are typically fired by natural gas or sawdust; periodic kilns, coal.
During the days and nights lasting firing of the long tunnel kilns
, he also experienced the humility of the potter in the face of a kiln which, once stoked, fires stoneware vessels to 1300[degrees]C in a process beyond the reach of the human will.
Upgrades can run into the tens of thousands of dollars, if not much more, while cleaner, industrial-scale Hoffman or tunnel kilns can cost millions.
Indeed, the Chinese and Vietnamese governments, both deeply involved in their respective building sectors, strongly promoted the use of tunnel kilns for brick firing.
Costing up to US$45,000, zigzag modifications have a payback time of 1-3 years, and offer an alternative to the much more expensive Hoffman and tunnel kilns.
2 million this winter modernising and slightly extending the older of two tunnel kilns
at its Kingsbury factory, near Tamworth.
Jobs predominantly paid on this basis included unloaders of tunnel kilns
, brick sorters, die pressers, and kiln setters and drawers.
These tunnel kilns
, or anagama, were relatively inefficient, consuming vast amounts of wood and requiring days of firing to completely fuse the clay body.