Integrated Assessment of Environmental and Economic Performance of Chemical Products Using Analytic Hierarchy Process Approach

With the increasing public consciousness on environmental issues, chemical products and process de-signs require simultaneous satisfaction and compromise of environmental and economical requirements. To fulfill the two conflicting while complementary objectives, a systematic approach for life cycle design of a chemical product is proposed in this article. Multiattribute decision-making is adopted in a trade-off consideration of both technical economical evaluation and environmental impacts assessment using the analytic hierarchy process (AHP) approach. On the basis of an evaluation of the relative importance of the criteria multicriteria decision making is performed. In this study, an AHP model is used to derive single a criteria score by analyzing the environmental im-pact and life cycle cost of a product, respectively. And a fluctuant weight analysis is put forth to calculate the inte-grated index of the product to enable products to be ranked or selected intuitionally and conveniently. The proposed AHP model has been applied to a case study, a comparative study on chamber cleaning with NF3 and C2F6. The re-sults show that the proposed AHP model is capable of providing a rational and relevant evaluation.

Structure-Property Relationships and Models of Controlled Drug Delivery of Biodegradable Poly (D, L-lactic acid) Microspheres

An oil-in-water (O/W) solvent evaporation method was used to prepare biodegradable microspheresbased on poly(D,L-lactic acid) (PLA). Nifedipine, a hydrophobic drug, was chosen as a model molecule in the studyof drug entrapment and release. Effect of preparation conditions on the size, morphology, drug loading, and releaseprofiles of micropheres was investigated. Based on in vitro release experimental findings, a diffusion/dissolutionmodel was presented for quantitative description of the resulting release behaviors and drug release kinetics fromPLA microspheres analyzed. The mathematical models were used to predict the effect of microstructure on theresulting drug release. It provided an approach to determine the suitable structure parameters for microspheres toachieve desired drug release behaviors.

A Genetic Algorithm-based Approach to Scheduling of Batch Production with Maximum Profit

The optimal scheduling of multi-product batch process is studied and a new mathematics model targeting the maximum profit is proposed, which can be solved by the modified genetic algorithm (MGA) with mixed coding (sequence coding and decimal coding) developed by us. In which, the partially matched cross over (PMX) and reverse mutation are used for the sequence coding, whereas the arithmetic crossover and heteropic mutation are used for the decimal coding. In axidition, the relationship between production scale and production cost is analyzed and the maximum profit is always a trade-off of the production scale and production cost. Two examples are solved to demonstrate the effectiveness of the method.

Process Development and Design of Chlorine Dioxide Production Based on Hydrogen Peroxide

This paper presents a process development and design of chlorine dioxide production based on hydrogen peroxide. The process is characterized by cleaner production, high efficiency, and waste minimization. Optimization of process conditions, selection of equipment, and experiment of recycle of waste acid are carried out. The process design is realized in consideration of several aspects such as operation, material, equipment design and safety. An industrialized process flowsheet is developed according to experiment. A pilot testing is carried out to confirm the lab results. Process design of chlorine dioxide production based on hydrogen peroxide is realized.

Highly Efficient,Green Oxidation of Alcohols Using Novel Heterogeneous Ruthenium Catalyst

MnFe1.4Ru0.45Cu0.15O4 was an effective heterogeneous catalyst for the oxidation of various types of alcohols to the corresponding carbonyl compounds using atmospheric pressure of oxygen under mild conditions. Furthermore, this catalyst was also effective towards alcohol oxidation using water as solvent instead of toluene.

Influence of Initiator on Synthesis and Properties of Polyurethane-acrylate Hybrid Emulsion

The prepolymer polyurethanes （PUs） based on isophorone diisocyanate （IPDI）, poly（propylene glycol） （PPG）, 1,4-butanediol （BDO） and dimethylopropionic acid （DMPA） were synthesized at 75-80 ℃ for 7-8 hours, using dibutyltin dilauate （DBTDL） as catalyzer, and polyurethane-acrylate hybrid emulsion was prepared after methyl methacrylate （MMA） was polymerized, using potassium persulfate and azobisisobutyronitrile （AIBN） as initiator, respectively. The influences of these factors such as the kind of initiator, the feed method of initiator and the addition of initiator on properties of polyurethane-acrylate were studied. The FTIR and GPC of aqueous polyurethane were analyzed. The FTIR spectra show that the degree of microphase-separate between the soft segments and rigid segments is high. The analysis of molecular weights stated that molecular weights increased most significantly after amine was added. The experimental results reveal that the appearance of emulsion is excellent, the film is harder and the water absorption radio of the film is less when oil-solubility AIBN is used as initiator. The semi-continuous can increase the molecular weight of polymer and the optimum amount of the initiator was 3% for MMA.

