The How and Why Air Attacks Crippled the German Oil-Chemical Industry

Natural Oil Targets

Approximately 25 percent of Germany's wartime oil was supplied by 40 refineries, 25 of which were located in prewar Germany (Figure 80). Seventeen of these, accounting for 82,500 tons per month or 48 percent of the total available crude, were grouped in northwestern Germany. The crude oil refined monthly totaled 170,000 tons, of which 38 percent came from prewar Germany, 59 percent from Austria, and the remainder from "protected" countries. The products included most of Germany's highly important airplane engine lubricants, motor oil, industrial oils, and some diesel fuels.

Figure 80, Key

Refining Capacity In Greater Germany And Protectorate

Includes Rerunning Plants. Total Crude Distillation Capacities (excluding Poland-Galician area),

3,000,000 Tons per Year

No.CompanyLocationTons per Month
Old Germany
26Rhenania (Shell).Harburg (Hamburg)60,000
27Rhenania (Shell)Grasbrook (Hamburg)17,000
28Rhenania (Shell)Wilhelmsburg (Hamburg)8,350
29Rhenania (Shell)Monhein16,000
30Deutsche Erdoel A.G.Wilhelmsburg10,000
31Deutsche Erdoel A.G.Heide16,000
32, 33Deurag-NeragMisburg27,000
36Deutsche GasolinEmmerich6,000
37Deutsche GasolinDollbergen4,200

38Mineraloel and Asphalt A.G.Ostermoor10,000
39Oelwerke J. SchindlerHamburg2,500
40Oelwerke J. SchindlerPeine1,500
41EbanoHarburg (Hamburg)45,000

43Vacuum Oel A.G.Oslebshausen10,000
44Vacuum Oel A.G.Wedel2,500
46Ernst Schliemann's OelwerkeHamburg5,000
47Albrecht and Co. MineraloelwerkeHamburg1,250



Vienna Area
49Shell-FloridsdorWien-Floridsdorf 13,000
50Vacuum OelA.G. Kagran (Wien)9,000
51Dea-NoyaSchwechat (Wien)15,000
53Deutsche GasolinKorneuburg7,000
55OstmarkischeMineraloelwerkeLobau (Wien)25,000
Protectorate Czech Area
57Oderfurter MineraloelwerkeOderfurt6,000
58Vacuum Oel A.G.Kolin12,500
61KralupyKralupy (Prague)1,599
62Privos (Moravska Ostrava)

Poland-Galician Area
63Kontinentale OelTrzebinia22,500
64Vacuum Oel A.G.Dzieditz8,500

Five refineries inDrohobycz28,500

Synthetic Fuel Production In Greater Germany

No. PlantTons* per Month
Fischer-Tropsch Synthesis
1, 21Essener Steinkohle7,080
* Installed capacity at end of war.

Production of lubricants, always bordering on inadequacy, had become critical by August, 1943. The German air forces had increased their demands for airplance engine oil from 62,000 to 87,000 tons per year, an increase of 51 percent over production for July. The loss of the Naples and Leghorn refineries increased Italy's demands on Germany from 7,000 to 30,000 tons per year. Various makeshift measures were imposed on industrial users. It is known that synthetic oil plant compressors were oiled with water-oil emulsion and that the reclamation of used oil was widely practiced. Plans were made to increase the processing of crude in Austria and southwestern Germany with French and Italian equipment, and to accelerate completion of several synthetic lubricating oil plants. Table 32 lists Germany's 1944 production of principal refinery products.

Table 32

German Oil Refinery Production of Finished Products

(Metric Tons)

1944AviationMotorSolventsKeroseneDiesel OilFuel OilLubricantsTotal
Jan. 1945

Survey of Refineries. Oil Division Teams made detailed examinations of six plants representing 35 percent of the oil refining production during the first four months of 1944 (see Appendix Tables E1, E2). Three additional plants and several dispersal plants were given part-scale investigation. Five of the refineries studied were modern in design and produced a total of 10,248 tons per month, equal to 55 percent of the motor and aviation oils or 80 percent of the aviation grade lubricating oil (see Figure 81).
Process Description. In contrast to synthetic oil plants, refineries are not aggregations of processes organized in standardized arrangements. They are equipped according to the amounts and composition of the crude oil to be run and the products to be made. A refinery is usually simple in design and occupies about one eighth of the area covered by a synthetic plant of the same capacity. An average-size refinery produces about 40,000 tons per month. It occupies about 100 acres of which 13 are devoted to tanks, 9 to process equipment, 4 to utilities and general buildings, and the remaineder to fire lanes, roadways and space for expansion (Figure 82).

