2 research outputs found
Ranking pipes in water supply systems based on potential to cause discoloured water complaints
A novel concept to rank pipes based on the potential (risk) to cause discoloured water complaints when broken is presented. A fixed re-suspension velocity for all sediments was used previously to model sediment transport. However, there is always a risk of sediment re-suspension and discoloration, if the velocity caused by hydraulic disturbance is greater than the conditioning velocity- the maximum daily velocity historically experienced in a pipe before the disturbance. In a full scale system, five pipes of different diameters (99 - 222 mm) and locations (loop or open) were simulated to break (break main flow at 10L/s) and the hydraulic response was analysed using hydraulic software. The total affected length of the pipes where velocity was more than the conditioning velocity was used for ranking. In general, breakage of a smaller diameter pipe (100 mm diameter) caused more widespread disturbance. If proven in the field, the hydraulic software could be modified to rank pipes, making it easy for utilities to prioritise the pipe to replace or pay more attention
Superiority of date seed ash as an adsorbent over other ashes and ferric chloride in removing boron from seawater
Many desalination plants, especially those utilising seawater as feed water, have trouble in reducing boron levels to the drinking water standards. The objective of this study is to investigate the removal of boron from seawater using low cost methods: three fly ashes as adsorbents and ferric chloride. Parameters which could affect boron removal efficiency were investigated, including pH, reaction time, and liquid/solid (l/s) ratio. The results suggested that fruit (date seed) based ash had remarkably higher efficiency of boron removal (71%) than power plants fly ash, pine tree fly ash, and coagulants. The optimum removal efficiency was achieved with the date seeds ash at pH 7 and l/s of 5. The results from the study are of practical significance as the date seed ash is showinghighest removal efficiency at neutral pH. In particular, the considerable capability of date seed ash to remove boron at a neutral pH is important in reverse osmosis (RO) process, as it enables better membrane stability and minimal membrane scaling and subsequently renders low operating costs