Ammonia is one of the most important industrial commodity due to its wide function. Ammonia synthesis reaction is an exotermic reaction. Therefore, Feed-Effluent Heat Exchanger (FEHE) is added to increase thermal efficiency. However, FEHE could lead the process to experience hysteresis phenomenon due to interaction between equipments as one steady state T feed could result several T outlet. Hysteresis phenomenon may result asset losses like explosion, leakage, and loosing material integrity. Double bed reactor configuration allows us to use several operating parameters as variation to overcome hysteresis. In this review, quenching ratio was chosen to be that varied parameter. This study aims to determine how quenching ratio affects hysteresis zone by utilizing Aspen Hysys® V8.8 as simulation tool. Simulation showed that quenching ratio would narrow hysteresis zone yet increased extinction temperature that lower the conversion. Conversion profile showed that 0.2 quenching ratio got the highest conversion for system with bed volume ratio 2:1 while total volume was 30 m3. However, the feed temperature was fallen at hysteresis zone. Dynamic simulation showed that highest conversion feed temperature (10%ΔTf above extinct temperature) was still able to preserve stability with descending temperature approach. Hysteresis itself started to occur at 1.7%ΔTf above extinct temperature

Previously, well monitoring in Siak block relied on production crew scheduled tour that needed six hours to complete one cycle of all wells in Lindai field. This paper describes the utilization of digital technology to observe well parameters while sending notification if there is any anomaly regarding those parameters through smart phone application or website. Smart microcontroller was installed in wellhead panel and three sensors are mounted in desired point around wellhead to perform online Intelligent Well Monitoring (IWM) for well’s parameters. If abnormality occurs, real time notification would be sent to user’s smart phone application or website by using global mobile communication system (GSM) signal. The parameters monitored were pressure, temperature, and load because they are essential to be analyzed as initial diagnosis of well problem. Based on the readings, production team could quickly perform troubleshooting to prevent loss production opportunity (LPO). The programming of this smart microcontroller used C language as data compiler. This method was tested in one of the wells in Lindai field, which has the highest oil production. After three months of surveillance, in terms of data quality, the values shown by this tool had only five percent differences compared to manual survey using calibrated measurement tools. Additionally, the parameters could be monitored online, real time, and gave the notification directly to users should there be any issues. Moreover, this tool could reduce the response time of the field crew significantly from six hours following the conventional field tour to only in five minutes by relying on real time notification. In addition, the operational cost of this tool was 82% cheaper compared to other well-known online monitoring tool available in the market so it is considered economical. In the long term, this tool will be implemented on all wells in Siak block for integrated real time monitoring. Furthermore, the impact of field scale implementation will be much greater such as increasing data accuracy by eliminating human error from manual well checking and improving safety of the crew by reducing the possibility of fatigue. The utilization of smart microcontroller for online well monitoring is beneficial for marginal field with high number of wells and wide field coverage. Earlier, real time well monitoring is usually considered expensive investment that rarely become priority. However, the implementation of IoT (Internet of Things) by using this tool can be the game changer in marginal field and maximize the well’s production by reducing LPO.

Penelitian ini bertujuan untuk mengetahui perilaku korosi aluminium dalam larutan asam sitrat pada kondisi fluida dinamis. Pengujian laju korosi dilakukan dengan menggunakan Rotating Disk Electrode (RDE) dan potensiostat. Konsentrasi asam sitrat divariasikan 2%, 3,5% dan 5%-w/v pada rejim aliran transisi dan turbulen. Hasil penelitian menunjukkan laju korosi aluminium yang ganas, dalam rentang 2,12-24,86 mm/tahun. Konsentrasi asam sitrat 5%-w/v memberikan laju korosi aluminium yang lebih rendah akibat pembentukan lapisan pasif. Reaksi korosi yang terjadi bersifat irreversible satu tahap dengan produk korosi berupa Al 2 O 3 yang tidak stabil.