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Treatment of Industrial Effluents, Municipal Wastes, and Potable Water 223
Table 5.4
Coffee factory effluent characteristics
Effluent MBR influent MBR effluent Untreated Post-blended Permitted
Flow gpd 48,900 – 114,915 163,815 237,600
gpm 33.96 – 80 114 165
TSS mg/L 390 0 230 160 500
lb/d 160 0 220 220 990
S-COD mg/L 5,390 250 820 645
lb/d 2,200 100 785 885
T-COD mg/L 6,240 250 1,230 930 2,000
lb/d 2,545 100 1,180 1,280 3,000
BOD5 mg/L 2,780 50 460 335 400
lb/d 1,135 20 440 460 600
TSS = 0 mg/L
S-COD = 250 mg/L
T-COD = 250 mg/L
BOD5 = 50 mg/L
After blending the MBR treated effluent and the untreated low-strength WW together, the
resulting blended final effluent, indeed, met all effluent limitations in the permit.
5.4. Example 4: Cosmetics Industry
The WW discharged from a major cosmetics manufacturing plant in northern France was
originally treated at the local municipal WWTP. Average flow rate was 160 m 3 /d (42,240
gpd). In order to cut down sewer surcharge and fresh water costs, the plant set a goal to
remove 90% of the total COD and recycle at least 30% of the treated effluent for non-process
uses within the plant.
5.4.1. Solution
A pilot aerobic MBR test program was conducted at the plant using a 1 m 3 (264 US gal)
pilot plant to determine treatability and to obtain full-scale design parameters. Results from
the 5-month test program demonstrate the excellent overall performance of the MBR process
system in terms of efficiency and reliability. Removal efficiencies obtained were 98%þ for
COD, 99% for NH3–N, and 99% for FOG (fats, oils, and greases). Removal of TSS was total;
yielding an effluent that could satisfy the recycle criteria within the plant (15, 20).
Following the pilot test program, a full-scale system was designed and installed to handle
150 m 3 /d flow and 1,200 kg/d COD. The membrane filtration unit consisted of ceramic
microfiltration modules, which were modular and suitable for expansion. The plant has been
successfully in operation since the summer of 1994. Despite the variable flow rate and
characteristics of the influent WW (COD 2–6 g/L; COD/BOD5 1.8–2.5), the treated effluent
from the innovative MBR process system has been of consistent high quality (COD < 100
mg/L; BOD < 20 mg/L; TSS 0 mg/L; no bacteria). Part of the treated effluent is recycled for