Choosing the right biological treatment systems Australia for your application is very important because pharmaceutical, chemical and other related industries produce a lot of wastewater in their cleaning and production process. The characteristics of the wastewater are diverse and may include toxic substances and minimally biodegradable substances or both. To protect our environment, wastewater should be treated to reduce pollutant concentrations before it can be allowed into the environment or municipal treatment plants for further treatment.

Compared to physical and chemical methods, biological processes are very efficient and economical options when the wastewater contains biodegradable pollutants. Biological treatment processes are used in a wide range of applications to remove suspended organic substances.  The treatment systems also use phosphorus and nitrogen removal. There are two categories of biological treatment – attached growth and suspended growth processes.

In suspended growth processes, the most widely used process is the activated sludge while the attached growth process can provide the same treatment capacity in a smaller footprint in a less moving bed biofilm reactor.

The first moving bed biofilm reactor (MBBR) was installed in Norway in 1989. Nowadays, as regulatory restrictions continue getting more stringent, MBBR technology is becoming more popular as it is flexible. An MBBR system uses plastic media in different configurations to provide a high surface area for carrying the biomass that treats the wastewater.

Basic process comparison

There are different types of biological treatment plants and to choose the right one for your application, it is essential to compare their processes. Activated sludge has been used in its original form and in other modifications. There are 3 basic components in this process – the biological reactor where microorganisms responsible for the treatment are kept and a clarifier for separating solids from liquids. The third component is the recycling system for returning the removed solids from the separation process back to the reactor.

Activated sludge is commonly used in biological treatment processes and it produces high-quality effluent. However, it is more sensitive than the MBBR to shock toxic matter and loads. The system is typically associated with instability issues of the biomass such as a sludge bulking. Skilled operators are needed to check that the returned sludge is active and adjust the operating conditions to react to various changes immediately.

When it comes to an MBBR system, the biofilm is usually attached and grown into the plastic media’s surface. The biofilm and media are retained in the reactor. Only a small portion of sloughed-off biofilm exists in the MBBR tank with the liquid. There is no need for sludge recycling in the MBBR system.

Choosing the best approach

Different biological treatment systems Australia have their advantage and disadvantages. When selecting the best process, it is important to consider economical and technical factors. The decision should be made based on two aspects. The right process is determined by the wastewater characteristics, available plant space, discharge requirements and the allocated budget. It is also important to consider the presence of persistent and toxic substances.