It is noteworthy to highlight that ammonia nitrogen contamination in wastewater has been reported to pose a great threat to the environment. This conventional method of remediating ammonia nitrogen contamination in wastewater applies the packed bed tower technology. Nevertheless, this technology appears to pose several application issues. Over the years, researchers have tested various types of ammonia stripping process to overcome the shortcomings of the conventional ammonia stripping technology. Along this line, the present study highlights the recent development of ammonia stripping process for industrial wastewater treatment. In addition, this study reviews ammonia stripping application for varied types of industrial wastewater and several significant operating parameters. Furthermore, this paper discusses some issues related to the conventional ammonia stripper for industrial treatment application. Finally, this study explicates the future prospects of the ammonia stripping method. This review, hence, contributes by enhancing the ammonia stripping treatment efficiency and its application for industrial wastewater treatment.

a b s t r a c tThis review provides insight into various techniques utilized for the treatments of palm oil mill effluents (POME). Generally, POME treatment is achieved in two ways, these are (1) pretreatment stages, involving majorly the reduction of oil and grease and suspended matter and (2) an advanced treatment stage, in which wastewater contaminants (e.g. BOD 5 , COD) are reduced to standard discharge limits. Different methods utilized in the treatment of POME such as coagulation-flocculation, anaerobic, aerobic and membrane technology are explained fully and recent trends in their advancement and improvement are outlined. Though, various pilot or industrial scale treatment plants have been reported in scientific literature for POME treatments methods such as anaerobic, aerobic and membrane technology, the literature is still scarce for application of photocatalytic degradation technology to POME treatment as the technology is still in development stage and has not been fully utilized on an industrial scale in palm oil mill industries. This is mainly as a result of inadequate investigation involving POME degradation. The review presented here is focused on photocatalytic degradation technology and reflects published outcomes with the aim of offering the technique as an attractive and sustainable process units. Also the potential of the process to replace some of the well-known separation and degradation technologies has been highlighted at advanced treatment stage for POME.

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Dengue mosquitoes are evolving into a broader global public health menace, with relentless outbreaks and the rise in number of Zika virus disease cases as reminders of the continued hazard associated with Aedes vectors. The use of chemical insecticidesthe principal strategy against mosquito vectorshas been greatly impeded due to the development of insecticide resistance and the shrinking spectrum of effective agents. Therefore, there is a pressing need for new chemistries for vector control. Tea contains hundreds of chemicals, and its waste, which has become a growing global environmental problem, is almost as rich in toxicants as green leaves. This paper presents the toxic and sublethal effects of different crude extracts of tea on Aedes albopictus. The survival rates of larvae exposed to tea extracts, especially fresh tea extract (FTE), were markedly lower than those in the control treatment group. In addition to this immediate toxicity against different developmental stages, the extracts tested caused a broad range of sublethal effects. The developmental time was clearly longer in containers with tea, especially in those with young larvae (YL) and FTE. Among the survivors, pupation success was reduced in containers with tea, which also produced low adult emergence rates with increasing tea concentration. The production of eggs tended to be reduced in females derived from the tea treatment groups. These indirect effects of tea extracts on Ae. albopictus exhibited different patterns according to the exposed larval stage. Taken together, these findings indicate that tea and its waste affect most key components of Ae. albopictus vectorial capacity and may be useful for dengue control. Reusing tea waste in vector control could also be a practical solution to the problems associated with its pollution.

In this research work, waste cooking oil biodiesel production was optimized using a design of experiment (DOE) approach: response surface methodology (RSM), based on a five level, three variables central composite design (CCD) to investigate the interaction effects of the different combination of transesterification reaction variables such as catalyst concentration, reaction temperature and time, using ostrich eggshell CaO base catalyst. A quadratic polynomial equation of the response, biodiesel yield was attained via multiple regression analysis to predict the relation between yield and the chosen variables. The results showed that the temperature and time are the most important process parameters on the biodiesel production. The optimal operating conditions for the transesterification reaction have been found to be: reaction temperature of 67 °C, alcohol/oil molar ratio of 10:1 (fixed parameter), catalyst concentration of 1.97 % w/w and reaction time of 1.77 h. The predicted biodiesel yield was about 99.67% under the optimal conditions through the ANOVA numerical method.