Volume 23 - 2021

A pilot-scale sequencing batch reactor (SBR) for anaerobic ammonium oxidation (anammox) of bacteria culture was used along with a batch experimental reaction device to study the effect of NO2--N concentration on the activity of anammox bacteria and the recovery of N2H4 on anammox bacteria after inhibition by high concentrations of NO2--N. The optimal influent NO2--N concentration in the pilot-scale reactor was 72.0 mg/L, with its total nitrogen consumption being approximately 40.0 g/d. Influent water NO2--N concentrations greater than 100 mg/L had a serious inhibitory effect on the anammox bacteria. At an influent NO2--N concentration of 120.35 mg/L, the addition of 10.0-15.0 mg/L of N2H4, restored the activity of granular anammox bacteria; the total nitrogen consumption was increased by 69.96%. Microbiological analysis showed that a change in NO2--N concentration within the range of 18.87-115.39 mg/L did not affect the microbial population structure of the pilot-scale reactor, wherein Candidatus Kuenenia was the dominant bacterial species. In samples collected at stages A0 (sludge inoculation), A20 (the number indicates the NO2--N concentration, which, in this stage, was 20 mg/L), A40, A60, A80, and A100, the proportion of Candidatus Kuenenia was 27%, 23%, 36%, 26%, 34%, and 33%, respectively.

This study was conducted to analysis of the Environmental Sensitivity Index (ESI) for anticipating the effect of oil spills on the environment in coastal areas. The study location is the coastal area and waters of the Karas District, Fakfak Regency, West Papua Province, Indonesia. The purpose of the study is to determine the priority of areas that are sensitive to oil spills. This method was carried out by scoring each unit of land based on vulnerability, conservation, and social values. ESI Analysis was carried out through geographic information systems and classified into 5 classes of sensitivity levels. The land use classification was carried out through satellite imagery and field surveys conducted in December 2018. The results of resource classification can be divided into 16 classes. The ESI analysis showed that most (51%) were categorized as insensitive, sensitive low 24%, very sensitive 15%, moderately sensitive 6%, and sensitive 4%. Although most are not sensitive, it should be followed by effective environmental protection to maintain sustainable development.

Sodium dodecyl sulfate sulfate modified Algerian cork powder (SDS-ACP) with interesting biosorption capacity was prepared for dye removal from aqueous media. The decolorization performance of SDS-ACP was studied using methylene blue (MB) as a model dye. Experiments were conducted in batch sysytem. The effects of initial pH, biosorbent dose, dye concentration, contact time and temperature were investigated. The kinetic modelling study showed that the experimental data are perfectly adjustable to the pseudo-second order model, with regression coefficients close to the unity and the intraparticle diffusion is not only the key controlling-step in the biosprption process. Langmuir isotherm was the most suitable model for describing the biosorption equilibrium results, which confirm the monolayer coverage and the maximum biosorption uptake of SDS-ACP was 117mg/g. Thermodynamic parameters such as Gibbs free energy, entropy and enthalpy were also evaluated showing that the biosorption process was spontaneously feasible and exothermic in nature. The application treatment has shown that SDS-ACP is a suitable lignocellulosic-type biosorbent for the decolorization of MB-colored solutions

Production of glycerol carbonate (GLC) that is a fuel additive from green solvent dimethyl carbonate (DMC) and biodiesel by-product glycerin is environmentally friendly synthesis. The usage of waste glycerol from biodiesel plant makes the production cost lower. When the membrane aided technique is used for the production of GLC, this technique will be very promising technique. Because membrane applications are environment and energy friendly economical applications. The production with membrane aided can be made by catalytic membrane. In this study, catalytic membranes were developed from synthetic and natural materials to produce GLC by transesterification reaction between glycerol and DMC. The reaction gives methanol as byproduct. The catalytic membranes were used methanol retentive material for increasing the reaction conversion of glycerol to glycerol carbonate. The synthetic catalytic membrane materials were poly(vinylalcohol)(PVA), poly(vinylpyrrolidone) (PVP), Poly(4-vinylpyridine) (P4VP) polymers and CaO. The natural catalytic membrane material was chitosan biopolymer and waste eggshell. The properties of by-product methanol retentive of the polymeric membranes were determined from sorption tests. The tests were shown that the catalytic membranes would sorp by-product methanol during reaction. This pointed out that GLC synthesis can be made by membrane aided technique such as membrane reactor.