Zeolite Application in the industry
Zeolite is a natural mineral with excellent absorbency and ion exchange capacity, which makes it a valuable tool for industry. It is widely used in applications such as water purification, wastewater treatment, building materials, and catalytic processes, improving efficiency and reducing the environmental footprint of production facilities.
Composting with Zeolite
Composting is the aerobic, natural decomposition of organic material (manure, plant residues, etc.) by microorganisms, with the main “ingredients” being organic material, moisture, oxygen, and bacteria.
How to Apply Zeolite
Directly onto manure/compost heap
- NH₄⁺ binding before becoming NH₃ → –50% N losses.
- Fewer odors and flies.
- Dosage: ≈ 2% w/w.
- Organically bound N – not directly available.
- Ammonia (NH₃) – volatile, dissipates into the atmosphere.
- Ammonium (NH₄⁺) – beneficial for the soil.
- Nitrates (NO₃⁻) – toxic, water-soluble.
Nitrite (NO₂⁻) – soluble, source of N in the soil.
Benefits of Zeolite in Composting
Reduces odors
- Binds ammonium (source of ammonia odor).
▸Increases the value of compost
- It retains nitrogen; it contains > 3 % K.
Reduces volume & flyaways
- Up to 50% less compost volume; fewer flies due to low NH₃.
Increases crop yield
- Faster germination; 20% higher yield.
Improves soil & microorganisms
- More nutrients, porosity, O₂, pH adjustment.
- It retains 50% w/w water and releases it during drought.
- Protects subsoil by preventing oxidation of NH₃ → NO₃⁻.
- Microorganisms colonize the porous surface.
Regulates oxygen, pH, temperature, and humidity
- O₂ storage, ideal pH, ventilation – herbicide temperature, less evaporation.
- Significantly reduces ripening time.
Composting Parameters
Compost ingredients: nutrients (P, K, Ca, Fe, B, Cu, etc.), carbon & nitrogen.
Ideal C:N = 30:1; maturation: 10-15:1.
Sources C: straw 40–100:1, corn 60:1, bark 100–130:1, paper 150–200:1.
Sources N: sludge 17:1, cow manure 20:1, poultry manure 13–18:1, pig manure 15–25:1.
Microorganisms: aerobic bacteria & fungi – require O₂.
Compost Conditions
Oxygen > 10% (ventilation/agitation).
Humidity 40-60%.
pH 5.5-8.5.
Temperature 55-70 °C.
1.6 Compost Management
1.6 Management Stirring when T < 50°C or < 0 > >
Add water if dry
Duration: 6–9 months • in tanks ≈ 30 days
CO₂ / Moisture Loss: -50% of the quantity
1.7 Odor Management (Causes – Solutions)
|
|
Odor Cause Action
|
|
|---|---|---|
| Ammonia | Low C:N, pH | >Addition of carbon |
| Hydrogen sulfide | Anaerobic conditions | O₂ supply |
1.8 How Zeolite works
NH₄⁺ / K⁺ exchange in the negative crystal lattice
Microbial biomass feeding
Compost with Zeolite → Soil
Contains 3.5% K and +55% moisture (gradual release in dry conditions)
Exchange of H⁺ ⇄ NH₄⁺ → soil enrichment with nitrogen
2. Odor Management with Zeolite
2.1 Industrial & Chemical Environments
Paints, solvents, alcohols, PCBs, MTBE, oil, lubricants, gasoline, urea, acids
2.2 Hospitals & Schools
Vomit, blood, urine, feces, etc.
2.3 Cleaning & Leaks
Stains at airports, meat/fish factories, gas stations
2.4 Landfills & Wastewater Treatment Plants
Landfills, mining waste ponds
2.5 Water Odors
Water for livestock farming, fish farming, drainage
NH₄⁺ binding before conversion to NH₃, algae absorption
2.6 Mold & Fungi in Potting Soil
Natural absorption of moisture and odors
Prevention of mycotoxins
3. Water Treatment & Biological Wastewater Treatment
3.1 Water Purification
Use in ion exchange filters (softening: binding Ca²⁺ / Mg²⁺ ↔ Na⁺)
Removal of pollutants 20–100% (inorganic, organic, heavy metals, radionuclides)
Enrichment with O₂, pH adjustment to neutral
3.2 Biological Wastewater Treatment
Addition to active sludge
Adsorption of particles & heavy metals
Less odors, better dehydration, –50% polymers/phosphate salt
Benefits
90% absorption of ammonium and phosphate
BOD₅/COD reduction > 90%
Destruction of microbes/fungi, reduction of cloudiness
Odor reduction, cohesive sludge (useful as fertilizer)
pH σε ουδέτερο (από >8 ή <6.5)
Retention of organic/organometallic compounds – suitable water for irrigation
Reduction in capital, operating, and chemical costs
4. Air Filtration
4.1 Absorbable Gases
NH₃, CO₂, CO, C₂H₄, NOₓ / N₂O / NO, SO₂, H₂S, CH₄, Hg, Rn²²², VOCs, exhaust gases
20–75% reduction (e.g., NOₓ)
4.2 Ammonia Limits in the Air
| Phenomenon | [NH₃] ppm |
|---|---|
| Odor threshold | 50 |
| Prolonged exposure (TLV) | 100 |
| ½–1 hour exposure | 300–500 |
| Pharyngeal irritation | 400 |
| Eye irritation | 700 |
| Severe cough / cardiac risk | 1700 |
| Fatal (½ hour) | 2500–4500 |
5. Methods of Applying Zeolite
Ion exchange – natural “molecular sieve”
Surface modification with amines (anion exchange)
Enrichment with oxidizing agent (sulfur removal)
Enrichment with bacteria (composting)
Natural molecular trapping sieve
Biofilters (sludge aeration)
Silver enrichment (radon absorption)
Catalytic converter with Pt/Pd (NOₓ)
6. Technical Data on Zeolite
6.1 Size of Microporous Zeolite
| Crystal Axis | Orientation 1 (nm)Orientation 2 (nm) | |
|---|---|---|
| 001 | 0.76 | 0.30 |
| 100 / 102 | 0.47 | 0.28 |
| 001 (άλλο) | 0.46 | 0.36 |
6.2 Diameter of Gas Molecules
CO: 0.376 nm • N₂: 0.364 nm • NO: 0.317 nm • O₂: 0.346 nm
N₂O: 0.33 nm • H₂O: 0.265 nm • SO₂: 0.36 nm • CO₂: 0.33 nm
NH₃: 0.36 nm • CH₄: 0.40 nm
6.3 References (Indicative Bibliography)
Aguilar-Armenta et al., 2001 – Adsorption kinetics of gases in clinoptilolite
Bikit et al., 2015 – Radon adsorption by zeolite
EPA (USA), 1998 – Zeolite: a versatile air-pollutant adsorber
Erdogan et al., 2008 – Ethylene adsorption on natural/modified clinoptilolites
Macala et al., 2017 – Zeolite for purification of automobile exhaust
Miner et al., 2003 – Permeable foam lagoon cover study
Pitt R., 2002 – Fate/effects of ammonia spills (case study)
Simpson D.R., 2004 – US Patent WO2005007262 A2
