A dosage of 3 ppm on the crude side and 5 ppm on the reduced crude oil (RCO) and short residue sides was maintained during the trial period. The field trials were initially conducted over eight months, with the results shown in Figure 3 (in green). The average preheat temperature
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Figure 3 Field trials at HPCL Mumbai Refinery
costs. HP ThermoPro has also been found to be very effective across various Russian crudes processed recently in HPCL refineries. Conclusions HP ThermoPro has been developed for mitigating fouling issues in preheat exchangers in refineries. The analysis of fouling scales collected from the tube and shell sides of preheat exchangers provided insights into the different fouling mechanisms, leading to the development of a highly efficient antifoulant formulation. The efficacy of the in-house-developed antifoulant formulations was assessed against various crude oils, crude blends, DHDS feed, and short residue using RPFS, demonstrating superior performance in comparison to control experiments and benchmarks. Subsequently, HP ThermoPro was scaled up to a tonnage scale, and successful field trials were conducted at the HPCL refineries in Visakh and Mumbai, showing enhanced performance relative to benchmark antifoulants. The product is in continuous usage at HPCL refineries. HP THERMOPRO is a trademark of Hindustan Petroleum Green R&D Centre. VIEW REFERENCES Dr. Eswararao Doni doni@hpcl.in Raghava Krishna Kanala krkrishna@hpcl.in Sairamu Madala sairamumadala@hpcl.in
rose by 2.4°C per month with the use of HP ThermoPro. This clearly illustrates the cleaning efficacy of the product throughout the trial period. It also indicates that it is effective across a wide range of crudes, crude blends, and short residues. In the absence of any antifoulant, the preheat temperature dropped by 2°C per month over the same timeframe, as illustrated in Figure 3 (shown in blue). Later, HP ThermoPro use continued for up to 18 months, during which the preheat remained around 260ºC. Subsequently, the product was slightly modified, and a new version, HP ThermoPro-W, was developed exclusively for waxy crudes. Trials were conducted over a period of six months, with the results depicted in Figure 3 (highlighted in orange). Throughout this trial, the preheat temperature remained stable at around 260ºC. Alongside improvements in preheating, a significant decrease was also observed in the number of preheat exchangers cleaned off-line during this timeframe, further adding value to the product (see Table 5 ). During trials and subsequent continuous usage (supplied more than 2,000 MT to Indian refineries), preheat temperatures were significantly improved and reduced the load on furnaces. This led to multifold savings on fuel oil burning and reduced greenhouse gas (GHG) emissions by 11.5% (equal to 12,000 t/CO 2 ) per annum for each crude distillation unit (CDU) unit (with a 3.4 MMTPA capacity). Overall, this contributed to a reduction of 0.3% in GHG emissions from the refineries. It also significantly reduced offline cleaning of preheat exchangers, improving operational efficiency, safety, and reducing maintenance
Refining India
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