Di-ammonium phosphate (DAP) fertiliser. It is
the most popular phosphatic fertiliser because
of its high nutrient content and good physical
properties. The composition of DAP is 18%
Nitrogen and P2O5 46%. Within the same facility,
Hindalco can also produce nitrogen phosphorus
potassium (NPK) complexes as value-added
downstream products. It can manufacture NPK
complexes such as 10:26:26, 12:32:16 and
20:20:0.
The traditional fertiliser used in planting of
maize and wheat in Rift Valley is DAP. It
contains 18 per cent N and 46 per cent P2 O5. In
the current season, DAP had not arrived in
stores of National Cereals Board by the time
farmers were planting. The extension officers
were persuading farmers to use the available NPK
(23:23:0) that contains 23 per cent N and 23 per
cent P2 O5 arguing that it is better than the
DAP because it does not increase soil acidity.
The farmers objected arguing that they wanted to
use the fertiliser they trusted — DAP. Actually,
NP fertiliser is more concentrated in nitrogen
but weaker in phosphate. Since the farmers have
been using DAP over the years, it is unlikely
that the soils require such a fertiliser. To
clear the air, a simple test called phosphate
fixation capacity can indicate whether the soil
requires phosphorus fertilisation every season.
The argument by extension officers that the NPK
fertiliser is superior to DAP because the latter
does not acidify soils is highly debatable.