All the rotary plates are connected to the hollow shaft by welding. Spiral heat exchangers can also be used for final effluent cooling to recover heat and, if it is to be discharged into the sea, river or stream, to protect the biology of the water body. Biological sludge is dominated by microorganisms and includes solid particles such as sediment, fiber, animal and plant residues, as well as organic matter, metal, germs, eggs and other substances that may be adsorbed. Their specific surface area and porosity are very high (porosity is often more than 99%).
the level of fibres, mainly in primary sludge, deteriorates self-granulation. A critical level of 5% is normally accepted (this level is defined as the point when wet screening (500 µm mesh) categorically rejects dewatered sludge). It should be noted that the rheology of dewatered sludge changes when stored .
Our company is authorised European distributor of Japan based Kenki Corporation, company specialised in drying equipment in Europe. The sludge from the centrifugal dryer has a fine-grained structure. The mean granulate diameter depends on the type of sludge and on the degree of drying and is approx. The mean particle size is therefore comparable to the grain distribution of unscreened sludge from other dryers.
While industrialization procedure is getting faster and faster, sludge quantity grows also very fast. Put customer at first place and provide high-quality and cost-effective products to meet customers’ different demands. Aimed at varioius projects’ requests, we can provide special and complete drying solutions. The Offered Belt Filter Press is a Combination machine of a drum thickener placed at top and a Belt Press at bottom.
In the one-stage sludge drying process, the sludge storage and drying is operated under closed negative pressure resulting in no odor. The drying process utilizes the advanced thin film sludge dryer, and recovers the heat of waste gas as well minimizes energy consumption and costs. In addition, the process is flexible, one-stage drying process can reduce moisture content to 30~45%. Four-effect condensation dehumidification drying technology is an advanced sludge drying reduction technology.
As the discs rotate, the dryer has self-cleaning effect to scrape adhered material on shafts, discs and casing off automatically. In this way,the drying performance is enhanced by the prevention of adhesion of material and the renewal of the heat transfer area. This machine can make the materials at outlet presented as small particles or powder which provides convenience for next process.
The energy consumed during the process is the electricity for the input to compressor, fan, and motor. The product adopts a belt type of closed cabinet dehumidification heat pump drying. There is no need for additional energy (steam, thermal-conduction oil and hot-blast air), as well as no need for treatment system for tail gas. This Sludge drying machine can dry many kinds of materials which contain moisture, such as coal, coal slurry, slag, industrial waste, and clay stone. This system is using the humidification mechanism of low-temperature heat pump, the sludge cake on the net strip is dehydrated and decremented by way of convective hot air drying. Where the whole system is designed fully closed, and the drying hot air is free from thermal loss.
With a large heating area per unit effective volume, the material is quickly heated to sterilization temperature, which avoids heating for a long time and changing the quality of the material. To sum up, the comprehensive utilization of sludge resources will accelerate the sustainable development of economy. As an important part of the disposal process, the sludge drying technology is relatively mature, which can achieve mass, continuous, fully closed and other operations.
Drying can stabilize the sludge, thus reducing the putrid smell and improving the disinfection effect.
The dry sludge is transported to a thermal power plant for power production. Meanwhile, the heat required for drying is the waste steam from the thermal power plant. The superiority of this application lies in the full use of social resources and social division of labor to solve sludge problem. It forms a complete market-oriented and sustainable development business application.
There are branches and reticular structures similar to villi in appearance. If not properly treated, arbitrary emissions will cause secondary pollution. • Sludge is introduced onto the drying bed by gravity flow at a rate of 9.4 L/s and to a depth of 300 to 750 mm (12 to 30 in.).
The filter main part is formed by a screw axis with fixing and moving plates overlapping. It dewaters adequately by the gravity and the power from back pressure plate during the process. The filtrate water comes out from the space between fixing and moving plates. For the Disc Type Sludge Dryerdeveloped by VAPORUN, the material is fed into the dryer from the feeding port, and the working medium flows between the shell and the hollow shaft. Through the jacket, hollow shaft and hollow disc welded on the shaft to transfer heat, the material is indirectly heated and dried, resulting in the accumulation of water vapor in the dome on the top of dryer.
The special wedge-type stirring heat transfer blades in the equipment have high heat transfer efficiency and self-cleaning function of the heat transfer surface. On-site thickening and dewatering of sludge is a fundamental part of all current wastewater treatment options to significantly reduce the sludge volume. This has a huge impact on costs for transportation, effluent disposal, storage and drying. It is also highly relevant for sludge to be used as digester feed for biogas production, thermal processes and composting. To meet every need, Alfa Laval offers a complete spectrum of robust, well-proven technologies that effectively separate off the liquid phases and achieve a high level of dry solids content. Sludge dryer can dry 90% moisture content to finished product at one time.
Because of low-temperature drying, the composition of the dried material is not affected and organic sludge can be sold as fuel, fertilizer, etc. after being dried. Because fresh air from outside is kept off, the temperature inside of the dryer is kept high, amount of moisture in the exhaust air discharging water is small, and the discharged water can be returned to wastewater treatment facilities. Sludge Dryersmanufactured byMet-Chemare designed for small, medium and large quantity sludge generators. These dryers can fit under the filter press for direct loading or can be located elsewhere in the plant. The sludge is dried by the heated liner of our unit while it is broken-up and circulated by our spiral blade system.