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From 2011.igem.org

Aims

If in the future biorefineries become prevalent in the way we source our food and energy, cellulose is likely to play a significant role. The Edinburgh team’s biology work attempts to make strides in how to effectively harness cellulose’s potential. If it proves that enzymes working in synergy can degrade more cellulose than the status quo, then the impact is effectively large, as a 1% increased efficiency in the lab would be significant in on industrial scale.

The implications of such a project or any other advance in this technology could mean that more biorefineries are built, continuing the growth in this industry. Edinburgh’s human practices work is concerned about understanding the implications of this technology for society. In earlier sections we asked what the technology would look like, whether it is feasible and what the economic implications are. But what of the effects on the environment? In this section a life cycle analysis is carried out which aims to identify possible environmental concerns. The analysis will follow the path of waste paper from its origins, then into the biorefinery process and afterwards. While many life-cycle analyses look directly into the impact of carbon numerically, this analysis is purely qualitative.

Graphical analysis

Analysis

• Paper waste is used as the primary raw material in the biorefinery. In the status quo is paper is recycled to make more paper. However a certain percentage is turned into waste. Is it possible to take that percentage and use it in the biorefinery? The composition of cellulose is the determining factor which would need to be examined. If the raw materials were made up of pure biomass then the implications to the environment would be proportionally greater. Therefore locally sourced biomass, which does not impact on agricultural land, is the preferred option.
• Currently the biorefinery is an energy and chemically intensive process. The amounts needed to convert 700 kg/h of raw materials into glucose is substantial. But, as outlined in the biorefinery design section, synthetic biology may hold the answers to a reduction in energy required (i.e. using a recombinant enzyme for the conversion of lignin into phenols bypassing the energy intensive hydrous pyrolysis).
• A method used widely in Scandinavia is using excess heat from the plant and transferring it to local communities. This would mean the biorefinery would have to be situated close to a populous town/city which could have implications of its own.
• By converting waste paper to sorbitol and then to toothpaste, the biorefinery which uses synthetic biology prolongs the life of paper. Toothpaste tubes can then be recycled into plastics.