Ring kilns. Not in use any more in the U.S. I think the Chinese probably still use them. Modern continuous kilns are much more efficient but the concept is the same. Instead of moving the fire, modern kilns move the brick.
The Chinese are currently in a program (since the late 1990's) to discourage clay brick as a wall material for ecological, environmental and land use standpoint. It has been going for a few years, but it will still continue for a longer period because of the use and dependence on clay brick. Generally, concrete products are the "approved" wall materials now. Wood is not acceptable for many durability, economic and environmental reasons.
The time involved is because of the change in design and construction since many cities in China traditionally used more brick than the entire U.S. in a year. The ecological, environment and land use is even more monumental than the volume of brick used.
Check out Vertical Shaft Brick Kilns. The most efficient kiln.
It is a similar idea to continuous Hoffman kiln but on a small scale that is an upcoming technology in China and Asia. A small operator can currently afford to build this , but they cant afford a Hoffman Kiln.
I can't put a link yet but now i notice towards the bottom of the given link is an example. the heading is "climbing kiln"
On our small brick kiln, i figure if i can change to this method my efficiency will increase by 30-40% and production will be faster.
The real Chinese problem is not the the brick themselves, but ecology and environmental. They use 500,000,000,000 brick per year, which is 500 brick for every man, woman and child, so the changeover will take time.
Due to the geology and geography, the cities are usually near a river; the good soil for food is along the rivers and the clay is under the good soil. The top soil is stripped and the clay is stripped down as far as the the decent clay is. When the shallow clay deposit is delpeted, there is no soil left to fill the excavation, so it can easily fill with water when abandoned. The wasteful use of valuable land, couple with the energy required to fire brick and the couples with the poor coal fuel quality lead to plants being shut down and the contractors build concrete products plants.
Concrete and concrete products were seleceted as the "preferred" wall laterials since they do not come from a horizontal land source and aggregates can be found in rivers (dredging) or in quarries and China has an abundance of rock and mountains. Cement can be made in efficient modern plant and economically be shipped by rail or water. The energy cost of concrete is much lower, the pollution much less and land use is minimal in a country that has very high land value and demand in the cities.
Because of the type of construction and durabillity, wood not an option, since China imports wood from the U.S., Russia and SE Asia for their small wood requirements. More buicks are sold in China than in the U.S. and Buick is 3rd in sales well behind Mercedes and BMW. This is spite of China being the worlds largest car market and being the largest vehicle manufacturing production.
Contractor Talk - Professional Construction and Remodeling Forum
A forum community dedicated to professional construction and remodeling contractors. Come join the discussion about the industry, trades, safety, projects, finishing, tools, machinery, styles, scales, reviews, accessories, classifieds, and more!