Absorption tower for preparing ammonia water from liquid ammonia and process thereof

A spraying device and a filler area are arranged on the upper portion of the absorption tower, a tower kettle of the absorption tower is an ammonia water collecting barrel, a liquid ammonia heat exchange type evaporation device is arranged in the middle of the absorption tower, and a liquid ammonia inlet is formed in the lower portion of the liquid ammonia heat exchange type evaporation device. The liquid ammonia inlet is communicated with a shell pass of the liquid ammonia heat exchange type evaporation device, the top of the shell pass is communicated with a gas outlet pipe extending upwards, a tube pass of the liquid ammonia heat exchange type evaporation device comprises a plurality of heat exchange tubes which are vertically distributed, the tops of the heat exchange tubes are communicated with the upper part of the absorption tower, and the bottoms are communicated with the ammonia water collection barrel; through the absorption tower integrated with the liquid ammonia heat exchange type evaporation dev