Convert Pounds per day to Grains per second

Convert Pounds per day (lb/d) to Grains per second (gr/s) instantly and accurately.

Pounds per day (lb/d)
Grains per second (gr/s)

Conversion Formula

gr/s = lb/d × 0.08101851852

About Pounds per day

The pound per day (lb/d) equals 0.45359237/86400 ≈ 5.249×10⁻⁶ kg/s, used in wastewater engineering for reporting biochemical oxygen demand (BOD) loads, nutrient loadings, and sludge production. US NPDES permits set effluent mass-load limits in lb/d; a municipal WWTP serving 10 000 people generates roughly 1 500-3 000 lb/d of dry sludge solids. 1 lb/d ≈ 5.249×10⁻⁶ kg/s.

About Grains per second

The grain per second (gr/s) equals 64.79891 mg/s or 6.479891×10⁻⁵ kg/s. The grain (= 1/7000 lb exactly) is the smallest avoirdupois mass unit, still used in ballistics for bullet and propellant-charge weights. A .308 Winchester rifle bullet of 168 gr fired in 1 s represents 168 gr/s; powder charge is typically 40-46 gr. 1 gr/s = 6.479891×10⁻⁵ kg/s = 64.79891 mg/s.

Quick Reference Table

Pounds per day (lb/d)Grains per second (gr/s)
1 lb/d0.0810185 gr/s
2 lb/d0.162037 gr/s
5 lb/d0.405093 gr/s
10 lb/d0.810185 gr/s
25 lb/d2.02546 gr/s
50 lb/d4.05093 gr/s
100 lb/d8.10185 gr/s

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