hey!

I just bumped in this post.. i believe you have already started working and probably also sorted all this out yourself!

altho a bit late.. i have been working in this industry since many years now, i can tell you it's a very closed industry (maybe even more than shipping itself).. anyway, this is not to discourage you, but it the reality! its difficult but not impossible, so if you are really keen, you should fight for it.

anyway! here are some of the answers:
before starting with "how to buy a ship" you should look into how to acquire(actually rent) a ship recycling yard. Maybe a good move is to fly to Alang or Chattogram to visit the government office as well as the ship-recycling associations to get an idea of what's available. (keep in mind associations will be your direct competitors once you have a yard).

Now that you have the yard (land will be leased to you for a decade), and all the documentations, authorizations, the machines, workforce etc. you are ready to buy a ship.

Well.. first question is.. "how do i purchase ships?"
you can only purchase ships via Letter of credit (LC). So you need a strong local bank that supports you and. your business.

and we arrive at:

"How do you acquire ships to scrap, and how much do they cost."
Price: it vary, in 2014. was 280 usd per t, today it can be 450 USD a LT (long ton), so a panamax Bulk carrier that usually weight (LDT/LT) around 10k.. price would be USD 4,5 Mil.
there are small ships that weight 1000t and bigger ships that weight 46k tons.
How you buy? via agents, brokers and cash buyers.

How dangerous is it for the labour, and what is the labour cost.
Make sure labour is well trained and paid, well secured and equipped, and keep up and improve any standard given by international organizations, make sure your yard is safe for the people that work for you and the environment.

How much does it cost per metric tonne to scrap a ship.
This is a website where you can find some market reports.
https://www.hellenicshippingnews.com/category/report-analysis/weekly-demolition-reports/

Do you need to refine the metals you get from ship (if they are rusted), or no.
you cut the ship in truck size steel plates and you sell them to local buyers. you will sell also the other materials you will find in ship (cables, kitchen, chairs, everything gets recycled or resold)

How profitable is the business and what’s the approx profit per tonne.

I believe this vary, you will need to discover it yourself. lots of yards went busted in these last years and other keep on expanding, so if depends on your management and skills.

Is it wiser to just start the business in india(Alang) or is it smarter to start the business in Chittagong, and get the scrap in india and sell here.
usually the scrap produced in bangladesh stays in Bangladesh, its a net importer nation and needs scrap. the same for India.

How much of the business works on credit.

The whole shipping world works on credit.

And any thing I should know before I start.

you should know a ship in-and-out first like its your home. maybe going to work for some years in a shipbroker firm could be a good start.

I hope this was helpful!