{HEAD ~ An object} of the present invention is to overcome {TAIL ~ the disadvantages} of the prior art by directly contacting a non condensible gas as a feed gas with heated water, thereby humidifying the feed gas, while utilizing the heat possessed by the formaldehyde product gas as a heat source for heating the water 
is to overcome
{ HEAD ~ An object } of the present invention is to overcome { TAIL ~ the disadvantages } of the prior art by directly contacting a non condensible gas as a feed gas with heated water , thereby humidifying the feed gas , while utilizing the heat possessed by the formaldehyde product gas as a heat source for heating the water
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH