CostsCAPEX and 20-Year OPEX

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sustainability badge webAt Gurney Environmental we belive that true sustainability means that the cost to construct and operate a wastewater treatment works must be realistic and affordable. We also believe that it is our obligation to drive down those costs by using our experience, engineering expertise and knowledge of the available science and technologies. We always look at how we can deliver the effluent results required, but do so at the absolutely minimal possible costs both initially and ongoing by delivering environmentally friendly solutions with the benefit of large CAPEX and OPEX savings.

Dramatically Lower CAPEX & OPEX

Drive down the cost to treat wastewater with incredibly low ongoing OPEX.

How our Technologies cut costs.


More Biochemical, Less Mechanical

By employing a much more biological underlying process — the facultative biological process — significant costs can be eliminated in both the initial capital costs (CAPEX) of construction and equipment and the ongoing 20-year operating costs (OPEX). Facultative processing – a free gift of nature – can stabilise wastewater more thoroughly than standard mechanical treatment, and do it for a fraction of the cost and complexity.

Advanced methods developed and used by Gurney Environmental enhances the natural facultative biological process's ability to fully stabilise wastewater while simultaneously self-digesting all incoming sludge, all without odour.

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Using a pure biochemical, natural process with supplemental process enhancing technologies provides 1) a massive aerobic processing section, 2) a specialised facultative bacterial zone, 3) plus a full anaerobic sludge digestion section for total 100% on-site treatment. Additionally, special attached biofilm technology is available from Gurney Environmental for further polishing of effluent. This fundamental difference creates a major difference in initial costs and ongoing 20-year operating and maintenance costs.


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Windpowered Aeration & Optimisation

Discoveries made through decades of focused research underscored that the facultative processing of wastewater could be "accelerated" and "pushed" far beyond what had been previously thought through the use of innovative, zero-to-low energy windpowered aeration and optimisation units.

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By optimising the entire water column within a treatment cell, while simultaneously increasing the residual oxygen supply, dramatic increases in loading and processing rates and performance can be achieved, but with little energy, capital cost or ongoing manpower needs. Even the performance of the anaerobic sludge digestion zone is enhanced by the SERIES 3 units, thus providing a steady-state sludge digestion condition.

The SERIES 3 aeration/mix units by Gurney Environmental are used as key components in both the Accel-o-Fac® and Aero-Fac® systems. The units are also used to supplement other forms of aeration to improve performance and reduce operating costs. In many cases, the windpowered units can actually replace existing mechanical aeration. Maximum processing. Little energy. No odours. No sludge. A result of harnessing the laws of nature and enhancing that performance.


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Simplified, Robust Mechanicals

When supplemental aeration is required beyond the capabilities of the windpowered SERIES 3 units, Aero-Fac® systems employ powerful low-DO-activated diffused air systems. However, these diffused air systems differ significantly. The differences are so dramatic that they make a very large difference in the monthly, annual and 20-year operating costs and manpower requirements. These systems can operate at up to 85-95% less than typical activated sludge options.

SERIES 3 Surface Units — Typical aerators require significant maintenance and have relatively short lifetimes. The SERIES 3 units require almost no ongoing routine maintenance other than a lube pack change every few months. The units can last the life of the facility with minimal, very basic inspections.

Blowers — Typical high-pressure PD compressors used for diffused air systems generate heat, have a significant wear factor (short life) and require routine maintenance in order to avoid catastrophic failure. Aero-Fac® systems employ low pressure fan blowers that have an almost unlimited lifetime and require almost no routine maintenance.

Diffusers — Aero-Fac® diffusers are 100% stainless steel, require no routine cleaning, inspections or maintenance, have no membranes to wear out, clog or degrade performance and can last the life of the facility. Eliminating diffuser and PD compressor maintenance and replacements dives down costs dramatically.


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Intelligent Process and Equipment Engineering

The deeper the cell, the larger the reactor for processing more waste within a given footprint. However, maintaining uniform surplus dissolved oxygen throughout the water column, whilst not disturbing the critical bottom facultative and anaerobic biological stabilisation layers, is a challenge. Overly aggressive mixing and aeration can destroy the entire facultative process whilst also putting solids into suspension, thereby requiring additional oxygen for processing. This also allows solids to pass from the primary stage into follow-on stages, thereby thwarting the built-in anaerobic sludge digestion of a capped, undisturbed bottom zone.

Gurney Environmental has developed unique, time-proven equipment that can allow for deep cells with fully aerobic conditions throughout the water column without disturbing the critical layering of the facultative process itself. This unique technology also employs intelligent design by gently bringing the lowest DO water from the bottom up to the surface where it can uptake oxygen at a far greater rate than typical surface water (Henry's Law).


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Eliminate Sludge Regulation, Storage & Handling

Handling solids requires significant initial capital costs plus ever-escalating ongoing costs. By eliminating the need to screen and separate solids at the inlet works, by eliminating the energy required to break down the biosolids aerobically, by eliminating the cost to recapture, dewater, store and dispose sludge, significant costs savings are achieved.

But even further, sludge handling and disposal requires compliance with regulatory issues. Hauling away solids requires access roads to the works and tanker movements to and from the facility. While today's costs can be determined fairly precisely, no one can reliably estimate what future costs will be for the life of the wwtp due to ever changing thoughts on sludge disposal and tanker movements.

Gurney Environmental's technologies simply provide a dramatically "greener", lower-carbon-footprint overall wwtp with lower initial and ongoing costs, plus controllable costs well into the future.


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Reduced Manpower & Expertise

The more complex the process and equipment at a wwtp, the more manpower training and cost is required. Complex systems simply require more people, better trained people and more expensive people. And labour costs are an inflationary item that is hard to forecast for future budgeting. No one can reliably predict over a 20-year life of a wwtp exactly what labor costs will be. Thus, estimates of 20-year OPEX for typical activated sludge and extended aeration treatment works are hard to reliably calculate.

