Briquetting


The briquetting process is simple and easy to learn and could give many people the possibility to not only gain an income from selling the nut residues but also from working in briquette-making.
Several options for briquetting equipment exist, there is no wrong or right choice. Pretty much every technology will bring out some kind of result when applied to any material under any production condition. Choosing wisely will however influence factors such as durability of the equipment as well as the quality and durability of the briquettes.
 

Technical aspects of DIY Brazil Nut  residue processing

From an engineer's technical point of view, the production of briquetts from Brazil nut residues consits of three components: (1) breaking the nutshell into smaller pieces, (2) grinding the pieces to a sawdust-like consistency, and (3) compressing the grinded material into briquettes. Of the three steps, and particularly under the DIY paradigm, the most challenging step is number 2, the grinding of the shell parts.
The initial (1) breaking of the nutshell is done straightforwardly by applying a strong mechanical impulse on the nutshell. Anything from a sledgehammer to any form of an enlarged nutcracker will do the job; the task is to organize the workflow and the role of human agency in the process as efficent and safe as possible.
The (2) grindig of the nutshell parts on the other hand really is a hard nut, as the German idom goes. The technique we are following to crak this nut is dirived from pre-industrial milling technologies. We work with the classical system of two round millstones, one sitting on the other spinning around a shared vertical axis. Between the two discs the nutshell parts are grinded down to a suitable size by friction and shearing forces. The main task for this step of the process is to dimension the millstones properly, so that they can be (a) produced and installed on site, (b) operated without electrical or combustion engines, (c) maintained and reproduced locally and independetly.
The last step of the process is the (3) compression of the grinded nutshells. To achieve this, the dust is mixed with water and the mixture pressed into a perforated pressing mold. As the pressure rises, the water is forced out of the mixture and the lignin in the material diluted. As soon as the pressure is released, the lignin immediately hardens out again and stabilzes the form of the resulting briquette. For this step, it is crucial to establish the optimal lever arm for compressing the material, as well as developing further the many DIY-systems that are already available on the internet and other sources. The aim is to design a compression mechanism suitable for producing briquettes in a scale that is capable of potentially tapping into markets beyond subsistence economies.


Buildung the millstones. Image: Jan Bovelet, 12.11.2013