| 摘要 |
#CMT# #/CMT# An effluent creening device has a set (E) of connected hollow fiber membranes (M) in compact module(s) (4), to be immersed in an effluent channel (2) with the fibers transverse to the effluent stream flow direction. The effluent passes around the membrane walls without crossing the walls. Fibrous waste is trapped on the fiber exterior surface, and the interior volume of the fiber is free of suction. #CMT# : #/CMT# Independent claims are included for: (1) a method for using the effluent screening device, including a stage of cleaning membranes used for screening by chemical and especially enzymatic methods; and (2) an effluent treatment plant having a membrane bioreactor, which includes a screening device as above upstream of the bioreactor. #CMT#USE : #/CMT# The screening device is placed in the inlet channel of an effluent treatment plant (specifically a membrane treatment plant) to retain fibrous waste before the treatment plant, the effluent specifically being residual municipal and/or industrial effluent (all claimed). Typically non-biodegradable or slowly biodegradable fibers (such as hair, fur or cellulosic residues) are removed from waste water, to prevent blocking of channels, pumps, stirrers etc. and to eliminate various maintenance problems. #CMT#ADVANTAGE : #/CMT# Fibrous waste is removed selectively at relatively low cost. A used, degraded liquid filtration membrane can be utilized as the fiber removing membrane. With cleaning, the device has a long operating life. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The figure shows a schematic vertical section through an effluent screening device, with the set of hollow fiber membranes aligned vertically. 1 : Screening device 2 : Inlet channel 3 : Effluent to be treated 4 : Compact module 5, 6 : Molded holding blocks for ends of membranes 7 : Collector B : Fibrous waste E : Set of connected membranes H : Difference in height of effluent levels L1, L2 : Effluent levels upstream and downstream of membranes M : Membranes Z1 : Vertical size of set of membranes #CMT#ENVIRONMENT : #/CMT# Preferred Apparatus: The set (E) of connected hollow fiber membranes has previously been used for filtration of liquid thrugh the membrane wall, in which the integrity and/or permeability has deteriorated sufficiently to prevent effective filtration, specifically having a permeability less than half of that of a new membrane. The set of membranes is immersed in the effluent channel with the fiber direction perpendicular to the effluent flow direction, and vertical or horizontal. The hollow fiber membranes are of mineral and/or organic material, especially of a hydrophobic polymer-hydrophilic polymer alloy. The hollow fibers have external diameter 0.1-3.0 mm and internal diameter 0.05-3.0 mm. |
