Process Overview

A typical AnaeCo™ Plant based on AnaeCo’s proprietary technology platform will process waste in two key stages.

The Material Recovery stage takes less than 30 minutes. It ensures 75% or more of all incoming MSW is recycled. All operations are controlled using a proprietary process control system that maximises plant safety and efficiency. 

MSW is received and undergoes pre-sorting to remove oversized or hazardous materials before being loaded onto a feed-conveyor.

The feed conveyor transfers the waste into the AnaeCo™ Material Recovery Facility (MRF) where it undergoes a primary rapid mechanical separation process incorporating AnaeCo’s proprietary homogenising screening trommel. With the addition of water, the waste is homogenised and a series of screens rapidly separate the waste into fine organic, coarse and oversize fractions.

Coarse and oversize fractions are transferred via conveyor to additional processing lines where they are separated into recyclable ferrous metals, nonferrous metals and PET, HDPE and PVC plastics. They are then prepared for sale.

The fine organic fraction, representing around 95% of available incoming organic material, goes through a magnetic separation process to recover ferrous metals before undergoing AnaeCo’s proprietary two stage Wet Density Separation (WDS) process to remove glass, grit and other heavy inert materials. This removes up to 99% of contaminants from the organic stream with under 5% loss of organic material. Additional removal of light film plastics from the organic fraction can be achieved by forced draft, cyclone separation via combined agitation and wind sifting in an additional product refining process.

The dewatered clean organic stream is delivered to the DiCOM™ Bioconversion Facility (BCF). The process water is recycled through the primary mechanical sorting process and downstream biological processing with the entrained organics converted to biogas.

Depending on prevailing markets for outputs, the material recovery and product refining process can be configured to produced a Refuse Derived Fuel (RDF) for use as a supplement or replacement for fossil fuels used in industrial processes.

This hybrid biological process seamlessly integrates natural anaerobic and aerobic bioconversion processes in a single DiCOM™ vessel. The patented process creates a unique environment for the microbial population, resulting in accelerated bioconversion of organic material to produce stabilised quality organic fertiliser and biogas in a 21-day cycle. Depending on processing requirements, a series of DiCOM™ vessels provide continuous service through sequenced batch processing. Every step is managed by a control system for optimum energy efficiency and biological process stability.

The DiCOM™ Bioconversion process involves 3 phases:

Phase 1: Loading and aerobic processing – up to 5 days

The DiCOM™ vessel is fed by conveyor with the clean, homogenised recovered organic material. Material introduced to the vessel undergoes aerobic treatment with AnaeCo’s patented pressurised  aeration method. This overcomes channelling and preferential flow path formation and enables processing in vertical vessels. The objective is to elevate the temperature of the organic material to that suitable for the subsequent high temperature anaerobic digestion without sacrificing significant biochemical methane potential that can be exploited in the anaerobic phase. The loading rate is flexible and reflects local government waste collection schedules, operating requirements and throughput of material recovery equipment and processes.

Phase 2: Anaerobic processing – around 11 days

Once loading is completed, the anaerobic process phase is initiated in the same vessel with the addition of a liquid containing a carefully maintained anaerobic bacterial culture. The bacterial inoculum is recirculated and maintained in the thermophilic temperature range (55°C) for around 11 days. The high temperature anaerobic digestion phase ensures pasteurisation and strips volatility from the organic material, converting the highly putrescible material into methane in the form of biogas whilst minimising odour generation. At the conclusion of anaerobic processing, the bacterial liquid is drained from the vessel and transferred to a process water storage tank where it is carefully controlled for  reuse in a subsequent cycle.

Phase 3: Secondary aerobic processing – around 5 days

When the anaerobic treatment is complete, air is re-introduced into the vessel in a controlled sequence to initiate the final aerobic composting phase.Intensive pressurised aeration occurs for about 5 days, converting the digested organic material to an aerobically conditioned and stabilised quality organic fertiliser requiring no further treatment. A key element of this final aerobic conditioning phase is the conversion of anaerobically produced compounds to stable forms that are not offensively odorous. At the end of the 21-day cycle, the market ready organic fertiliser is discharged from the base of each vessel via a screw conveyor system. It undergoes a final post screening before being dispatched for distribution. Following unloading, the vessels undergo preparation for the next cycle.

Throughout the process, all ventilation air and gases are captured and directed through a biofilter odour management system for onsite treatment. Because the two aerobic phases are ultra air efficient, the volume of odorous air to be treated is kept to a bare minimum.

The biogas produced during the anaerobic phase is scrubbed of impurities and fed to gas-fired generators for combined electricity generation and process heat capture. The continuous renewable energy produced during the process self sustains the system with a surplus available for export or storage.

Plant operations are managed through a proprietary process control system that ensures safe, compliant and efficient operations. The system monitors and adjusts DiCOM™ vessel conditions (moisture, temperature, pressure, oxygen, methane, carbon dioxide, pH) and regulates the flow of air and water to deliver optimal results and ensure process stability. An AnaeCo™ Plant includes ancillary systems and infrastructure to meet specific operating requirements.