Dear,

You can take Purvanchal Express towards Kolkata and get down at Naihati Junction. From Naihati Junction you can take the  Kalyani Simanta Local towards Kalyani Simanta and get down at Kalyani Ghoshpara. Then a walk of 23 min from station take you to kgec. The journey takes about 4 hrs by train and 3 hr by car via NH19.
Hope this helps

Hello Prabhat, KGEC is in Kalyani and is separated from Durgapur by a distance of 146 Km.

It would take you about 3 hrs to reach by Car/Bus via NH19. You can also take train to Howrah/Sealdah station and from there take a local train to Kalyani. 

Hope this helps.

What type of route do you want through train or through car

If car then go through NH 19

dugapur-gopalpur-mankar-bhardhaman-memari-kgec

if trains

sealdah sf intercity express

patna-kolkata express

sealdah-kolkata express

I hope this helps to you and maybe you shpuld know how to book train tickets