At first, Diesel also tried to use pulverized coal as fuel and designed a pulverized coal compression-ignition internal combustion engine, which was patented in 1892. However, this internal combustion engine was not successful in actual operation. After experiments, it was found that it is very difficult to use compression ignition method to realize pulverized coal fuel. So, he gave up pulverized coal and switched to diesel as fuel for internal combustion engines.