Small-scale Incineration of Waste for Energy Recovery

Does anyone ​have experience ​with small-​scale ​incineration of ​waste streams ​including ​sewage sludge ​in small units ​i.e capacity as ​low as 1.5 ​tonnes/day, ​with provision ​for energy ​recovery?  ​

Is it ​profitable? ​What amount of ​energy do you ​gain? ​

Specifically, ​how much energy ​can be ​recovered from ​a tonn of ​sewage sludge?​