There are three main types of volcano-composite or strato, shield and dome. Composite Volcanoes. Composite volcanoes, sometimes known as strato volcanoes, are steep sided cones formed from layers of ash and [lava] flows.The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava.A pyroclastic flow is a superheated mixture of hot steam, ash, rock and dust.omposite volcanoes, sometimes known as strato volcanoes, are steep sided cones formed from layers of ash and [lava] flows. The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava. A pyroclastic flow is a superheated mixture of hot steam, ash, rock and dust.
Desalination plants typically use reverse osmosis, a process that pushes saltwater through a membrane to create purified, drinking water. But in addition to being costly, and energy-intensive, reverse osmosis can negatively impact the environment.
But desalination is expensive. A thousand gallons of freshwater from a desalination plant costs the average US consumer $2.50 to $5, Pankratz says, compared to $2 for conventional freshwater.ut desalination is expensive. A thousand gallons of freshwater from a desalination plant costs the average US consumer $2.50 to $5, Pankratz says, compared to $2 for conventional freshwater.