not need to be cleaned between batches. The spray delivery piping is flushed with water through the nozzles onto carpet at the end of each day or production run. Hence NRD-342 in these lines does not go to waste. Spray lines operate for less than 20% of scheduled work days. Excess spray is recovered in catch trays under the process and returned to the mix tank for re-use after filtering. The company estimates that for an online facility operating for 1 week, less than 1 kg/week of active polysubstituted urethane would leave the process as waste. This figure is based on US experience on the environmental release of waste where no more than 2 kg waste/treatment would be generated per shift. The figure for Australian conditions is less due to the smaller scale of production lines and the mixing tanks used in Australia. The generated waste will be co-mingled with other plant aqueous- based wastes. diluted and directed via closed sewage lines to the local municipal sewage treatment plant for disposal. The total effluent flow from a carpet manufacturer would be 1 - 2.5 million litres per week. Therefore, the concentration of active polysubstitued urethane released into the sewer is < 1 ppm. Fate The company states that the polymer is non-volatile and insoluble in water and therefore no measurable losses would be expected to occur through volatility or leaching. Leaching of the polymer is unlikely as waste will not be disposed of to landfill. Biological oxygen demand (BOD) determination gave a BOD value that was below detection. This result indicates the polymer is not readily biodegradable. When the polymer is discharged to the sewer it is unlikely to biodegrade. The structure of the polymer suggests it may undergo hydrolysis, but whether it would under environmental conditions remains unclear. Once the polymer has been applied to the carpet it is unlikely to move off the surface. The chemical forms a very thin coating on the fibre. The polymer has a very polar backbone and has strong interactions with the fibre matrix. The company states that bonding is strong enough to withstand subsequent carpet processing which can include heating, chemical scouring and
not need to be cleaned between batches. The spray delivery piping is flushed with water through the nozzles onto carpet at the end of each day or production run. Hence NRD-342 in these lines does not go to waste. Spray lines operate for less than 20% of scheduled work days. Excess spray is recovered in catch trays under the process and returned to the mix tank for re-use after filtering. The company estimates that for an online facility operating for 1 week, less than 1 kg/week of active polysubstituted urethane would leave the process as waste. This figure is based on US experience on the environmental release of waste where no more than 2 kg waste/treatment would be generated per shift. The figure for Australian conditions is less due to the smaller scale of production lines and the mixing tanks used in Australia. The generated waste will be co-mingled with other plant aqueous- based wastes. diluted and directed via closed sewage lines to the local municipal sewage treatment plant for disposal. The total effluent flow from a carpet manufacturer would be 1 - 2.5 million litres per week. Therefore, the concentration of active polysubstitued urethane released into the sewer is < 1 ppm. Fate The company states that the polymer is non-volatile and insoluble in water and therefore no measurable losses would be expected to occur through volatility or leaching. Leaching of the polymer is unlikely as waste will not be disposed of to landfill. Biological oxygen demand (BOD) determination gave a BOD value that was below detection. This result indicates the polymer is not readily biodegradable. When the polymer is discharged to the sewer it is unlikely to biodegrade. The structure of the polymer suggests it may undergo hydrolysis, but whether it would under environmental conditions remains unclear. Once the polymer has been applied to the carpet it is unlikely to move off the surface. The chemical forms a very thin coating on the fibre. The polymer has a very polar backbone and has strong interactions with the fibre matrix. The company states that bonding is strong enough to withstand subsequent carpet processing which can include heating, chemical scouring and
NA12FR.docx