Syngas - Associação Brasileira de Produtores de Florestas Plantadas

(a)Use of Gasoline in Diesel EnginesAt various times during the war the Germans experienced a serious shortage of adequate diesel fuel. Theseshortages were partly due to the necessity of concentrating production efforts upon the preparation of high-testaviation gasoline. It was necessary at these times to operate diesel engines on gasoline and gasoline blendswhich were or could be made available locally. Regardless of the type of gasoline blend used, an addition of 5percent of motor oil to the fuel was prescribed, to protect the fuel injection pumps and not to improve theignitability. There is a basic difference between diesel injection pumps, lubricated and sealed by the fuel itselfand gasoline injection pumps, used currently on aircraft engines, lubricated by a supply of motor oil. Naturallythe situation being temporary, no change over of the injection system was made. The only difficulties mentionedin connection with the use of gasoline in diesel engines were the excessive overheating of the engine and sometendency to vapor-lock in hot weather. In certain cases additives were needed to reduce the octane rating andbring the fuel more in line with a diesel fuel. Chlorpicrin was used as one of these additives. A cetane rating of35 was aimed at. It can be obtained either by fractionating properly the Fischer-Trospch gasoline, or byblending a gasoline of as high as 60 octane with a high cetane diesel fuel. Naturally low aromatic gasolinessuch as "Ruhrbenzin" were selected in preference to higher grades.An attempt was made to use benzol. Ignition was possible only by mixing ethyl nitrate vapour with the air usedof vapour was cut off. The ethyl nitrate was kept in a brass container in a water bath, as its boiling point is194°C. The vapour circuit had to be absolutely tight as ethyl nitrate vapours are toxic. Approximately .3 cubiccentimeters of nitrate was used per one liter cylinder. An attempt to spray liquid ethyl nitrate in very smallquantity into the cylinder resulted in a serious explosion.During the diesel fuel shortage of 1941-42 tests were conducted at the Leuna plant of I.G. Farben for the use ofa 50-50 mixture of diesel fuel and Leuna gasoline produced from the hydrogenation of brown coal tar, andhaving a cetane rating of 35. No difficulties were noted except a slight reduction in power in trucks andlocomotive diesels or in small construction engines. In large, slow speed diesels vapor-lock difficultiesdeveloped.