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Thursday, October 22, 2009

Wood Waste and Urea

There is a pretty wide agreement that if we don't reduce the level of greenhouse gases in the atmosphere, we are all going to hell in a hand basket. Some people believe that we have already gone too far and no matter what we do, it is too late. Others believe that with the head in the sand attitude of most world leaders, there is very little chance that we will succeed in making any significant reduction in our output of fossil carbon. Assuming that the above is true and the world will not gain control of her carbon emissions, what can New Zealand do about it.

Of course we should take measures which establish our credentials as responsible world citizens and reduce our output of green house gases. Quite cynically, this is important for our marketing.  More important, though, is to future proof New Zealand against the possibility of the break down of the ecology of the rest of the world and with it the demise of their economies. Our main trading partners are in the Northern Hemisphere and their demise is going to impact us severely.  There are many many measures we can take.  Below is one regarding our fertilizer supply which will both bolster our credentials for our export market in the near term and help future proof New Zealand against the likely coming breakdown in the world economy a few decades hence.

Sawdust into urea
It has been proposed by our New Zealand SOE, Solid Energy that they turn their lignite deposits into urea for the farmers. At present we import some of our urea so this would help our balance of payment, provide jobs and enrich holders of shares in Solid Energy (MP's???). So far so good. However, it would become the largest emitter of Carbon Dioxide in the country, even surpassing our large coal fired power station at Huntly. It would increase our atmospheric carbon output by 20%.  Is there another way. Well, yes there is*. You can make urea from almost any carbon based substance from methane to pure carbon. You can also produce urea from wood wastes.

*here is yet another way to obtain our fertilizers.

In New Zealand, we have a number of sources of such wood wastes. This includes the branches cut off pine plantations when they are trimmed to make clear wood (lifts), it includes trimmings during logging, the sawdust and off cuts from lumber mills, the left over wood ends from building construction and furniture manufacture plus wood from demolition sites. In addition, all waste paper and cardboard, which is nearly pure cellulose, can be added into this mix. It is pretty clear what the objection of Solid Energy is. Clearly they want to make profit by the vertical integration of their lignite deposits and a Urea plant. The first objection they will make is that the transportation costs of bringing this material from all over the country to their plant will make the feed stock(wood, paper etc) too expensive. So lets agree that whatever happens, they will pay the same for this material as it would have cost them to mine their lignite and transport it to the urea plant. If necessary, we will use government subsidies to make the use of wood waste instead of lignite, financially neutral.  This may sound counter productive at first but bear with me a moment.

However.............Of course we must take into account the carbon tax they will be charged if they do decide to use their lignite.  We have been generous to a fault by signing up to Koyota and have taken upon ourself the obligation to pay a carbon tax.  The use of lignite will incure an added cost which must be taken into account.  Once the Carbon tax is taken into account it remains to be seen, if a subsidy would still have to be paid for getting the wood waste to the company. Wood and paper have no carbon cost because they are recycled carbon recently removed from the air.   We must also factor in the likely effect on our tourism industry and our food exports of becoming the bad boy of the OECD with respect to our lack of carbon abatement. When all this is taken into consideration, it may well be that the use of wood and paper waste to make urea will be cheaper to New Zealand than using lignite.

Then we come to the effect on our railroads. Rail is the ideal medium for transporting high bulk low value products. What is good about transporting wood waste by rail is it gives them another revenue stream which can be used for maintaining and upgrading their infrastructure. This contributes to making the shipment of all other goods by rail more cost effective. We might even put the wood-transport revenue stream into electrifying our railways, further reducing our carbon footprint and so further increasing New Zealand's financial viability with respect to our carbon output. (not to mention our clean green credentials).

Another important aspect is the greenness of our meat exports.  New Zealand meat is for the most part grass fed.  In so far as this is true, our meat is carbon neutral.  The carbon contained in our meat is carbon recently removed from the air by the grass the animals eat.  At present we use fossil fuel to produce our urea which puts a carbon cost on our meat.  When other countries such as the UK try to interfere with our meat imports to their country, they often quote carbon miles.  In actual fact, the carbon footprint of our meat, even when transport is taken into account, is lower than meat they produce.  If we produce our urea from wood waste, our meat is even more carbon neutral.

There is a desperate need to calculate true costs when making economic policy. In this case, with our blinkers on, the use of lignite might be less expensive than the use of wood waste to produce urea. However, when all the benefits of using wood waste and the costs of using lignite are taken into consideration, the outcome is very likely to be quite the opposite.

ps.  On Jul 26,2011 on morning National Radio there was an announcement of plans to construct a turpentine plant for producing, not surprisingly, turpentine from forest waste.  This points to a couple of things.  First, it is apparently going to be financially feasible to bring the feed stock from the forests to the plant.  This suggests that it also might be feasible to bring wood waste to a urea plant.  The second thing is that as far as I know, after turpentine is distilled out of forest waste, what remains is the wood minus the pitch.  This is cellulose, hemicellulose and lignin which is exactly the feed stock that is needed for a urea plant.  All the other feed stocks mentioned above can also  be fed in.  Some of them, such as the offcuts from lumber mills may also be usable for turpentine production. Right beside the turpentine factory would be the ideal site for a urea factory.   The transport cost to each factory is cut in half.

pps.  If our production of urea from wood and other cellulostic waste exceeds our needs, the possibility opens up to export green urea at a premium.  Of course no nitrogen source is green if it is used in excess such that it contaminates ground water but in so far as it is produced from cellulose rather than fossil fuels, our urea would be completely green.