Operation Of Production Plant Research Articles

Multienzyme production by Bacillus velezensis strains isolated from fruit residues in submerged fermentation using triticale and sugarcane bagasse in the cultivation media

The production of multienzymes complex that could act in different raw materials is needed to improve the bioethanol production process. We isolated bacteria from vegetable residues, identified as Bacillus velezensis (UPF-B1 and UPF-B2), which were able to simultaneously produce amylolytic and cellulolytic enzymes. The enzyme complex was produced by submerged fermentation in a media containing whole-grain triticale flour and sugarcane bagasse at pH 5.5 without supplementation with micronutrient solutions, reducing the media's costs. The combined use of raw materials (triticale and sugarcane bagasse) led to higher enzymatic activities, which is important given the need for the availability of raw materials for the industrial operation of enzyme and bioethanol production plants. The enzymes produced by UPF-B1 showed their optimum at pH 5.0–5.5 and 40 ºC, and those produced by UPF-B2 at pH 5.0–5.5 and 30–50 ºC. The multienzyme complex produced by the strain UPF-B2 allows the hydrolysis in mild temperatures, near to those of fermentation processes, avoiding the need for thermophilic yeasts in the fermentation step, being a desirable option to be used in simultaneous saccharification and fermentation processes of bioethanol production.

Techno-Economic Analysis of the Production of Lactic Acid from Lignocellulosic Biomass

This study reports the results of an evaluation of the techno-economic feasibility of a biorefinery with an annual lactic acid production capacity of 100,000 metric tons using lignocellulosic biomass. Corn stover and miscanthus were considered as model feedstocks, and three different fermentation pathways involving bacteria, fungi, and yeast were compared with respect to their ability to convert biomass feedstocks to lactic acid. Equipment, raw materials, utilities and labor requirements, and lactic acid production costs were estimated. The minimum selling price (at a 10% internal rate of return) per metric ton of lactic acid produced from different feedstocks for lactic acid bacteria, fungi, and yeast-based pathways were in the range of USD 1243–1390, USD 1250–1392, and USD 993–1123, respectively, with lower costs for miscanthus. Lactic acid production using genetically engineered yeast strains can eliminate the need for the simultaneous neutralization and recovery of lactic acid, resulting in lower equipment, chemical, and utility requirements and lower lactic acid production costs. Lactic acid production costs were highly sensitive to the conversion rates of sugars into lactic acid, feedstock cost, production plant size, operation hours, and acid hydrolysis reactor costs. Improvements in process conditions and efficiencies and lower costs of equipment and consumables are necessary to utilize lignocellulosic biomass for lactic acid production at lower costs while remaining cost-competitive with respect to first-generation and petroleum-based feedstocks.

Liquid–Liquid Equilibria of Glycerol + Alcohol + Safflower Biodiesel Systems: Measurement and Modeling

Liquid–liquid equilibrium (LLE) for the biodiesel + glycerol + alcohol system is essential for the design, operation, process optimization, and economic evaluation of a biodiesel production plant. In this work, methyl and ethyl safflower biodiesels were produced from safflower (Carthamus tinctorius L.) seed oil. New LLE experimental datasets were obtained for the glycerol (1) + methanol/ethanol (2) + methyl/ethyl safflower biodiesel (3) systems at 298.15 and 318.15 K under atmospheric pressure. Binodal curves, tie-lines, distribution coefficients, and selectivity were determined. Data reliability was confirmed using the Othmer–Tobias correlation. LLE data were correlated with the UNIQUAC model satisfactorily, with deviations between 0.70 and 2.79% for all studied systems. The consistency of the estimated binary interaction parameters of the UNIQUAC model was ascertained. Finally, through process simulations in Aspen Hysys software, it was verified that the UNIFAC LLE model, along with the UNIQUAC model, can also be used adequately to describe the liquid–liquid behavior of biodiesel separators, provided that the biodiesel composition is accurately known.

