Skip to main content

Sewage Treatment Plant - Equalization Tank Basics

Introduction

The equalization tank is a crucial component in a Sewage Treatment Plant (STP), serving as the first collection and buffering stage. It regulates the fluctuating inflow of raw sewage from bar screen chambers, oil traps, and grit separators, ensuring a steady and controlled flow to the treatment process. This tank plays a vital role in preventing system overloads during peak hours while maintaining efficient wastewater treatment. Additionally, aeration through coarse bubble diffusers helps in mixing and preventing sedimentation, optimizing the efficiency of the STP.

Equalization Tank

The sewage from the bar screen chamber and oil, grease and grit trap comes to the equalization tank. The equalization tank is the first collection tank in an STP
Its main function is to act as buffer: 
To collect the incoming raw sewage that comes at widely fluctuating rates, and pass it on to the rest of the STP at a steady (average) flow rate.
During the peak hours, sewage comes at a high rate. The equalization tank stores this sewage, and lets it out during the non-peak time when there is no/little incoming sewage.
1 The inlet pipe 
2 The sewage is collected in the tank. 
3 The raw sewage lift pumps
4 The delivery pipe takes the sewage to the aeration tank.
5 The coarse bubble diffusers are short length of tubes that have holes at regular spacing. They release large bubbles in the tank to lightly aerate the sewage, and also to agitate the mix continuously.
6 Compressed air comes though this air supply pipeline. 

Operation And Maintenance Considerations
  • Keep air mixing on at all times
  • Ensure that the air flow/ mixing is uniform over the entire floor of the tank. Adjust the placement of diffusers and the air-flow rate as needed.
  • Keep the equalization tank nearly empty before the expected peak load hours 
  • Check and clean clogged diffusers at regular intervals.
RAW SEWAGE LIFT PUMPS
1 There are two identical pumps. Controls ensure that only one pump can run at a time.
2 Both pumps have independent suction pipes. 
3 The delivery pipes from both pumps are combined in a T-shaped header. 
4 The bypass pipeline returns the excess sewage back to the tank.
5 Valves
Operation And Maintenance Considerations
  • Switch between the main and standby pump every 4 hours (approximately).
  • Check oil in the pump every day; top up if necessary
  • Check motor-to-pump alignment after every dismantling operation
  • Check condition of coupling and replace damaged parts immediately
  • Check for vibrations and tighten the anchor bolts and other fasteners
  • Check condition of bearings, oil seals, mechanical seal and replace if necessary
  • Completely drain out oil and replace a fresh as per manufacturer’s recommendation
Final Words:
A well maintained equalization tank ensures the smooth operation of the sewage treatment plant by balancing flow rates and preventing system stress. Proper airflow regulation, regular cleaning of diffusers, and systematic maintenance of sewage lift pumps are essential for optimal performance. By following routine inspection, cleaning, and preventive maintenance protocols, facility managers can enhance treatment efficiency, prevent equipment failures, and ensure a sustainable wastewater management system.

Labels

Labels:

Comments

Post a Comment

Popular posts from this blog

Comprehensive Guide to Fire Safety: Fire Triangle, Fire Control Methods & Fire Extinguishers Types

Introduction Fire is one of the most dangerous and destructive forces that can occur in homes, workplaces, and industrial settings. Understanding fire behavior, prevention techniques, and fire extinguishers is crucial for minimizing risks and ensuring safety. The Fire Triangle explains how flames sustain combustion through the presence of three essential elements: fuel, heat, and oxygen. Removing any of these elements can effectively control or extinguish a fire. Fire prevention and suppression methods focus on eliminating one or more of these factors. This article provides a detailed guide on fire control methods, fire prevention systems, and the types of fire extinguishers used for different classes of fires. Understanding the Fire Triangle The Fire Triangle is the foundation of fire science, consisting of three key components required for combustion: Fuel – Any material that can burn, such as wood, paper, gasoline, or chemicals. Heat – The energy source that raises the fuel's te...
Post a Comment
Read more

Sewage Treatment Plant - Filter Feed Pumps Types and Operation And Maintenance Considerations

Introduction: Filter Feed Pumps are essential components in industrial water treatment systems, facilitating the movement of water through filtration stages to enhance its quality. These pumps draw clarified water and direct it through the Pressure Sand Filter (PSF) and Activated Carbon Filter (ACF), which work together to remove solid impurities, organic matter, and undesirable odors. By ensuring consistent water flow and pressure, Filter Feed Pumps play a crucial role in maintaining efficient filtration processes. FILTER FEED PUMPS Filter Feed Pumps are used to draw water from the clarified water sump and pass it through the Pressure Sand Filter (PSF) and Activated Carbon Filter (ACF), which are installed in series to improve water quality. PRESSURE SAND FILTER (PSF) Working Principle: The upper layers of sand perform the actual filtration function, while gravel layers provide physical support. Specialized sand with a specific particle size is used to trap solid impurities present in...
2 comments
Read more

Precision Air Conditioners: A Reliable Cooling Solution for IT Equipment

Introduction Precision Air Conditioners (PACs) are advanced cooling systems designed specifically for environments with sensitive electronic equipment. Unlike standard air conditioners, which focus on human comfort, PACs regulate temperature and humidity within strict limits to prevent overheating and moisture-related damage. These units are essential in data centers, server rooms, and industrial facilities where stable climate control is critical for operational efficiency and equipment longevity. Precision Air Conditioners (PAC) are specialized air conditioning systems designed to monitor and control temperature and humidity within a narrow range. Unlike regular air conditioners that primarily cool people, PACs are specifically built to manage the heat generated by electronic equipment, such as servers. These devices require stable humidity levels for efficient operation, as both high and low humidity can negatively impact their performance over time. How Precision Air Conditioners W...
Post a Comment
Read more