Enviva Partners LP has released third quarter financial results, reporting increased revenue, net income and gross margin. The company also announced plans to expand its operations, including the addition of new capacity at two existing pellet plants.  During an investor call, John Keppler, chairman and CEO of Enviva, discussed expansion and growth opportunities that he said could more than double the size of the company over the next few years.  Subject to receiving the necessary permits, Keppler said Enviva plans to invest approximately $130 million to increase the aggregate production capacity at its Northampton, North Carolina ...