Abstract:
PT. Jababeka Infrastruktur is a subsidiary company of PT. Jababeka
Tbk., which have a role as estate manager. One of PT. Jababeka
Infrastruktur duty is to manage Wastewater Treatment Plant 2
(WWTP2). The incoming wastewater pH in WWTP2 PT. Jababeka
Infrastruktur tend to be low and fluctuating, it is because the most
incoming wastewater quantity came from food industries, where it has
a potential to degrade into fatty acid. pH is one of the important
parameters in treating wastewater, especially in biological wastewater
treatment system as applied in WWTP2. pH value can affect the
microorganism performance in decompose the pollutant compound in
wastewater. pH control action is needed to make the treatment run more
effective. The purpose of this research was to know the primary settling
tank (PST) with ̴ 3 hours detention time performance in equalizing
wastewater pH. The research also aims to analyse whether existing PST
detention time met the preferred value, and to find out whether utilizing
existing PST as equalization tank than building new equalization tank
based on hydraulic system and financial aspect. The method used in this
research was statistical analysis of secondary data by comparing
standard deviation value of wastewater before and after accommodated
in PST also paired sample t-Test to see the performance of PST in
equalizing of pH. Besides that, inlet wastewater pH was taken and
measured every one hour with and without adding to the previous
wastewater inlet sample to determine the preferred wastewater
detention time in terms of pH. The research result showed that PST was
significant unit process that can equalize the pH value. The observation
of pH characteristic pattern by time showed that the preferred
equalization time was 1-2 hours which less than the existing PST
detention time. The financial analysis showed that, developing new
equalization tank is a better alternative rather for full (24 hours)
operation. However, if the pH of inlet wastewater can be controlled so
that the pH value is less than 6.5 as much as 17%, utilizing the existing
PST as an emergency unit is a better alternative.
