4: The sludge from a wastewater treatment plant serving 500,000 persons, is currently disposed of in a sanitary landfill
Posted: Fri Mar 04, 2022 9:50 am
4: The sludge from a wastewater treatment plant serving 500,000
persons, is currently disposed of in a sanitary landfill. Because
the capacity of the existing landfill will soon be exhausted, it
has been proposed to combust the sludge using processed MSW as a
fuel source. Two alternative modes of operation are to be
evaluated. In the first mode, sludge with a fuel value of 17,445
kj/kg of dry matter. And a solids content of 5% are to be mixed
with processed MSW (11,781 kj/kg) and combusted. In the second
alternative, dewatered sludge with a solids content of 20% and a
fuel value of 15,119 kj/kg (based on dry solids is to be mixed with
the processed MSW before being combusted. It should be noted that
the fuel value of the dewatered solids is lower because of the
chemicals added to aid in dewatering. Assuming that the specific
gravity of the combined dry sludge with or without the addition of
chemicals is 1.10, the per capita sludge production on a dry basis
is 0.16 kg/day, and the moisture content of the processed MSW is
20%. Determine the amount of MSW that must be added to the
treatment plant sludge for both alternatives to achieve a final
moisture content of 60%. Would the required quantities of processed
MSW be available in the wastes from the community? Clearly state
all your assumptions.
persons, is currently disposed of in a sanitary landfill. Because
the capacity of the existing landfill will soon be exhausted, it
has been proposed to combust the sludge using processed MSW as a
fuel source. Two alternative modes of operation are to be
evaluated. In the first mode, sludge with a fuel value of 17,445
kj/kg of dry matter. And a solids content of 5% are to be mixed
with processed MSW (11,781 kj/kg) and combusted. In the second
alternative, dewatered sludge with a solids content of 20% and a
fuel value of 15,119 kj/kg (based on dry solids is to be mixed with
the processed MSW before being combusted. It should be noted that
the fuel value of the dewatered solids is lower because of the
chemicals added to aid in dewatering. Assuming that the specific
gravity of the combined dry sludge with or without the addition of
chemicals is 1.10, the per capita sludge production on a dry basis
is 0.16 kg/day, and the moisture content of the processed MSW is
20%. Determine the amount of MSW that must be added to the
treatment plant sludge for both alternatives to achieve a final
moisture content of 60%. Would the required quantities of processed
MSW be available in the wastes from the community? Clearly state
all your assumptions.