Investigating the performance of trickling filters with coated plastic bottles in industrial effluent treatment.
Abstract
In food and beverage industries, water is used as an ingredient, a cooling agent, principle agent
for sanitizing plant machinery and work areas. As a result of extensive use of water, large
amounts of wastewater are produced and this wastewater must be treated effectively before
release to the receiving environment. Wastewater treatment process must be cost effective and
the water reused if possible to reduce costs. Century Bottling Company (CBC) is located in
Namanve industrial park and was established in Uganda in 1974 by a Greek family. Wastewater
treatment plant at CBC includes the inlet bar screen, grit collection chamber, balancing tank,
high rate trickling filter, high rate clarifier, submerged aerobic fixed film reactor, sand filters and
carbon filters. The plant operates at flow rates between 40 and 60 m3/h treating 800 m3 to 1200
m
3of wastewater daily. A study to investigate the performance of trickling filters (TF) with
coated plastic bottles in industrial effluent treatment was carried out.
The TF was designed with coated plastic bottles for attachment of the biofilm and its
performance in industrial effluent treatment monitored.The materials and methods describe the
effluent sampling, laboratory analysis, design of TF with coated plastic bottles and monitoring of
the experimental setup.The performance of the existing plant was done by comparing the
different effluent parameters of the WWTP at CBC with the permissible NEMA (1999) Effluent
Standards. The WWTP at CBC was found to be effective and efficient.
The result analysis and discussion section is about characterization of the wastewater at CBC,
evaluation of the performance of the existing treatment plant at CBC and to investigate the use of
coated plastic bottles as an alternative filter media. From the tests carried out on the samples
picked at the outlet of the BT at CBC, the composition of wastewater influent at CBCwas pH of
8.49±0.0198, temperature of 29.03±0.03540C, TDS was 772.43±5.3387 mg/l, DO was
0.81±0.0354 mg/l, colour was 58.61±0.1591 PtCo, turbidity was 46.05±0.1061 NTU, Sulphates
were 71.62±3.7123 mg/l, phosphates were 4.79±0.0778 mg/l, TN was 4.15±0.2121 mg/l, COD
was 1368.50±9.5459 mg/l, BOD was 779.38±19.6222 mg/l and Aluminium was 0.39±0.0177
mg/l.
In conclusion, the comparative analysis showed an increase in the removal efficiency of each
parameter with time and this was graphically represented for both the setup 1 and setup 2. The
removal efficiency by the 23rd day of COD was 92.79%, BOD was 90.09%, TDS was 52.99%,
turbidity was 19.41%. All the effluent parameters conformed to NEMA permissible limits. It was
therefore concluded that the use of coated plastic as an alternative filter media in treatment of
industrial wastewater was generally effective.