Wastewater treatment for bitumen extraction in Venezuela
By Andrew Hutton, Napier-Reid Ltd.
Two facilities for the extraction
of natural bitumen located in
the Jose Oil and Petrochemical
complex, north of
Anzoagetui State in the Orinoco delta
region of Venezuela will share a
wastewater treatment plant designed
and supplied by Napier-Reid of
Markham, Ontario.
Natural bitumen is extracted and
converted by a proprietary process into
an industrial fuel similar to bunker fuel
used in power generation plants. The
fuel production process is a license of
Intevep, the research and development
subsidiary of Petroleos de Venezuela
S.A. (PDEVESA).
The wastewaters are composed of
oily wastewater, hydrocarbons, proprietary
and contaminated rainwater from
10 different streams.
The process train consists of flow
balancing, pH control, chemical conditioning
with coagulants, flocculants,
Dissolved Air Flotation, biological
treatment using Sequencing Batch
Reactors with a Belt Filter Press for
surplus sludge dewatering. The final
effluent is discharged to the ocean. PH
control is required as the off-specification
tanks can spike at 12.0.
The Venezuelan government mandates
effluent standards covering
marine discharges.
The plant is fully automated and
controlled by PLC. The Dissolved Air
Flotation Cell is located in a hazardous
area requiring all equipment in this
area to be explosion-proof. The biological
plant is in a non-hazardous area.
All process equipment was subject to
rigorous adherence to specification
and independent inspection.
Table 1 — plant design criteria.
Napier-Reid was selected in an
invited tender process in conjunction
with its Colombian engineering representative.
Napier-Reid is responsible
for the overall process design, equipment
selection, supply, start-up and
operator training. Construction is
underway and the plant is due to start
operating this summer.
