ANAJO

The initial situation

Jordan is one of the most water-scarce countries in the world. As freshwater resources are limited, municipal wastewater is highly concentrated with organic pollutants. This is reflected in its chemical oxygen demand (COD), which averages between 760 and 1,500 mg/L. COD indicates the amount of oxygen required to chemically oxidise the substances present in wastewater.

Conventional wastewater treatment plants consume large amounts of energy to supply oxygen to the wastewater. Aeration alone accounts for 50–70% of their total energy consumption. In addition, the disposal of sewage sludge generated during wastewater treatment is costly and can pose environmental risks.

The approach

The project tested anaerobic pre-treatment, a process in which microorganisms break down organic matter in wastewater without oxygen. This reduces energy demand and produces biogas that can be used as an energy source. It also reduces the amount of sewage sludge generated.

The technology was based on the Upflow Anaerobic Sludge Blanket (UASB) process. In this process, wastewater flows upwards through a sludge blanket containing microorganisms that break down organic matter. The project combined this process with a downstream biological treatment stage (the AS system) to improve the overall treatment performance.

The project team designed and built a transportable pilot plant in Germany, housed in a 20-foot container. The plant was then tested at the Abu-Nusier wastewater treatment plant in Amman. During an initial six-month start-up phase, the microorganisms were allowed to adapt to the operating conditions. The team subsequently tested the plant in three operational phases, varying the organic loading and accounting for seasonal temperature fluctuations.

The objectives and measures

The project aimed to determine whether the technology could operate reliably and cost-effectively under Jordan's climatic conditions. The team assessed the plant's wastewater treatment performance, biogas production and ability to reduce the amount of sewage sludge generated.

A feasibility study also examined whether the process could be implemented at an existing wastewater treatment plant in Jordan and what savings could be achieved through full-scale application.

The results

The pilot operation demonstrated that anaerobic pre-treatment works reliably under Jordan's climatic conditions. The plant effectively removed organic pollutants from the wastewater, generated usable biogas and significantly reduced the amount of sludge produced.

The feasibility study indicated that implementing the process at an existing Jordanian wastewater treatment plant could substantially reduce energy consumption and sludge disposal costs. The technology therefore offers a way to make wastewater treatment in Jordan more resource-efficient.

The project also strengthened knowledge transfer to the Jordan University. Handing over the fully operational pilot plant provides a lasting basis for further research and development, as well as for the wider adoption of the technology across the region.

The project contributes to three United Nations Sustainable Development Goals (SDGs): SDG 6.3 (improving water quality and wastewater treatment), SDG 7.a (international cooperation in the field of sustainable energy) and SDG 6.a (international cooperation in the water and sanitation sector).