It is only the biological material that is to be entered into the biogas installation (to produce bio pulp). Therefore, various steps must be taken to make a “clean” bio pulp from the mix of waste.
When the waste enters the energy plant it goes into a process that mainly consists of two steps. Each process has two kinds of materials exiting:
Step 1: Separation equipment
It is a kind of Hammer mill, which separates the waste into:
a)The main part of the biological material is separated and then goes directly into the biogas tank.
b)The leftover material –so-called reject –consists of mainly plastic but can also contain other materials. This reject has a lot of liquid in it, and there is still a great quantity of biological material tangled in the packaging.
Step 2: RUNI Screw press
This reject is both difficult and expensive to dispose of, as it is wet plastic,it is not very suitable for combustion nor recycling, and besides from this fact –it still contains bio pulp curled op in the plastic packaging.
With the RUNI Screw compactor after the separator, the plastic reject is squeezed, and it is possible to introduce extra percentages of bio pulp into the biogas tank, and as a bonus, the reject is now dry enough to be sent to incineration, with a lot less kilos than before, and therefore a great reduction in transport costs.
The conditions at the biogas plants are very demanding. The plants are working 24 hours all year round, and the waste material often contains abrasive elements like sand and at times “surprises” like for example large pieces of metal, which the RUNI have been able to handle. The RUNI handles these great demands very well.
The screw compactor for separating liquids from food waste reject can handle op to 5.000 kg/hour depending on the material and achieves up to 65% of dry matter with only a 15 kW motor.
This is a very energy-efficient way to separate liquids from packaging and rejects. The automatic start and stop function and the automatic hydraulic jaws make sure the operation of the RUNI is easy and very little time-consuming.
There are many examples, where the company that handles the food waste has a hammermill or another kind of separator to separate the plastic reject from the organic food waste and then in the next step has a RUNI for dewatering this plastic reject and by this having a great economic gain, both in reduced costs to dispose of this reject and in gained extra % of bio pulp squeezed out of the reject.
RUNI has more than 80 machines for dewatering foodwaste reject worldwide and always manages to be an economic asset for the waste handler