Since many years WEHRLE and E-Square cooperate on successful projects concerning waste water treatment in Thailand.
Together with E-Square, WEHRLE now designs a treatment plant for MBT wastewater, based on WEHRLE’s high performance membrane bioreactor (BIOMEMBRAT®) including reverse osmosis and nano filtration process steps for the Bangkok Metropolitan Administration (BMA).
For this plant, WEHRLE could combine several of its particular strengths: high cleaning performance, uncompromising plant reliability and low operating costs.
The treatment target is a direct and reliable discharge of the treated water into nature.
Besides the high level of ammonium, the plant is confronted with a very high level of Total Dissolved Solids which leads to high demands on the process and material combination.
With a relatively low amount of COD (Chemical Oxygen Demand) that needs to be maintained, the strict regulations regarding the discharge of Total Dissolved Solids must be fulfilled. Moreover, a high permeate yield is to be generated while nitrogen is to be eliminated at the same time. The best solution to tackle this challenge is the WERHRLE‘s BIOMEMBRAT® high performance membrane bioreactor plant with additional reverse osmosis and nano filtration treatment steps.
A partial stream from the MBR is processed by the reverse osmosis and the other part is processed with the nano filtration. With using only a reverse osmosis the COD and TDS limits would not be exceeded, however BMA would be confronted with a high amount of concentrates leading to high costs for disposal and operation. If only a nano filtration plant would be used, the amount of concentrate would be less however the limits of TDS could not be maintained.
Therefore WEHRLE decided to use a combination of both technologies in order to receive the best results. At the end of the treatment chain both permeates are merged. The combination of the technologies has the advantage for WEHRLE’s customer to achieve a low level of Ammonium in the outlet (20 mg/l), a COD of 120 mg/l (inlet volume 8.250 mg/l), low discharge of Total Dissolved Solids as well as reduced operational costs due to reduced amount of concentrate.
After the treatment with WEHRLE‘s BIOMEMBRAT® the water can be discharged to nature or be re-used for example for cleaning or irrigation.