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Solid cellulose-based radioactive wastes (CBW) constitutes in some cases, about 70% of the total solid low and intermediate level organic wastes originated from peaceful applications of nuclear technology in various fields of our life. Cesium-137 and cobalt-60 represent two of the most important radioisotopes spiking these waste categories. Both are serious contamination concerns due to their high energy gamma ray emitting (Cs-137 = 0.662 MeV and Co-60 = 1.17 and 1.33 MeV), besides 137 Cs is considered as one of long-lived isotopes (T 1/2 = 30.5 years). In this part of work, laboratory scale attempts were performed to follow bioaccumulation of Cs-137 and/or Co-60, found separately or together in a mixture of some solid CBW simulates. The process is based on the capability of Pleurotus pulmonarius to biodegrade the solid CBW simulates achieving acceptable weight reduction for the waste as well as reasonable bioaccumulation of the two isotopes from the spiked mixture, within their cells. Up to 134.95 and 41.1 kBq/kg (based on the dry weight of mushroom) were accumulated from Cs-137 and Co-60 respectively within a period of 54±3 days. It is worth mentioning that more than 54% weight reduction percent for the solid CBW simulates was acquired only due to a single cultivation process. Based on the data so far obtained, the bioremediation process for solid CBW based on the P. pulmonarius bioactivity seems to be simple, effective, and economical and can work where the other process cannot be applied.

For mills making paper with recovered fiber, removal of hydrophobic contaminants is essential for trouble-free operation of paper machines. Significant cost savings on paper machine operation can be achieved by reducing deposits, which results in better quality, reduced downtime, increased fiber yield, and reduced energy consumption. Bubble nucleation separation (BNS) is a relatively new process for removing hydrophobic particles. When vacu-um is applied to a slurry, dissolved gas bubbles nucleate on hydrophobic particles and drag them to the surface for easy removal. We constructed a 16-L batch unit to evaluate the effect of operating parameters on removal of hydro-phobic particles, using statistical design of experiments. These results were used to guide our design of a 16-L con-tinuous unit. We tested this unit on laboratory and mill samples. The removal of 60%–80% of hydrophobic particles was achieved with a low reject rate of < 2%. Following on this success, we built a 200-L pilot unit and tested it in our pilot plant. With promising results there, we installed the pilot unit at a commercial paper recycling mill. Over the course of several mill trials, we showed that it was possible to remove a considerable amount of suspended solids from paper machine white water with less than 2% rejects. Unfortunately, due to the unit only treating 50 L/min and the mill flow being 12000 L/min, we were not able treat a sufficient portion of the white water to know whether a large-scale implementation of BNS would improve paper machine runnability.

Building Information Modelling (BIM) is a technology that potential to increase effectiveness and productivity in projects. Implementing BIM in the project not only can simultaneously represent the physical modelling of a building but also can reduce waste and optimize time and resources as the aims of green construction. Nevertheless, unfortunately the level of BIM adoption in Indonesia is lower than other developing countries. The aim of this research is to analyse factors and barriers to implementing BIM to support green construction in Indonesia. This study uses a quantitative research method in a questionnaire survey of 20 construction projects in Indonesia to determine the factors driving BIM adoption and barrier to BIM adoption on construction projects in Indonesia. The result finds five factors driving the implementation of BIM in Indonesia i.e requirements from the government, BIM is believed to improve performance, BIM is believed better than existing method, technology and resources readiness, and support from top management. Despite the driving factors, the implementation of BIM also has barriers i.e lack of information, lack of BIM training for workers, reluctance to change, lack of owner requirement, and high the initial cost.