The commonly accepted brine concentration practice in most Chinese Northern solar works is
to pump the sea water into salt works and then let it go through a physical changing process of
natural evaporation, condensation and crystallization, during which, weather factor and the soil
nature have to be taken into consideration when determining the technologic parameters such
as brine depth, brine protection area, fresh water drainage rate and so on. Meanwhile, different
methods should be employed according to various weather conditions, for example, brine is
concentrated with decided depth and salinity over periods of stable weather conditions
(Spring); rapid brine concentration by deep storage and lower depth brine should be used
during rainy seasons; and in winters, the amount should be increased to keep the salinity.
However, accompanying this physical changing process of salt production is balancing
process of the amount of multi-biology in brine. Every salt work fosters an ecosystem, which
includes algae, bacteria, protoza, menatoza, artemia, sea weed and fish communities.
The low salinity brine is featured of a myriad of algae, which are able to synthesize and
accumulate pigments, elevate the brine’s absorbency of solar energy and quicken the
evaporation speed; the algae, bacteria, organic and inorganic substances on the salt ponds
floor may form a biological pad, performing the functions of brine purifying, soil improvement
and leakage protection. At the same time, the biological pad can block out large amount of
elements and trace elements in the mud on the salt pond floor and the bacteria can effectively
decompose organic crumbs of the solar salt works ecosystem.
The medium salinity brine is dominated by artemia, who are good at sieving the algae, organic
and inorganic substances in brine so as to purify it. The artemia corpse are sources of protein
for red halobacteria, which are capable of increasing the brine staining ability, purifying brine
and promoting the evaporation amount and the salt quality.
In conclusion, a balanced ecosystem is beneficial to salt industry by :
A. culturing bentic communities, available for seizing nutrition and controlling leakage;
B. staining brine to enhance the absorbency of solar energy and evaporation rate;
C. being able to decompose most of its self-generated organics.
The Bidirectional Brine Concentration Technology is meant supplementing the ordinary brine
concentration with ecosystem management, namely, through the artificial adjustment of the
amount of biology to reach the eco-balance. This is composed of two parts:
A. The bio-management of artemia. Combining the concentrated multiplication with culturing
during the whole production process to adjust the community density to a suitable level
and keep the eco-balance in line with scientific standards. As long as the brine salinity
reaches certain level and the artemia food chain starts loosing balance, we will fish
over-thick community and let the resting artemia die in the high salinity area and their
corpse will be used for the source of protein for halobecteria.
B. Selecting and culturing excellent breed of halobacteria.. Let red halobacteria reproduce in
saturated brine and crystallizers and contact a corresponding scientific surveillance. This
helps heighten the brine transparency, lower the brine stickiness and promote the salt
quality.
