Petroleum and Coal Pet Coal (2019); 61(6) 1487-1493 ISSN 1337-7027 an open access journal Article Open Access EXPERIMENTAL INVESTIGATION OF MODIFIED STARCH FROM WHITE CORN AS A KINETIC INHIBITOR OF GAS HYDRATE Odutola Toyin Olabisi, Chukwu Uche John, and Monday Celestine Udim 1 Department of Petroleum and Gas Engineering, University of Port Harcourt, Nigeria Received September 13, 2019; Accepted December 9, 2019 Abstract Economic and environmental considerations have motivated the search for kinetic inhibitors from readily available and inexpensive materials to effectively control gas hydrate formation and provide flow assurance in oil and gas production systems. This work experimentally investigate d the effect of modified starch in inhibiting gas hydrates. The starch from white corn was modified by oxidation and applied in low dosages (0.01wt%, - 0.05wt %) in a constant volume experiment conducted in a laboratory hydrate flow loop used to simulate subsea pipelines. The pressure time profile for expe- riments conducted was evaluated based on the gas dissolution time, nucleation time , and hydrate growth time. The effectiveness of the modified starch was indicated by how much gas was used up in forming hydrates during the experiments conducted. 0.04wt% of modified starch was the optimal dosage of inhibitor in this study as it showed less reduction in pressure implying less gas was used. When the performance of modified corn starch was compared with the performance of similar experiments done in the same equipment using polyvinylpyrrolidone (PVP), N-vinylcaprolactam (PVCap), and 2-(dimethylamino)ethylmethacrylate (DMEM) as hydrate inhibitors, Modified starch performed best. Modified corn starch is an efficient, inexpensive and environmentally friendly hydrate inhibitor. Keywords: Modified starch; Kinetic hydrate inhibitor; Flow assurance; Offshore production; Hydrate inhibition. 1. Introduction Natural gas is typically composed of methane, which is often accompanied by higher mo- lecular weight hydrocarbon gases and non-hydrocarbon gases. Hydrate formation is a big flow assurance challenge to surface production. It can block surface production facilities and flow lines, causing a reduction in production, increased back pressure, and, ultimately, a rupture or explosions. Subsequently, this can lead to environmental and equipment damage as well as the loss of life. Flow assurance is of dominant importance in systems where associated problem troubleshooting and subsequent intervention are time consuming [1] . Flow assurance deals with the continuous flow of hydrocarbon from the reservoir through surface production facilities and transport channels to the point of sale in harmony to production plans. Gas hydrates are ice-like crystalline inclusion compounds that are formed at high pressure and low temperature conditions in the presence of water and gas hydrate formers such as methane, ethane, or propane [2] . Hydrate formation is greatly influenced by the nature of the reservoir fluid produced. Hydrates can be formed both in oil and gas systems when one or more hydrate guest molecules (Figure 1) is present in the reservoir fluid. The gas molecules (guests) are trapped in water cavities (host) that are composed of hydrogen-bonded water molecules. These crystalline compounds are divided into three main types of crystallographic structures: structure sI, structure sII, and structure sH (Figure 1). The most abundant hy- drates are of types of structure sI and sII. The third structure, sH, is rarely seen outside the laboratory [3] . 1487