一种包埋微生物复合填料的制备及性能评价

Preparation and performance evaluation of a composite filler embedding microorganisms

采用包埋法制备出一种复合生物填料,测其各项理化性质,并以NO x模拟废气验证其脱硝性能。填料主要由碳酸钙、牛粪堆肥腐殖质、菌剂载体、水泥、轻质珍珠岩、立体网状纤维及脱硝功能微生物等复合而成,粒径12 mm×20mm,自然堆积密度(471±0.8)kg/m3,持水量(49±1.3)%,比表面积3.91 m2/g,平均机械强度(427.3±0.2)N,pH为10.5±0.2。填料能长期在潮湿环境中保持良好的粘结强度,并具有营养缓释及pH缓冲能力。包埋脱硝功能微生物复合填料中初期微生物数量5.3×105CFU/g,运行60 d后微生物数量达到8.6×108CFU/g,闲置停运30 d微生物有所减少,但重启后净化效率基本不变。当进气负荷低于1 878 mg/(m3·h),气体停留时间为14.47 s时,BF1的去除率高达93.15%。

A novel biological filler was prepared by embedding method. The physicochemical properties and performances in a pilot-scale biofilter on treating NOx waste gas were investigated. The filler was composited with CaCO3 ,compost humus,carrier for microorganisms,light pearlite,cement and reticular fibre. The composite granule prepared was a porous granule （Φ12 mm×20 mm） with a bulk density of （471 ±0.8）kg/m3 ,a moisture retention capacity of （49 ± 1.3）% , a specific surface area of 3.91 m2/g, an average strength of （427.3 ± 0.2）N,and pH of 10.5 ± 0.2. The filler could retain well bonding strength in high humidity environment for a long time and provide nutrients for the growth of microorganisms,in addition,it could prevent the large fluctuate of pH. At the beginning of the experiment,the quantity of microorganism was 5.3 × 10 5CFU/g. After 60 days,the quantity increased to × 10 5CFU/g. The microorganism decreased slightly after 30 days＇ lay-up period,while the purification efficien- cy almost stayed at the same level after restarting. The removal efficiency of NOx remained over 93.15% when the intake loading of BF1 was less than 1 878 g/（m3· h） and EBRT was 14.47 s.