dc.description.abstract | Manufacturing of paper by recycling of waste paper is
currently receiving attention allover the world especially in
the developing countries as a consequence of the high cost
associated with production of paper from wood and the global
environmental campaign against deforestation. As paper
manufacturing from waste paper involves many steps of process,
it results in effluents whose characteristics vary
considerably.
Application of Anaerobic treatment systems in the developing
countries especially tropical countries (e.g. sub-saharan) can
highly be feasible because the system could be operated
successfully at ambient temperature and hence the cost for
heating the system will be omitted. Moreover, the methane gas
produced by such systems can contribute considerably to
solving the problems associated with energy availability in
these countries.
In this study, the characteristics of a recycled paper mill
(Chandaria paper mill, Nairobi, Kenya) waste water was
investigated and the feasibility of its treatment
anaerobically was studied in a laboratory scale UASB rector.
The waste water was found to be highly biodegradable with a
COD concentration ranging between 1900 and 2300 mg/1 and a BOD
cencentration ranging between 1100 and 1300 mg/1. The COD/BOD
cerrelation being expressed by:-
BOD5 = 0.59 COD + 2.24
The tetal suspended selids cencentration was in the range of
500-900 mg/l. The waste water was acidic (PH between 3 and 5)
and deficient in basic inerganic nutrients (phosphereus 3-5
mg/l and NH3-N 0.0). Appreximately all the tetal kjeldahl
nitrogen (TKN) exist in the waste water was asseciated with
erganic matter at a concentratien ef 11-26 mg/l. The sulphate
centent was between 87 and 164 mg/l. The final industrial
effluent flow rate was ranging between 1700 and 2100 m3/d and
the waste water temperature level was at 22-28°C.
The treatability study shewed that, it is feasible to. treat
this waste water in a UASB system seeded with sludge frem a
municipal anaerebic digester at ambient temperature (average
22°C) whereby the efficiency ef the erganic content remeval in
terms ef seluble COD was 58-~3% at an optimum erganic leading
rate between l2-l5Kg COD/m3/d. This corresponded to. a
hydraulic retentien time (HRT) of 3 hours at an influent COD
cencentratien ef 2100 mg/l. The average total biegas
preduction was equivalent tro 0.2 litre/g COD remeved.
Measurement ef different was~e water parameters; COD, shert
chain fatty acids (prepienic and acetic acids), sulphate, pH,
free and saline ammonia, organic nitrogen, and total suspended
solids; along the rector length provided interesting
information regarding the system behavior. The results
conform with results obtained elsewhere. | en_US |