CASHEW HUSK FOR ANIMAL FEED, BIOENERGY AND FUEL, NATURAL DYES AND TANNINS, COMPOST AND ORGANIC FERTILIZER

CASHEW HUSK/ TESTA

Specifications:

Protein: 11.95

Moisture: 10

Fat: 11.8

Crude Fiber: 7.14

Packing: in 25kgs PP bag

Origin: Vietnam

APPLICATIONS

1. Bioenergy and Fuel

1. Briquettes and pellets: Cashew husk is compressed into high-energy briquettes for domestic and industrial fuel. Calorific value ≈ 18–22 MJ/kg.
2. Biogas production: Used as feedstock in anaerobic digestion (often co-digested with cashew apple waste).
3. Biochar: Pyrolyzed to produce biochar for soil amendment and carbon sequestration.

2. Animal Feed

1. After proper detoxification (boiling or fermentation to reduce tannin content), husk can be used as a low-cost ruminant feed (cattle, goats) – up to 10–20% of ration.
2. Silage: Mixed with molasses or other materials for cattle feed in some African countries.

3. Activated Carbon Production

1. Cashew nut shell (testa) and sometimes husk are carbonized and activated to produce low-cost activated carbon used for water purification, gold recovery, and air filters.

4. Natural Dyes and Tannins

1. Rich in tannins (10–25%); used as natural brown dye for textiles and leather.
2. Source of natural tanning agents in eco-friendly leather processing.

5. Mushroom Cultivation Substrate

1. Cashew husk mixed with sawdust or rice bran is used as a low-cost substrate for oyster mushrooms (Pleurotus spp.) in India and Africa.

6. Compost and Organic Fertilizer

1. Decomposes relatively fast and adds organic matter and potassium to soil.
2. Vermicomposting with cashew husk is practiced commercially in some areas.

7. Particleboard and Medium-Density Fiberboard (MDF)

1. Husk fibers are mixed with urea-formaldehyde or natural binders to produce low-cost particleboards for furniture and construction.

8. Pharmaceutical and Nutraceutical Extracts

1. Contains phenolic compounds, flavonoids, and antioxidants.
2. Extracts studied for anti-diabetic, anti-inflammatory, and antimicrobial properties.

9. Absorbent for Oil Spills and Heavy Metals

1. Raw or modified cashew husk is an effective biosorbent for removing oils, dyes, and heavy metals (Cr, Pb, Cd) from wastewater.

10. Traditional and Local Uses

1. In parts of India (Goa, Kerala) and Africa: dried husk used as fuel in cashew nut roasting.
2. Traditional medicine: decoctions used for diarrhea and skin infections (due to astringent tannins).

11. Emerging/Research Applications

1. Nanocellulose extraction for biodegradable packaging.
2. Precursor for graphene and carbon nanotubes.
3. Source of anacardic acids (similar to cashew nut shell liquid but in lower concentration).