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The Innovation Team at ENECH’s Synthesis Center Improves the Heat Transfer Efficiency of Water Coolers. Author/Source: ENECH. Date: July 16, 2021. Page views: 22. As the high temperatures of summer persist, production equipment—particularly water coolers that use circulating water as a heat transfer medium—is subjected to extreme heat from both inside and outside. The water cooler at the outlet of the ammonia compressor (105-J) in the ammonia synthesis unit of the synthesis plant is particularly sensitive to rises in the temperature of the circulating water; it is unable to fully cool the ammonia gas compressed by the compressor, which results in the pressure at the compressor’s outlet approaching the level at which pressure relief must occur. The poor heat exchange efficiency of the water cooler at the outlet of the ammonia compressor has become a key constraint limiting full-load operation of ammonia synthesis plants during the summer. Given that under conditions of high circulating water temperature (with the supply water temperature exceeding 30°C) and when the outlet pressure of the ammonia compressor approaches the overpressure relief threshold, it is difficult to fundamentally resolve the problem of gas venting in a short period of time, the Synthesis Center established a special task force to address this issue. The team came up with innovative measures aimed at minimizing gas venting as much as possible. One such measure involved changing the venting location: instead of venting from the third-stage outlet of the ammonia compressor, venting was redirected to occur at the third-stage air intake point. This reduced the amount of unnecessary work performed by the compressor, thereby decreasing the heat generated at its third-stage outlet and significantly cutting down on ammonia losses due to venting ； Secondly, the task force used the large amount of \"big data\" collected, including information on water coolers, ammonia volume, unit speed, and purification conditions, to conduct analyses. This enabled more precise optimization of the matching between the load and speed of the ammonia compressor and the load on the syngas production system, thus realizing \"artificial intelligence\" for the ammonia compressor. Changes in the venting position and optimized operation of the ammonia compressor were implemented based on a comprehensive analysis of 15-day data before and after these changes. As a result, the effective heat exchange temperature of the water cooler at the ammonia compressor outlet increased from 30°C to 32°C. Compared to conditions involving overpressure, this optimization led to a reduction of 5 tons per hour in ammonia vent emissions, thereby effectively minimizing ammonia loss due to venting. Given the current objective conditions of persistently high feedwater temperature and low water volume in the circulation water system, the outlet pressure of the ammonia compressor at the ammonia synthesis unit in the Synthesis Center still approaches the limit for overpressure venting. The Synthesis Center will continue to strive, constantly pursuing innovative solutions to fundamentally resolve the issue of cooling ammonia gas at the compressor outlet, so as to unremittingly work toward achieving stable, long-term, full-capacity, and optimal operations.