Question

environmental wngineering

landfill. The 3. Assume aw Assume a waste-to-soil cover volume ratio of 10:1 for a municipal solid waste landll s0.30othe incoming waste to the landill is 15 Jb t and the compactive matio at Volume of 1,000 tons of incoming waste after compaction (in Volume of the landfill used by the soil cover for 1.000 os of wastep after compaction (in place)eps) 14. A 60-t diameter anacrobie digester with 12-t sidewall depth treats $0,000 gpd of mixed primagy and secondary sludge. The mixed sludge has a 3% total solids concentration and is 70% volatile matter. t' (t po The working volume of this anaerobic digester- Ibd (2 pts) The volatile solids loading rate to this anaerobic digester bdt'(a p) The volatile solids loading rate to this anaerobic digester 15. 300 m/d of waste activated sludge at 0.8% solids is to be thickened to 4% solids by dissolved air flotation. m'd (3 pts) gallonsd (1 p Volumetric flow rate of the sludge after thickening Volumetric flow rate of the sludge after thickening

Answer 1

13.)

Here for a municipal solid waste fill we have,

Average density of incoming waste,γ_{​​​​​​} = 16 lb/ft³

Compaction ratio = 0.3

a.) Volume of 1000 tons of incoming waste after compaction

Volume of 1000 tons of waste ( without compaction)=(1000 ×2000 lb)/γ

V = 2000000/16 ft³ = 125000 ft³

Volume after compaction = 125000 × 0.3 ft³ = 37500 ft³

b.) Volume of landfill used by the soil for 1000 ton of waste

As the waste to soil cover ratio is 10:1,thus for 10 ft³ of compact waste 1 ft³ of soil cover volume will be required,

Thus for 37500 ft³ of compact solid waste = 37500/10 ft³ = 3750 ft³ of soil cover volume will be required.