<p>A process for the manufacturing of formaldehyde wherein the formaldehyde is manufactured in a reactor and wherein exothermic energy is a result of the process. The reactor is pressurised through means of a compressor and that the exothermic energy from the process is used for feeding energy to the compressor, hereby, allowing increase in pressure in the reactor with a minimum of required power input from external source. The invention also relates to a apparatus for manufacturing formaldehyde wherein the formaldehyde is manufactured in a reactor and wherein exothermic energy is a result of the process. The reactor is pressurised through means of a compressor and that the exothermic energy from the process is used for feeding energy to the compressor, hereby allowing increase in pressure in the reactor with a minimum of required power input from external source.</p>
