This code executes, though I don't know what it is that you want.
Dim blockingCollection As BlockingCollection(Of String) = New BlockingCollection(Of String)
Dim count As Integer = 0
Task.Factory.StartNew(Sub()
While True
blockingCollection.Add("value" & count.ToString)
count = count + 1
End While
End Sub)
Task.Factory.StartNew(Sub()
For Each value As String In blockingCollection.GetConsumingEnumerable()
Debug.WriteLine("Worker 1: " & value)
Next
End Sub)