I Nyoman Widiasa

Performance of an integrated membrane pilot plant for wastewater reuse: case study of oil refinery plant in Indonesia

AbstractThis paper demonstrates the performance examination of an integrated membrane system (IMS) pilot plant having capacity of 250–300 L/h for oil refinery wastewater reuse of oil refinery plant in Indonesia. The IMS pilot plant consisted of a multimedia filter (MMF), an ultrafiltration (UF) unit, a reverse osmosis (RO) unit, and a membrane bioreactor (MBR) unit. The UF system was used as a pretreatment prior to RO, the RO unit was used to produce cooling water make-up and the MBR system was used for treating RO concentrate. The test results suggested that backwashing with a more frequent interval is needed to maintain stable flux of UF membrane. With the cleaning every 14 days, the resulting RO permeate was stable and able to fulfil the plant requirements of cooling water make-up. Treatment of RO concentrate using MBR unit resulted in permeate having relatively high chemical oxygen demand (COD). Further treatment by adsorption using granular activated carbon (GAC) proved that GAC was an effective meth...

Study on characteristics of PVDF/nano-clay composite polymer electrolyte using PVP as pore-forming agent

Polyvinylidene fluoride (PVDF) based polymer electrolytes have a high dielectric constant, which can assist in greater ionization of lithium salts. The main advantages of PVDF are its durability in long battery operation and its ability to be a good ion conductor. However, the limitation of this polymer is its crystalline molecular structure. Dispersing nano-particles in the polymer matrix may improve the characteristics of the PVDF polymer. This paper aims to investigate the impact of nano-clay addition on the characteristics of PVDF polymer to be used as a polymer electrolyte membrane. In addition, the effect of poly(vinyl pyrrolidone) (PVP) is also investigated. The membrane was prepared by phase separation method whereas the polymer electrolyte membranes was prepared by immersing into 1 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate/dimethyl carbonate (EC/DMC) electrolytes for 1 h. The membranes were characterized by scanning electron microscope (SEM), porosity and electrolyte uptake and ...