Atlanta Business Chronicle: A sustainable materials startup plans to develop an up to $200 million manufacturing plant that would make “green cement.’ Marietta-based Sriya Green Materials Inc. has developed technology that it claims will slash the cost of manufacturing cement by about a third. Sriya claims its cement-making process can reduce capital equipment costs by up to 45 percent. The technology also promises to cut carbon dioxide emissions in the manufacturing process by nearly 30 percent, CEO …