Ecological aplication

Sorbent barriers for radioactive waste:


Permeable barriers incorporate sorbent materials, including zeolite, to selectively contain contaminants that are percolating from shallow land burial sites of low-level radioactive waste. The zeolites are combined with clays and other materials that retard the migration of leachate for a period long enough to allow exchange and/or decay of radioactive ions.

Radioactive waste treatment:
Natural zeolite has a high ion exchange capacity and a particular affinity for heavy metal cations. It can absorb elements such as strontium 90, caesium 137 and other radioactive isotopes from solution, and hold them in its 3 dimensional crystal framework. Zeolites react readily with cement and glass systems thus allowing the radioactive waste to be entrapped and contained safely. Zeolites are physically robust and resistant to nuclear degradation, and they are less expensive than organic ion exchange resins.

Zeolite as a filter media

Zeolite is the Superior Pool Filtration Media compared to
Natural zeolite offers a unique three-dimensional-honeycomb structure and rough, pitted surface.

Zeolite’s crystal structure, irregular surface, and high surface area make it a highly effective trap for fine particulates and ammonium ions.
Microporous zeolite media contains a large surface area for entrapment of suspended particles down to colloidal size.

Angularity of zeolite grains and tapered internal pore spaces allow for removal of suspended solids by bridging, straining, adhesion, adsorption and flocculation.
Zeolite, will remove ammonia from water. This reduces the need for chlorine and the formation of chloramines. The porous structure of Zeolite is imbued with sodium ions, which remove ammonia ions through ion exchange.
Lower ammonia ratios enable a better water balance and a reduced need for supporting chemicals. For this reason total dissolved solids are more easily controlled, providing reduced turbidity levels.
Benefits of Using Zeolite:
• Improves Water Clarity
• Filters Particles Down to 3 Microns
• Greater Surface Area
• Superior Purification
• Greater Ammonia Absorption
• Reduces Chloramines, Odors and Eye Burning
• Chemical Demand and Need for overchlorination is Reduced
• Saves Water and Energy
• Doubles time between backwashes
• Natural and Environmentally Safe
Zeolites are a group of natural minerals that have certain properties that enable them to exchange one charged ion present in their crystalline structure, for another one present in the surrounding media.

Zeolites are capable of exchanging sodium ions (Na+ ) for Ammonium ions (NH4+). What this means is that when Zeolite are added to the pond, any toxic ammonia present in the water is taken into the zeolite in exchange for harmless sodium ions.

Zeolite is an efficient ammonia remover and also provides a large surface area for nitrifying bacteria in recirculating systems.
Zeolite does not only provide optical clearness of your water, but it also keeps it biologically clean.

ZEOLITE IN WASTE WATER TREATMENT

 
Current wastewater treatment processes usually improve the quality of effluent water by enhancing the efficiency of the pollutant reduction process or by increasing the retention time of the wastewater in the treatment facility. The latter approach however requires a larger aeration basin and higher operation cost resulting in an expensive solution.
 
One of the most promising approaches to improve the efficiency and increase the capacity of wastewater treatment plants (WTP), without increasing size, is based upon application of natural zeolites in the aeration basin. Zeolite particles are good carriers of bacteria, which adsorb on the zeolite surface resulting in increased sludge activity.
ZEOPOL is developing a new modified zeolite and process which can accelerate the interaction between zeolites and activated sludge and increase further the sludge activity. The effects of modified zeolites on organic degradation rates will be tested at laboratory and full-scale experiments applying activated sludge technology.
In order to increase the beneficial effect of zeolite or to promote interaction with co-additives, natural zeolites can be modified or activated. The modification means, e.g., dealumination, increase of pore size by acid treatments, transformation of polycationic natural zeolites containing mainly Na+, K+, Ca2+, Mg2+ exchangeable cations into monocationic, e.g., into Na-form, by exhaustive ion exchange.
Zeolites can remove heavy metals by ion exchange. The ion exchange selectivity depends on the type of zeolite, pH, heavy metal itself, counter ion, ion concentration, and presence of other cations. An effective removal of heavy metal ions is achieved through ion exchange. For example, clinoptilolite is a suitable ion exchanger to decrease the heavy metal content of weakly alkaline wastewaters from several 1,000 ppm to 10 - 100 ppm.


Other benefits of natural zeolite application
 
  1. Agricultural application
Due to the fact that Zeolite contains dioxide of silicon, aluminium, calcium, potassium, iron and other substances important for plants, it is applied as an individual, separated fertilizer. Accumulation properties of Zeolite promote moisture retaining in soil of arid zones.
 
15-20 tons of Zeolite per one hectare of soil increases harvest of:
    1. silage corn: from 2.5 up to 4.5 ton per hectare
    2. grain corn: from 0.13 up to 0.28 ton per hectare
    3. wheat: from 0.13 up to 0.31 ton per hectare
    4. potatoes: from 0.5 up to 0.67 ton per hectare
    5. barley: from 0.25 up to 0.35 ton per hectare
Application of Zeolite allows achieving 100 percent seed germination. Due to the fact that water in Zeolite doesn't freeze even at -20 0C temperature, plants acquire high frost-resistant properties.
The most effective Zeolite usage is its combination with organic fertilizers (ratio is 2:1 or 3:1). During regular application of organic fertilizers 30-80 percent of fertilizers are washed away from soil or become hardened - so they remain unutilized. In case of combination with the mineral, Zeolite absorbs fertilizers and distributes them to the plants during the whole vegetation period. As the result fruits and vegetables absolutely get rid of radionuclides and content of nitrites in plants decreases by two times.
Zeolite is indispensable in commercial hothouse gardening where it is used as an individual substratum in combination with peat and humus. Berries, fruits, vegetables, flowers in such conditions germinate 15-30 days earlier than usually.
Effective action of Zeolite is persistent within 10 years after its first application. Practice shows that Zeolite using as a soil conditioner is compensated in two years and provides stable profits in four years.
  1. Sanitation and odour control

Zeolite resolves a great sanitary problem related to presence of unpleasant smells on farms dung depositories within the city's limits. One kilogram of Zeolite is sufficient for absorbing of 100 grams ammonia. In 15 minutes 150-200 grams of Zeolite completely remove the unpleasant smells from 1 m2 area within the buildings.
  1. Fish breeding
Concentration of Ammonium in artificial ponds very often destructively influences on fauna development. Being an excellent absorbent, Zeolite can entirely prevent from ammonium ion accumulation and water stagnation in reservoirs. It is also used for fish feeding in the combination with biological additions.

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