In April 2006 Petrochemical company Chevron, previously Caltex, and Improchem opened a R30-million joint venture project at the Chevron Refinery that seeks to save water for the Western Cape province.
The water recycling plant (owned and operated by Improchem) draws treated sewage water from the Potsdam Wastewater Works (that normally gets dumped into the sea) in Milnerton and upgrades it for industrial use at the Chevron refinery.
The sewerage water is purified to near drinking quality using clarification, ultra-filtration and reverse osmosis technology, and is then supplied to the refinery for use as steam, cooling water and firewater. The purification process is essentially a two stage process. The first stage involves the separation and removal of suspended solids and other compounds from the sewerage water through air flotation and ultra-filtration. In the second stage, the inorganic dissolved solids or salts are removed in the reverse osmosis units. The final product is similar in chemistry to the water presently supplied by the City of Cape Town.
Prior to this project the refinery used about 5,7-million litres of water per day, which is the average daily water consumption of about 38 000 people.
The project also has an environmental benefit as it minimises the amount of treated effluent water discharged by Potsdam to sea via the ecologically sensitive Milnerton lagoon.
Construction of the water recycling plant began in March 2005. Over 100 people were employed during the nine-month construction period and only local Cape Town contractors were used. The new plant provides permanent employment for five people.
The new plant was successfully commissioned on February 2, 2006.
Some of the existing users of the treated effluent from the Potsdam scheme include the Milnerton Golf Course, four schools in Milnerton and Table View, the Chevron refinery, Table View beachfront dunes, Theo Marais Park and agricultural users (including wine farmers in the Durbanville region).
28 June 2006