Annual report 2006-2007 - Taranaki Regional Council

10
Waste liquor and floor washings from the rendering process are pumped up to the
drainage system. Boiler condensate is disposed of in a soak hole.
The Company disposes of material unsuitable for rendering by composting in a
paddock next to the effluent treatment system. The composted material is then
spread over pasture.
Several notable improvements have been implemented for processing operations at
Taranaki Abattoirs. These include separation of blood from the waste stream that
feeds the anaerobic pond, the diversion of stormwater and run-off from the
stockyard roof from the effluent treatment system, processing modifications to
increase tallow recovery, and recycling of water.
In the 2001-2002 monitoring period a further set of fat traps were added to the
wastewater system. These were constructed alongside the milliscreen, and the flow
from the abattoir and the rendering plant is directed through them. This
improvement has the advantage of separating out more of the fat that was
previously sent to the pond system, thereby reducing the frequency at which the
Company exercises its consent [5221] for discharging excess waste from number one
pond onto and into land in the vicinity of an unnamed tributary of the Kahouri
Stream.
Also in the 2001-2002 monitoring period as a result of an unauthorised discharge of
untreated wastes to the unnamed tributary of the Kahouri Stream due to a blockage
in the manhole at the anaerobic pond inlet, an open drain has been dug between the
manhole and the anaerobic pond. If a blockage occurs that is not observed at the
daily inspection of the treatment ponds, any overflow at this manhole will be
directed to the pond.
A new condenser which was put in place in May 2004 has ensured that temperatures
of the gas flow to the biofilter are kept to levels which enable the efficient operation
of the biofilter and reduce odours from the plant. This was further enhanced by the
addition of a ‘cooling drum’ in the 2005-2006 monitoring year.