Protokoll über die Jahrestagung am 29. Dezember 1947; [ditto] 7.u.8. Januar 1948; [ditto] 5.-7- Januar 1949

Minor wear. Table-of-contents faded. Good. Oil Shale Technology [Frankfurt a/ Main] 1947-1949 orig. wrappers 29x20cm, [70] pages., THREE VOLUMES. Cover title. Mimeographed table of contents. Original single-side typescript text. At head of each cover title: "Vertraulich" ["Confidential"]. These are three volumes of original typescripts transcribing technical conferences of the Lurgi firm held in 1947 [8 pages], 1948 [9 pages] and 1949 [(53) pages, pagination running 11,14,6,4,18]. ["The Lurgi–Ruhrgas process is an above-ground coal liquefaction and shale oil extraction technology. It is classified as a hot recycled solids technology..,.The Lurgi–Ruhrgas process was originally invented in the 1940s and further developed in the 1950s for a low-temperature liquefaction of lignite (brown coal). The technology is named after its developers Lurgi Gesellschaft für Wä rmetechnik G.m.b.H. and Ruhrgas AG. Over a time, the process was used for coal processing in Japan, Germany, the United Kingdom, Argentina, and former Yugoslavia. The plant in Japan processed also cracking petroleum oils to olefins. In 1947–1949, the Lurgi–Ruhrgas process was used in Germany for shale oil production..,." - wikipedia].