| The AFDMBR and AFMBR are used to treat urban sewage in order to achieve the standard discharge of domestic sewage.An DMBR was run to choose the optimal operation parameter and application than AFDMBR,searched the optimal operation parameters of AFDMBR and AFMBR,inspected and membrane pollution,and carries on the comparison to two types of reactor.AnDMBR test experiment results showed that the optimal membrane module aperture for 300 stainless steel net,the sludge concentration of 2000 mg/L,flux was32 L/(m~2·h)carried out under the condition of continuous experiments showed that AnDMBR and stable operation cycle is 240 h.The cleaning experiment results showed that the off-line cleaning method is more suitable for the removal of dynamic film.Sparging had effect on AFDMBR,The sparging intensity was too large to cause the dynamic film to be damaged,and was too small to control the membrane fouling,the optimal aeration strength of this experiment was 30 m~3/(m~2·h),intermittent sparging(the suction stop ratio is 7:1)could effectively slow the membrane fouling.During the membrane fouling period,the average amount of effluent COD was 100mg/L,the removal rate of COD was 87%,and the interception rate of the dynamic membrane was up to 22.75%,the concentration of SMP in sludge mixture was highest,it was 33.71 mgTOC/L.AFMBR runs 120 d and its critical sparging strength was 35 m~3/(m~2·h).During operation,the concentration range of COD was 429.5~648.1 mg/L,and the removal rate of COD was 71.72~91.66%.The cleaning of membrane could effectively remove the membrane surface contaminants by using the off-line chemical cleaning method.SMP had a relatively large influence on membrane fouling,with the highest concentration of SMP on the membrane surface,it was 27.84 mgTOC/L,and the highest polysaccharide content in SMP components,it was 14.59 mgTOC/L.AFDMBR had the advantages of high throughput,low cost,low energy consumption,easy cleaning,etc.But its operation was not stable,and the short running cycle needed to be solved further. |
