The Design and Control of Distillation Column with Side Reactors for Chlorobenzene Production

The distillation column with side reactors (SRC) can overcome the temperature/pressure mismatch in the traditional reactive distillation, the column operates at temperature/pressure favorable for vapor-liquid separation, while the reactors operate at temperatures/pressures favorable for reaction kinetics. According to the smooth operation and automatic control problem of the distillation column with side reactors (SRC), the design, simulation calculation and dynamic control of the SCR process for chlorobenzene production are discussed in the paper. Firstly, the mechanism models, the integrated structure optimal design and process simulation systems are established, respectively. And then multivariable control schemes are designed, the controllability of SRC process based on the optimal steady-state integrated structure is explored. The dynamic response performances of closed-loop system against several disturbances are discussed to verify the effectiveness of control schemes for the SRC process. The simulating results show that the control structure using conventional control strategies can effectively overcome feeding disturbances in a specific range.

Top-K Query Framework in Wireless Sensor Networks for Smart Grid

The smart grid has caught great attentions in recent years, which is poised to transform a centralized, producer-controlled network to a decentralized, consumer- interactive network that＇s supported by fine-grained monitoring. Large-scale WSNs （Wireless Sensor Networks） have been considered one of the very promising technologies to support the implementation of smart grid. WSNs are applied in almost every aspect of smart grid, including power generation, power transmission, power distribution, power utilization and power dispatch, and the data query processing of ＇WSNs in power grid＇ become an hotspot issue due to the amount of data of power grid is very large and the requirement of response time is very high. To meet the demands, top-k query processing is a good choice, which performs the cooperative query by aggregating the database objects＇ degree of match for each different query predicate and returning the best k matching objects. In this paper, a framework that can effectively apply top-k query to wireless sensor network in smart grid is proposed, which is based on the cluster-topology sensor network. In the new method, local indices are used to optimize the necessary query routing and process intermediate results inside the cluster to cut down the data traffic, and the hierarchical join query is executed based on the local results.Besides, top-k query results are verified by the clean-up process, and two schemes are taken to deal with the problem of node＇s dynamicity, which further reduce communication cost. Case studies and experimental results show that our algorithm has outperformed the current existing one with higher quality results and better efficiently.

Study on Water Pollution Control of Huaihe River and Countermeasures

Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is ＂chronic＂ and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.