5Yu H Q, Tay J H,Fang H P. The roles of calcium in sludge granula-tion during UASB reactor start-up [ J ]. Water Research, 2001, 35(4) : 1052.
6Yu-Chuan Juang, Sunil S Adav, Duu-Jong Lee, et al. Stable aero-bic granuls for continuous flow reactors : precipitating calcium and i-ron salts in granular interiors [ J ]. Bioresource Technology, 2010,101(6) : 8051.
7Angela Manas, Mathieu Pocquat, Beatrice Biscans, et al. Parame-ters influencing calcium phosphate precipitation in granule sludge se-quencing batch reactor[ J]. Chemical Engineering Science, 2012,77(2) : 165.
8Langrank E A Van, Gill G G, Aelst A Van,et al. Effects of highcalcium concentrations on the development of methanogenic sludge inupflow anaerobic sludge bed( UASB) reactors[ J]. Water Research,1998,32(4) : 1255.
9Ghangrekar M M,Asolekar S R,Joshi S G. Characteristics of sludgedeveloped under different loading conditions during UASB reactorstart-up and granulation [ J ]. Water Research, 2005, 39(2); 1123.
10Pevere A, Guibaud G, Van Hullebusch ED, et al. Effect of Na +and Ca2 + on the aggregation properties of sieved anaerobic granularsludge[ J]. Colloids and Surfaces A; Physicochem. Eng. Aspects,2007,306(2) : 142.