The Project – Waste Water Treatment Solutions in Pulp and Paper Industry
Thai Cardboard Co Ltd situated near Bangkok is a reputable manufacturer of cardboard for printing and molded pulp products.
THE EFFLUENT EXISTING TREATMENT PLANT
Production activities within the plant premises generates approximately 1.5 to 2 MLD of effluent which is treated in a wastewater treatment plant comprising DAF followed by Micro Screens. The Primary treated effluent is then further treated biologically in a conventional activated sludge process.
EXISTING THE EFFLUENT
- DAF
- Micro Screens
- Activated Sludge
- Secondary Clarifier
Fig 1 : Existing Treatment Unit
THE PROBLEM
The existing activated sludge process was facing a severe bulking problem having SVI values of 800-900 ml/g in addition the outlet COD was very high, 320 mg/lit which required to be controlled in order to meet discharge limits. The excessive bulking has caused severe sludge floating and thus restricted the plants operation reducing the treatment capacity.
THE SOLUTION – Waste Water Treatment Solutions in Pulp and Paper Industry
In order to solve the clients specific issues related to sludge bulking, COD reduction and additional treatment capacity, trials were conducted at site with Levapor carriers.
After a successful trial run of the pilot plant, it was confirmed that the addition of Levapor carriers certainly improved the; COD reduction, sludge settling properties reducing bulking and also allowed for higher flow rates increasing the plant’s treatment capacity.
THE RESULT
After adding Levapor carriers in the existing activated sludge with little modification, within a few weeks the plant had achieved remarkable improvement in the settling properties of sludge reducing bulking as well as COD reduction. COD reduction had improved drastically achieving a COD reading of < 100 ppm at the clarifier outlet. Due to better performance of the clarifier the unit was also able to treat higher flow rates through the biological process increasing the plant’s overall treatment capability.
Fig 2 : Results of the Pilot testing conducted at site. Fig 3:
BENEFITS OF LEVAPOR IFAS SOLUTIONS AT THAI CARD BOARD:
- Higher flow rates to the tune of 2 MLD from same plant
- COD < 100 ppm at the outlet of secondary clarifier
- Reduction in sludge bulking and lower TSS carryover in the treated effluent