亲水性聚合物多孔载体制备及其三相流化床生物挂膜特性研究

针对目前流化床载体在生物挂膜过程中存在密度大、流态化能耗高、孔隙率低、亲水性及生物亲和性差、挂膜周期长等缺点,采用界面聚合发泡法制得亲水性聚合物多孔载体,通过接枝葡萄糖、掺杂粉末活性炭改善载体的亲水性及热稳定性能,研究了单体组成、催化剂、发泡剂用量与载体密度、孔隙率、吸水率的关系,并利用BET、FT-IR、TG分析表征了亲水性多孔载体孔结构及物化性能;并通过4种不同载体的生物流化床挂膜实验考察了载体表面特性对生物挂膜量、生物活性的影响,同时揭示亲水性聚合物多孔载体生物挂膜性能的机理.结果表明,制备体积1 L的亲水性多孔载体最佳组分为:聚醚三元醇用量50 g、TDI 20 g、葡萄糖7 g、粉末活性炭6 g、辛酸亚锡0.2 g、三亚乙基二胺0.4 g、发泡剂1.5g;所制备的载体具有表面亲水性及丰富的大、中孔结构,吸水率达到315.2%,孔隙率为91.7%;通过葡萄糖接枝、粉末活性炭掺杂增加了亲水性基团羟基及载体的吸附性能,附着的生物量达到4.65 gVSS/L、生物活性SOUR值为103 mgO2/(gVSS.h),均高于其它3种载体.证明亲水性多孔载体的高孔隙率、高亲水性及引入的强吸附剂均有助于载体表面微生物的生长,是一种适合于三相流化床反应器的载体.

Study on Synthesis of a Hydrophilic Porous Carrier and its Properties for Biofilm Formation in Three- phase Fluidized Bed Reactor

The current carriers for biofilm formation in three-phase fluidized bed reactor have some disadvantage such as high density,smooth surface and hydrophobicity etc.A new style hydrophilic porous (GPUC) carriers addition of glucose and absorbent-power activated carbon was prepared by foaming method.The effects of monomer composition,catalyses and foaming agent on the structure character of the GPUC carriers were studied.The structure of GPUC carriers was characterized by BET,IR spectra and thermal analysis (TG) and the mechanism was further explored.Four kinds of contrast test were made using the GPUC carriers,the neat porous carriers,granular activity carbon (GAC) and polypropylene particles for forming biofilm in three-phase fluidized bed reactor to study the effect of carrier surface physicochemical property on biofilm and bioactivity.The results showed that the optimized composition was made of polyether triol of 50 g,toluene diisocyanate of 20 g,glucose of 7 g, PAC of 6 g,stannous octanoate of 0.2 g,triethylene diamine of 0.4 g,water of 1.5 g.Under the conditions,the porosity and water absorption of GPUC carriers were 91.7% and 315.2%,respectively.The biomass and bioactivity attached on the GPUC carriers were 4.65 gVSS/L and 103 mg O2/(gVSS.h),respectively,which were higher than other three carriers.It concluded that high porosity,absorption ability and hydrophilic surface accelerated microorganism growth on the carriers.