Research on the effectiveness of LDAR and precise emission reduction strategies of five typical petrochemical companies

Leak Detection and Repair (LDAR) is an essential control measure for the fugitive emission management of VOCs in petrochemical companies and has been implemented in China for over a decade. However, there is a notable absence of authoritative research concerning the leak ratio of fugitive emissions from affected components of affected equipment and pipeline components within petrochemical companies. This study selected five typical petrochemical companies as subjects of research, with the processing scale and processing routes serving as the two main threads. Based on more than 6 × 10⁶ pieces of measured data, a systematic analysis was conducted to assess the fugitive leak ratios at affected components, using the correlation equation method. The results indicated that the number of static components such as connectors, flanges, and valves accounted for 97.9% of the total number of affected components. Simultaneous, the average leak ratio for all affected component was approximately 0.2%, which was below the average leak ratio (1.5%) of Chinese refineries. When examining the leak ratios from different processing routes, it was observed that fuel-type petrochemical companies have the highest leak ratio (0.2%) due to their earlier establishment, which is influenced by the limitations of the equipment installation technique in the early years as well as wear and tear of the affected equipment and pipeline components. The refining-chemical integration type companies tend to be larger than the fuel-lubricant type companies and have a higher number of affected components, resulting in a higher leak ratio (0.1 %) than the fuel-lubricant type refinery (0.03%). Simultaneous, the average leak ratio for open-ended lines was relatively high, about 0.9%, followed closely by valves and pump, making them the focal point for VOCs emission reduction in petrochemical companies. The findings of this study will ensure the effectiveness of leak control in LDAR work and provide a reference for the government to formulate refined control measures for VOCs leakage.