In Germany, where the most needed product was lubricants, the crude oil was first distilled in a pipe or shell still to remove volatile materials such as gasoline, kerosene, and diesel oils. The remaining liquid, containing crude lubricating oils of various types, was further distilled under vacuum to prevent thermal decomposition. These oils were then subjected to refining operations for removing impurities, increasing temperature stability, improving color, and removing wax. These steps involved complicated equipment, and it was not unusual for finished lubricating oil to pass through as many as six treatments after being separate from the volatile materials. For the manufacture of gasoline, equipment was employed for cracking, removing odor, improving color, eliminating corrosiveness, and blending, or for the addition of tetraethyl lead and inhibitors.

Right - Figure 83. Ineffective bombing of process equipment. This atmospheric distillation unit are of 2 acres in the Deurag-Neurag refinery received ten 500-lb and thrity-three 250-lb bomb hits. Vital equipment was not permanently damaged. It took eight days of repair time to restore the unit to 100 percent of original capacity.

Vulnerability. The crude oil distillation and cracking units which comprise the principal equipment of a refinery are usually of open frame and rugged construction, with cast iron or steel walls 1 to 2 in. thick. Consequently, they are difficult to damage, except by direct hits from fairly heavy bombs (see Figure 83). The steam generating equipment is also solid in construction and there were very few German refinery power houses knocked out by bombs.

The most vulnerable installations were found to be the solvent dewaxing; and gasoline chemical treating plants. These units were of light construction, and large amounts of highly inflammable liquids were handled or stored in the immediate area. Storage tanks were also a vulnerable target, but investigation revealed that the Germans were operating out of and into railway tank can with only slight inconvenience after 80 percent of their tankage had been destroyed. A weak spot in every refinery is its cooling water system, since fairly large quantities of low-pressure water are circulated for condensing vapors and cooling the oils. The water coolers are fragile. and susceptible, to blast damage, while the water circulating pumps generally are of brittle cast-iron construction and are grouped in one place. One or two bombs accurately placed could stop all operations until these pumps were replaced.

Air Attacks. The 1943 air attacks on Hamburg, a city which boasted 28 percent of the refining production, caused tremendous destruction but failed to damage the highly essential refineries. In fact, lubricant refining continued at an uninterrupted pace. In May, 1944, when the oil industry was finally assigned a top priority, refineries were still producing lubricants at approximately their normal capacity. Between May, 1944, and V-E Day, the Allied air forces dropped 45,098 tons of high-explosive bombs at the German refineries. These attacks proved vastly more damaging than had been anticipated in that, although the crude distillation equipment remained virtually intact, the lubricant manufacturing facilities were practically destroyed and the resulting situation was as serious for Germany as though all the equipment had been damaged (Figures 84, 85, 86). After the synthetic oil plants were bombed out, it was possible to prepare some 43,000 tons per month of diesel oil in the refineries and dispersal plants. About 22,000 tons came from refineries, which meant that they still retained about 60 percent of crude distillation capacity.

Damage. The damage encountered in most of the refineries examined was of the reparable type. Practically every attack which hit a refinery target target stopped operations for a time, but the damage was such that it could usually be repaired within a few weeks with materials available. In some instances, vulnerable solvent dewaxing plants and similar units were destroyed by bombs or fire, and the lubricant section was out of operation for months. Permanent damage to compressors, pumps, and large engines would have deprived the enemy of vital production, but unfortunately this occurred all too seldom. The Allied air forces proved their strength over Hamburg, but left the large lubricating oil refineries practically untouched. It takes a minimum of ten months to rebuild a refinery. Had at least some of the bombs dropped on Hamburg during the attacks in midsummer 1943 been diverted to Germany's three principal lubricating oil refineries, it is not difficult to assess the catastrophic results to the German war economy.

