Effectively dewatering wastewater sludge has traditionally involved belt presses, rotary fan presses, screw presses and centrifuge. However, these technologies can only remove water to a limited extent.
The ELODE sludge dewatering system is an effective solution that separates solid and liquid components for easier disposal. Its compact design installs easily into a facility’s dewatering process. Compared to thermal drying, ELODE sludge dewatering equipment is more cost-effective and energy-efficient.
Understanding the ELODE Sludge Dewatering System
Sludge dewatering is the process of minimizing waste by weight and volume in preparation for effective disposal. Sludge is a semi-solid slurry byproduct of many municipal and industrial procedures.
Sludge dewatering centrifuges and presses usually yield about 15-23% solids. Thermal dryers can get that number up to 40%, but they come with high equipment costs and a large footprint. There are few technologies that can achieve between 23% and 60% solids and thus offer better water removal at a reasonable price range.
The ELODE sludge dewatering system was developed to meet this need. It enhances existing systems that produce dewatered products called cakes. The ELODE system flattens sludge cakes onto a belt and applies a direct current that rearranges the molecules in the material to release the water. The water drains from the belt into a sump and returns to the facility’s headworks.
In just two to three minutes, the ELODE system can double solid content. For example, if you are currently operating at 15% solids, our system can raise that level to 30% or even more. The ELODE dewatering process also takes up less floor space and can be retrofitted to most existing equipment.
How Does ELODE Save Money and Energy?
Eradicating sludge residue can be expensive when using conventional thermal drying methods. Because the ELODE system uses an electrical field instead of boiling away excess water, it saves significant energy and operating costs. Although the technology does produce some heat, it is far less than that produced by thermal dryers. ELODE uses about 120 kilowatts per ton of wet cake, which is more than mechanical dewatering but far less than thermal drying.
Shortly after investing in ELODE equipment, you will see a quick payback. This especially applies if you operate for large urban areas that pay higher rates for landfilling. For example, if it currently costs you $60 per wet ton to landfill solids, the ELODE system can help you cut your costs in half.
Try ELODE’s Innovative Dewatering Technology
While mechanical presses and centrifuges offer limited dewatering capabilities, thermal dryers consume enormous amounts of energy to dewater sludge. ELODE presents a balanced solution. Unlike thermal drying, our electro-osmosis dehydrator can save money and energy while effectively boosting solids content.
Whether you process food wastewater or municipal wastewater, Elode USA Inc’s dewatering systems can help you dewater sludge while cutting transportation, disposal, and storage costs. Contact Elode USA Inc for more details about our sludge dewatering system.
Raw, untreated sewage is a serious hazard to the environment as well as to the nearby population. However, through proper treatment, wastewater facilities can keep up with demand, reduce pathogenic risks, and reintroduce clean water back into the environment. Learn more about the role of sludge treatment in improving wastewater processing.
When municipal wastewater treatment centers process wastewater, they generate sewage sludge as an unwanted byproduct. This semi-solid sludge is made up of chemicals, plant nutrients, organic material, and inorganic waste. This material is also full of bacteria and pathogens, making it dangerous to process and store without the right tools and procedures in place. Treatment is one of the most important parts of wastewater processing, as it alters the sewage sludge to minimize environmental hazards as well as safety and health concerns.
Sludge Treatment Process
The sludge treatment process incorporates these four stages:
1. Sludge Thickening
One way to help control sewage sludge is to thicken it. This can help control the flow of semi-solid fluid, reduce its overall volume, and make the material easier to process.
Before sludge thickening occurs, many systems add clarifying agents and mix them into the fluid. After reaching primary or secondary clarifiers, the sludge is then stirred to help the material settle and thicken. A gravity thickener reduces the final volume of the material. In the primary stage, the sludge is between 8 and 10 percent solids. Secondary sludge can contain up to 4 percent solids after thickening.
2. Sludge Digestion
Now that the sludge is more compact and easier to handle, wastewater treatment plants can start to address the pathogens and bacterial hazards in the sludge. Sludge digestion processes break down the material so it decomposes and turns into stable components. The dangerous pathogens are digested, and the lingering solids lose mass. After this stage, treatment facilities can dewater the sludge without worrying that pathogens will adversely affect the environment.
Let’s take a closer look at the sludge digestion process, which usually involves two stages:
- Heating and Mixing: The sludge is mixed in a closed tank to break down the material. It is also heated to encourage the growth and activity of bacteria that anaerobically eat the pathogens in the sludge. Certain acid-forming bacteria can consume the lipids and proteins in organic waste to produce water-soluble, less hazardous byproducts. Those byproducts, in turn, become fatty acids.
- Gas Production: Treatment facilities move the sludge into a second tank, where aerobic digestion takes place. Gases start to separate from the sludge as more bacteria break down the sludge. While the resulting CO2 is often a waste product, the facility can collect the methane to provide power for the digestion tank and other functions.
Once the treatment process has collected the methane for power applications, the sludge can move to the dewatering stage, which separates salvageable water from the material. Up to 85% of the volume of sludge can be water. When facilities dry and dewater the sludge, they can both safely reintroduce water to the environment and significantly reduce the total volume of remaining waste.
Next, the sludge passes through a centrifuge, which uses centrifugal forces to press the water out of the sludge and isolate the dried, solid remainder of the sludge for disposal. Some treatment facilities use a filter press instead to press all the water out of the sludge and compress the remaining solids.
Two of the most common processes for drying sludge are depositing the material along sludge-drying beds and processing the sludge in solid-liquid separators (thermal dryers).
Now that water has been removed from the sludge, the remaining cake can be disposed of through:
- Incineration and coverage
- Use as a fertilizer (depending on the makeup of the sludge)
Benefits of Wastewater Treatment
Proper wastewater treatment has several benefits, ranging from easier and safer waste disposal to the formation of useful byproducts. Consider these crucial benefits:
By treating and releasing water from sewage sludge, facilities significantly reduce the total volume of remaining waste. This reduces adverse environmental effects and also reduces the total disposal cost of sewage sludge cake.
By collecting methane, facilities can power the digestion tanks and other processes in their treatment stations. This lowers the total energy consumption and can even make some wastewater treatment processes self-sustainable. In the event that the sewage sludge produces excess methane and generates extra electricity, that power can be sold to the regional or national grid.
Safe, biodegradable material in dried sewage sludge can be used as a fertilizer, increasing agricultural production and decreasing sewage storage demand.
Contact ELODE for the Right Sludge Treatment Process
By investing in wastewater processing that includes sludge treatment processes, you can reduce negative environmental effects, increase energy efficiency, support sustainable processes, and more. Wastewater processing produces positive short-term and long-term effects that help combat water shortages and other crises around the world. Contact our team today to learn more about how ELODE is developing and innovating sludge treatment processes.