Maximising heat recovery in batch processes via product streams storage and shifting

In a batch process, either direct or indirect heat integration may be employed. The former involves direct heat transfer from hot to cold process streams. In the latter, heat from a hot process stream is first transferred to an intermediate fluid where the heat is stored until it is finally transferred to a cold stream. Storage of product streams allows direct heat integration to be delayed, thereby providing an opportunity for energy conservation while avoiding the use of an intermediate fluid. This paper presents a new methodology for batch heat integration that involves the direct storage of product streams within the procedure to set the minimum utility targets. Application of the proposed methodology on illustrative examples demonstrates that significant energy reduction can be achieved by shifting product streams on the time scale. Potential reductions of 33.2% cold utility and 45.1% hot utility were estimated for the first example when the product stream was stored. Similarly, reductions of 3.5% cold utility and 6.5% hot utility were observed for a two-product batch plant when the cooling requirement for one of the products was shifted on time scale. (C) 2015 Elsevier Ltd. All rights reserved

The role of wetlands in mitigating the effect of climate change in Nigeria

This chapter reviews the place of wetlands in climate change within the overall frame of environmental resource planning. This is against the background of the importance of wetlands as environmental resources which have been described as the kidneys of the landscape as a result of its hydrological and chemical functions and as atmospheric carbon sinks which stabilize the climate. The study reviewed mitigating and adapting measures in literatures that may be adopted in Nigeria in order to enhance the potentials of wetland resources in the country. The chapter asserts that the declining environmental resource base of the country is mainly due to anthropogenic influences because wetlands in Nigeria are largely exploited for economic gains and are basically used for subsistence living or for physical development. Statistical data from the government shows that 60 % of Nigerian population depend solely on the natural resource base and are engaged in farming, cattle rearing, and fishing. This chapter provides measures which include restoration programs, reduction of further disturbance on wetlands, and legislative and policy formulations for protecting wetlands which are considered appropriate and can contribute greatly in mitigating climate change when properly harnessed as a way forward toward climate change mitigation and adaptation