Study On Treatment Of Furfural Wastewater With Anaerobic Baffled Reactor

Furfural is a chemical raw materials which has been used widely, it couldn't be synthesize by petrochemical, however is only made of fiber of plant, so the production of furfural is utilization of waste which meets the conception of continued development and is meaningful for the development of industry and economy. Furfural wastewater that is from production of furfural belongs to high concentration organic wastewater, it contains amount of acid, the content of acetic acid, aldehyde and chaff is 1%～2.5%. Furfural wastewater is khaki, turbid. Because of the different processes of productions, the quality of the wastewater is also different from each other. The wastewater in the research is from Shuanglong factory, COD_cr of influent is 12000 mg/L～25000mg/L, pH value is 2.10～2.60, BOD₅/COD_cr is 0.33～0.46. So with the development of industry of furfural production, the pollutions are becoming more and more serious and arouse the attention of society and many environment protection departments.The methods of treating furfural wastewater conclude chemical process and biological treatment. In overseas area, it's usually used bio -logical treatment, e.g. anaerobic filter and defined mixed culture. Besides, in our country it's usually used chemical process, e.g. neutra liza -tion, extraction-distillation, and electro dialysis-extraction-distillation.McCarty in Stanford University put forward Anaerobic Baffled Reactor which was a new anaerobic reactor. Its compartments make different microbial populations develop under their optimal conditions. ABR has the high sludge concentration. Acidogenic populations are in the front compartments, and can improve biodegradability of wastewater. The release of hydrogen ensures that the phase of methanation is normal. Known from these, microbial populations in different compartments are different from each other.Because of its hydrodynamic characteristic and other excellences, more and more people pay attention to ABR, but the study of ABR is still in the stage of lab. Therefore there is need to study deeply. The research chooses ABR to dispose furfural wastewater in order to supply parameters for practice engineering.The research concluded following parts:1. At the ambient temperature, started the Anaerobic Baffled Reactor and supervised the content of COD_cr, VFA and alkalinity.2. Compared the effects of different parameters. Study the COD_cr removal efficiency and the concentration of VFA and alkalinity on different conditions.3. Observe the microbial populations of compartments.The results indicated:1. At the beginning of the experiment, the concentration of CODcr of influent was 2500mg/L, when the CODcr removal efficien -cy was steady, about 86.9%, shortened the HRT, CODcr removal effi -ciency was still above 85.0%. When raised the content of CODcr of influent, CODcr removal efficiency begun to decline, at the moment, OLR was 6.56 KgCODcr/ (m³Â·d) . pH value and the concentration of alkalinity had been increasing all the time in the period. 2. When the average content of CODcr of influent was 13000 mg/L, HRT was 48h and the OLR was 6.56 KgCODcr/ (m³Â·d) , CODcr removal efficiency was above 80%. CODcr removal efficien -cy had been declining when the content of CODcr of influent increa -sed, but the organic loading rate was increasing.3. The first three compartments made a great contribution to CODcr removal efficiency, and the quality of effluent was held steady by the compartments at the back .With the wastewater going trough the anaerobic sludge, the organic was degraded. The concentration of CODcr and VFA continuously reduced, and alkalinity was increasing, these showed that the sludge distributed even in the reactor and lived in suitable surroundings.4. The results indicated that the ABR had a good resistibility for impact. When the concentration and volume of influent changed, the CODcr removal efficiency was still high, and became steady within tow HRTs.5. In domestication period, small bubbles which adhered to the surface of sludge caused the sludge to float. The small and aging sludge was removed which making the concentration of the SS increase. In the process of experiment, the activity of sludge declined firstly and then increased, SVI was about 15% at the end.6. With ABR disposing furfural wastewater, the concentration of CODcr of effluent was still high, about 2500 mg/L, so other treatments were necessary before draining. The latter compartments which were not very useful could be taken out in order to economize the cost.