Apnenica v Podutiku stoji pri Vodnikovem kamnolomu. Na čelni steni objekta je vpisana letnica 1875, vendar so tod domnevno kuhali apno že nekaj let prej.
Kako so žgali apno? V apnenico so naložili apnenčasto kamenje (kalcijev karbonat), spodaj so jo kurili z drvmi, na vrhu pa je bila plast ilovice. Kuhanje apna (pri temperaturi 1000 stopinj Celzija) je trajalo pet do šest dni, le prvič, spomladi, je potrebovala do sedem dni. Tako so pridobili živo apno (kalcijevega oksida).
V apnenico so spravili od 50 do 60 ton kamenja, ki je dalo 25 do 30 ton apna. Za enkratno kuhanje je bilo potrebnih okoli 70 kubičnih metrov drv, nekaj apnenic so skuhali celo s premogom. Apno so navadno kuhali priložnostno, ko so čistili gozdove in je bilo moč dobiti zadosti drv. Na leto so običajno pripravili po pet apnenic.
Največ dela so imeli po ljubljanskem potresu ob koncu 19. stoletja, ko so pozidavali Ljubljano in okoliške vasi. V prejšnem stoletju apnenica ni mogla več konkurirati industrijskim pridelovalcem apna. Zadnje apno so skuhali kmalu po drugi svetovni vojni.
(Vir: Aleš Florjanc / www.eheritage.si)
Slika / Picture: Diagram stare apnenice v Gibraltarju (tista v Podutiku izgleda malo drugače; boste videli). / Diagram of an old lime kiln in Gibraltar (the one in Podutik looks a bit different; you will see).
ENGLISH:
The limestone kiln (a thermally insulated chamber, a type of oven) in Podutik is located at Vodnik's quarry. The year 1875 is inscribed on the front wall of the building, but lime was allegedly cooked here several years earlier.
How did they burn lime? Limestone (calcium carbonate) was placed in the kiln, the bottom was heated with wood, and there was a layer of clay on top. Boiling lime (at a temperature of 1000 degrees Celsius) took five to six days, only the first time, in the spring, it took up to seven days. This is how quicklime (calcium oxide) was obtained.
From 50 to 60 tons of stones were brought into the kiln, which yielded 25 to 30 tons of lime. About 70 cubic meters of firewood were needed for a single cooking, and some limestones were even cooked with coal. Lime was usually cooked on occasion, when forests were cleared and enough firewood was available. They usually prepared five cookings per year.
They had the most work after the Ljubljana earthquake at the end of the 19th century, when there was a lot of construction going on in Ljubljana and the surrounding villages. In the last century, limestone could no longer compete with industrial lime producers. The last quicklime was produced shortly after World War II.