Municipal Wastewater Treatment

Municipal wastewater treatment is becoming more and more expensive due to population growth, increased discharge standards and rising energy costs. 




The Context

Municipal wastewater treatment challenges:

- Increasing Populations

- Increased Discharge Standards

- Rising Energy Costs

- Cost of Refurbishment / Retrofit

- Rising Sludge Disposal Costs

Aeration comprises 60% of energy costs in a typical activated sludge treatment process, in addition to this, there is a large capital cost for land and equipment required in the treatment of wastewater. 

Key Benefits


Key Advantages of OxyMem MABR

Add Capacity Today:

OxyMem MABR is delivered in a modular design and can be scaled incrementally to service any municipal requirement. Adding biological capacity has never been easier. MABR can achieve incremental capacity increase without additional tanks. OxyMem changes the asset management with advanced IFAS MABR which is a drop in solution.

Rapidly Increase WWTPs Capacity with Drop in MABR:

MABR can offer instant and incremental biological expansion of existing assets (See example 1 below).

Reduction in Energy Costs:

OxyMem's 4th Generation MABR uses up to 7 times less energy (14kg/O2/kWh) than Activated Sludge (AS), 15 times lower than AS

Small Footprint:

Space is a one of the most precious resources in an urban environment. OxyMem MABR is 4 times smaller, in terms of footprint, than Conventional Activated Sludge (See Example 3 below).

Generation 4 MABR

Generation 4 MABR


Example 1: Capacity Expansion Can be Incremental

Drop-in expansion of biological plant capacity (IFAS style deployment for overloaded or under performing plants). MABR can be delivered without draining the tanks or interfering with the existing process.

Sweating the Assets with MABR

- Deliver 50% additional treatment capacity in a matter of weeks without draining the tanks

- Add up to 50% more capacity (as you need it) to the WWTP by retrofitting a conventional AS system is costly, time-consuming and requires 187.5 m² available space to be built on.

- OxyMem MABR module gives a unique possibility to instantly increase the capacity of the existing AS WWTP without creating any additional footprint. 

- Energy advantages of adding OxyMem MABR as a retrofit.
Increasing the capacity of the existing WWTP by 50% corresponds to 50% rise in the energy costs increase when upgrading with AS system. In the case of retrofitting with OxyMem MABR, operational energy expenditure for a year is €1901 versus €8950 spent additionally for the new AS system.

Example 2: Energy Costs Significantly Reduced

When looking closer at the operational costs of the municipal 10 000 PE WWTP, OxyMem MABR requires only a fifth of the energy used by the conventional AS installation. (Based on a price of the energy set at 0.1€/kWh, savings of €14,000 per year).

The indicative energy usage data of OxyMem MABR can be explored further in the Severn Trent case study.  







Example 3 - Footprint

When a wastewater treatment plant (WWTP) with a size of 10 000 PE (people equivalent) and flow capacity of 1500m³/day is taken as an example, OxyMem MABR delivers supreme water quality by taking up only 104m² in comparison to 375m² footprint required to have a conventional activated sludge (AS) plant operating with a similar treatment capacity.

Employing OxyMem’s MABR takes over 3.6 times smaller footprint. 

It is possible, as OxyMem MABR module with 500m working volume successfully replaces 1500m³ of AS installation. As depicted in the process flow diagram below (Figure 1a), the anoxic and aerobic combined phase tank is accompanied with a settler unit.

Key Benefits

OxyMem MABR can significantly improve discharged water quality, if placed after the conventional municipal wastewater treatment system, taking up minimum space. It can also act as a secondary treatment, for example supporting lagoon type Wastewater treatment plants.

Key Drivers for Energy Savings      

- OxyMem MABR in comparison to AS system requires less aeration energy. The system does not rely on the pressure difference to transfer the oxygen and the pressure drop over the length of the module is so low that it is possible to operate blowers with low discharge pressure (150 – 200 mbar).    

- OxyMem MABR includes innovative reverse airlift technology to provide a maximum wastewater stream mixing within the module, so there is no need for energy expenditure for mixing as it is necessary for the anoxic tank of the AS WWTP.    

- In OxyMem MABR module fixed biofilm growth on the membranes limits the unwanted excess sludge production. Consequently, the sludge return is redundant, and there is no energy spent to run pumps for returning it, like in AS WWTP where it is transferred from the settler back to the bioreactor.    

The indicative energy usage data of OxyMem MABR can be explored further in the Severn Trent case study.