Right - Figure 94. Destruction of a small electric power plant in the Deurag-Neurag refinery by three direct hits and two near misses, of 500-lb high-explosive GP (U.S.) bombs fuzed 0.1 sec nose and 0.025 sec tail. Since the generators were destroyed, replacements would have been needed to repair the damage.
The estimated residual capacity of the nine plants surveyed was 127,500 tons or 60 percent of original capacity, after repairs which could be made in ten weeks without the replacement of any major equipment. The quality of products would not compare with the quality of those available before the start of strategic bombing, since in most cases primitive methods would, of necessity, replace the modern processes destroyed.
In all plants surveyed, only nine deaths resulted from strategic bombing.
Appendix Table G16 contains bombing accuracy data on the German refineries.

War History of a Typical Refinery

The Deurag-Nerag Refinery at Misburg, 5 miles east of Hannover on the Weser-Elbe Canal, is a typical German refinery (see Figures 87, 88, and 89). Its capacity input was 27,000 tons of crude per month, and its primary products were airplane oil and other high-quality lubricants, diesel fuel and motor gasoline (see Appendix Table E3).

Right - Figure 87. Deurag-Neurag oil refineries, Misburg, Germany. 1. Deurag crude topping unit. 2. Deurag boiler house. 3. Fullers earth plant. 4. Neurag boiler house. 5 Neurag electric power plant.

This refinery was heavily attacked on 20 June 1944 when 103 tons of bombs exploded among its installations, causing extensive damage, particularly to the vulnerable solvent dewaxing process. It closed down but restarted on 1 August at 40 percent of its original capacity for low-quality lubricants and 95 percent of its motor fuel capacity. In a second attack on 24 August, the bombing was less accurate and only 44.7 tons of bombs exploded in the refinery. The plant was back in operation again in 1 September. Another raid on 11 September, in which 54.9 tons of bombs hit the target, closed it down until 15 October. A raid on 4 November missed the refinery but hit a near-by cement factory. On 20 November, the entire refinery was again shut down, and subsequent raids prevented it from resuming operation except for eight days until the time of its capture in early April, 1945. A total of 40,000 tons of raw and finished products were lost as a result of fire and spillage, and the enemy was deprived of an estimated 260,000 tons of petroleum production up to V-E day.

Defense Measures. The Misburg refinery was equipped with the usual defenses devised for German industry. A decoy plant, approximately 2 miles from the refinery, attracted bombs during several raids. The canal near the factory was camouflaged so it could not be used for identification purposes, and camouflage matting was placed over the the tanks to change their contours. A smoke screen apparently had some effect as it was noted in several target reports. The flak was believed by the German management to be inadequate, and numerous requests were made for additional and heavier guns. Shelter accomodations for the plant personnel included two reinforced concrete cylindrical shelters 60 feet long, with walls that were as much as 6 ft thick. Small one-man shelters were also used extensively to ennable key personnel and machine operators to remain at their posts during air raids. Fire-fighting equipment was modern and effective. Stationary foam systems were provided at the beginning of the war, but they were easily damaged by bombs and were soon discarded for portable foam equipment. High-pressure water spray was also used extensively. The plant showed remarkably little fire damage. This is due partly to the efficient fire fighting and partly to the energy of plant personnel in dealing with incendiaries, which they declare did not terrify them and could be easily extinguished.

Above - Figure 88. Deurag-Neurag oil refineries, Misburg before bombing.

Above - Figure 89. Deurag-Neurag oil refineries, Misburg, after bombing.

Left - Figure 90. A direct hit by a 500-lb bomb opened up the heat exchangers of this crude topping unit, an extremely vulnerable spot in the Rhenania-Harburg refinery. Repairs were completed in six weeks.

Personnel. The refinery employed 1,060 people, including 795 Germans and 265 foreigners. Absenteeism remained low and was never a contributing factor toward production losses. Morale, on the other hand, deteriorated badly after the spring of 1944, and the plant reports cerain estimates of as much as 50 percent drop in efficiency by the end of 1944. The nervous strain of long hours plus close government supervision apparently had its effect on management and labor. There is evidence that, during the final months of the war, an organized "go slow" campaign was carried on in the refinery. During the autumn of 1944, the management found it necessary to place additional supervisory guards over forced repair labor in order to get essential jobs done.

