The La Farfana sewage treatment works is the biggest in Chile and one of the largest in the world. It serves a population of 3.7 million people, and treats around 60% of wastewater from the capital Santiago.
Halcrow was commissioned to develop both short- and long-term, sustainable solutions to odour and sludge disposal at La Farfana that will improve the quality of people’s lives in the city.
The first thing we did was to carry out an audit of the existing sludge treatment facilities and odour, after which the team looked at the design and operation of the works. The sewage treatment process employs state of the art activated sludge, anaerobic digestion and centrifuge dewatering.
The Halcrow team also carried out an independent environmental analysis of potential sludge disposal routes and treatment opportunities to find the best practical solution. During this analysis we looked at the experiences of water companies around the world, and considered the environmental, financial and technical merits of all the latest treatment and disposal options, as well as their sustainability. Potential sludge treatment options identified during the project included thermal drying and composting.
The La Farfana project required an integrated, interdisciplinary approach that involved Halcrow’s process, civil, mechanical, financial specialists, while local engineers provided knowledge of Chilean law and approved codes of practice.
After completing the sludge management plan Halcrow was appointed to design a platform to stabilise, store and recycle the sludge.