Accel-o-Fac® Wastewater Treatment System
Zero-to-Low Energy 100% Total On-Site Treatment
Accel-o-Fac® is a zero-to-low energy wastewater treatment system requiring no sludge handling and utilising wind energy. In many cases, there is little in the way of ongoing operating costs.
Accel-o-Fac® is a long-term sustainable “All-in-One” wastewater treatment system. Based on the tried and proven facultative biological process, Accel-o-Fac® (accelerated facultative™) has successfully treated a wide variety of wastewater for decades. Accel-o-Fac® provides Water Companies and other entities with extremely robust, odour free wastewater treatment that requires little in the way of operator attention or maintenance and, best of all, no sludge handling or removal — truly “All-in-One” 100% total treatment on site.
These benefits are accomplished with almost zero operating cost by employing wind power as the primary energy source and through the use of highly specialised equipment combined with a number of unique design, construction and operation techniques. The net result is a total “optimisation” of a purely biological process resulting in an overall acceleration of the processing rate. This “optimisation” enables Accel-o-Fac® wastewater treatment plants to be smaller than old-fashioned WSP designs — all at zero-to-low operating cost and without the use of expensive and complex conventional mechanical aeration, chemicals or significant manpower.
Enhancing the Facultative Biological Process
Accel-o-Fac® not only boosts natural oxygen transfer, but also provides an ideal quiescent zone for solids settling and self-digestion of the sludge — a fundamental and essential part of the “All-in-One” facultative biological 100% total treatment process.
The Accel-o-Fac® system also eliminates the problems of short circuiting by radially dispersing and distributing the incoming organic load throughout the entire treatment volume. With Accel-o-Fac®, the entire cell volume and surface area are put to work with no dead spots and no “hot” or overloaded spots (such as near the influent area). This alone dramatically increases the processing capacity of the cells enabling it to automatically deal with shock loads.
Accel-o-Fac® can accommodate huge variations in flows without any operating problems. Storm water flows, peak flows, seasonal increases are all effortlessly handled.
Self Digesting Sludge
Long term studies prove these systems anaerobically self-digest all organics within the system with the inert materials accommodated for the life of the plant. That can be an important consideration with regulations and concerns regarding sludge disposal and handling. Accel-o-Fac® acheives this important benefit by ensuring correct loadings and detention times as part of the overall design process along with optimised conditions within the system.
New Construction or Retrofit
Accel-o-Fac® can be designed as a new wwtp such as was done for the Holkham Estate and Village. On the other hand, the Accel-o-Fac® system can be retrofit to existing lagoons where it can solve serious issues, boost performance and in many cases, replace existing expensive aeration.
Australian Retrofits
As an example, South Gippsland Water in Australia partially upgraded their Inverloch wwtp with the Accel-o-Fac system in April of 2014. Through routine monitoring of the conditions of the cell since installation, the utility company reported that not only had they benefited from a 16% increase in average DO, but they have also been able to significantly reduce the operation of the existing electric powered aeration system at the plant. This has provided South Gippsland Water with a 22% reduction in overall energy costs, which will pay for the upgrade within a few years of operation.
South Gippsland Water upgraded the Toora wwtp with the Accel-o-Fac system in April of 2015. Through routine monitoring of the conditions of the cell since installation, the utility company reported that not only have they benefited from a dramatic increase in average DO, but they have also been able to significantly reduce the operation of the existing electric powered aeration system at the plant. This has provided South Gippsland Water with a 72% reduction in overall energy costs, which will pay for the upgrade within a few years of operation.
The Importance of Positive DO Conditions
Accomplishing maximum BOD removal processing rates in a facultative biological treatment system is dependent on maintaining positive DO at all times. With positive DO conditions, the aerobic bacteria will perform at their maximum for a given water temperature. Additionally, odours can be 100% buffered/stripped by an oxygen-rich water column.
Gurney Environmental completed the installation of the primarily wind-powered Accel-o-Fac® wastewater treatment system upgrade for South Gippsland Water in mid 2015. After a year of operation, managers of the wwtp have provided the results of typical DO profiles now being accomplished with dramatically reduced energy, and the results are impressive. The high residual DO levels being maintained by the Accel-o-Fac system now allow the original electric aeration to be shut off for much of the time through the use of a DO controller.
Example – New Construction Project With Negligible Operating Costs for a Decade
Selecting The Best “Total Life” Options
The Accel-o-Fac® wastewater treatment plant for Holkham Hall Estate also serves the Victoria Inn and village at Holkham in Norfolk and has been treating sewage since the spring of 2006 with almost no significant ongoing operating costs.
The Holkham Estate, owned by the Earl of Leicester, includes the Victoria Inn, which is very popular with tourists visiting this part of the country. Previously, the village had been served by septic tanks requiring regular emptying. The Estate had a choice of either sending the sewage to the nearby water company's treatment works via pipeline, remain on septic tanks or treat their own wastewater. The appeal of the unique Gurney Environmental Accel-o-Fac® solution was low energy, no sludge or odour, and effluent water of a quality appropriate for either discharge or potential irrigation reuse on the Estate.
Simple, Low Maintenance Operation
After careful consideration of options, the Estate elected to use the Accel-o-Fac® windpowered system from Gurney Environmental to keep ongoing operating and total lifetime expenses (TOTEX) at a minimum. The plant also includes a simple Septic Reception Station to accommodate septic tanks from the Estate. All septage and solids are transferred to the new Accel-o-Fac® primary cell for treatment and digestion of the sludge. The system is simple, odour free and inexpensive to operate.
One of the key benefits of the system for Holkham was the need for very little operator attention. There has been almost nothing for an operator to do at the plant this last decade short of mowing the grass in the summer. Equipment maintenance includes inspections every 3-4 months. Not much else is required, making the operator's job truly part time!
Example – Australian Water Company Addresses Overloaded WWTP With Wind-Powered Accel-o-Fac®
Australian Water utility, GWM Water, completed the installation of an Accel-o-Fac® upgrade to their WWTP at Donald, Victoria using Gurney Environmental’s wind-powered SERIES 3 mixer/aerators on 29 October 2018.
Previously Anoxic/Septic, Overloaded Primary Treatment Cell
Prior to installation of the Accel-o-Fac® retrofit, the WSP primary cell at Donald, Australia was loaded well above what natural reaeration could keep up with (see data block). The pink colour indicated the presence of pink sulphur-producing bacteria indicating anoxic/septic conditions. When the BOD loading exceeds the ability to maintain aerobic conditions within a treatment cell, the powerful aerobic and facultative bacteria become dormant and no longer perform healthy rates of BOD/TSS removal, odour control, sludge digestion and disinfection.
Healthy, Well-Performing Primary Treatment Cell After Retrofit
The installation of the highly-sustainable Accel-o-Fac® retrofit utilising the wind-powered SERIES 3 Aerators/Mixers restored surplus dissolved oxygen (DO) in the upper portion of the primary cell, thereby activating strong aerobic and facultative BOD/TSS processing, odour control, ammonia-nitrogen removal, sludge control and disinfection. By restoring the upper two biological zones — the aerobic and the facultative — the bottom anaerobic zone can now begin proper digestion of all biosolids, thereby eliminating extra accumulated sludge.
For decades, Accel-o-Fac® has proven capable of turning around poorly performing lagoon-based WWTPs, both municipal and industrial, and doing so with zero-to-low energy and almost no manpower or ongoing maintenance requirements.
Watch The Videos
PRIVACY NOTICE: For videos, we use YouTube's "no-cookie" privacy mode in compliance with our Privacy Policy. However, if you have been to another Google site or a site that uses any of Google's many embedded services, you may already have cookies from Google that will be "discovered" by YouTube (a part of Google) when you play a video. We cannot block those existing cookies.
Suitable for Large, Medium and Small Populations
Accel-o-Fac® is modular and can be scaled to handle any size flow and population. The modular design allows phased construction or multi-location options.
Mechanically & Biochemically Simplified For Reliability, Low OPEX & Capital Equipment Longevity
Accel-o-Fac® is a high-process-rate wastewater treatment system that has been well proven for decades with a variety of municipal and industrial wastewater applications in all types of climates. Accel-o-Fac® employs an advanced and optimised form of a completely biological "accelerated"™ facultative treatment process that adjusts to handle large variations in flows and loadings. Accel-o-Fac® incorporates fast and easy construction techniques, uses little energy, requires exceptionally simplified operator skills, almost no maintenance, and yet turns out effluent quality that can be superior for reuse and irrigation.
Accel-o-Fac® Offers Clear Benefits

