Abstract:
PT HS is the world’s leading toy manufacturing company with more than 6,000 workers. Due to the high number of workers in PT. HS, it will impact to domestic activities (toilet discharge). Based on the annual report for wastewater effluent, ammonia from PT HS’s wastewater effluent exceeded the standard parameter from Jababeka Industrial Estate with most cases reaching 50 mg/L. Whereas, the Jababeka Industrial Estate regulation states that the maximum ammonia allowed in wastewater effluent is 10 mg/L. The objectives of this final project is to know the optimum dose of NaOCl 9% on ammonia removal and to know the concentration of residual chlorine after the treatment process. This final project uses the experimental laboratory method to get the primary data which uses the artificial sample as waste water sample based on SNI guideline. This final project, also use the documentation method to calculate the financial consideration. After conducting the laboratory experiment, the results showed that exposure to sodium hypochlorite reduced ammonia concentration in wastewater samples from 50 mg/L to 8.9 mg/L. The ammonia decreased by adding 110 mg/L of NaOCl 9% solution within 30 minutes of contact time and resulting the residual chlorine 0.72 mg/L. The residual chlorine was still in the standard limit did not exceed mg/L. The results also showed that the dose variations of sodium hypochlorite influence ammonia removal. Also, mostly the total residual chlorine forecast will increases with the increasing sodium chlorine dose. In addition, this final project had calculated cost as a based approach to consider the implementation of the project which will use chlorine gas 99% and the result indicates that this project has potential to be implemented with a reasonable benefit cost ratio was 1,66, payback period 3,1 years and Rp 78.436.739 NPV.
