Page 126 - CW E-Magazine (5-8-2025)

Point of View

With the area under salt production unlikely to
expand significantly, much will depend on raising Indian Salt - production, consumption and exports [mt]
productivity. This is dependent on several factors, 35 28.9 30.8
some beyond the control of producers – the number 30 27.6 29.2 30.0 28.0
of wet days; density of the seawater; type of soil; rate 26.9 10.2 26.6 26.6
of evaporation (which is dependent on the intensity 25 23.0 8.0 6.9 11.8
of solar radiation); humidity; and wind velocity. But 20 5.7 6.6 8.4 10.3 6.7
industry experts reckon salt productivity can be raised 6.0
to 90-100 tonnes/acre from the present 60 tonnes/ 15 14.5 11.2 10.2
acre, with the right technological interventions and 10 11.0 11.5 11.3 11.1 11.1 13.0 10.2
policy support.
5 7.5 7.9 6.7 7.4 9.5 9.8
Improving quality 0 5.5 6.1 6.2 6.5
While the earlier technologies for caustic soda – FY14 FY15 FY16 FY17 FY18 FY19 FY20 FY21 FY22 FY23
using mercury or diaphragm cells – did not need Edible use Industrial use Exports Production
high quality salt, that changed with the advent

of membrane technology, which India’s industry Source: Alkali Manufacturers Association of India

enthusiastically adopted. In these plants, the quality of salt not only determines the efficiency of the overall process but, importantly, the
lifespan of the expensive, imported membranes. Important parameters that membrane-quality salt needs to match include purity of sodium
chloride, and the amounts of calcium, magnesium, sulphate, iodide, bromide, and total organic carbon (TOC). The chlor-alkali industry also
specifies limits (in parts per million) for elements like chromium, barium and aluminium. While some upgrading of the brine is done by caustic
soda units prior to pumping into electrolytic cells, it falls upon the salt industry to better its quality.

There are two stages of efforts taken to improve brine quality by salt producers: pre- and post-harvesting. The former includes the quality &
management of brines and the processes adopted, while the latter includes mechanical washing and chemical treatments. A combination
of both is needed to ensure the quality desired.

An important aspect is to optimise processes to account for differences in brine quality – not just between States, but even within one.
For example, brines in inland Rajasthan have higher levels of insolubles, sulphate, TOC, iodide, bromide, carbonates and bicarbonates, as
compared to ones from Gujarat, making the former unsuitable for caustic soda making.

Diversifying product slate
Salt manufacturers should also examine opportunities in higher value products such as pharmaceutical grade salt – demand for which
is globally on the rise and supplier base is limited to only about 25 producers. Dialysis is the most important application for this premium
product, accounting for 75% of its demand. India’s major salt players (and others) have also built sizeable capacity for bromine, and further
value addition opportunities are available downstream. The global demand for bromine is rising at a CAGR of 4%, with Asia-Pacific growing
at nearly twice the pace. While the US and Israel lead in bromine production, India is not far behind and has the potential to move up to
number two spot, if not pole position, in the next few years.

The prospects for supply of pure brine from salt works via pipelines to the chlor-alkali industry, instead of transporting solid salt to be
converted into brine at the latter’s facilities, is also worthy of consideration.

Challenges ahead
In coming years, the salt industry will need to adapt to the changes brought about by a warming planet. Changing weather patterns in Kutch
and Bhavnagar, for example, have reduced the number of sunny days, and in some years the number of days for salt harvesting has halved
from 240 to 120. Combined with more rains, this has led to lower overall productivity. More and severe cyclones are also landing in Gujarat.

If the Indian salt industry is to improve its competitiveness in global markets, it will need access to better infrastructure – in the form
of roads, railways and ports.
The industry will also benefit from a modernisation of rules and regulations governing it. Many are archaic and framed during British
rule. The Indian Salt Manufacturers Association has been demanding the classification of salt as a seasonal agricultural product, instead
of a mining product, as just 0.5% of total output comes from mining and the balance is produced from seawater or sub-soil water. There is
merit to this demand.
Ravi Raghavan

126 Chemical Weekly August 5, 2025

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