ES2592806B1 - PROCEDURE FOR THE VALUATION OF VEGETABLE REMAINS MIXED WITH RAFFY OF POLYOLEFINS FROM HORTICULTURAL CROPS - Google Patents

Abstract

Procedure for the valuation of plant residues mixed with polyolefins raffia from horticultural crops. # The present invention relates to a process for obtaining polymeric raw materials for industrial application, from plant residues mixed with polyolefins raffia from horticultural crops. , mostly from agricultural greenhouses, subjected to fermentation. The products obtained according to this invention are widely implanted from a commercial point of view. # Vegetables mixed with raffia are subjected to aerobic fermentation to convert them into compost, separating said compost from the unfermented part, and obtaining polymeric raw materials for industrial application .

Description

5

10

fifteen

twenty

25

30

PROCEDURE FOR THE VALUATION OF VEGETABLE REMAINS MIXED WITH RAFFY OF POLYOLEFINS FROM HORTICOL CROPS

D E S C R I P C I O N

OBJECT OF THE INVENTION

The present invention relates to a process for obtaining polymeric raw materials for industrial application, from plant residues mixed with polyolefins raffia from agricultural crops, mostly from agricultural greenhouses, subjected to fermentation. The products obtained according to this invention are widely implemented from a commercial point of view.

BACKGROUND OF THE INVENTION

A good part of the agricultural residues coming from agricultural crops and, in particular those coming from greenhouses, are mixed with raffia of polyolefins used in the tutored of the plants, reason why it is not possible its utilization like cattle feed and, on the part of the Environmental Administration, its use in composting facilities is difficult, given the high degree of rejection of non-fermentable material.

This being the case, this waste ends up abandoned in public spaces, contributing significantly to environmental pollution or, in the best case, buried in landfills. Its management of valorization is not yet resolved and is the object of the invention.

Organic matter composting procedures are well known in the art: crop remains, grass mowing, weeds, pruning branches of fruit trees, leaves, fruit and vegetable remains, slaughterhouse animals, marine plants, et. But always the material used is entirely organic, not mixed with other non-fermentable products such as olefinic polymers.

5

10

fifteen

twenty

25

30

TECHNICAL PROBLEM PROPOSED

As indicated above, it is of high environmental and economic interest to solve the problem of plant residues from crops in which raffia tutored is used, so practices conducive to its use as biomass using laborious technologies have been tested. expensive for the separation of the plant part of the polymer and, therefore, currently they are not applicable. Also, the composting techniques used today generate a rejection that cannot be used and, as mentioned above, ends up buried in landfills, at best.

Given the great abundance of plant residues mixed with plastics, it is an improvement to develop a process of separation and valorization of both components.

DESCRIPTION OF THE INVENTION

Vegetable remains mixed with polyolefin raffia residues, mainly from agricultural greenhouses and after reducing their size by crushing, are subjected to a composting process, for example by aerobic fermentation or by any of the procedures described in the art, either in open systems (stacked or static batteries) or in closed systems (vertical or horizontal reactors). In this way, rejections of non-fermentable residues (raffia) mixed with vegetable remains and powdered compost are generated.

This rejection is transported to a crusher, and is crushed by any of the size reduction procedures known in the art, preferably by a suitably sized rotary blade system so that the raffia can be cut into small pieces (preferably 4-10 cm ) without being rolled into the mobile parts of the crusher that would end up immobilizing and damaging it.

The crushed material is pneumatically transported to a cyclone, whereby most of the powder compost that accompanies the raffia is separated. The plastic thus recovered,

5

10

fifteen

twenty

25

30

With a low percentage of impurities, it is suitable for use in pyrolthic recycling plants to obtain solid, liquid and gaseous hydrocarbons by known processes, some of the same author of this invention, as for example the one claimed in national patent ES2409061 (B1) .

To use this plastic as a raw material in other recycling processes, such as extrusion molding, blowing or injection of parts, it is necessary to wash it with water and then dry it by centrifugation, pneumatic transport or any other procedure.

The washing waters, as a consequence of the composting process to which the material has been subjected, in addition to carrying dissolved nutrients leave very colored and potentially contaminated with the fermenting microorganisms. That is why you have to undergo purification before being poured abroad or, better yet, recycle them and use them in the composting process to irrigate the material that is being fermented, so it is very convenient to develop all the operations described in this invention in the same composting facilities.

The material resulting from this cleaning process is still impurified by small particles of plant nature since these and the plastic have similar densities, so it is not possible to separate them by flotation in water and they would leave together in the previous washing process.

One of the characteristics that make polyolefins useful for their widespread use in ordinary life is their insolubility in most of the usual solvents. But if liquid substances of a chemical nature similar to these are selected, such as hydrocarbons, and under suitable temperature conditions such as between 150 and 250 ° C, preferably 180-200 ° C, it is possible to dissolve them by keeping the plant remains in suspension for being insoluble in these solvents and conditions.

Thus, by dissolving in a stirred reactor, hot filtration, precipitation by cooling and collection of the polymer solid by means of compaction and vacuum techniques, storage is carried out, while the solvent is taken to a tank

5

10

fifteen

twenty

25

30

Independent.

Thus, the general object of the present invention is multiple:

• Remove plant and plastic waste from the environment, giving them commercial utility.