Impressions and Recommendations. The accuracy, in bombing attacks on this refinery was below the average. Out of 5,747 tons of high explosive bombs dropped, 290.2 tons actually hit within the refinery area, an accuracy of 5 percent. The average bomb weight for all the raids was 487 lb. A memorandum of a meeting at the refinery between the plant directors, Luftwaffe officers, and government repair officials contained this statement: "It is thought that greater damage could have been attained by half the planes and half the weight of bombs if larger bombs had been employed." Because of the reparable nature of the damage inflicted, the refinery maintained a high rate of recuperability. In May, 1945, this plant was able, under Allied control, to produce 18,000 tons per month or 65 percent of capacity after eight days of repair. Within 40 days, the production was up to 100 percent of original capacity. The products were of lower quality, however, since the modern lubricating oil units had been destroyed. The timing of the raids was good, except in a single instance when the plant was allowed one month of uninterrupted production.

Right - Figure 91. A direct hit on this vulnerable process equipment in the Deurag-Neurag refinery by one 500-lb GP (U.S.) bomb fuzed 0.1 sec nose and 0.025 tail caused secondary fire damage and resultant permant destruction to a solvent dewaxing plant. Fire damage was a comparatively rare occurence at refineries.

Against the equipment used in this type of refinery, it is believed that bombs of 2,000 lb and larger are most efficient. Anti-personnel bombs would prevent fire fighters from leaving shelters. Delayed action incendiaries or waves of incendiaries dropped a few minutes after high explosives would ignite flammable gases and liquids spilled from broken tanks and pipelines. Thus more extensive fire damage should result. Table 33 is an attack and damage log, including dates of attacks, bombs dropped, bombs hitting the target, production data, description of damage, and recovery capacity estimates. Figures 90 through 94 show types of damage which were found in oil refineries.

Below - Figure 92. Destruction of this small steam boiler unit in the Deurag-Neurag refinery was caused by direct hit of a 500-lb high-explosive GP (U.S.) bomb fuzed 0.1 sec nose and 0.025 sec tail. Damage caused by this attack shut down the plant for four weeks.Below - Figure 93. This tank in the Deurag-Neurag refinery, a fairly vulnerable target, withstood eight near misses of 500-lb and 250-lb high-explosive GP (U.S.) bombs fuzed short delay. A fire started, but was extinguished, and after minor repairs the tank was put back into service.

Table 33

Damage from Air Attacks on Deurag-Neurag Oil Refinery at Misburg

Attack DateTons of Bombs DroppedTons of Bombs on Target AreaDaily Production before Attack, TonsDaily Production after Attack, TonsDescription of Damage to UnitsRecuperability after the AttackEstimated Damage in RM
20 June 19444971031,430None, restart 1 AugustNerag: Top vacuum unit: tanks 70 percent damaged. Courbrough vacuum unit: pump house and tanks 90 percent damaged. Furfural unit: heavily damagedm, pump house and foundation destroyed, tanks 80 percent destroyed. Contact plant: damaged, New contact plant: furnace destroyed, pump house and tanks heavily damaged. Old dewaxing and refrigeration plant: filter and pump house destroyed, refrigeration unit and two compressors damaged. New dewaxing and refrigeration plant: two towers displaced by blast. Blending and mixing plant: 50 percent destroyed. Propane de asphalting unit: heavily damaged, tanks 100 percent destroyed, one compressor and all pumps damaged. Transfer pump house: lightly damaged. Boiler and power house: power house destroyed, treating water system and conveyor damaged.

Deurag: Topping unit: heavily damaged, tanks 80 percent destroyed. Dubbs cracking unit: damaged, tanks 50 percent destroyed. Stabilizing unit: tanks damaged. Gas polymerization unit: towers seriously damaged. Redistillation unit: damaged. Kerosene treating unit: damaged. Transformer station and power lines and piping: 80 percent destroyed. Compressed-air station, mechanical and electrical workshop: completely destroyed. Drum filling building: destroyed and pumps damaged. Tankage: 14 tanks destroyed, 5 tanks damaged, crude oil storage 70 percent destroyed. Office building, laboratory, and railroad tracks: heavily damaged.

Nerag: Coubrough unit: did not operate after this attack. Furfural unit: will operate 40 percent by 4 August. Extraction plant: dispersed to Porta. Acid treating plant: operated last in 1943. New acid treating plant: old unit rebuilt at new location, almost finished on 26 November 1944, never been in operation. Old dewaxing and refrigeration unit: will operate at 40 percent by 8 August. New dewaxing and refrigeration plant: operated only occasionally, using refrigeration unit of old dewaxing plant. Blending and mixing plant: only 50 percent repaired, never put in operation. Propane deasphalting plant: wil operate at 100 percent by 1 August. Transfer pump house: will operate by 25 July. Boiler and power house: conveyor will operate by 20 July. Transfer pump house: will operate by 17 August.

