420of we monitored.(2)The packing as a biological carrier in the reactor has played a key role inthe fast start-up of the HABR. The main function of the packing was physicalintercepting in high load. It could not only avoid the loss of the sludge, but alsoincrease the effective space of the microbes in the reactor.(3)In the process of the tame with tannin, the influent COD concentrationwas kept at2700mg/L, the HRT was18h, and now the organic load was3.6kgCOD/(m~3·d). The proportion of tannin was increased gradually, its massconcentrations were0.08，0.16，0.24，0.28，0.32，0.4，0.8and1.2g/L separately.The glucose part was gradually reduced at the same time. The process have took36d. In the whole process of domestication, VFA(below6mmol/L), pH(6.6~7.5)and alkalinity (500~1200mg/L) are kept at a stable level. After the domestication,sludge had higher methane-producing activity showed by coenzyme F420.(4)The HABR used to treat the vegetable wastewater had good effects afterthe tame of tannin. For BA light color vegetable wastewater,when the influentconcentration of COD was2000mg/L,the mass concentration was1.8g/L, theremoval rate could achieve80%above, and for the thorns bark tannin extractswastewater at same influent concentration, the removal rate was70%or more.And the HABR could restart in a short time when it treated BA light colorvegetable wastewater, and the activety of the sludge could be recovered soon. |
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