Design and performance test of miniature capillary pumped loop for electronics cooling

Considering two characteristics of compact heat dissipation room and high heat flux, a novel miniature capillary pumped loop (MCPL) for electronics cooling was proposed. MCPL consists of evaporator, condenser, vapor and liquid line dissipates heat by boiling and condensation of working fluids with no extra power consumption. Working fluid circulation is ensured by vapor pressure and capillary head. Saturated wick screens vapor and liquid, and ensures one-way flow of working fluid with no extra valve. In order to promote heat dissipation capacity of MCPL, the intensified boiling and condensation structures are embedded into evaporator and condenser respectively, which are useful to increasing boiling and condensation efficiency. Startup and run characteristics are tested by experiments in the condition of different power inputs and working fluids. MCPL is capable of dissipating 80 W of thermal energy and keeping the bottom substrate temperature of evaporator at 80 ℃.

Selective Oxidation of n-Butane over VPO Catalyst Modified by Different Additives

A series of vanadyl pyrophosphate catalyst （VPO） modified by different additives have been prepared with the aim to study the performance for selective conversion of n-butane to maleic anhydride（MA）. The addition of various promoters improved the catalytic performance remarkably on both activity and selectivity. The correlation of activity and selectivity of the catalysts with their structure has been discussed. The increase in BET surface areas and surface redox sites leads to an enhanced activity. However, good selectivity can only be obtained on those surfaces with suitable surface acid sites.

A Multi-layer Information Integration Platform for Chemical Process Operation Systems

In the process industry, automation and process control systems are widely implemented, information integration is however far away from satisfactory. It remains a hard job for senior managers to make decisions based on the plant-wide real-time integrated information. This paper proposes a multi-layer information integration platform. In the data integration level, the standard for the exchange of product (STEP) and the extensible markup language (XML) are used to unify these data of the chemical process. In the model integration level, the models are integrated by using the neutral model repository and CAPE-OPEN. In the integration of process task, the common object request broker architecture (CORBA) is used as the communication mediator. The XML is taken as the data standard. A uniform information platform is thus constructed and realized. The proposed information integration platform is satisfactorily implemented to solve the Tennessee Eastman (TE) problem.

Modeling and analysis of oil shale refinery process with the indirectly heated moving bed

China is rich of oil shale as one of alternative fossil energy resources.The exploitation and utilization of oil shale are strategically important in alleviating the shortage of oil and gas resources in China.However,low utilization rate of raw material,low oil yield,and high content of heavy components in the oil are the main problems in current Fushun type oil shale refinery technology.An indirectly heated moving bed is developed to de-bottleneck Fushun type technology.The oil shale refinery process with the indirectly heated moving bed is modeled and simulated in this work.Based on the simulation,a techno-economic analysis is performed and compared with the conventional Fushun oil shale refinery process.Results show that:for a shale refinery of 3.0 Mt/y scale,375 t/h oil shale retorting requires 149.6 MW of heat,in which 60%of the heat is produced by combustion of the oil shale pyrolysis gas,while remaining 40%from the coal gasified gas.In consideration of investment and operation,the cost of product shale oil of the new process is 2636 CNY/t,which is 12%lower than that of the conventional Fushun refinery process.This benefit comes from higher utilization of raw material and oil yield of the new process.The competitive crude oil price of the indirectly heated moving bed refinery process is about 51$/bbl,while that of the Fushun refinery process is 58$/bbl.During 2017 year,the crude oil price fluctuates at around 50$/bbl,thus the new indirectly heated moving bed refinery process shows better economic competitiveness.

一种基于状态估计的间歇过程模型实时更新预测控制策略(英文)

Nonlinear model predictive control(NMPC) is an appealing control technique for improving the performance of batch processes, but its implementation in industry is not always possible due to its heavy on-line computation. To facilitate the implementation of NMPC in batch processes, we propose a real-time updated model predictive control method based on state estimation. The method includes two strategies: a multiple model building strategy and a real-time model updated strategy. The multiple model building strategy is to produce a series of sim-plified models to reduce the on-line computational complexity of NMPC. The real-time model updated strategy is to update the simplified models to keep the accuracy of the models describing dynamic process behavior. The me-thod is validated with a typical batch reactor. Simulation studies show that the new method is efficient and robust with respect to model mismatch and changes in process parameters.