SE510929C2 - fuel pellets - Google Patents

Abstract

A fuel pellet, which is made of compressed material particles, consists of 30-50% by weight of plastic, 25-35% by weight of cardboard and 25-35% by weight of sawdust.

Description

The fuel pellet preferably contains at most 50% by weight of plastic, at most 35% by weight of cardboard and at most 35% by weight of sawdust.

In a preferred embodiment, the fuel pellet consists of 30% by weight of plastic, 35% by weight of cardboard and 35% by weight of sawdust.

Five different types of pellets have been produced from torn and / or chopped winning material, which has been crushed, to form material particles, which are then compressed in a known manner into pellets. In this case, combustible plastic from plastic material recycling plants (but not PVC and Teflon), such plastic-coated cardboard used in milk packaging and the like, as well as dry sawdust from carpentry factories, especially parquet floor manufacturers, have been utilized.

These five different pellets, which are referred to here as samples 1, 2, 3, 4 and 5, had the composition given in Table 1.

Table 1 Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sawdust (% by weight) 90 0 40 30 35 Plastic (weight%) 10 0 10 15 30 Cardboard (weight%) 0 100 50 55 35 As can be seen, sample 1 contained 90% by weight sawdust and 10% by weight of plastic. Sample 1 thus largely corresponds to the initially known, known sawdust pellet. Sample 2 corresponds to the initially known, known carton pellet.

As further shown in Table 1, sample 3 contained 40% by weight of sawdust, 10% by weight of plastic and 50% by weight of cardboard and sample 4 30% by weight of sawdust, 15% by weight of plastic and 55% by weight of cardboard. As also seen, Sample 5, which corresponds to a preferred embodiment of a pellet according to the present invention, contained 35% by weight of sawdust, 30% by weight of plastic and 35% by weight of cardboard. 10 15 20 25 3 510 929 The properties of the five samples in terms of calorific value, ash, crumb and moisture repellency have been investigated. Values obtained are given in Table 2.

Table 2 Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sawdust (weight%) 90 O 40 30 35 Plastic (weight%) 10 0 10 15 30 Cardboard (weight%) 0 100 50 55 35 Calorific value (MJ / kg) 18, 43 18.88 17.97 17.96 19.08 Ash (weight%) 0.50 9.20 4.80 4.70 2.80 Crumble (1-5) 2 5 3 4 5 Moisture rejection (1-5) 1 2 3 3 5 The samples have been examined for calorific value and ash by the Swedish Testing and Research Institute (SP) in Borås, whereby method SP 0492 (= ISO 1928) and SP 0502 (mod. SS 18 71 71) the calorific value is the effective calorific value at constant utilization. print. Crumble and moisture rejection have only been estimated subjectively and ocularly and are given in scale 1-5, where 5 corresponds to good values, ie small crumb and good moisture rejection, and 1 corresponds to bad values, ie heavy crumb and low moisture rejection. properties, of the known pellets (samples 1 and 2) as described in the introduction, are clearly shown in Table 2.

It is further clear from Table 2 that sample 5, which is moisture, corresponds to a pellet which does not crumble, rejects, which has a high calorific value and which gives a small amount of ash.

If, based on the composition of the sample 5 (35% by weight, 30% by weight of plastic and 35% by weight of cardboard), sawdust is increased, the content of sawdust increases, the properties in terms of crumbling and moisture repellency deteriorate, but the amount of ash is reduced. If the content of sawdust is reduced, the opposite result is obtained, at the same time as the calorific value increases if the sawdust was replaced with plastic but decreases if the sawdust was replaced with cardboard.

If the plastic content is reduced from 30% by weight, only a negative change in the properties of the pellet appears to be obtained in that the crumb and moisture repellency deteriorate, the ash content increases and the calorific value decreases. If the plastic content is increased, the opposite changes are obtained. However, it should be noted here that the calorific value of the properties. with an increase in the plastic content can become so high, existing ovens can not cope with the heat generation that takes place without being destroyed.

If the carton content is increased from 35% by weight and this is done at the expense of the plastic content, all four properties discussed above deteriorate, while a reduction in favor of the plastic content has the opposite effect. If, on the other hand, the carton content is increased at the expense of the sawdust content, the amount of ash increases and the calorific value decreases. the properties of crumbling are improved, while a reduction of the carton content in favor of the sawdust content has the opposite effect.

Taking into account the above, it has been found that the pellet suitably contains 25-35% by weight of saw- 30-50% by weight of plastic and 25-35% by weight of cardboard.

SP has also analyzed the five samples with regard to shavings, on the content of other substances. These analyzes are summarized for some of these substances in Table 3.

Table 3 Substance Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sulfur (wt%) 0.01 0,06 0.05 0,06 0,06 Chlorine (wt%) 0.01 0,06 0,05 0,04 0.02 Cadmium (mg / kg) 0.11 <0.05 0.18 0.34 0.09 Manganese (mg / kg) 84.50 22.50 65.50 59.00 39.50 Zinc (mg / kg) kg) 9.90 24.00 37.00 34.00 20.50 5 510 929 It should be noted that in determining the above intervals for the components included in the pellet, of course, the impact of the components on the content of sulfur, chlorine, cadmium, manganese and zinc, as this content is shown in Table 3.

Claims (2)

Pans 9703655-2 510 929 6 PATENT REQUIREMENTS 1. The fuel pellet, which is made of compressed material particles, is characterized in that it consists of 30-50% by weight of plastic, 25-35% by weight of cardboard and 25-35% by weight of sawdust. 2. The fuel pellet according to claim 1, characterized in that it consists of 30% by weight of plastic, 35% by weight of cardboard and 35% by weight of sawdust. 10