Introduction
In the moving bed bio reactor mbbr (MBBR) system of wastewater treatment plants, microorganisms attached to the surface of the media help treat wastewater. Their activity and efficiency directly impact the overall treatment efficiency of the system. As a professional water treatment solution provider, AquaSust will explore with you how to better cultivate these microorganisms to optimize system operation.
Pattern of Microbial Formation
The biofilm formation on MBBR carriers is a gradual process, mainly divided into the following stages:
1. Initial Stage (1-2 days): The media surface begins to adsorb organic matter in the water, creating conditions for microbial attachment.
2. Microbial Colonization (3-7 days): The first batch of bacteria starts to settle and secretes viscous substances to strengthen the foundation.
3. Formation (1-2 weeks): Microorganisms with different functions gradually migrate in, forming a complete treatment system.
4. Operation (after 2 weeks): The biofilm reaches an appropriate thickness and structure, maintaining a stable working state.
Factors Affecting Microbial Activity in MBBR Media
(1) Oxygen Availability
In the MBBR system, oxygen supply is mainly achieved through aeration. When oxygen is sufficiently available, aerobic microorganisms can rapidly perform aerobic respiration, generating substantial energy to promote their growth, reproduction, and faster degradation of organic matter.
(2) Wastewater Composition
Organic substances in wastewater, such as carbohydrates, proteins, and fats, serve as nutritional sources for microorganisms. Microorganisms can synthesize cellular substances from elements like nitrogen and phosphorus. When the nutrient ratio in wastewater is unbalanced, microorganisms may be unable to metabolize normally. For example, heavy metals and phenolic compounds can damage the biofilm structure and reduce microbial activity.
(3) Media Pore Size
When the pore size of MBBR media is too large, although more water can flow through the pores, microorganisms find it harder to attach to the media surface. Larger spaces are not conducive to microbial attachment and metabolism.
(4) PH Value
Under suitable pH conditions, microbial metabolic activities are vigorous, enabling the formation of a stable biofilm. The pH range is generally 6.5 ~ 8.5. Most bacteria thrive in neutral or slightly alkaline environments, while fungi are more adapted to acidic conditions.
(5) Temperature
Within the appropriate temperature range, the formation and renewal rate of the biofilm increases with temperature. But excessively high temperatures can damage microbial cell structures and enzyme activity, leading to microbial death.
(6) Aeration Rate
The aeration rate affects oxygen supply, as well as the stirring intensity of water flow and the movement state of the media. An appropriate rate ensures that MBBR media flows sufficiently in water, allowing microorganisms to contact the wastewater. It also timely removes metabolic products from the surface of the microbial film, aiding biofilm renewal.
(7) Hydraulic Retention Time (HRT)
Hydraulic retention time refers to the average residence time of wastewater in the MBBR reactor. A longer HRT means more reaction time between wastewater and microorganisms, enabling the removal of more pollutants. However, this occupies more space in the reactor and reduces the total amount of wastewater treatment.
Conclusion
By creating a suitable working environment for microorganisms and controlling relevant factors, your MBBR system can operate more stably and efficiently, reducing organic matter in wastewater and improving water quality.
AquaSust - Your Trusted MBBR Media Facory
As a specialist in the water treatment field, AquaSust supplies customers with MBBR media featuring a large specific surface area and durability. From project customized design with our mbbr calculator to the maintenance stage, we provide technical support throughout. Contact AquaSust to upgrade your water treatment plan!