Anaerobic-Aerobic Treatment of Sulfite Pulp and Paper mill effluent using high Performance Levapor Carriers for the immobilization of micro-organism. A significant AOX reduction was observed and discharge limits for AOX emission were met successfully providing 80-85% COD reduction with useful bio gas generation for fuel.

1. LEVAPOR
SAPPI- a case history
LEVAPOR GmbH, Leverkusen
www.levapor.com

2. SAPPI – Ehingen (Germany) - Biotreatment of toxic
pulp mill effluents by LEVAPOR-fixed biomass.

3. SAPPI- a case history
APPI , Ehingen (Germany) : 90.000 t/yr pulp (1985)
ite pulp and paper mill,
ching with chlorine.
00 m³/d pulp mill waste water,
ons/day COD,
c effluents.
tests for aerobic biotreatment had achieved only
COD removal (toxicity of bleaching effluents !).
: anaerobic-aerobic treatment ? tests with LEVAPOR-
fixed biomass.

5. Effect of carrier types on COD-elimination under anaerobic
LEVAPOR
activated carbon
unmodified PUR
carrier
suspended
anaerobic culture

7. Vana =65.000 m³ Vana =20.000 m³ Vana =15.000 m

8. SAPPI- case history
Solution: anaerobic pre-treatment using 1500 m³
LEVAPOR  66-70% COD-removal.
Aerobic post-treatment removed further
50% of residual COD.
Anaerobic reactors: only 15.000 m³ instead of 65.000 m
with suspended biomass !
Benefits for customer: 50.000 m³ less reactor volume
Savings for customer: ~ ca. 12 to 15. mio € investition

9. BUFFER +
BIOCOND.
LP MILL
0.000 m³/d
~ 45 t/d
ralised
ANAEROB-
REACTOR
LEVAPO
R
AEROBIC
POST
TREATMENT
CLARIF.
for
AEROB-
REACTOR
Excess slud
4-5 t/d !
BIOGAS
MIXED
EFFLUENT
Q ~ 13.500 m³/d
SAPPI – basic process flow diagram

13. rder to confirm again the contribution of LEVAP
film Technology, for plant startup only two
erobic
ctors had been filled each with 12 % carrier.
er four months after toxic shocks the minor stab
ctor with suspended biomass became inhibited a
more able to recover prior bioactivity, proving th
ortance of immobilisation (next graph).

14. susp.bio
y 90 June 90