Minamata Convention-Mercury Contamination & Zinc Production

[PUSHKAR RAJ CHANDNA]

The Minamata Convention, as the treaty will be known after it is signed by the agreeing countries formally, will set rules limiting the supply of and trade in mercury and the use of mercury in products and industrial processes. It will also lay down measures to reduce emissions from artisanal and small-scale gold mining, as also from power plants and zinc metals production facilities (Zinc Smelter, Hindustan Zinc Limited). http://ning.it/14MEbng

[PUSHKAR RAJ CHANDNA]

Mercury contamination/poisoning is an issue - whether it is due to various industries around Mumbai or by primary zinc metal producer's whose audacity to contaminate our complete food chain..by contaminating the sulphuric acid produced at their plants, which is used for manufacture of fertilizers....The Minamata video…substantiate and educates all of us and make us aware of the ill effects on human beings...and is an eye opener... more and more information... need to be put on the public domain...to make all of us aware about it...so an informed decisions can be taken and policies can be framed to steer a control... 

[GOPI KANTA GHOSH]

We may discuss on Japan but our first priority to save Mumbai since Kalu river reports Mercury contamination due to industrial pollution. Milk, fish and grass reports mercury presence.

[PUSHKAR RAJ CHANDNA]

Mercury Poisoning- The Minamata Story http://www.youtube.com/watch?v=ihFkyPv1jtU 

[PUSHKAR RAJ CHANDNA]

About 90% of world’s total zinc output is produced from zinc sulphide concentrates through conventional hydro-metallurgical route i.e. Roast – Leach – Electro-win (RLE) process.

These zinc sulphide concentrates invariably contain varying amounts of mercury. [Pls. refer click: http://www.slideshare.net/prchandna/zinc-smelter-concept-note page 19]

The pre-requisite condition of zinc metal extraction from sulphide concentrate through a hydro-metallurgical process route is the elimination of its sulphur content in order to make it amenable to further treatment by leaching and then electro-winning processes.

This is predominately accomplished by roasting of zinc sulphide concentrates in fluid bed roasters and the fixation of SO₂ bearing off – gases thus generated as sulphuric acid by double contact process.

1 (One) tonne of Zinc metal co-produces approximately 1.8 (One point eight) tonnes of Sulphuric acid. [Please refer click:  http://www.slideshare.net/prchandna/zinc-smelter-concept-note page 18].

The present zinc production capacities in India have grown in geometric proportion to One million tonnes per annum in the past one decade.

The bye-product Sulphuric Acid thus produced at zinc smelters are utilized to produce phosphoric acids, which is further used for production of various types of fertilizers.

During roasting operations at 1000-1100 °C, almost all the mercury contents of the zinc sulphide concentrate fed to roasters gets volatilized and carried along with the SO₂ bearing off-gases, which is further converted to Sulphuric Acid manufacture.

Unless, the well proven technologies, which are already available worldwide, are installed and operated religiously by the Zinc metallurgical industries in the country, all the mercury metal is compulsorily entering into fertilizers and being served to us on our plates starting every day morning at breakfast till at dinner, subjecting all of us to mercury poisoning – a well-known disease ‘MINAMATA’.

 

 

[Dr. Ashok Kundapur]

Has Coal based thermal power plant included in the list ?

[PUSHKAR RAJ CHANDNA]

Please read Containerization as contamination...

Typography mistake is regretted.

Regards

P R Chandna