Feed and effluent heat exchangers in 3.2 MMTA CCR unit, 3.2 MMTA disproportionation unit and 3.6 MMTA isomerization unit were replaced in October 2017 with spiral tube heat exchangers (STHEs) designed and manufactured by ZPJE. After installation, the hot approach temperature (HAT) of feed and effluent heat exchanger in reforming unit has been reduced from 37℃to 16℃ (at 80% design capacity). The HAT of feed and effluent heat exchanger in disproportionation unit has been reduced from 31℃ to 21℃. The pressure drop of feed and effluent heat exchanger in isomerization unit has been reduced from ~160kPa to ~70kPa）. The product yield has been improved with a significant energy saving, which can bring our company annual benefit of around 0.2 billion RMB (30 million $).

The feed and effluent heat exchangers applied in these three units were originally welded plate heat exchangers, and were replaced with ZPJE’s STHE due to fouling and leakage. 

(said the vice general manager of Equipment, Ningbo Zhongjin petrochemical )