The Census records don't show him as a miller, although the marriage record has his occupation as a baker:-
Henry Twell married Susan(nah) Heads at Moulton on 28 Dec 1836.
http://www.freereg.org.uk/search_records/5510ac34e9379002719f40f4?search_id=57553c6ff4040b130f0002da1851
Henry Twell 35 Farmer b Pinchbeck
Susan Twell 38 Farmer's Wife b Moulton
William Twell Son 13 Scholar b Pinchbeck
George Twell Son 8 Scholar b Moulton
Millicent Twell Daughter Scholar b Moulton
Ann Twell Daughter 4 b Moulton
Harriett Twell Daughter 0 b Great Gonerby
Frances Twell Mother Widow 74 Visitor b Surfleet
1861
Henry Twell Head 45 Farmer 46 Acres 1 Man b Pinchbeck
Susannah Twell Wife 48 Farmers Wife b Moulton
George K Twell Son 17 1844 Farmers Son b Moulton
Millicent Twell Daughter 15 1846 b Moulton
Harriett Twell Daughter 10 1851 Scholar b Moulton
Emily Twell Daughter 7 1854 Scholar b Moulton
1871
Henry Twell Head 55 Parish Officer and Land Owner b Pinchbeck
Susan Twell Wife 50 b Moulton
George H Twell Son 27 Farmer of 56 Acres 2 Labourers b Moulton
Hariet Twell Daughter 20 Grocer and Draper b Great Gonerby
Emily Twell Daughter 17 Dairy Maid b Moulton
1881 - Boston
Henry Twell Head 65 Retired Farmer b Pinchbeck
Sus Twell Wife 68 b Moulton
Millicent Twell Grand Daughter 13 Scholar b Moulton
David