In this method polyolephines are subjected to the cyclical "cracking" process at an increased temperature and under the presence of a selected catalyst. The products of this process are carbohydrate gases - which are burnt in burners - and fractions of carbohydrates whose boiling point lies within the range of the boiling point of petrol and diesel (light heating oil). The heavy oil fraction produced in this process is directed back to the "cracking" process and it is not the final product of this method.
Small amounts of coke are a by-product containing the catalyst and the contaminants of the processed raw material.
A "cracking" installation consists of the following parts combined together:
The decomposition takes place in one of the two mixing units M-101/M-102, which are heated up to 200°C (using hot oil or electricity). The plastic solution is transported by one of the two pumps P-101 A/B (due to the viscosity of the solution they must be cogwheel pumps) into one of the two "cracking" reactors.
There are two versions of this installation (one is shown in drawing no. 1 and in the other one the plastic materials are transported into the reactors). The products obtained in the reactors are further directed into the rectification column C-101, where the individual fractions are separated. The rectification column C-101 is a column with a powder filling (Bialecki rings from metal, 25 mm) with a side outlet. The gathering heavy oil fraction is taken up from the lower part of the column
It is normally transported by cogwheel pumps P-102 A/B into one of the two mixing units M-101/M-102 as technological oil. The excessive amount of heavy oil is directed back into the "cracking" reactors.
The vapours gathering in the upper part of the column are condensed in the water cooler E-101 and subsequently directed into the container V-101. The container V-101 functions as a separator, separating gases from the liquid condensate, and the as a reflux container. One of the two pumps P-103 A/B pumps one part of the condensate as a reflux from the container V-101 into the top of the column C-101 and the remaining part into the containers as a distillate - the petrol fraction. The diesel fraction is taken up from the "blind" bottom of the column.
|Next, it is cooled down in the water cooler E-102 (or air cooler) and transported with the pump 104 A/B into the container park.|
Temporary assumptions for determining the size of individual components of the installation: