Online Reporter
THE magnificent effort by Zimbabwean farmers to expand the range, varieties and volumes of Zimbabwean crops would be impossible without adequate supplies of fertiliser and other agricultural chemicals, many of which have to be imported.
Since Africa as a continent is generally short of fertilisers, there are many good reasons why we all need to build up our national, regional and continental production to make sure our farmers have enough.
When shortages arise it is quite natural to cut back on exports and so Zimbabwe, like many countries, wants a higher level of self-sufficiency so we are not the export customer being cut back.
The Second Republic has seen some serious growth, with more planned, in the fertiliser manufacture field. Gaps in our raw materials’ supplies are being filled wherever possible by intermediate products from other raw materials.
Starting from the beginning of farmer’s requirements, lime is now in ready supply as the cement industry upgrades its own materials supply chain, with conversion of limestone into lime being needed for both the cement ingredient and the powder farmers with acidic soils need to correct pH levels.
This sort of basic chemical industry with multiple customers builds up efficiencies, and so cuts costs.
One of the few countries in Africa with a reasonable deposit of phosphate minerals, Zimbabwe has had local processing for some decades.
There were some bad patches, but these have been overcome and a range of phosphate products for blending with other fertilisers in compounds, or for direct use, are now available.
The processing has seen the establishment of a more complex chemical industry as well, with applications going far beyond agricultural chemicals.
Unfortunately, like much of Africa, Zimbabwe does not have deposits of potassium salt minerals. The strong igneous geologies make such deposits likely to be scarce, but we should continue looking.
In theory, the phosphate deposits should also be rare and we lucked out there.
There are chances that potassium mineral deposits can be found in some estuaries and other water fed areas, and the Congo River mouths may be our best bet. We can trade for other fertilisers.
Nitrogen fertilisers are needed in the largest quantities and have the widest range of sources. Most nitrogen fertiliser comes from ammonia, usually as ammonium nitrate.
Slightly more concentrated ammonium salt, urea, is also fairly common and these days much of the world’s urea comes from inorganic sources, although it started off as the fertiliser produced from organic waste.
At one stage, Zimbabwe managed to make quite a lot of its then limited requirements of ammonium nitrate using very cheap surplus power from Kariba South to extra nitrogen from liquefied air and hydrogen from electrolysis of water, the “waste” oxygen from the two processes sold to Zisco for its steel technology.
This was considered an old fashioned and uncommon ammonium production process, although other countries with very cheap surplus electricity such as Norway have used it.
When Zimbabwe’s electricity demand grew, other more expensive sources of power, such as coal thermal, had to be used.
The final stages of the technology process were still in place in Kwekwe, but another source of ammonia was required. Most of the world’s ammonia is now made from natural gas, which is why Mozambique is a major source.
As the Muzarabani gas field is brought into production, one of the plans is a gas pipeline to Kwekwe to fuel a chemical industry, including ammonia.
But now another investor is keen on building a US$400 million urea plant in Chiredzi district. The Government will be spearheading the investment through Verify Engineering in partnership with a Chinese investor.
The location of a coal mine that has been operating for more than two decades, a decent water source and customers almost on site within the vast Lowveld makes this investment viable.
The way urea is made, with synthesis gas, a blend of carbon monoxide and hydrogen as the intermediate raw material between coal and fertiliser, means that other industrial materials could also be made.
We do not need to worry much about having multiple fertiliser factories.
The high bulk product is a bit like cement; you want the manufacture to be as close to customers as possible to manage transport costs.
In any case, the need for dramatic increases in output means that every additional factory can be selling to customers quite quickly. When production is short filling gaps is viable and profitable, and simply requires sources of investment.
Other countries have used the build-up of fertiliser production as a way of building up their chemical industries, and these are among the critical foundations of a modern industrial sector able to go far beyond assembly of consumer goods into the core of heavy industry. So a modern and diversified fertiliser industry, like other diversified heavy industry, builds up the manufacturing base as well as the food and agro-industrial base.