• Establish based on the procedure a conversion of these wastes into a market product, such as compost, and a raw material to be used industrially (plastic).

• Select the appropriate conditions so that the separation of both products takes place conveniently.

DESCRIPTION OF THE DRAWINGS

To complement the description that will then be made and in order to help a better understanding of the features of the invention, in accordance with a preferred example of practical realization thereof, an integral part of said description is accompanied, a plane in which With an illustrative and non-limiting nature, the following has been represented:

Figure 1 shows a block diagram corresponding to the different stages and means used in the implementation of the procedure performed in accordance with the object of the present invention.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the abstract figure, there can be seen a conveyor belt (1), by which and after the reduction of size by crushing the plant remains

5

10

fifteen

twenty

25

30

mixed with polyolefin raffia residues and after undergoing a composting process, the rejections generated are transported by means of said conveyor belt (1) to a crusher (2) in which there will preferably be a system of rotating blades that allow the sectioning of the raffia in small portions, preferably 4 to 10 centimeters, without being rolled into the mobile parts of the crusher, which would eventually immobilize and damage it.

Then, and by means of a blower (3), the crushed material is transported pneumatically, through the duct (4), to a cyclone (5), taking place that most of the powder compost that accompanies the raffia is separated .

In this way the recovered plastic, with a low percentage of impurities, between approximately 10 and 15%, is suitable for use in pyrolic recycling plants, allowing to obtain solid, liquid and gaseous hydrocarbons, by known processes.

The plastic, for use as a raw material, is subjected to a washing with water, in a washing plant (6), with an outlet (7) of washing water and an inlet (8) of the water used for washing.

Next, the washed plastic is subjected to a phase of drying by centrifugation, pneumatic transport or any other means, according to the drying train (9) of the scheme of Figure 1, in which a silo (10) of reception of the dried plastic and then of said silo an extractor (11).

From the silo (10) the plastic is subjected to a solution in a stirred reactor (12), then subjecting it to a hot filtration process (13) and subsequent precipitation by cooling (14), after which it is carried out a collection of the polymer solid by means of compaction and ford techniques, for its definitive storage (16).

The solvent is taken to an independent tank (17) from the compaction and vacuum stage (15).

5

10

fifteen

twenty

25

EXAMPLE.

200 Kg of rejections from aerobic composting of plant material mixed with polypropylene raffia belts, inoculated with fermenting microorganisms to accelerate the process, are crushed in a rotary knife cutter to obtain 8-10 cm fragments and pneumatically transported to a silo cyclonic, collecting 38 kg of compost powder and 160 kg of raffia and plant material remains. 10 Kg of these are washed with water and, after manually separating the most bulky plant fragments and air drying, 9.5 Kg of dry product were obtained. 2.0 Kg of this material were subjected to a pyrolysis process following the method described in National Patent ES2409061 (B1), yielding 1.71 Kg of hydrocarbons, of which 87% are liquid at room temperature, the rest being formed by untiring gases ( C1-C4).

2.5 Kg of the product washed with water and dried were dissolved in 10 liters of decalin at boiling temperature. The resulting solution was filtered hot to separate the non-soluble parts (vegetable impurities). By cooling this solution to room temperature, a powdery solid was separated, which by filtration in Buchner and drying in a vacuum gave 2.3 kg of practically pure polypropylene powder, recovering almost all of the solvent.

Claims (1)

5 10 fifteen twenty 25 30 R E I V I N D I C A C I O N E S 1a.- Procedure for the valorization of vegetable remains mixed with polyolefins raffia from vegetable crops, characterized in that it comprises the following operational phases: • Trituration and reduction to small pieces of the vegetable remains mixed with polyolefins raffia; • Undergo aerobic fermentation said plant remains mixed with polyolefins raffia to make them compost; • Separate said compost from the unfermented part, using vibratory filters or other solids recovery systems; • Recovery of compost powder that accompanies unfermented remains, through fragmentation; • Transportation and separation for the recovery of plastic with a low level of impurities (10-15%) suitable for industrial use; • Washing with water from the impurified plastic with plant material and compost remains; • Drying; • Purification of the material washed by dissolution, using as hydrocarbon solvents • Hot filtration of the resulting solution, to separate insoluble material constituted by plant impurities; • Cooling of the clean solution with polymer precipitation • Recovery by means of compaction techniques and solvent fading and clean and dry polymer solids. 2nd.- Procedure for the valuation of vegetable remains mixed with raffia of 5 polyolefins from vegetable crops, according to claim 1, characterized because the aerobic fermentation stage of the vegetable remains mixed with polyolefins raffia, to obtain compost, is carried out in open systems by means of turned or static batteries, or in closed systems by means of vertical or horizontal reactors. 10 3a.- Procedure for the valuation of vegetable remains mixed with raffia of polyolefins from horticultural crops, according to claim 1a, characterized in that the washing water with dissolved organic material and potentially contaminated with microorganisms, is subjected to a recycling process, using it in the composting process to irrigate the material in fermentation. fifteen 4th.- Procedure for the valuation of vegetable remains mixed with raffia of polyolefins from horticultural crops, according to claim 1a, characterized in that the washing water with dissolved organic material and potentially contaminated with microorganisms, is subjected to a purification process, before being poured abroad. twenty