There are many benefits to using mechanical dewatering equipment for industrial wastewater treatment. These dewatering devices can improve efficiency, cut costs, and help your business run more smoothly.
Most dewatering methods involve settling water from solid waste or sludge in a pond.
Dewatering can be a cost-effective way to reduce the volume of wastewater sludge, making it easier to transport or dispose of. The most efficient wastewater treatment solution can also help save energy in post-treatment processing (drying and incineration).
Several studies have analyzed the economics of mechanical dewatering for industrial wastewater treatment. These studies usually use data from existing wastewater plants to derive cost functions for different treatment steps.
The most common methods used for mechanical dewatering include belt presses and filter presses. Both are effective for a wide variety of industrial and municipal sludges and can be used to decrease the volume of sludge.
Filter presses are a proven dewatering method that doesn’t require these chemicals or the need for a high amount of labor hours.
Dewatering industrial wastewater treatment can be an essential step in the overall process of achieving effective water recycling. This step removes excess water from a solids slurry (sludge or cake) to reduce volume and generate a non-fluid consistency for final disposal or reuse.
In a conventional mechanically dewatered sewage treatment plant, the influent wastewater is typically treated by settling or flotation, followed by sludge dewatering to remove excess water from the solids slurry. This method results in dense and compact sludge that can be landfilled or disposed of in landfills.
The advantages of chemically dewatering wastewater sludge include reduced capital and operating costs for disposal. In addition, chemicals can remove heavy metals and other nonbiodegradable pollutants from the sludge resulting in an environmentally friendly product for removal.
The optimum chemically dewatering wastewater system will employ a slurry to a solids concentration of 1 to 3% solids by weight before it is chemically separated in equipment screens, sand filters, or drain bags. The separated solids are then landfilled, gasified for energy generation, or sold as a nutrient-rich fertilizer.
Mechanical dewatering (also referred to as filtering or filtration) is the process of separating liquid wastewater residuals into a solid or “cake” and a liquid part, usually using belt filters, centrifuges, or chamber filter presses. These processes often require adding chemical coagulants or flocculants to improve their efficiency.
Sludge dewatering is an essential pre-treatment method for wastewater to be transported, composted, incinerated, or disposed of in landfills. It reduces the amount of sludge in a batch, making it easier to transport and handle.
The belt press is the primary mechanical sludge dewatering device used in wastewater treatment plants. It works by applying a gradually increasing pressure to the slurry between opposing belts held in place by a series of rollers. This squeezing and shearing action causes the slurry to thicken, making it more difficult for free water to flow through and, thus, concentrate suspended solids. These machines almost always require the addition of chemicals to facilitate their operation and can be expensive to operate, maintain, and repair.
Dewatering of sludge is the main objective for many industrial and municipal wastewater treatment plants. It is a cost-effective volume reduction method and sludge management, producing dry, high-solid cakes for transportation, storage, or disposal.
Typical dewatering methods for industrial wastewater include gravity thickening, filter presses, and dissolved air flotation. The type of dewatering method used will depend on the amount of sludge generated and the quality of the effluent produced.
Belt presses are a standard mechanical dewatering method employing gravity drainage and pressure to dewater sludge. They work by gradually squeezing the sludge between opposing belts held in place by rollers.