Eggersmann Plant Engineering
Compost Fine Processing
Our process enables the specific removal of films and plastics that cannot be separated using conventional screening technology.
Biowaste is increasingly contaminated with foreign matter such as glass, metals or plastics. The plastic content in particular is increasingly causing problems for plant operators. Especially difficult: either the compost is contaminated with impurities because the screen cut is too coarse or the screen residue, which is particularly expensive to dispose of, contains a lot of compost because the screen cut is too fine. As operators of our own composting plants, we have developed a system solution for this. It consists of our star screen technology and the CO2MPOSTCLEANER. The screen residue to be disposed of can thus be reduced to less than 7 % of the total mass.
STAR SELECT Star Screens
Star screens are ideal for processing compost. The interchangeable screen shafts make it easy to pre-define the end product using different screen star sizes and spacings. Our patented SplitSpeed system ensures an even distribution of the material on the screen deck by means of different speeds of the screen shafts – this guarantees optimum screening results. The individual fractions can be freed from impurities on the discharge belt using the AIRFIX air separator. The centre fraction is then cleaned of film and plastic and fed back into the composting process. Depending on requirements, we offer both mobile STAR SELECT and stationary BRT HARTNER STS star screens. The fine fraction is transferred into the CO2MPOSTCLEANER.
Eggersmann CO2MPOSTCLEANER
The CO2MPOSTCLEANER is a arch belt separator specially designed for fine processing. It makes optimum use of the different falling and sinking behaviors as well as the different ballistic properties. The machine consists of three sections:
Drop Chute With Arch Belt
The compost is fed into the machine via an acceleration conveyor. On impact with the arch belt [1], the particularly heavy components are slowed down by the force of their own mass and channelled into a chute [2]. Light and medium-weight parts are passed on to the separating chamber via the arched belt. Supply air pushes lighter materials upwards.
Separation Chamber
Light films and plastics that have already been whirled up by the supply air are extracted directly upwards after entering the separation chamber [3]. The compost diverted via the arch belt hits a separation point [4]. The fine and medium-heavy fractions are now separated. The latter falls down again due to the impact and is discharged via a conveyor belt [5]. The fine fraction is passed on to the next chamber by another conveyor belt [6]. During this second impact in the separation chamber, the material is further blown under so that light particles can be sucked upwards again [7].
Drop Chute
The last chamber is a drop chute. The fine fraction of the compost slides downwards [8], where it is again blown under. The foreign matter particles that now float to the top are sucked out again from above [9].
The extracted material from all three light material separation points is divided itself into foils in a light fraction separator. The pre-cleaned air, interspersed with fine compost, is channelled into a bag filter. Some of the cleaned air is then fed back into the process. The highly efficient Eggersmann exhaust air treatment ensures the lowest residual dust content < 5 mg/m³, which is why the remaining air can be released back into the environment without any problems. The separated fine compost is added to the cleaned compost via ascending screws.