More active biomass in the same reactor volume
Hexor HPU is a hydrophilic reticulated foam biocarrier developed by Haizer to intensify biological wastewater treatment in moving bed reactors (MBBR) and hybrid systems (IFAS).
Its macroporous structure provides high surface area for biomass growth, allowing more compact plants with fast start-up and simple operation. It is the solution for developments and municipalities that need quality treatment in reduced space.
How the media works inside the reactor
Kept in continuous suspension by aeration, each cube works as a micro-reactor of attached biofilm. Biomass stays retained in the moving bed — it is not washed out with the effluent — and the media remains active even under load fluctuation.
Biomass attached inside the foam, protected from hydraulic washout.
Pores of 0.11 mm and 85% voids ensure substrate and oxygen exchange.
Practically neutral density with mature biofilm — circulation with low energy.
Six reasons to specify Hexor
High surface area
Macroporous structure with high surface area for biomass growth, validated by independent morphological characterization.
Fast biological start-up
Hydrophilic matrix with practically immediate wetting — colonization from the first days of operation.
Reduced footprint
High treatment capacity per installed volume, ideal for compact plants and projects with area restrictions.
Simple operation
Low maintenance and stable behaviour, suited to plants operated by non-specialized teams.
Resilience to load peaks
The internal structure preserves microbial reserves that restore performance after peaks and load fluctuations.
Validation and warranty
Product characterized in a federal university laboratory and covered by a 5-year Haizer warranty against manufacturing defects.
Composition and geometry
| Feature | Hexor HPU |
|---|---|
| Base material | Modified hydrophilic polyurethane |
| Structure | Three-dimensional reticulated foam with interconnected open cells |
| Commercial geometry | Cubes 20 × 20 × 20 mm (tolerance ± 1 mm) |
| Actual dry dimensions (measured average) | 18,62 × 18,61 × 18,57 mm · CV < 2% |
| Average geometric volume | 6.44 cm³ per piece (CV 2.9%) |
| Colour | White when dry · darkens progressively as the biofilm matures |
| Application | MBBR reactors and IFAS systems |
Physical and hydraulic properties
| Hydrated apparent density | 760,5 kg/m³ |
| Water absorption (by mass) | 1.560% |
| Volumetric expansion in water | 22.7% on average (range 10.6 to 33.3%) |
In operation, with a mature biofilm, the density of the media is approximately neutral — in equilibrium with water.
Surface properties and pore structure
| Specific area adopted in design | 2,500 m²/m³ — Haizer criterion, conservative |
| Estimated effective specific area | 10,659 m²/m³ (SEM characterization) |
| BET specific surface area | 20 m²/g |
| Structural void fraction | 85% |
| Average pore size | 0,11 mm |
| Average structural filament diameter | 0,035 mm |
The value of 10,659 m²/m³ results from morphological characterization by scanning electron microscopy (SEM). For design purposes, Haizer currently adopts the conservative value of 2,500 m²/m³ — the margin between the two is the design safety reserve.
Mechanical properties
Tests according to adapted ASTM D3574.
| Test | Dry state | Hydrated state |
|---|---|---|
| Initial compression modulus | 14,2 ± 2,6 kPa | 6,8 ± 1,5 kPa |
| Stress at 25% strain | 18,9 ± 3,3 kPa | 9,7 ± 2,1 kPa |
| Stress at 50% strain | 37,6 ± 5,4 kPa | 21,4 ± 3,8 kPa |
| Stress at densification | 82,1 ± 9,7 kPa | 58,6 ± 7,2 kPa |
| Elastic recovery (50% compression for 22 h) | 87,3% | 81,1% |
Operational specifications
| Parameter | Recommended value | Operating limit |
|---|---|---|
| Filling ratio | 10 to 20% | Maximum 30% |
| pH range | 6.5 to 9.0 | 6.0 to 10.0 |
| Temperature range | 10 to 40 °C | 1 to 50 °C |
Recommended removal rates
g /m³ of media · day
| Parameter | Recommended range | Base references |
|---|---|---|
| DBO₅ | 500 – 2.500 | Nhut et al.; Guo et al. |
| DQO | 800 – 4.000 | Proportional (~1.6) |
| N-NH₃ | 100 – 500 | Zhang et al.; Magdum |
Independent validation and 5-year warranty
Hexor HPU was experimentally characterized by the Biological Processes Laboratory of the Federal University of ABC (LPB-UFABC), under the technical responsibility of Prof. Dr. Rodrigo de Freitas Bueno — validation by an independent institution confirming the physical properties of the material.
Haizer, as importer and legal entity responsible for the product in the Brazilian market, offers a 5-year warranty against manufacturing defects and provides technical guidance during project specification.
Physical, hydraulic, surface (SEM, BET) and mechanical (adapted ASTM D3574) tests in a federal university laboratory.
Technical guidance for sizing, definition of filling ratio and compatibility with the reactor.
Let's size your WWTP with Hexor HPU
Send the reactor and influent load data. Haizer's technical team will respond with the indicated filling ratio, the required media volume and the quote.