Water & Wastewater Asia March/April 2024

IN THE FIELD
Pork producer
cuts emissions
with on-site
sludge treatment
By Joanne Allen, head of business development,
WCS Environmental Engineering (WCSEE)
management company. This was
costing the site time and money,
carrying a high carbon footprint.
The Pilgrim’s UK engineering
team wanted to investigate the
possibility of adding an extra
stage to the wastewater treatment
process to dewater the sludge
onsite. This would reduce the cost
of transportation and associated
carbon emissions. The team
also wanted to find a use for the
dewatered sludge, to help realise
Pilgrim’s UK circular economy
ambitions in designing waste out of
the pork production process. Site
services manager at Pilgrim’s UK
Andrew Hill said, “Pilgrim’s UK has
ambitions to reduce on-site waste
through design and implementation
of circular economy processes.
The engineering team wanted
to investigate the possibility of
dewatering onsite, to reduce the
cost of transportation and carbon
emissions, and to see whether the
dewatered sludge had value.”
TEST AND ANALYSIS
Pilgrim’s UK approached the
engineering team at WCSEE to
carry out a free laboratory test and
analysis to find out more about
the composition of the sludge and
1
1 Pilgrim’s UK
Spalding plant
2 A volute screw
press installation
3 Another volute
screw press
installation
When Britain’s biggest provider
of higher welfare pork wanted to
reduce processing plant sludge
transport costs, WCSEE was
not only able to reduce carbon
emissions, but also drive green
energy generation. Pilgrim’s UK is
ambitious about energy and carbon
emissions reduction targets and
has pledged to become net zero
by 2030. It has already reduced its
company-wide direct and indirect
carbon emissions by 62.5% since
2019 and its indirect emissions in
the supply chain by 9%.
Pilgrim’s UK pork processing plant
in Spalding, Lincolnshire, UK, saw
an opportunity to reduce sludge
tankering journeys to and from
the facility. The company already
treats its own wastewater which is
processed through a dissolved air
floatation (DAF) treatment system
to meet high environmental trade
effluent consents. A byproduct of
the DAF process is liquid sludge,
which was historically collected from
the plant and transported offsite
up to six times a week for further
processing by the sites waste
understand treatment options.
The technical team at WCSEE then
designed and developed optimal
chemical and mechanical treatment
options to economically process the
sludge at the Pilgrim’s UK Spalding
plant. This involved a trial installation
of the screw press for five days to
demonstrate its dewatering and
sludge thickening capability.
The screw press model supplied
was specified to meet the volumes
of sludge the site was producing
along with the correct blend of
chemicals and precise dosing
measurements. The plant was
also assessed to identify the best
26 Water & Wastewater Asia | March-April 2024