Minerals and Energy Sources

Abstract

Salt can be considered as the most widespread mineral in Eastern Africa and its recovery from the sea is a comparatively simple process given certain environmental conditions. The location of solar saltworks is controlled by the rainfall regime and the occurrence of suitable impermeable soils. These conditions occur from Ngomeni northwards to the Lamu area. Extensive saltworks have been established at the Gongoni-Fundi Is area and Kurawa. The total area dedicated to salt production is over 5,000 hectares that yield an average of over 170,000 tonnes of salt annually. The method of salt production utilised by the five established companies is very much the same throughout the area. Seawater is introduced into the ponds which are run in series. Slight variations may occur in the method of filling the ponds which utilize tidal energy. In the first pond, undesirable salts of low solubility are removed and the water then flows into concentration, evaporation and crystallization ponds. Crystallized salt is gathered from the ponds, processed and taken to market.