The Advantages Of MBBR Treatment Process in STP

An STP plant, sometimes also referred to as a Wastewater Treatment Plant (WWTP), is a facility designed to treat and process wastewater (sewage) before discharging it back into the environment. This wastewater mainly consists of domestic sewage, along with a small amount of industrial effluent. Among the numerous wastewater treatment technologies, the Moving Bed Biofilm Reactor (MBBR) is becoming one of the mainstream processes in many STPs due to its high efficiency and flexibility. Today, we'll take a look at the MBBR treatment process and discuss how it optimizes the operational treatment effectiveness of wastewater treatment plants.

MBBR (Moving Bed Biofilm Reactor) is a wastewater treatment technology based on the biofilm method. It degrades pollutants such as organic matter and ammonia nitrogen through the microorganisms attached to the surface of suspended carriers. Its main components include:

MBBR Media

This is a plastic medium with a honeycomb structure having a high specific surface area (usually 500 - 1000 m²/m³), which provides an attachment and growth space for microorganisms. Its material is generally polyethylene or polyurethane.

Reaction Tank

The aeration system and agitation device in it are used to make the MBBR media suspend evenly and come into full contact with the wastewater.

Screen Interceptor

Prevents the carriers from being lost with the effluent.

 

The operation of the STP MBBR process can be divided into three stages:
• Biofilm Formation: When the MBBR media is put into the reaction tank, microorganisms (such as nitrifying bacteria and denitrifying bacteria) attach and grow on the surface of the media, forming an active biofilm layer.
• Pollutant Degradation: When the wastewater passes through the reaction tank, organic matter, ammonia nitrogen, etc. are adsorbed by the biofilm and decomposed into CO₂, water, or nitrogen gas by these microorganisms.
• Carrier Circulation: Through the agitation of aeration diffuser bubbles or mechanical impellers, the MBBR carriers in the water can flow continuously. They can ensure that the microorganisms and wastewater are in full contact, avoid sludge deposition, and buffer the impact load of water quality and quantity.

 

(1) Pretreatment
Before the wastewater enters the MBBR reactor, it needs to go through pretreatment to remove large - sized suspended solids, grease, sand grains, and other impurities. Common pretreatment methods include grid filtration, sedimentation in grit chambers, and oil separation. This is to prevent these impurities from clogging the subsequent treatment equipment.
(2) Biological Treatment
In the MBBR reactor, the wastewater comes into full contact with the biofilm on the suspended carriers, and the pollutants in the water are decomposed and transformed. We need to control the operating parameters in the reactor, such as dissolved oxygen, temperature, and pH value. Among them, dissolved oxygen affects the growth and metabolic rate of aerobic microorganisms. We can use an aeration system to introduce air or oxygen into the reactor to keep the dissolved oxygen concentration within an appropriate range.
(3) Post - treatment
After the wastewater is treated in the MBBR reactor, only some suspended solids, microorganisms, and other impurities remain. At this time, post - treatment is used to further improve the water quality to meet the discharge standards or reuse requirements. Common post - treatment methods include sedimentation, filtration, and disinfection.

Low Maintenance Cost: The MBBR media used in the MBBR process is mainly made of durable HDPE, which can resist the corrosion of various chemical materials. It doesn't need to be replaced as frequently as the components in the traditional activated sludge method. In addition, this process produces less sludge and doesn't require a complex agitation mechanism or reflux system.

High Biological Stability: The high specific surface area of the MBBR media provides a large number of attachment surfaces for microorganisms. A diverse microbial community, including bacteria, fungi, and protozoa, will form on its surface. This makes the microorganisms more adaptable to changes in water quality and quantity.

Small Footprint: The STP MBBR process can increase the biomass per unit volume by adding a large number of MBBR bio - fillers in the reactor, thereby achieving higher treatment efficiency. It can also integrate multiple units such as biological treatment and sedimentation in one reactor, reducing the use of connecting pipelines and the footprint.

Low Excess Sludge Production: In the MBBR process, microorganisms attach to the surface of the MBBR media to form a biofilm. There are different microbial ecological environments inside the biofilm, including aerobic zones, anoxic zones, and anaerobic zones. Some microorganisms can carry out denitrification under anoxic or anaerobic conditions, converting organic matter into harmless substances such as nitrogen gas. This can reduce the proliferation of microorganisms and the production of excess sludge.

Fast Start - Up: The MBBR media has a large specific surface area and good biocompatibility. During the start - up phase, we only need to put an appropriate amount of inoculated sludge into the reactor, and microorganisms can form a biofilm on the media in a short period. They can generally achieve stable treatment effects within 2 - 3 weeks.

 

Take a municipal wastewater treatment plant as an example. The plant originally used the traditional activated sludge method, and its effluent could hardly meet the strict discharge standards. The AquaSust team, after design and discussion, introduced the MBBR treatment process for the plant. At the same time, we adjusted the aeration volume dynamically according to real - time dissolved oxygen concentration, sewage flow rate, and other parameters to ensure that the dissolved oxygen in the MBBR reactor was stably maintained at 2 - 4mg/L. After half a year of commissioning and operation, the plant's effluent reached the national first - class A discharge standard and achieved a higher treatment capacity.

AquaSust is a well - known supplier in water treatment solutions. Our team of experts really knows their stuff when it comes to using the latest MBBR technology. We can customize it to fit your wastewater treatment plant's needs like a glove. And we're super confident we can offer you a high - performance wastewater treatment equipment.

If you want to learn more, please contact us. We're here to help you make your wastewater treatment work better!