About types of sludge dewatering / Sludge drying, Recycling drying

Sludge generated in wastewater treatment plants pass through condensation process and conditioning process, then next process is dewatering.
In dewatering process, pre dewatered sludge which have moisture content of 95% or higher is separated into solid matters and liquid, and solidified by squeezing water out. By this process, sludge in liquid state becomes cake-like state  and moisture content is lowered to 85% or less. So that post process and handling after the dewatering become easier.
This dewatering process is done by equipment called dehydrator, and there are various types for this equipment. Selection of type of the equipment is done based on condition of sludge, types of flocculant, cost, operational condition, etc. and consideration have to be done on low cost, low moisture contents of dewatered output, amount of feeding material, maintainability and so on.
At conditioning process which is pre-process of dewatering, flocculant are added and sludge is made as flocs, so that dewatering can be done efficiently. Filter clothes, sieves, centrifugal force, etc. are used and troubles such as clogging are prevented by making flocs or large particles with flocculant.
Recently, hybrid type dehydrators are made into products and they can condense and dewater sludge simultaneously.


Types of dehydrator

Filtering type

Filtering type

Filter press

Screw press

Rotary drum type

Multi-disc type

Multi-disc type screw press

Vacuum dehydrator

Centrifugal type

Centrifugal type

Condensation and dehydration

Hybrid type


dewatering waste water treatment sludge dryer kenki dryer 23/05/2020




About effects of flocculants during drying -1 / Sludge drying, Recycling drying

Comparison of drying between organic sludge and inorganic sludge after dewatering

Comparison between organic sludge and organic matter


■ Sludge drying


Water in the sludge thickened in the sludge thickener tank are removed at dehydration process to a certain degree.
However, moisture content is normally more than 80% and the sludge still has adhesiveness and stickiness. Also, latter processes are not easy because of influence of flocculants. Our drying apparatus of KENKI DRYER with international patented technology can surely dry any sticky, adhesive and viscus sludge, and also materials in liquid state like slurry, without clogging inside of the dryer. Also, because of its simple structure, its price is low and apparatus cost of the dryer can be retrieved by reducing industrial waste disposal cost within 3 years. Dried materials can be recycled as fuel, bacterial fertilizer, soil conditioner, etc. since component of the material is hardly changed because of its low-temperature drying method.
It can be applied to a system with pyrolysis apparatus as well.


Sludge drying

Self-cleaning screw



Please consider KENKI DRYER for drying of sticky materials, adhesive materials and materials in liquid state that no other dryer can deal with.
Initial, running and maintenance costs are low because of its simple structure based on internationally patented technology.
For sludge drying, costs of our dryers are estimated to be retrieved within 2, 3 years by reducing industrial waste disposal cost.
For raw material slurry drying, laborious works of manual operation will be decreased significantly by replacing box shaped compartment tray dryer with our dryer
In case of organic wastes drying, the waste can be recycled as fuel, fertilizer, soil conditioner and feedstuff after being dried.


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Pyrolyzer Biogreen
A pyrolyser with internationally patented technology which use no fire