The Process Flow Of Wastewater Sludge Treatment

What is in wastewater sludge?

sludge is the product of sewage treatment, which is an extremely complex heterogeneous BODy composed of organic debris, bacterial cells, inorganic particles, colloids, etc. Therefore, it is extremely important to properly dispose of such sludge to reduce its impact on the environment. The following is a brief introduction to the sludge treatment process to help you better understand the treatment technology and process requirements:

sludge Thickening

The first step in sludge treatment is called thickening. Thickeningis a commonly used solid-liquid separation method, which can be accomplished in two ways: the solid floats to the top of the mixed liquid, or settles to the bottom of the mixed liquid. In this step, the sludge is concentrated in a screw press dewatering machine to reduce its overall volume, thereby making the sludge easier to handle. Dissolved air flotation is another alternative method that can be used to effectively thicken sludge by using air bubbles to float solids to the top.

sludge Digestion

After all the solids have been collected from the sewage sludge, the sludge digestion process begins. The main purpose of sludge digestion is to degrade the organic solid matter in the sludge by biochemical methods, making the sludge more stable (reducing odor and spoilage), and making it easier to dehydrate, while reducing the quality of the sludge. sludge digestion generally adopts aerobic digestion or anaerobic digestion. Aerobic digestion is to aerate the sludge for a long time without adding organic matter. The microorganisms in the sludge are in the endogenous respiration stage, and are continuously reduced in the process of self-oxidative consumption. Anaerobic digestion is a sludge treatment process that utilizes facultative bacteria and anaerobic bacteria to carry out anaerobic biochemical reactions such as hydrolysis, acidification, and methane production, and hydrolyzes, liquefies and finally decomposes most of the solid organic matter in the sludge.

sludge dewatering

After recovering useful gases and other by-products, the remaining sludge is dewatered before final disposal. In most cases, sludge usually contains a large amount of water, up to 70%, although it is in a solidified state. Therefore, it is important to dry and dewater the sludge beforehand. While using a sludge drying bed is the most common way to perform this process, it is time-consuming and can take weeks to complete. To speed up these processes, screw press dehydrators are also used to perform this process. In fact, screw press dewatering machine are slowly becoming one of the best options for sludge dewatering. By dewatering the sludge, all the water can be recovered more easily and solid waste can be more easily disposed of in less time and at a lower cost. Other alternatives include rotary drum screen and horizontal screw centrifuges. sludge drying is a treatment method that uses artificial heat sources to deeply dewater sludge with industrial equipment. The disc sludge dryer is usually used to dry the dewatered sludge. The purpose of sludge drying is to greatly reduce the volume and quality of the sludge, which is convenient for transportation and disposal. The high-temperature disinfection of the sludge during the drying process can eliminate the influence of pathogens and reduce the harmfulness of the sludge. At the same time, the dried sludge particles can be used as fertilizers, soil conditioners, fuels or building materials.

sludge Disposal

When the sludge is effectively dewatered and dried, it can be buried underground in sanitary landfills or used as fertilizer, depending on its chemical composition. If the sludge is too toxic to be reused or buried, it can be incinerated.

While sewage sludge usually needs to be treated according to the relevant standards, it is more important to consider the source of the sewage, the treatment process used to reduce the sewage to sludge, and the by-products that can be recovered from the sewage. Before choosing a sludge treatment plan, the above points need to be fully considered. Not only will this help you optimize your overall output, but it will also help you reduce disposal costs through recycling prior to final disposal.

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So, if you have any ETP/STP , sludge dewatering , smell control requirement aroused, please feel free to contact Bioetp. You can find our contact on Bioetp official website www.bioetp.com.