How Does the AdvanTex^® System Work?

• The patented textile used in the AdvanTex^®  provides greater treatment efficiency and stability.
• Advantages of Textile as the Reactor medium in a PBR
• Robustness and Stability of the AdvanTex^® Treatment Process

The patented textile used in the AdvanTex^®  provides greater treatment efficiency and stability.

Textile-based packed bed filters, incorporating an engineered treatment medium, have greatly expanded packed bed technology options by incorporating a manufactured media that is easily serviced and capable of consistently producing high quality effluent. The effluent quality produced by these units is consistently superior to that discharged by the majority of our nation’s municipal treatment facilities and is ideal for many water-reuse applications, including irrigation and recycling for in-house uses.

Advantages of Textile as the Reactor medium in a PBR.

The recirculating textile PBR is essentially a bed of highly specialised textile nestled in a pre-made POD to which the effluent is uniformly dosed through a pressure distribution and spray system using a timer controlled dosing regime. These small precise doses at multiple spray sources across the reactor bed ensure even, thin film application of the effluent maximising retention times within the reactor for renovation.  This treatment process produces an almost clear and odourless effluent suitable for land treatment.  Porosity, attached growth surface area, and water-holding capacity contribute to the textile media’s enhanced treatment performance versus loading compared to gravel media PBRs.

• Porosity — The porosity of the textile media is several times greater than that of sand, gravel, and other particle-type mediums. The more porous the medium, the greater its hydraulic conductivity, the greater its air space (which enhances the capacity of passively ventilated systems and free air movement), and the greater its capacity for the accumulation of solids and biomass development.
• Surface area — Textile media can be blended with a variety of fibers to achieve relatively large total surface area per unit volume (m²/m³). In current media blends, the typical attached-growth surface area is 4-8 times greater than recirculating filter media. Expanding the biomass growth area provides a greater surface potential for air and effluent to interface and come in contact with the biomass.
• Water-holding capacity — The water-holding capacity of textile media also varies considerably depending on the media density, type of material, and blend of fibers. The water-holding capacity in textile media is also several times greater than expected in the sands and gravels used in filters. Water-holding capacity performs a key function in the treatment process. Together with the programmed dosing time and frequency, it governs the effluent retention time within the filter and ultimate effluent quality.

Robustness and Stability of the AdvanTex^® Treatment Process.

The robust treatment process, treatment reliability and stability are among the reasons for our selection of the OSI AdvanTex^®  rtPBR treatment plant over other treatment technologies. Our considerations include:

• The PBR process proposed by Innoflow Technologies is well proven both in New Zealand over 10 years and internationally over 25 years.  The AdvanTex^®  wastewater system has been designed to provide a consistently high quality effluent under variable wastewater strengths and fluctuating loads. 
• The AdvanTex^®  is considered the most robust and stable wastewater treatment plant on the New Zealand market to adequately handle fluctuating loads without adversely affecting effluent quality. The treatment plant provides a stable treatment process even under occasional shock loading without any adverse effects to the treatment plant or land application system.    The following features enable shock and variable loads to be managed:

1. During periods of low flow (i.e. few occupants), effluent from the recirculation tank continues to be dosed onto the media bed within a “closed loop” system, i.e. a 100 % recirculation rate occurs when incoming flow is zero.  This maintains the population of micro-organisms on the textile media, ready to treat larger flows when they arrive.
2. Sudden large flows are NOT dosed onto the media bed or irrigation area.  The flows are flow modulated or buffered in the septic tanks above the working effluent filters.  These filters are fitted with a specific dosing volume controlled pump, using the Biotube^®  modulation outlet holes; which release a specified flow rate to the recirculation tank.  Flow rates above the discharge rate are buffered in the tank and released during off peak times (i.e. following high usage times such as morning and evening).  Flows are also buffered in the recirculation tank prior to the rtPBR with wastewater dosed onto the textile media bed and irrigation area in a controlled fashion.  The dosing method is controlled by a timer operated pump; which means only a set volume is applied to the media bed for a set period of time over a 24 hour period, overloading therefore cannot occur without the timer override float and alarm activating.

The AdvanTex^®  treatment system is a natural treatment process that operates under passive aerobic conditions.  The micro-organisms that live on the textile media comprise the full spectrum of naturally occurring soil micro-organisms.  These microbes are supplied with a continuous source of food through the recirculation process.  As the microbes comprise numerous different species, the system will operate at optimum performance levels within hours even after extended periods of zero effluent flow into the system.  Most other systems such as aeration type plants rely on forced air to create an aerobic environment within the aeration chamber and the micro-organisms that proliferate are aerobic microbes essentially living within an inherently unstable environment (i.e. only small changes in the process can lead to upset conditions). 

The diversity of microbes in aeration plants is very limited and they do not readily adjust to a fluctuation in wastewater flows or wastewater strengths nearly as quickly as packed bed reactors.  In fact we have been advised that from start up some aeration plants require six months of operation before satisfactory performance is achieved.