This chest is located in the Hall of Souls (Court of Oryx) near the key of akka chest. If you try to open this chest you will fail because you get a lot of damage in this cave and to open the chest took a long duration.
To open the Taken Consumption you need a relic from the praying hive event in the Halls of Souls on Dreadnaught. The Pray event islocated completely random in 3 possible locations. Visit the 3 location and defeat all hive and majors at the end of the event you will get again completely random the relic. Take the relic and go to the chest location you and your fireteam have 90 seconds to reach and open the chest, otherwise you need a new relic.