Gas hydrate formation is known as undesirable phenomena in oil and gas process equipment and pipelines. In hydrocarbon reservoirs, Natural gas and crude oil are in contact with water. Hydrate formation in various sectors of oil and gas industry can cause clogging or damage to pipelines, nozzles and other related equipment. This thesis examines the rate of formation and growth of hydrate particles in oil transmission pipelines, where the presence of oil, gas, and emulsion droplets of water dispersed in oil, have provided the conditions for hydrate formation. First, by determining the temperature and pressure distribution in the pipeline, as well as calculating the equilibrium temperature of hydrate formation by the Chen-Gou model, the points in which the equilibrium conditions are available for hydrate formation are identified. Using the homogeneous model for emulsion, the pressure drop in the tube is calculated. According to the flow conditions, the properties of water in oil emulsion have been determined. Because the hydrate nucleation process usually occurs with a delay after providing thermodynamic condition, thus normal distribution is used to determine the nucleation time in each droplet. In this thesis, each droplet of water is considered as a separate reactor, by determining the size of droplets, and using existing equations to determine the growth rate of hydrated crystals, the hydrate volume generated during the process for the system containing methane, water, and decane are calculated. By calculating the amount of hydrate in the system, and using existing equations for the rheology of suspension flows, the apparent viscosity of the hydrate suspension in decane is calculated. When the apparent viscosity faces a sudden increase, the pipeline will be plugged. Finally, the effect of ant-agglomerate inhibitors on the apparent viscosity of suspension has been investigated. By using the Chen-Gou model to calculate the equilibrium temperature of methane hydrate formation, 0.024% error was obtained. Assuming homogeneity of the fluid, 8% error was obtained to determine the pressure drop in water in oil emulsion. Also, if each water droplet considered as an independent reactor for hydrate formation, in the system containing water in decane emulsion and methane gas, the accuracy of methane gas consumption is estimated to be between 13% and 18%. By investigating the use of anti-agglomerate inhibitors, the results showed that the use of these inhibitors decrease the rate of agglomeration of hydrate particles in the suspension due to the correction of the water-hydrate contact angle and the reduction of interfacial tension between water and oil. By decreasing the rate of agglomeration of hydrate particles, the apparent viscosity of the suspension is increased at a lower rate than the condition that we do not use the inhibitor, and consequently the pipeline blockage is delayed. Keywords: Gas hydrate, Water in oil emulsion, Hydrate growth kinetic, Population balance