More than 15,000 tons of sewage sludge per year: HUBER installs solar sewage sludge drying technology on Pachacútec WWTP (Peru)

HUBER supplies the technology for solar sewage sludge drying for the wastewater treatment plant in Pachacútec. The plant, located more than 10,000 kilometres from HUBER’s Berching site, is already the second project in Peru using the innovative drying technology with the HUBER Sludge Turner SOLSTICE® and solar energy.

The solar sludge drying with HUBER Sludge Turner SOLSTICE® beeing installed
The solar sludge drying with HUBER Sludge Turner SOLSTICE® beeing installed
The construction work is in full swing
The construction work is in full swing

Among others, three HUBER Sludge Turner SOLSTICE®: HUBER supplies innovative components for sustainable sewage sludge drying using solar energy

HUBER supplies three HUBER Sludge Turner SOLSTICE® 11 units and the conveying system consisting of two HUBER Screw Conveyors Ro8 T 355 with a total length of about 70 metres. In addition, HUBER supplies the control elements and takes care of delivery and erection of the glasshouse with a total area of more than 5,200 square metres.

The project in Pachacútec, approximately 30 kilometers north of the city center of the Peruvian capital Lima, is about three times larger than HUBER’s first installation in Peru, the existing solar drying plant in Arequipa in the south of the Andean country. According to the overall responsible water division Agua of the Spanish construction company Acciona, the Pachacútec wastewater treatment plant will treat the wastewater of about 200,000 people in the future. The contract value for HUBER amounts to about 1.6 million euros.

“The successful implementation of such projects requires detailed project planning and the joint commitment of all parties involved,” says Marcin Stańczak, project manager at HUBER. “But this is worth it – especially in the execution phase on site, because the customer gets a reliable and efficient plant.”

For agricultural use: over 15,000 tonnes of sewage sludge and 13.5 million cubic metres of water per year

The Pachacútec treatment plant treats, among others, municipal sewage sludge, which is dried in the 145-metre-long and 12-metre-wide glass house by HUBER Sludge Turner SOLSTICE® units using solar energy. The plant has a daily water capacity of about 37,000 cubic metres, which corresponds to about 13.5 million cubic metres per year. More than 15,000 tonnes of wet sewage sludge will be dried from an initial 20 percent to up to 85 percent dry residue. Thus, almost 12,000 tonnes of water evaporate per year. The dried and granulated sewage sludge is then used, for example, in agriculture as a soil fertiliser and cultivating agent.

Construction site with the greenhouses for the solar sludge drying
Construction site with the greenhouses for the solar sludge drying
Construction site with the greenhouses for the solar sludge drying

Turnkey project for HUBER: the challenges in project management

The project is a turnkey project for HUBER: the Berching-based company acts as the appointed general contractor for the entire solar sewage sludge drying process and coordinates the local resources from faraway Berching to present a turnkey solution.

„Our team on the site consists of about 25 people. Besides the distance of more than 10,000 kilometres and the time difference, the Covid pandemic of course continues to present us with challenges,” says Marcin Stańczak. “We are installing state-of-the-art products and control elements and working with a new supplier to build the glasshouse. So far, thanks also to the excellent support of our Chilean subsidiary HUBER Latin America, we are mastering all challenges and the assembly work is progressing.”

Annual global radiation of over 2,000 kilowatt hours per square metre: Pachacútec offers excellent conditions for the use of solar energy

The Pachacútec site offers excellent conditions for HUBER’s innovative technology using solar energy: the annual global radiation here is over 2,000 kilowatt hours per square metre. According to the official definition of the German Weather Service, global radiation is the solar radiation received on the ground from a horizontal plane. For comparison: in Germany, the annual global radiation averages about 1,000 kWh/m² and is thus half as high as in Pachacútec. In sunny Spain, the radiation is a good 1,650 kWh/m² annually, and in Brazil and India, for example, the values are similar to those in Pachacútec.

Project consists of two parts: start in 2019 and important progress in 2020/2021

The project, which started in 2019, consists of two parts: firstly, the construction of the Pachacútec wastewater treatment plant itself, and secondly, the construction of the outfall for the discharge of the treated wastewater into the Pacific Ocean, for which a land outlet and an underwater outlet will be used.

In 2020, several advances were already made in the realisation of the project, for example the construction of the aeration basins, the sludge thickeners and the disinfection chamber. In 2021, work continued on the clarifiers and the sludge return pump chamber, as well as the earthworks for the solar drying technology, which is part of the sludge treatment system.

Acciona Agua, the water division of the construction company Acciona, is responsible for overall project: wastewater treatment plant part of a multi-phase expansion plan

The construction of the wastewater treatment plant is part of the third stage of the “Plan for the Expansion and Improvement of the Drinking Water and Sewer for the Pachacútec Macro Project” (Plan de Ampliación y Mejoramiento del Sistema de Agua Potable y Alcantarillado para el Macroproyecto Pachacútec). Responsible for the realization of the overall project is Acciona Agua, the water division of Acciona, a Spanish company active in building construction, civil engineering and infrastructure.