Off-Stream Detention Design for Storm-Water Management
AbstractA detention basin is designed for storm-water quantity and quality controls. An in-stream basin is often located on a widened floodplain, whereas an off-stream basin can be part of open space in a parking lot, park, or sport field. The inflow channel associated with an off-stream basin is allowed to carry its base flow not to exceed the downstream capacity. When the inflow channel is full, the excess flood water is diverted into the off-stream basin through the side weir. During the flood recession, the equalizer conduit drains the basin flow back to the channel. In this study, the rational volumetric method was expanded from in-stream to off-stream detention design. The required off-stream detention volume is maximized by the rainfall event longer than the time of concentration of the tributary area. In comparison, the off-stream detention volume can be significantly less than an in-stream, depending on the flow-through capacity in the downstream channel. This paper presents a design procedure to...
CLOSING THE FLOODGATES
The White Rock Creek basin in Dallas and Collin Counties, is one of Texas’ most crucial resources. While large tracts of undeveloped land in Collin County remain under agricultural or open space use, other land is quickly being converted for residential and commercial projects. Within the basin runs the White Rock Creek, a major tributary of the Trinity River, which drains 136 sq mi. A flood plain management study of the creek--a joint effect between the cities of Plano and Dallas--was commissioned and included 60 mi of White Rock Creek and 33 tributaries in Dallas and Plano. Ultimately, a $7.8 million flood plain management plan was approved by the Dallas City Council in June 1988, and an $18.3 million plan was approved by the Plano in April 1989. Perhaps more significant, the Texas study featured several innovative flood plain management techniques, including a global positioning system; 3-D digital mapping and topography; a Geographic Information System with remote sensing; satellite surveying; and CADD maps. During the White Rock Creek study, these technologies showed potential for reducing manpower needs and improving accuracy for future flood plain management studies.
Techno-economic analysis of chemical looping combustion with humid air turbine power cycle
Abstract Power generation from fossil fuel-fired power plant is the largest single source of CO2 emission. CO2 emission contributes to climate change. On the other hand, renewable energy is hindered by complex constraints in dealing with large scale application and high price. Power generation from fossil fuels with CO2 capture is therefore necessary to meet the increasing energy demand, and reduce the emission of CO2. This paper presents a process simulation and economic analysis of the chemical looping combustion (CLC) integrated with humid air turbine (HAT) cycle for natural gas-fired power plant with CO2 capture. The study shows that the CLC–HAT including CO2 capture has a thermal efficiency of 57% at oxidizing temperature of 1200 °C and reducer inlet temperature of 530 °C. The economic evaluation shows that the 50 MWth plant with a projected lifetime of 30 years will have a payback period of 7 years and 6 years for conventional HAT and CLC–HAT cycles respectively. The analysis indicates that CLC–HAT process has a high potential to be commercialised.