DEVELOPMENT OF NEW ROTATING BIOLOGICAL CONTACTOR WITH SURFACE PROTRUSIONS AND SOLID-LIQUID SEPARATION

提出了一种新型的盘状介质，即具有表面突起的网状介质，以促进可溶性基质向附着在旋转生物接触器(RBC)上的生物膜的外扩散，突起高度为5 mm。在2rpm有8个突起的扩散层厚度约为100m，而没有突起的扩散层厚度约为200m。为了减轻滤盘的重量，采用了一种网状介质，发现在这种类型的介质上生物膜很发达，固体和网状介质中的氨通量几乎相同。在传统的RBC系统中，最终的澄清器已经用于分离处理后的废水和分离的生物质。分离的生物质在输送到最终澄清器的过程中暴露在槽内的湍流剪切中。这样的暴露将分离的生物质分解成更小的颗粒，这些颗粒不能在澄清器中沉淀。因此，据报道，RBC系统的出水中含有大量提供额外BOD的微小有机颗粒。在本研究中，建造了一个两层的RBC，以实现对槽中分离的生物量的同时去除。其上部和下部分别作为沉淀物的红细胞和储藏空间。这座两层楼的RBC是在一个四级单元中运行的。实验研究表明，两层RBC对剩余生物量的去除效率很高，出水悬浮物浓度可达10ppm左右。这意味着在两层楼的RBC中可能不需要最后的澄清器

A new disk media,i.e.,reticulated media with the surface protrusions,has been proposed to promote the external diffusion of soluble substrates to the biofilm attached to the Rotating Biological contactor(RBC).The height of protrusions was 5 mm. The diffusion layer thickness with 8 protrusions at 2 rpm was about 100 m,while it was about 200 m without protrusion. In order to reduce the disk weight,a reticulated media was used and it was found that the biofilm was well developed on this type of media, and ammonia fluxes were the almost the same in the solid and reticulated media.In a conventional RBC system,the final clarifier has been used to separate the treated waste-water and detached biomass. The detached biomass is exposed to the turbulent shear in the trough during the transport process to the final clarifier. Such an exposure breaks down the detached biomass into smaller particles which can not settle in the clarifier. As a result,it has been reported that the effluent from the RBC system containes a lot of small organic particles which offer the additional BOD. in this research,a two-story RBC was constructed to achieve the simul-taneous removal of the detached biomass in the trough. Its upper part and lower part function as the RBC and storage space of the settled biomass,respectively. The two-story RBC was operated in a four-staged unit. Experimental investigation showed that the removal efficiency of detavhed biomass in the two-story RBC was very hig to result in the effluent suspended solid concentra-tion of about 10 ppm. It means that the final clarifier may not be necessary in the two-story RBC