TY - JOUR
T1 - Grey water treatment in stacked multi-layer reactors with passive aeration and particle trapping
AU - Prajapati, B.
AU - Jensen, M. B.
AU - Jørgensen, N. O.G.
AU - Petersen, N. B.
PY - 2019/9/15
Y1 - 2019/9/15
N2 - When adequately treated, grey water represents a potent alternative water resource, as it constitutes a large proportion of household wastewater. The objective of this paper was to test a full scale version of a novel compact grey water treatment technology, based on passive aeration and particle trapping in multiple layers. Using a modified dual porosity filtration technology, grey water from a public bath was passed through a stack of eight reactors, each 0.75 m × 0.55 × 0.22 m, serially connected for gravity driven flow from top to bottom in a zig-zag pattern. The topmost reactor served as pre-filter for removal of hair and other larger debris. The lower seven reactors facilitated degradation of bulk organic contaminants in biofilm established on a stack of five fibrous polyamide nets, and trapping of particles by sedimentation on five interlaid corrugated plastic plates. By operating the reactors in a time-controlled batch-mode, the corrugated plates further served to trap air and thus ensure passive aeration of the subsequent batch. The production rate was 1.2 m3/d and the hydraulic retention time 2 h, at an aerial footprint of 0.4 m2, excluding storage tanks. After two weeks of initialization, a biofilm had established and the system was monitored for additionally three weeks. Significantly improved effluent quality was obtained as measured from reductions in turbidity (95%), total suspended solids (94%), chemical oxygen demand (87%), and microbiological parameters (55–98%), and from stable level of dissolved oxygen in effluent of 3.5 mg/L. Future optimization includes custom-made reactors for maximizing production capacity, improved removal of total N and total P, and addition of final disinfection.
AB - When adequately treated, grey water represents a potent alternative water resource, as it constitutes a large proportion of household wastewater. The objective of this paper was to test a full scale version of a novel compact grey water treatment technology, based on passive aeration and particle trapping in multiple layers. Using a modified dual porosity filtration technology, grey water from a public bath was passed through a stack of eight reactors, each 0.75 m × 0.55 × 0.22 m, serially connected for gravity driven flow from top to bottom in a zig-zag pattern. The topmost reactor served as pre-filter for removal of hair and other larger debris. The lower seven reactors facilitated degradation of bulk organic contaminants in biofilm established on a stack of five fibrous polyamide nets, and trapping of particles by sedimentation on five interlaid corrugated plastic plates. By operating the reactors in a time-controlled batch-mode, the corrugated plates further served to trap air and thus ensure passive aeration of the subsequent batch. The production rate was 1.2 m3/d and the hydraulic retention time 2 h, at an aerial footprint of 0.4 m2, excluding storage tanks. After two weeks of initialization, a biofilm had established and the system was monitored for additionally three weeks. Significantly improved effluent quality was obtained as measured from reductions in turbidity (95%), total suspended solids (94%), chemical oxygen demand (87%), and microbiological parameters (55–98%), and from stable level of dissolved oxygen in effluent of 3.5 mg/L. Future optimization includes custom-made reactors for maximizing production capacity, improved removal of total N and total P, and addition of final disinfection.
KW - Decentralized
KW - Dual porosity filtration
KW - Grey water reuse
KW - Low-cost
KW - Multi-layer reactor
KW - Space-efficient
UR - http://www.scopus.com/inward/record.url?scp=85066963292&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2019.05.096
DO - 10.1016/j.watres.2019.05.096
M3 - Journal article
C2 - 31195334
AN - SCOPUS:85066963292
SN - 0043-1354
VL - 161
SP - 181
EP - 190
JO - Water Research
JF - Water Research
ER -
