University of Alicante

The Research Group "Waste, energy, environment and nanotechnology" (WEEN) from the University of Alicante has developed a new compact material and a production process of briquettes with high energetic content, in order to carry out a proper and viable treatment and energy recovery from waste from the furniture industry (wood and upholstery foams mainly).

Due to the flexible character of polyurethane foams, a densification of separate foam is not simple. The solution provided in the present invention uses a mixture of the two components (wood and polyurethane foams) for briquettes.

The compacted material developed is formed mainly by biomass and foam (Figure 1). Whereas biomass (lignocellulosic) consists of waste wood or timber products, the foam is composed of polyurethane foam or similar from sofas, cushions, pillows, chairs, mattresses, etc.

Figure 1.- Initial mixture of furniture waste with polyurethane foam

The method for producing briquettes of the present invention comprises the following steps:

1) Crushing of wood waste and foam to a certain size.

2) Compacting of the material obtained into the shape of briquettes by a hydraulic piston press briquette machine.

In the different laboratory assays, the research group has studied and defined the process parameters, which are the most influential on the physicochemical characteristics of the briquette such as: percentage of mixture of materials, the size of crushing, appropriate humidity and compaction pressure.

As a result of this research, we have obtained briquettes with physicochemical characteristics similar to conventional briquettes (made of wood) in terms of resistance to fragmentation and abrasion, durability (DU - according to European standard CEN-TS 14588: 2003), density and calorific value, appropriate for use as industrial fuel (Figure 2).

Figure 2.- Briquette obtained with a mixture of furniture waste and polyurethane foam

Through this procedure can, briquettes of 53 mm diameter and variable height between 20 and 60 cm be obtained, although the process is applicable to any size briquettes. Furthermore, the briquette can have any shape, either in brick, cylindrical, tablet-shaped, square or the like.

• The new briquetting process from waste furniture solves the current problem of management of this waste.

• The process allows energy recovery and treatment of this waste in a simple and feasible way to avoid the environmental problems associated with disposal in landfills.

• The densification of the material in the shape of briquettes makes the transportation, handling and storage of this waste easier and cheaper.

• The briquettes produced have high energy density and have physicochemical characteristics (resistance to fragmentation and abrasion, durability, density, etc.) similar to conventional ones.

• The briquettes can be used as fuel in thermal power plants or industrial boilers, solving the drawbacks of low density, uniformity of size and shape, as well as the feeding problems in these combustion plants associated with these materials.

• This process can be applied to briquettes of any size and shape.

The manufacturing process has been successfully tested in the laboratory and a pre-industrial scale. The research group has made various studies in which various parameters have been studied, among others: the size of crushed material, amount of foam mix (5-35%) moisture and compaction pressure (30-100 MPa).

As a result of this research, we have obtained briquettes with similar physical-chemical characteristics to the conventional briquettes (fragmentation resistance, abrasion, durability, density and calorific value) fully appropriate for use as fuel for thermal power plants or industrial boilers conventional briquettes.

For these tests, a hydraulic piston press briquette machine has been used (Figure 3) to obtain briquettes with 53 mm diameter and a variable height between 20 and 60 cm, although the process is applicable to any size and briquette shape (brick, cylindrical, tablet-shaped, square or similar).

Figure 3.- Hydraulic piston press briquette machine used

Municipal solid waste treatment plants or furniture industries interested in the energy recovery of this waste.

Companies interested in acquiring this technology for use and / or commercial exploitation, through the following:

• License agreements to transfer the patent rights to use, manufacture or marketing of the technology to third parties.

• Agreement R & D project (technical cooperation) for the use or application of technology in other waste or in other sectors.

• Subcontracting agreement for technical assistance, training, etc.

This technology is protected by granted patent.

• Patent title: “Procedimiento para la fabricación de briquetas para la valorización energética de residuos de muebles”

• Application number: 201530678

• Application date: 18/05/2015