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US2000181A
|
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Separation of powdered or granular material, especially coal
|
|
GB370564A
|
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Improvements in and relating to the separation of carbonaceous materials, especiallycoal
|
|
GB367482A
|
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Improvements in and relating to the separation of powdered or granular material, especially coal
|
|
GB361906A
|
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Improvements in and relating to the washing and draining of coal or other minerals
|
|
US1989937A
|
|
Cleaning of carbonaceous materials
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GB341863A
|
|
Improvements in the cleaning of carbonaceous materials
|
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GB325031A
|
|
Improvements in the cleaning of carbonaceous materials
|
|
CA330003A
|
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Coal washing and draining method
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