A techno-economic review of gas flaring in Iran and its human and environmental impacts

Today, managing energy consumption in industries has become a necessity. Flaring the combustible gases is the main source of wasting energy in the oil and gas explorations, refineries, and petrochemical industry. Flaring contributes to the release of large amounts of environmental pollutants, such as CO2, SOx, NOx, and hydrocar-bons, as well as other adverse human and environmental effects. In this regard, flaring reduction or recovery of flared gases has become one of the main concerns of the relevant industries. With 17.40 billion cubic meters (BCM) of annual flared gasses, Iran held the third rank among the top most gas flaring countries in 2021. Flaring such an amount of gas signifies a considerable economic loss as well as the emission of large volumes of greenhouse gasses (GHGs). Air pollution caused by flaring is a long-lasting problem in the oil-rich regions of Iran, while traces of heavy metals have been found in the Zagros ecosystems in the soil and tree leaves. We have also presented the most updated status of flare gas recovery (FGR) projects (AMAK, Kharg NGL, and Siri projects) with some promising results. To analyze the recovery potential of flare gases in Iran, different technologies and decision-making factors have been critically reviewed with the goal of finding the best recovery methods. Based on our study, there are new hopes for investment, particularly from the private sector, despite some resistance in the oil and gas administration. The proximity of Iran's giant petrochemical complexes to the major associated and non-associated gas flaring sites and the feasibility of their utilization as the feedstock signal favorable changes and is a positive outcome of this research. The expected rate of return (ROR) for feedstock production is between 120% and 250% and payback period (PB) between 0.4 and 1.2 years. Due to massive inflation and difficulties in foreign financing and technology transfer, we recommend more straightforward recovery methods despite lower profit. In this regard, apart from feedstock utilization of associated gas, we recommend electricity generation from flare gases for smaller amounts of flaring since the technology is more available and the country is always in shortage of the product (electricity). The ROR and PB for electricity generation are reported to be between 15% and 40% and 2.5-6.5 years, respectively.