Is the mechanical department of IIT (BHU) comparable to IIT-K?

Both IIT BHU as well as IITK are reputed IIT’s. 

The course curriculum at both colleges is nearly the same. In IIT BHU students can pursue courses other than academics such as Management, Foreign Languages, Finance, Personality Development as its part of BHU University. Academics at IITK is relatively tougher than IIT BHU with tough grading scheme. IIT BHU allows flexibility to its students so that they can manage both academics as well as learn extracurricular skills.  
Research culture at IITK is better than IIT BHU with more no. of research papers being published every year and more students doing Ph.D. in the College. While infrastructure and labs are equally good at both the colleges. Both IIT BHU and IITK has one of the best faculties compared to top institutions. 

Placements are roughly the same at both Colleges. IIT BHU being 100 Years old enjoys its vast alumni network due to which placement percentage is high. Students from both colleges get placed in well-known firms such as HUL, IOCL, GAIL, Maruti, Bajaj. Besides Core Engineering there are companies from other sectors like IT/Software, Consulting, Finance, Analytics, Management, etc. that offer jobs in both the Colleges. The average package of both the colleges is around 10-12 lacs CTC. 
For the course curriculum and more research work, IITK has an edge over IIT BHU for Mechanical Engineering.