Nachni Roaster

Problem Statement:- At Taleghar Village, Bhimashankar, Shahid Rajguru Svayansevi Sanstha is making Ragi laddoos. To make the laddoos, they have to roast the ragi flour continuously. To roast the flour, Manpower is a very big need. Also the safety is very important in this procedure.

Objective:- We need to provide solution in term of automation for roasting the ragi with even heat distribution.

Komal Pund, who is a DIC intern working with me on this project.

Her project blog link:-

About Project

In these links, she has explained the whole process and trials taken. As per the discussion with Ranjeet Sir, I also discussed this project with Anil Gosavi Sir, who has suggested some designs and models. And here is what I contributed in this project:-

I proposed this design:-

We made a prototype for this design and we have taken some trials as per discussion with Anil Sir.

First Prototype:-

Trials have taken on this prototype:-

First trial:-

Heat distribution media – LPG

In the first trial took 100gm of flour.

In the utensil 20gm of ghee was added, after melting ghee added flour.

Problem during trial

1. Due to some clearance between blade and bottom, the layer of flour remained at the bottom hence flour was burnt.

2. Some pieces of flour were not scrapped.

Remedies:

To minimize the clearance between the blade and bottom, aluminum foil was filmed.

Trial video is here:-

Second trial:-
Because of LPG is a heating media the flour was get burned. So we decided to take a trial on different heating media. We made one jet burner which will distribute equal heat. We used Biogas as heating media for the Jet burner.

Jet Burner:-

Jet Burner Trial Video:-

Third trial:-

A] first trial on kandi coal:-

After testing trial on jet burner we changed heat distribution media and used Kandi Coal as heat distribution media.

Heat distribution media: Kandi coal

Added 20 gm of dalda and after melting added 100gm flour and remaining dalda during binding of laddoo.

Problem solved :

The burning of flour was minimized.

Problems:

1. Pieces of flour and ghee mixture were not mixing properly.

The trial video is here:-

B] second trial on kandi coal:-

Heat distribution media – kandi coal

100gm flour and 40gm of melted dalda were added dropwise.

Problem:- Pieces of flour and ghee mixture was not scrapped properly.

The trial video is here:-

c] Third trial:-

Heat distribution media: kandi coal

Added 40 gm of dalda and then 100 gm of flour.

Problems: Flour was stuck to on vessel during roasting.

Trial video:-

d] fourth trial on kandi coal:-

Heat distribution media: kandi coal

Added 60 gm of dalda and then 100 gm of flour.

Problems: Flour was burnt because of the large amount ghee was added during roasting.

Trial Video is here:-

e] fifth trial on Kandi coal:-

Heat distribution media: Kandi coal

Added 40 gm of dalda and then 100 gm of flour.

Problems: Heat distribution and mixing problem is solved but scrapping problem is not solved properly

Trial Video is here:-

After this trial, we meet Mr. Dasturkar which is mentoring in the Vigyan Ashram on various projects. They are working in Praj Foundation. He has many years of experience in Stirrer design. They suggested again new stirrer design which was wood scrapping. And also suggested the use of indirect heating. So again made a new prototype of stirrer which is working on Kadhai based model.

Second Prototype:-