Tips for Wastewater Treatment Plant Operators
By: Tom Frankel
Post Date: June 29th 2023
Tips for Wastewater Treatment Plant Operators
Operating a wastewater treatment plant comes with many critical responsibilities. Between executing multiple water treatment steps, maintaining equipment, preparing for hazards and emergencies, and meeting permit specifications to avoid legal penalties, wastewater operators do a lot to keep plants functioning and protect workers.
This guide explores the different duties of water treatment operators and some key tips for those who may be new to water treatment operations.
What Are the 5 Steps of Wastewater Treatment?
How do wastewater treatment plants work? Here are the typical stages of water treatment plant operation:
1. Bar Screening
A bar screen is a large, coarse screen that filters out debris from the wastewater, such as plastics, wood, rags, paper, metals, grease, leaves and twigs. In addition to removing solids from the water, bar screening helps prevent damage to the plant’s valves, pumps and other equipment.
After the wastewater passes through the bar screening equipment, plant workers wash, press and dispose of the materials in a landfill.
2. Grit Removal
During this stage, operators remove fine grit like sand and gravel by moving the wastewater through a grit chamber. Just like larger debris, fine grit must be eliminated to prevent pump and equipment damage. Because it’s too small for a bar screen, the grit must be removed through a grit chamber.
There are multiple types of grit chambers, including aerated, horizontal-flow and vortex. Each type allows heavy grit particles to fall to the bottom of the chamber, while lighter organic particles remain suspended. Plant workers then physically remove the grit from the bottom of the chamber, then dispose of the material in a landfill.
3. Primary Clarifier
Wastewater operators remove primary sludge — material that settles at a slower rate than grit — using large circular tanks called clarifiers. They pump primary sludge off the bottom. Then, the wastewater exits the tank from the top.
They skim any floating debris, like grease, off the top. They may also add chemicals to remove phosphorus. After the water is removed, the sludge is discarded and often used as fertilizer.
During aeration, plant workers pump air into a large tank, encouraging the conversion of ammonia to nitrate so beneficial bacteria can grow and break down organic material. This process is called nitrification.
After nitrification occurs, the microorganisms remove oxygen molecules from the nitrate molecules, consuming pollutants into nitrogen, cell tissue and water. The nitrogen is released as nitrogen gas.
Operators pump the treated wastewater into a secondary clarifier, allowing any remaining organic sediment to precipitate out. They then add chlorine to kill any remaining bacteria in the chamber.
Once the wastewater has been tested for proper pH, ammonia, nitrate, residual chlorine and dissolved oxygen levels, they can release the treated water — or effluent — back into the environment.
Main Stages of Cleaning Wastewater
What are the three main stages that local wastewater treatment plants may use to clean wastewater? While the five steps above outline the primary stages of operating a wastewater treatment plant, they can be further condensed into three main phases:
- Pretreatment: Wastewater flows into the treatment tank, allowing bar screens and grit chambers to remove large solids and fine grit.
- Primary treatment: The pretreated wastewater moves into primary clarifiers, allowing further impurities to settle out.
- Secondary treatment: During secondary wastewater treatment, beneficial microorganisms help break down solid materials.
Some plants may implement a fourth stage — tertiary treatment — for an additional layer of disinfection and filtration. However, tertiary treatment is usually optional and used for particularly stringent effluent requirements.
4 Tips for Wastewater Operators
Here are some essential tips that wastewater treatment plant operators should follow.
1. Use Personal Protective Equipment (PPE)
Wastewater is ridden with contaminants, making PPE a must when handling it. To prevent contact with wastewater, operators should wear:
- Splash-proof face shields or masks.
- Rubber gloves.
- Liquid-repellant coveralls or aprons.
- Hard hats.
2. Know How to Identify and Address Potential Problems
As plant operators collect samples, log readings and conduct various wastewater treatment stages, they should closely observe everything in the facility. They should know how to pinpoint subtle changes that indicate a possible issue, such as an odd color or odor in return sludge, a dripping mechanical seal on a pump or an electrical fault. These signs warrant action from an experienced wastewater operator.
3. Practice Proper Equipment Cleaning and Maintenance
It’s important to get a jump on maintenance before minor, inexpensive problems turn into large, costly repairs. Regularly cleaning and maintaining wastewater treatment systems can extend equipment life span, increase aeration efficiency, decrease energy consumption and costs and optimize plant performance.
Proper water treatment system maintenance should include:
- Checking for signs of equipment aging and replacing components as necessary.
- Monitoring air volume, solid levels, bubble patterns, blower discharge pressure and equipment performance.
- Draining tanks regularly.
- Installing FEPDM™, PFTE or Viton® membranes to reduce fouling, scaling and cleaning frequency.
- Avoiding over-aeration to prevent energy wastage and negative equipment performance.
- Instructing employees on proper cleaning and maintenance procedures.
4. Prepare for Emergencies
Every wastewater treatment facility should incorporate emergency planning protocols for potential hazards. These protocols should include:
- Backup power sources: Plants should have standby power sources — such as portable and fixed-in-place generators — that can run all critical equipment. Operators should test all standby power sources and transfer switches monthly. Additionally, there should be a sufficient fuel supply for 10 to 14 days.
- Hazardous material inventory: Wastewater treatment plant operators should take inventory of potentially hazardous materials and chemicals. They should pay special attention to chlorine equipment and storage areas, as this material is toxic and has corrosive properties. Plant managers should develop safety protocols in case of a hazardous release, including a list of emergency contacts, such as the local fire department.
- Staff training: All plant workers should know emergency protocols and responsibilities. They should also be trained in the Incident Command System and National Incident Management System in case an emergency situation warrants their intervention. Managers should conduct periodic training exercises, as well.
- Flood-prone area identification: Wastewater operators should create a list of flood-risk areas, including pump wells, manholes and open tanks. In addition to special equipment for flooded areas, facilities should have sandbags readily available for minor flooding.
Choose SSI for All Your Wastewater Needs
One of the best practices for wastewater treatment plant operators is having high-quality equipment to assist every process. SSI Aeration, Inc. designs and manufactures advanced solutions for wastewater and sewage treatment facilities.
SSI has everything from aeration systems to bubble diffusers and membranes. Catering to a wide variety of industries, SSI tailors its products to common processes like moving bed biofilm reactor and integrated fixed-film activated sludge.
Find reliable wastewater treatment solutions for your plant’s unique needs. Contact SSI Aeration for more information about available products and equipment.
Mr. Frankel co-founded SSI in 1995 with experience in design and distribution of engineered systems. He is in charge of sales, marketing and operations in the company. Mr. Frankel holds multiple US patents related to diffusers. He is a graduate of Washington University in St. Louis.