India and Brazil are the major cashew exporters, with 60 per cent and 31 per cent, respectively, of the world market share. The cashew comprises 32.5% nut and 67.5% shell. The nut is edible, but the shell remains the waste product of the cashew processing industry. The shell undergoes further processing to extract cashew nut shell liquid, and the residue is called Cashew Deoiled Cake.

What’s Inside the Cashew Shell?

The shell undergoes processing to yield Cashew Nutshell liquid (CNSL) and Cashew Deoiled cake (DOC). The Cashew nut shell contains 15-25% dark reddish-brown viscous liquid called CNSL. CNSL is a mixture of 70% anacardic acid (a salicylic acid analogue and a potent skin irritant) with 18% cardol and 5% cardanol. The two latter components are phenolic substances used for epoxy resins, varnishes, and many high-tech materials.

Cashew Shell, CNSL and DOC have a gross calorific value of 5600 Kcal/Kg, 8000 Kcal/Kg and 4500 Kcal/kg, respectively. Despite their high calorific value, why can’t we use them as a fuel for industries? Let us understand in this blog.

What’s wrong with these byproducts?

So, what happens when the DOC and the CNSL combustion occurs? Here are some reasons for that:

1. Cashew Shell contains high carbon content. When burnt alone, it produces black smoke.
2. All three byproducts contain a high amount of phenol, thus affecting the furnace’s refractory linings.
3. These byproducts contain a high amount of anacardic acid. Therefore, direct combustion could affect the system’s safety and generate toxic fumes.
4. CNSL is acidic, so handling DOC becomes difficult for the operating team. The workers have reported itching/burning sensation in the hands and skin peeling off with consistent exposure.

What change did Steamax bring?

We recommend against using DOC as a standalone fuel in any equipment. Considering these issues, we have come up with a new fuel, “Astillas”, which has cashew DOC as one of the raw materials, but they are processed to reduce the CNSL content as well as the toxicity of the fuel.

1. The Astillas have a CNSL oil content of below 5% compared to 10-20% in DOC.
2. Reducing the oil content reduces the carbon content as well. Therefore, black smoke emissions eliminate with this.
3. Astillas have a high calorific value (>4200 kcal/Kg), low ash(<2%) and moisture content (<10%).
4. Using Astillas also reduces CO2 emissions compared with wood logs, coal, petcoke and diesel.
5. Astillas come in reusable bags that are easier to store and handle. The bags are specifically designed for longer life to ensure re-usability.

Our customers include Hindustan Unilever, Varun beverages, Coca-Cola, Britannia, Varun beverages, Calderys, MMG Healthcare, etc. We supply 5000+ Ton fuel per Month Pan India. If you wish to enquire more about our fuel “Astillas”, click HERE. Feel free to connect with us anytime at – info@steamaxindia.com or +91-9315124803.