Zeolite can remove ammonia in RAS

What is magnificient of Zeolites?????

Zeolites are crystalline aluminosilicate minerals that can be found in rock deposits throughout the world. They are formed by a process known as devitrification or crystallization of volcanic ash, a process that takes place over millions of years when lava remains in contact with fresh or salt water. The word 'zeolite' itself is an amalgam of the two Greek words for 'boiling stones' because of the steam that is given off when these rock crystals are heated, due to their high water content. Zeolites have a molecular stacked-cage or honeycomb structure formed of silicon and aluminium oxides, and as a result of the electronic configurations of the aluminium, silicon and oxygen that make up these tiny zeolite cages, each has an overall negative charge which means that they electrostatically attract positively charged ions and other particles, in much the same way that a magnet attracts iron filings.

Molecule structure of zeolite

Oxygen and ammonia are the two most important parameters in aquaculture operations. While oxygen can be easily controlled ammonia on the other hand is much more difficult to mitigate and is highly detrimental to the health of fish. The natural generation of toxic levels of ammonia (NH3) and hydrogen sulphide (H2S) by large densities of fish in aquaculture operations affects fish tissue, growth rates, oxygen utilization, disease resistance and causes mass mortality.

Zeolite is currently used in commercial fish farms to reduce ammonium (NH4) and hydrogen sulphide levels resulting in increased growth rates and population densities. Zeolite is also used during fish transportation allowing the delivery of more fish over a longer period of time.Zeolite has a high selectivity and capacity for ammonium via cation exchange capacity (CEC). Once the ammonium ion is within the zeolite lattice, it is not water-soluble.

When used as an ion-exchange filter medium the zeolite can reduce ammonium content of circulating freshwater from aquaculture systems by as much as 97%. Piper and Smith (1982) suggested that a water recycling system with a zeolite filter system can allow up to a 10 fold increase in fish density. Zeolite also reduces ammonium content in discharge waters in order to meet environmental requirements.Zeolite is 100% natural, durable and can also be simply regenerated using a brine solution (with a rinse) for repeat cycles of this ion exchange filter bed. Zeolite can also be broadcast over the surface of a pond to be effective in reducing ammonium.

The pond-bed sludge can be recovered and used as a nutrient enriched slow release fertilizer.
The required zeolite quantity for your operation depends on water pH, temperature, volume along with fish species and population density. When the optimum quantity of zeolite is used, the ammonium level is reduced at a rate highly dependent upon the rate of water movement. A variety of systems have been designed for reduction of ammonia in fish rearing environments.

Zeolite also provides a substrate for bacterial populations in order to breakdown ammonium to nitrate (NH4 to NO3) and remains effective as a chemical filter capable of modifying fluctuations in the system's ammonium levels. This enhances the biological functions making ammonium available to bacteria at a stable level, thus enabling the bacteria to remain abundant during periods of low ammonium contamination. The bacterial population will therefore survive during dramatic changes in concentration.There are three filtration processes to reduce ammonia in the water:

Mechanical filtration of unused food and fecal material.

Zeolite is much more effective than sand and charcoal filters due to nominal rating of 3 to 5 microns (sand is typically 20 microns) thereby increasing loading while reducing the amount of backwashing. Refer to the ‘Water Filtration’ menu item in the Industrial Section.

Biological.

The tremendous surface area and irregular surface of BRZ Zeolite provides an idea media for aerobic bacteria. The bacteria mineralize the organic nitrogen compounds. The process can be aerobic (nitrification) or anaerobic (denitrification). Nitrification is most common and involves the oxidation of ammonia to nitrite to nitrate by autotrophic bacteria.

Chemical.

Due to its large cation exchange capacity zeolite is an excellent filter of ammonium and certain heavy metals.