Deurag: Topping unit: will operate by 25 July. Dubbs cracking unit: will operate by 1 August. Kerosene treating unit: no feed stock to operate. Loading rack repaired by 10 August. Boiler house repaired by 20 July. Piping repaired by 28 July. Cooling tower and drum system repaired by 25 July. Drum filling building repaired by 10 August. Workshop repaired by 14 July.

24 August 194421744.71,350None, restart 1 Sep.Neurag: Furfural unit: piping and building 30 percent damaged; furnace pumps, instruments lightly damaged. Contact plant: 60 percent damaged. Extraction plant: damaged moderately, approximately 40 percent. Acid moderating plant: piping and storage drums 40 percent and building completely destroyed. Blending and mixing plant: lightly damaged. Boiler and power house: damaged

Deurag: Dubbs cracking unit: heavily damaged. Piping, fuel gas system, hot oil pump house, office building, and laboratory: heavily damaged. Loading rack, boiler house, water pump house, transformer station and power lines, and 18 tanks damaged. Tankage: 9 tanks destroyed.

Deurag and Neurag back on stream by 1 September1,000,000
11-12 September 194430654.9620None, restart 15 OctoberNerag: Top vacuum unit: furfural unit and contact plant: heavily damaged. Propane deasphalting unit: medium damage. New dewaxing and refrigeration plant, boiler and power house: lightly damaged.

Deurag: Dubbs cracking unit, piping, cooling tower and system, transformer station and power lines: heavily damaged. Boiler house, two crude oil tanks, and laboratory: completely destroyed. Topping unit, kerosene treating plant, transfer plant, transfer pumps, loading racks: damaged.

Deurag and Neurag back on stream by 15 October2,000,000
20 November 1944No record3.51,150None, restart 23 DecemberNerag: Furfural unit: damaged.

Deurag: Stabilization topped gasoline stabilizer and piping: heavily damaged. Loading rack damaged.

Deurag and Neurag back on stream by 23 December500,000
26 November 194489226.20None, restart 23 DecemberNerag: Furfural unit, old dewaxing and refrigeration plant, new dewaxing and refrigeration plant, propane deasphalting unit: light damage.

Deurag: Topping unit, piping, transformer stations and power lines, railroad tracks: heavily damaged. Tankage: 5 tanks destroyed and 10 tanks damaged. Stabilization unit, gas polymerization unit and loading rack: damaged.

Deurag and Neurag back on stream by 23 December3,000,000
29 November 19441,1601.20None, restart 23 DecemberDeurag: Stabilizing unit, gas polymerization unit and loading rack: damaged.Deurag and Neurag back on stream by 23 December1,000,000
31 December 194423329.5470Restart 14 FebruaryNerag: Furfural unit, acid treating plant, blending and mixing plant, boiler and power house: heavily damaged. Top vacuum unit, contact plant, new contact plant, old dewaxing and refrigeration plant, new dewaxing and refrigeration plant, propane deasphalting plant, transfer pump houses: damaged

Deurag: Topping unit, Dubbs cracking unit, cooling tower and system, transformer station and power lines: heavily damaged. Stablilization unit, gas polymerization, redistillation, transfer pumps, loading rack, drum filling building, office building, laboratory, and workshops: damaged

Nerag: Top vacuum unit repaired by 26 February. Furfural unit repaired by 31 March. Old and new contact plants repaired by 26 February. Propane deasphalting unit: did not operate after this attack. Transfer pump repaired by 15 January.

Deurag: Topping unit repaired by 14 February. Dubbs cracking unit repaired by 20 February. Loading rack repaired by 31 January. Piping, cooling tower repaired by 15 Febraury. Drum filling building repaired by 26 February. Workshop repaired by 20 January.

13-14 February 19453612.00None, restart 26 FebruaryNerag: Furfural unit: heavily damaged. Propane deasphalting unit: damage

Deurag: Dubbs cracking unit: damaged.

Units damaged by this attack will be repaired by 26 FebruaryNo data
15 March 19451,2337.20None, Shut downNerag: Boiler and power house: damaged

Deurag: Ethyl blending, cooling tower and system, transformer station and power lines, railroad tracks, and 8 tanks: damaged. One tank destroyed. Office and administrative building: heavily damaged.

This attack caused an indefinite shutdown7,500,000

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