Sludge Watch ==> Victoria BC - Treatment Ideas to be Graded - read report

[Maureen Reilly]

Treatment ideas to be graded
Rob Shaw, Times Colonist
Victoria, British Columbia
Canada
Thursday, February 15, 2007


Engineers have drafted a sewage treatment report card that gives potential 
technologies a pass or fail grade on if they'll work in Greater Victoria.

Emerging technologies such as turning sewage waste into plastic, or 
processing it into hydrogen or fuel cell energy, have not been proven to be 
of use to the Capital Regional District, according to a consultant's report 
prepared by CH2M Hill and Associated Engineering.

"If it's not a proven technology, it's something we'd be careful with," said 
Dwayne Kalynchuk, CRD general manger of Environmental Services.

The ideas that are considered feasible are: Using membrane treatment 
followed by wetlands; extracting useable water from sewage; creating 
biosolid sludge that could be processed into fertilizer; using thermal 
incineration; producing cement from sewage; and extracting heat and power 
from digester gas.

Some particularly interesting ideas are using bioreactors at Hartland 
Landfill to collect gas from sludge left over after treatment, said 
Kalynchuk. As well, the consultant's report says it may be feasible to melt 
biosolid sewage waste into bits of glass to be used in concrete, he said.

The consultant's report also lists types of appropriate secondary treatment 
and ultra-violet disinfection.

But an issue of particular concern for Greater Victoria will be how 
treatment plants handle all the rain that spills into the storm sewer system 
and mixes with sewage before flowing into treatment plants.

Rain can increase the sewer flow between five to eight times normal levels, 
but it's not always necessary to treat rainwater, said Kalynchuk.

How much rainy sewage could be treated at a high level would depend on if 
the CRD choose multiple smaller plants, or one or two large centralized 
plants.

To read the entire consultant's report and view charts, click on

Discussion Paper #3 on the CRD website at

www.crd.bc.ca.

////////////////////////////////////////

http://www.canada.com/victoriatimescolonist/news/story.html?id=c680090c-62de-4ba4-8bfa-97202a0d7f42&k=34520