Waste Water Treatment Plant for Marini Asphalt Plant
Client: Lagos State Public Works Corporation, Isheri
Background:
Lagos State Public Works Corporation is an agency of the Government of Lagos State, Nigeria established to undertake construction and maintenance of roads in the State by direct labour.
As part of its various facilities, the agency owns and operates an Asphalt plant at its Isheri Yard. This plant utilizes Bitumen, sand and other aggregates in a high-temperature kiln to produce the Asphalt.
The flue gases emanating from the plant contain a lot of particulates, and constitute a menace to the immediate neighbouring communities of Omole Phases I & II, Isheri, Olowora and Magodo.
To control this, the plant came equipped with a wet scrubber (dust collector) to remove particulate matter from the effluent gas stream. The removal process is by extracting the particles by water sprayed directly into the dust collector. However, the water usage is high and the disposal of the particulate-laden waste water has become a major challenge.
LSPWC’s Requirements
LSPWC therefore requires the installation of effluent water purification and recycling facility to conserve water by reducing the quantity of water drawn from the aquifer and discharged to waste, reduce pollution by preventing discharge of unpurified effluent water to waste, and ensure that dust collected as sludge is properly disposed off or recycled as aggregates for Asphalt production.
Facilities Provided
KEMENG has designed, constructed and installed a waste water treatment plant consisting of a 3-chamber sedimentation tank, a filter vessel for polishing recycled water and a sludge drying bed to dry and collect the removed particulates.
KEMENG has also installed an adequately–sized pump to recycle the conserved water back to a holding tank as well as requisite pipe installation to effect same.
Key Benefits
LSPWC Asphalt plant is now able to scrub the effluent gas stream, effectively reducing the particulate load in the flue gases.
The installation has substantially mitigated the negative impact of the LSPWC Asphalt Plant on the immediate neighbourhoods of Omole, Isheri and Olowora.
In addition, the particulates so removed are now being recycled for compacting into paving stones (briquettes) for road rehabilitation.
Project Information:
Contract Value: N10,982,785.
Start Date: November 2011
Completion Date: January 2012
Project Financing: Lagos State Government Appropriation 2011
LSPWC Asphalt Plant Internally Generated Revenue