Here losses due to diffusion were minimal, however this reactor still retained
external heating.
Having found a solution to ‘hydrogen attack’, Bosch now had to address
the difficulties of the buckling and cracking arising from the external heating.
Internal heating with electricity was immediately discounted because of the
unavoidable losses to prevent overheating of the jacket. Gas heating provided
a more controllable solution
9 whereby hydrogen was burned with admitted
air within the reactor to raise it to operational temperature, the water formed
being seemingly harmless to the catalyst.
10 By the end of 1911, internal
heating had been added to the twin tube reactors which by now had reached a
length of 4 m and a diameter of 15 cm. Shortly afterwards a further innovation was added which reduced the ‘hydrogen attack’ on the convertor’s
jacket. This was achieved by continually flushing the space between the lining
and the jacket with nitrogen—harmless to the metal. The nitrogen also
reduced the pressure difference between the inner and outer parts of the lining
tube alleviating the tendency to buckle.
The influence of the improved technology on the stability of the industrial
pilot process was reflected in the steadily rising ammonia output during 1911.
The first two weeks of 1911 saw production achieve around 18 kg day
−1 . By
July 1911 a daily rate of 100 kg ammonia was surpassed. By the end of 1911
—and now with twin tube reactors and internal heating—the yearly output
was around 11 tonnes, with a daily average of 30 kg. Even by April 1911, the
BASF realised that progress was sufficiently advanced to begin planning for a
full-scale plant operating at 10 tonnes of ammonia day
−1
, although at the
time, the pilot plant was yielding less than 0.1 tonne. By the time a decision
to go ahead with a new plant was eventually made in November 1911, its
anticipated daily production had increased to 30 tonnes fixed nitrogen day
−1
,
with 70% of that destined for the production of ammonium sulfate fertiliser.
11 The speed of development after the original Haber - Le Rossignol
demonstration in July 1909 was therefore truly spectacular.
12
11.4 Of Compressors and Valves
During this time there were also more peripheral, but no less taxing problems
to be addressed, such as the design of the circulation/compression pumps, and
the valves. Initially the high-pressure compressors were a great source of
worry. Contemporary systems were designed to compress or circulate air, for
such as locomotives in mines and the Linde process. Little attention had been
paid to the ‘stuffing boxes’,
13 and leaks could be tolerated. But in high
218
D. Sheppard
external heating.
Having found a solution to ‘hydrogen attack’, Bosch now had to address
the difficulties of the buckling and cracking arising from the external heating.
Internal heating with electricity was immediately discounted because of the
unavoidable losses to prevent overheating of the jacket. Gas heating provided
a more controllable solution
9 whereby hydrogen was burned with admitted
air within the reactor to raise it to operational temperature, the water formed
being seemingly harmless to the catalyst.
10 By the end of 1911, internal
heating had been added to the twin tube reactors which by now had reached a
length of 4 m and a diameter of 15 cm. Shortly afterwards a further innovation was added which reduced the ‘hydrogen attack’ on the convertor’s
jacket. This was achieved by continually flushing the space between the lining
and the jacket with nitrogen—harmless to the metal. The nitrogen also
reduced the pressure difference between the inner and outer parts of the lining
tube alleviating the tendency to buckle.
The influence of the improved technology on the stability of the industrial
pilot process was reflected in the steadily rising ammonia output during 1911.
The first two weeks of 1911 saw production achieve around 18 kg day
−1 . By
July 1911 a daily rate of 100 kg ammonia was surpassed. By the end of 1911
—and now with twin tube reactors and internal heating—the yearly output
was around 11 tonnes, with a daily average of 30 kg. Even by April 1911, the
BASF realised that progress was sufficiently advanced to begin planning for a
full-scale plant operating at 10 tonnes of ammonia day
−1
, although at the
time, the pilot plant was yielding less than 0.1 tonne. By the time a decision
to go ahead with a new plant was eventually made in November 1911, its
anticipated daily production had increased to 30 tonnes fixed nitrogen day
−1
,
with 70% of that destined for the production of ammonium sulfate fertiliser.
11 The speed of development after the original Haber - Le Rossignol
demonstration in July 1909 was therefore truly spectacular.
12
11.4 Of Compressors and Valves
During this time there were also more peripheral, but no less taxing problems
to be addressed, such as the design of the circulation/compression pumps, and
the valves. Initially the high-pressure compressors were a great source of
worry. Contemporary systems were designed to compress or circulate air, for
such as locomotives in mines and the Linde process. Little attention had been
paid to the ‘stuffing boxes’,
13 and leaks could be tolerated. But in high
218
D. Sheppard