Stainless Steel
Accel-o-Fac® system components are mostly all stainless steel and designed to last the life of the wwtp with virtually no ongoing, costly maintenance or capital equipment replacements.

Little Routine Maintenance
The only routine maintenance for the entire Accel-o-Fac® wwtp is checking the auto-lubrication cartridges every 3-6 months. The result is incredibly low ongoing operating costs over the 20-year life of the wwtp.

Site Operations
Accel-o-Fac® wwtp's require no routine operator intervention. Day-to-day facility operations are reduced to virtually lawn mowing and other general upkeep. The Accel-o-Fac® system will automatically resolve shock and peak flows, self-digests the sludge, doesn't require screening or other labour-intensive operations or costly equipment.

Energy-Free Aeration
Windpower provides up to 100% of the energy needed for wastewater processing with an Accel-o-Fac® wwtp. Unique wind powered SERIES 3 aerator/mixers have been proven in severe wastewater treatment applications for decades, providing aeration, process acceleration and biological optimisation. An optional electric backup Motor Kit is available activated by wind speed. Cost savings in electricity alone can often pay for entire installations within 2–3 years. Accel-o-Fac® systems process intense wastewater but do so at incredibly low cost.

High Quality Effluent
Water from Accel-o-Fac® treatment systems not only meets rigid standards, it is also better in overall quality due to advanced stabilisation of all biochemistry. This makes it ideal for water reuse options.