How Wastewater Treatment Plants Should Adjust Operations During High Temperature Seasons
How High Temperature Affects Wastewater Treatment Plants
As temperatures rise across many regions, Wastewater Treatment plants face more pressure in daily operation. Hot weather can accelerate biological reactions, increase oxygen consumption, intensify odor, promote sludge decay and make influent quality more unstable.
For municipal wastewater plants, industrial Wastewater Treatment stations and centralized treatment facilities, summer operation is not only about higher water temperature. It also means higher risk of dissolved oxygen shortage, sludge floating, foaming, odor complaints and unstable effluent quality.
For plants located in South Asia, Southeast Asia, the Middle East, North Africa, Southern Europe, Mexico, the southern United States and other hot climate regions, high temperature season should be treated as a key operation period.
Main Problems During Hot Weather
Higher Oxygen Demand
When water temperature increases, microorganisms become more active. This can improve biodegradation in some cases, but it also increases oxygen consumption.
At the same time, warm water holds less dissolved oxygen. This means the biological system may need more aeration to maintain stable DO levels.
If aeration is insufficient, the plant may experience ammonia nitrogen increase, black sludge, odor, poor settling and unstable effluent.
Faster Sludge Decay
High temperature accelerates sludge metabolism and endogenous respiration. If sludge stays too long in the system, it can become old, loose and easy to float.
This is common in secondary clarifiers, sludge storage tanks, thickening tanks and sludge dewatering areas.
Stronger Odor Generation
Hot weather increases the release of hydrogen sulfide, ammonia and other unpleasant gases. Odor problems are especially common in inlet areas, equalization tanks, sludge tanks, dewatering rooms and covered channels.
If odor is not controlled, it can cause complaints from nearby communities and create an unsafe working environment for operators.
More Foaming and Floating Sludge
High temperature, organic shock load, low dissolved oxygen and surfactants can all increase foaming risk. In some plants, foam becomes more serious in aeration tanks, biological reactors and sludge treatment units.
Floating sludge may also occur in secondary clarifiers when denitrification happens inside the settled sludge layer.
More Unstable Influent Quality
During hot seasons, wastewater in collection systems and equalization tanks can ferment faster. Industrial wastewater may also become more concentrated due to water evaporation or production changes.
This can lead to higher COD, stronger color, increased suspended solids, stronger odor and unstable pH.
Recommended Operation Adjustments
Increase Aeration Management
Wastewater plants should check dissolved oxygen more frequently during high temperature periods.
The aeration system should be adjusted according to actual DO, ammonia nitrogen and biological activity. Blowers, air pipelines and diffusers should also be inspected to avoid uneven aeration.
For biological treatment systems, stable oxygen supply is one of the most important measures during summer operation.
Control Sludge Age and Sludge Discharge
High temperature usually requires closer control of sludge age. If sludge age is too long, sludge may become old and easy to decay.
Operators can consider increasing excess sludge discharge frequency and reducing sludge retention time in storage tanks.
The plant should monitor MLSS, SV30, SVI, sludge color, sludge smell and clarifier sludge level.
Strengthen Equalization Tank Management
Equalization tanks are important during hot weather because they help reduce influent shock loads.
Plants should improve mixing, avoid dead zones and prevent long retention time. If the wastewater has strong odor or dark color before biological treatment, pre treatment may be needed.
Adjust Chemical Dosing Based on Jar Test
High temperature may change coagulation and flocculation performance. Plants should not rely only on previous dosing habits.
Jar tests should be carried out when influent COD, color, turbidity, pH or suspended solids change significantly.
Bluwat can support plants with chemical selection and laboratory test guidance based on wastewater samples and actual treatment targets.
Bluwat Product Solutions for High Temperature Wastewater Treatment
Bluwat PAC for Coagulation and Suspended Solids Removal
Bluwat Polyaluminium Chloride is widely used for municipal wastewater, industrial wastewater and pre treatment systems.
It helps destabilize colloids, reduce turbidity, improve clarification and support Solid Liquid Separation.
In hot weather, PAC can be used in pre treatment or advanced treatment to reduce the burden on the biological system.
Bluwat PAM for Flocculation and Sludge Dewatering
Bluwat Polyacrylamide is available in anionic, cationic and nonionic grades.
It helps form larger and stronger flocs, improve settling speed, reduce suspended solids and improve sludge dewatering efficiency.
During high temperature seasons, PAM can help plants manage unstable sludge settling, higher suspended solids and increased sludge production.
Bluwat BWD 01 Water Decoloring Agent for High Color Wastewater
For textile dyeing wastewater, printing wastewater, paper mill wastewater, pigment wastewater and other colored industrial effluent, high temperature may make color and COD fluctuation more obvious.
Bluwat BWD 01 Water Decoloring Agent is a liquid organic polymer used for color removal, Cod Reduction and coagulation improvement.
It can be used together with PAC and PAM to achieve better clarification and color removal performance.
Bluwat PolyDADMAC for Charge Neutralization
Bluwat PolyDADMAC is a strong cationic polymer used for charge neutralization, coagulation support and clarification.
It is suitable for many wastewater systems where colloidal particles, organic matter or fine suspended solids are difficult to remove.
For plants facing unstable influent during hot seasons, PolyDADMAC can be considered as part of the chemical treatment program.
Bluwat Defoamer for Foam Control
Foam can become more obvious in hot weather, especially in aeration tanks, biological treatment systems and sludge treatment areas.
Bluwat defoamer products can help reduce foam quickly and improve operation stability.
Bluwat Plant Based Deodorizer for Odor Control
Odor control is one of the most important tasks during high temperature periods.
Bluwat plant based deodorizer can be used in wastewater treatment plants, sludge dewatering rooms, pumping stations, garbage leachate treatment areas and other odor sources.
It helps reduce unpleasant odor and improve the working environment.
Suggested Chemical Treatment Combination
For high color industrial wastewater:
BWD 01 Water Decoloring Agent
PAC
PAM
For high suspended solids wastewater:
PAC
PAM
For unstable colloidal wastewater:
PolyDADMAC
PAC
PAM
For foaming problems:
Bluwat Defoamer
For odor problems:
Bluwat Plant Based Deodorizer
The actual product model and dosage should be confirmed by jar test and site operation data.
What Information Should Be Checked Before Summer Operation
Wastewater plants are recommended to review the following indicators before high temperature season:
Influent temperature
pH
COD
BOD
Ammonia nitrogen
Total nitrogen
Suspended solids
Color
Sludge concentration
SV30
SVI
Dissolved oxygen
Odor source
Foaming condition
Sludge dewatering performance
With these data, chemical selection and process adjustment can be more accurate.
Work With Bluwat for Hot Weather Wastewater Treatment Support
High temperature wastewater treatment requires both process adjustment and suitable chemical support.
Bluwat Chemicals provides a wide range of water treatment chemicals including PAC, PAM, BWD 01 Water Decoloring Agent, PolyDADMAC, Polyamine, defoamer and plant based deodorizer.
If your wastewater treatment plant is facing high temperature operation problems such as strong odor, floating sludge, high color, poor settling, excessive foam or unstable effluent, you can contact Bluwat with your wastewater sample and basic water quality data.
Our team can help recommend a suitable chemical program and provide jar test guidance for your treatment system.