Systems designed by Gurney Environmental require, in some case, no full time manpower. Even on larger facilities, the manpower requirements are a fraction of typical wwtp's. And just as importantly, the skill level is far less to operate and maintain an Accel-o-Fac® or Aero-Fac® wwtp.

Added to the other major costs savers, it is clear why systems designed and delivered by Gurney Environmental can operate at 85-95% less than many other alternatives. These systems literally pay for themselves just through savings as compared to other alternatives.


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Simplified Construction Techniques

The Gurney Environmental systems require far less complex construction that can be completed within a much shorter time frame. A simple cut-and-fill earthen basin using the cut to create the berms can be built within a shorter time.

There is far less concrete and complex construction involved. This not only lowers the initial costs and reduces time on site, but also leaves less for environmental degradation and future replacement.

Fast construction. Less costly construction. Longer durability. It all adds up to a lower cost now and into the future.

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Extraordinary Flow Flexibility

Seldom does a wwtp see a steady, uniform flow. Throughout different day parts, flows can change dramatically. Seasonal variations can cause flows at many times normal flows up to 10-20 times normal. And if a treatment works is being built in an area where future growth is expected, or where other areas are to be added in at a later date, it can be impossible to design for such flow changes.

Accel-o-Fac® and Aero-Fac® systems have for years been used at sites where massive flow swings commonly occur. Little to no operator intervention is required to handle these peak-and-valley flows.

This also allows for extremely flexible initial designs for a new wwtp.

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Shock Load & Odour Buffering

A common occurrence is odour generated by septic influent. Raw sewage can cause serious issues for anyone located near a wwtp. Likewise spikes in loading can upset typical processes requiring operator intervention and sometimes result in poor discharges. Shock buffering can be costly in typical facility designs.

Systems from Gurney Environmental easily handle shock loads and 100% control all odours at a wwtp. Gurney Environmental even offers a specialised system, the Aero-Fac PTS or Primary Treatment System for use in front of a normal filter plant. The PTS system self digests all the solids, controls all odour and buffers even the largest spikes in loading. The ability to do this dramatically cuts both initial capital costs as well as ongoing costs for a wwtp, plus provides for a much more real-world operations of the wwtp. Sustainable. Practical. And less costly.


100% Complete On-site Treatment

Both Accel-o-Fac® and Aero-Fac® wwtp's provide complete on-site treatment including the removal and digestion of all biosolids. Energy and manpower requirements are a fraction of activated sludge plants. Maintenance is minimal and capital equipment lasts far longer. Using 40+ years of intensive research into lowering the total life cost of wastewater treatment, Gurney Environmental has the experience and proven track record of successes to provide extremely robust and low CAPEX, OPEX and TOTEX, truly sustainable systems unmatched in the industry.

Scalable, Modular Design For Any Size WWTP

Both Accel-o-Fac® and Aero-Fac® utilises multiple cells in parallel trains and in series. Each cell or stage reduces BOD by about 80-85% (water temperature dependent). Parallel trains provide for a modular approach to accommodate larger flows with complete and predictable scalability.

Examples of Modular Scaling

Comparison of OPEX in Wastewater

All Gurney Environmental systems come with design assistance and follow-on operational support.

  • Activated Sludge
  • OPEX 100%
  • High CAPEX
  • High initial cost and complex, expensive ongoing energy & operations costs
  • Shock & Peak Loads Can Upset Process
  • Prescreening Equipment Generally Required
  • Aeration Required for Both Oxygen & Mix
  • Clarifier Required
  • Can Have Odour Issues
  • Sludge Handling & Regulation Required
  • High Consumables/Chemicals
  • High Level of Operator Attention/Expertise
  • Annual Maintenance*
  • ?????
  • * 4000 m3
  • Aero-Fac®
  • OPEX –85%
  • Low CAPEX
  • Low initial cost and dramatically lower ongoing energy & operations costs
  • Easily Accepts Shock & Peak Loads
  • No Prescreening Equipment Required
  • Aeration Required only for Oxygen Demand
  • No Clarifier Required
  • Odour-Free wwtp
  • No Sludge Handling & Regulation Required
  • Few Consumables/Chemicals
  • Very Low Operator Attention/Expertise
  • Annual Maintenance*
  • £882/yr est.
  • * 4000 m3
  • Accel-o-Fac®
  • OPEX –95%
  • Lower CAPEX
  • Low initial cost and dramatically lower ongoing energy & operations costs
  • Easily Accepts Shock & Peak Loads
  • No Prescreening Equipment Required
  • Aeration Required only for Oxygen Demand
  • No Clarifier Required
  • Odour-Free wwtp
  • No Sludge Handling & Regulation Required
  • Few Consumables/Chemicals
  • Very Low Operator Attention/Expertise
  • Annual Maintenance*
  • £532/yr est.
  • * 4000 m3
  • WS Ponds
  • OPEX –97%
  • Lowest CAPEX
  • Low initial cost and low ongoing energy & operations costs, but several common problems
  • Problems With Shock & Peak Loads
  • Prescreening Equipment Sometimes Required
  • No Aeration used for Oxygen Demand
  • No Clarifier Required
  • Can Have Odour Problems
  • Possible Future Sludge Removal Required
  • Few Consumables/Chemicals
  • Very Low Operator Attention/Expertise
  • Annual Maintenance*
  • £200/yr est.
  • * 4000 m3

Both Aero-Fac® and Accel-o-Fac® can be designed as modular units and can accept a wide range of flows and loading. Both Systems can be designed as "new build" or retrofit to existing wwtp's.

Interested? Want to contact Gurney Environmental?

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