As snow melts, heavy spring rains hit, and winds pick up, a lot of trash and debris ends up in the nation’s waterways. In Oregon, the Willamette River’s trash has become a major concern.
The organization Willamette Riverkeeper takes out as much as 432 yards of trash annually. Efforts have been heightened to get the state and municipalities to create better programs making it easier for visitors, residents, and the area’s homeless to dispose of trash properly.
This isn’t the only place dealing with excessive amounts of trash. Volunteers in Illinois, Iowa, Louisiana, Mississippi, and Missouri recorded the amount of trash they were pulling from the Mississippi River. Of the items they logged, plastic accounted for 75% of the trash. The remaining percentages were:
- Paper and wood – 9%
- Metal – 7%
- Glass – 5%
- PPE/Masks – 2%
The most common items found in the river were:
- Cigarette butts
- Food wrappers
- Beverage containers
- Foam and Styrofoam fragments
- Hard plastic pieces
- Paper/cardboard
- Plastic bags
- Tin/aluminum cans
- Plastic cups
Keeping these items out of the rivers, lakes, streams, and oceans is vital. It’s a key reason why municipalities need to look at the benefits of screening systems in waterways.
What Screens Do
Screens are used in water treatment, wastewater treatment, and hydropower plants. As wastewater or river/lake/ocean water enters a plant, it passes through screens that capture objects. Screens can capture dead animals, branches and logs, trash, leaves, and other larger particles.
If those items entered into the process of treating and cleaning water, it could lead to equipment damage, faster wear and tear on motors and pumps, and clogs. Plants pay less for repairs and replacement parts, which saves money over time.
There are different types of screens, but the process is always similar. They have mesh screens that capture items. Then, trash rakes or rake teeth pull them from the screen and move them to bins for composting or a landfill.
Some facilities use incinerators, which use waste-to-energy to help generate power used by the plant. This makes it possible for the next stages of water treatment, such as sludge removal, to take place.
Explore the Different Types of Screens
What are the different options when it comes to screens? We recommend Raptor® equipment. These are the options to consider.
Raptor® Complete Plant
If you want a plant that can screen solids and waste materials and remove grit in one, the Raptor® Complete Plant is the system for you. Add a manual or automated grease trap, too. It handles flow rates of up to 4 million gallons per day.
The components are pre-assembled, which makes it easy to install the entire system and have it up and running in little time. It also costs less than a designed system as it’s pre-engineered.
Raptor® FalconRake® Bar Screen
This heavy-duty bar screen is ideal for high use with high removal loads in water treatment plants, septage pump systems, and combined sewer systems. The link system can lift half a ton without a problem. Rakes grab materials from the bottom of a channel and raise them upwards to the top where solids are removed into containers for further processing.
The construction is corrosion-resistant, and there are no bearings, bushings, guides, or sprockets in the lower areas of the equipment, which ensures the drive system is fully above water. This makes maintenance simple. This design also helps prevent jams.
Raptor® Fine Screen
A Fine Screen system is ideal for removing troublesome solids like fats, oil, and grease. Varied screen bars sit in the bottom of a tank and have a rotating rake that continually cleans the cylindrical screens when the water level reaches a specific point.
Debris is disposed of in a bin after being compacted and dewatered thanks to the help of a screw conveyor. It’s possible to get a weather protection system that protects it from as cold as -13ºF.
Raptor® Micro Strainer
The Micro Strainer is a good choice for small treatment facilities. A cylindrical basket fits in a lower chamber and spins while screening out solids and debris. Those solids move up a tube with the help of a screw conveyor. They’re compacted and dewatered before moving to a container for composting, trash, or incineration.
There’s a single drive, which helps keep maintenance requirements to a minimum. The Micro Strainer is often used in submersible pump stations and manholes. It’s also a good choice for industrial plants that pre-treat wastewater before it moves on to the sewer system.
Raptor® Multi-Rake Bar Screen
This multi-rake bar screen is positioned within a tank with screen bars (think of ladder rungs) that go up from the floor to the top. They pick up solids as the screen bars rise, and those items are deposited out of the bar screen when it reaches the top of the tank with the help of rakes. Rakes scrape all items off the bar before that bar lowers back down.
A chain guide ensures constant motion at the desired speed. The entire multi-rake bar screen is corrosion-resistant due to the stainless-steel construction. If there’s a jam, the system automatically reverses to clear it. Rakes clean the bar screens as they go and can be replaced as needed. As an added benefit, it’s possible to get this system on a hinged system to make it easy to swing out of the channel when maintenance is necessary.
Raptor® Rotary Strainer Screen
With the Rotary Strainer Screen, water comes into the self-contained tank where a horizontal cylinder of heavy-duty wire awaits. The openings of that wire range from 0.01 to 0.1 inches and a spray bar and blade assembly with automatic cleaning. Water passes through the mesh and solids are captured on the wire mesh and are then cleared of solids.
The solids pass through a discharge chute into a bin for composting or whatever your plant does. Everything is above ground, which makes maintenance easy to manage. The rotary strainer screen is used in multiple settings, including pre-treatment measures in wineries and food processing plants and fine screening in wastewater treatment plants.
Raptor® Rotating Drum Screen
The removal of small particles is completed with ease with the Rotating Drum Screen. It’s very efficient and has a high removal rate, which meets the requirements of Membrane Biological Reactors. You can get a wedge wire basket or perforated plate with openings of 0.2 to 0.25 inches.
As the waste and materials are screened out, it’s dewatered and compacted, reducing volume by half. It reduces the waste’s weight by as much as 67%, so the cost of landfill disposal is less. It has a single drive and stainless steel construction for long life and minimal maintenance.
Raptor® Septage Acceptance Plant
If your plant accepts septage hauled in from residential homes and businesses, the Septage Acceptance Plant screens, dewaters, and compacts the solids. The septage is pumped out of trucks and into a system with cylindrical screen bars. Rakes scrape the bars to prevent clogs.
It’s a stainless-steel design that resists corrosion, and it works faster so haulers can unload quickly. You can add a second inlet so that two trucks can unload at the same time.
Raptor® Septage Complete Plant
While there’s the Septage Acceptance Plant, there’s also the Raptor® Septage Complete Plant, which is automated and completes screening and grit removal at the same time. Everything is pre-assembled for fast, hassle-free installation.
Work With Lakeside Equipment
Lakeside Equipment is here to help you explore the best options for your water cleaning goals and budget. Whether you’re starting out or need to completely upgrade your older screens with more efficient options, we have the solution you need.
