Contact aeration method ・Biofilm processes / Sludge drying, Recycling drying

This article is about contact aeration method which is one of three types of biofilm processes of various activated sludge method in wastewater treatment.

■ About Contact aeration method


Contact aeration method is a method to treat wastewater by microorganisms attached on surface of carriers (contact materials, filer materials) filled in reaction tanks.
Oxygen used for growth of microorganisms is supplied and aerated by aeration apparatus. Microorganisms grew too much are peeled off spontaneously and settled at settling tank, however, there is no sludge to be returned and disposed as waste sludge. Objects which have large surface area and enough air gaps is suitable for the carriers (contact materials, filer materials) and there are several types of shape which are tube type, string type, net type, flat board type, round type and so on. Also, polyethylene, plastic, etc. are used for their materials.
Since, not like activated sludge process, there is no returning sludge in this method, maintenance is easy and processing is stable. This method is often used in small wastewater treatment plants. However, biofilm sometimes grows too much and carriers are clogged in case that work load is too high. Concentration of wastewater is decided based on amount to microorganisms attached on carrier and it has a limit.

contact aeration method wastewater treatment sludge dryer kenki dryer 24/05/2020



Types of waste water treatment / sludge drying, slurry drying, waste drying


■ 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



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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