80    A COMPARISON OF TREATMENTS FOR HIGH STRENGTH
DISTILLERY SLOPS
FROM THE SUGAR CANE INDUSTRY
Hector M. Poggi-Varaldo, Associate Professor
Center of Advanced Studies and Research,
CINVESTAV del IPN, Dept. of Biotechnology and Bioengineering
Mexico D.F., Mexico
INTRODUCTION
The industrial activity is the main contributor to the water pollution in Mexico. The sugar cane
processing industry is the major wastewater generation source with nearly 60% of the total discharges1 (Figure 1). The distillery slops from alcohol manufacture based on molasses fermentation
account for an important amount of the organic load of these emissions.
The distillery slops, known as vinasses, can be very aggressive to the environment when improperly
managed. They have low pH and high contents of suspended and dissolved organic matter and
nutrients. On the average, each liter of alcohol distilled generates 12 to 14 liters of vinasses. The
potential environmental impact of a distillery manufacturing 500 m3 alcohol/day is equivalent to that
of a city of 200,000 inhabitants.2 In 1989, about 1,500,000 m3 of vinasses were discharged in Mexico
in parallel to a production of 115,000 m3 of alcohol.3,4
Recycling and resource recovery from vinasses is a very dynamic area of research.5 Current experiments in the CINVESTAV in reusing/recycling vinasses for alcohol fermentation or single cell protein
synthesis show promise (V. Lopez-Mercado and M. de-la-Torre, private communication, CINVESTAV, 1992). Although reuse and recycle could alleviate the vinasses' pollution problem in the future,
SUGARCANE  62,0%
CHEMICAL   2.1*
PULP AND PAP   10.0%
/inaasi
ANAEROBIC FLUIDIZED
BED REACTOR
OIL  3.1%
OTHERS  19.0%
Anaerobic Efftuant
I	
AEROBIC FLUIDIZED
BED REACTOR
STEEL 3.8%
Aaroblc Effluant
TOTAL: ONE BILLION M3/YR
LYSIIIV
IT
Tipwittr
TERS
V
r
T
Figure 1.    Industrial wastewater discharges in      Figure 2.    Experimental design flowsheet.
Mexico-contributions of industrial sectors.
47th Purdue Industrial Waste Conference Proceedings, 1992 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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