Impact assessment of alternative fuels on production Cost, plant operation and Environment- case study of Indian cement industry

The cement industry is highly energy intensive, consuming ∼ 15% of total energy demand and responsible for 26% of total industrial CO2 emissions. With the world’s second-largest installed production capacity of 594.14 million tonnes, presently Indian cement industry is struggling with uncertainty in availability as well as the cost of fuel (coal & petcoke), forcing the industry to replace conventional fuels with Alternative Fuels (AFs). This study assesses the impact of AFs on production cost, environment, operation, and maintenance of Indian cement plants and highlights that utilization of AFs provides cost benefits, mitigates CO2 without any environmental issues, and is a holistic way of waste disposal. Jamming of the transfer chute & feeding chute to calciner is found to be a major operational problem contributing to 50 to 70% of system breakdown hours. This study recommends the utilization of AFs in the cement industry and further research to establish design parameters for a transfer chute that can handle the majority of AFs & their mix without jamming, flushing, and plugging issues.

Novel purification of oily process water from ethylene production at pilot scale

Ethane steam cracking to ethylene plants produce a large amount of organic sewage containing oil and suspended solids, which can lead to heat exchanger blockage and steam regeneration difficulties. Efficient treatment and recycling of process water is one of the keys to ensure a stable operation of ethylene production plant. The traditional multi-stage tandem process water treatment process has issues such as long treatment process, blockage of flow path by coke powder particles, and incomplete oil–water separation. Therefore, this study proposes a cooperative process combining medium particles extraction (MPE) and combined fibrous coalescence (CFC) technology to remove oil and turbidity in process water. Based on laboratory tests and analyses, a pilot test of process water purification with a flow rate of 1.6 m3/h was implemented. The results of the pilot test demonstrated that the process reduced the average oil content of process water from 606 to 18.4 mg/L and the average turbidity from 1213 to 7.9 NTU, with average separation efficiencies of 96.96 % and 99.35 %, respectively. Compared with current process water treatments, this approach provides a higher operational flexibility, better separation effect, and it is more environmentally friendly. This study provides a novel approach for a green and efficient treatment and recycling of process water.

Assessment of reinforcement learning applications for industrial control based on complexity measures

Abstract Machine learning and particularly reinforcement learning methods may be applied to control tasks ranging from single control loops to the operation of whole production plants. However, their utilization in industrial contexts lacks understandability and requires suitable levels of operability and maintainability. In order to asses different application scenarios a simple measure for their complexity is proposed and evaluated on four examples in a simulated palette transport system of a cold rolling mill. The measure is based on the size of controller input and output space determined by different granularity levels in a hierarchical process control model. The impact of these decomposition strategies on system characteristics, especially operability and maintainability, are discussed, assuming solvability and a suitable quality of the reinforcement learning solution is provided.

Research on the application of molecular simulation technology in enhanced oil-gas recovery engineering

In recent years, molecular simulations have received extensive attention in the study of reservoir fluid and rock properties, interactions, and related phenomena at the atomistic scale. For example, in molecular dynamics simulation, interesting properties are taken out of the time evolution analysis of atomic positions and velocities by numerical solution of Newtonian equations for all atomic motion in the system. These technologies assists conducting “computer experiments” that might instead of be impossible, very costly, or even extremely perilous to carry out. Whether it is from the primary oil recovery to the tertiary oil recovery or from laboratory experiment to field test, it is difficult to clarify the oil displacement flow mechanism of underground reservoirs. Computer molecular simulation reveals the seepage mechanism of a certain oil displacement at the microscopic scale, and enriches the specific oil displacement flow theory system. And the molecular design and effect prediction of a certain oil-displacing agent were studied, and its role in the reservoir was simulated, and the most suitable oil-displacing agent and the best molecular structure of the most suitable oil-displacing agent were obtained. To give a theoretical basic for the development of oilfield flooding technology and enhanced oil/gas recovery. This paper presents an overview of molecular simulation techniques and its applications to explore enhanced oil/gas recovery engineering research, which will provide useful instructions for characterizing the reservoir fluid and rock and their behaviors in various oil-gas reserves, and it greatly contribute to perform optimal operation and better design of production plants.

A Novel Method for Sensor Data Validation based on the analysis of Wavelet Transform Scalograms

Sensor data validation has become an important issue in the operation and control of energy production plants. An undetected sensor malfunction may convey inaccurate or misleading information about the actual plant state, possibility leading to unnecessary downtimes and, consequently, large financial losses. The objective of this work is the development of a novel sensor data validation method to promptly detect sensor malfunctions. The proposed method is based on the analysis of data regularity properties, through the joint use of Continuous Wavelet Transform and image analysis techniques. Differently from the typical sensor data validation techniques which detect a sensor malfunction by observing variations in the relationships among measurements provided by different sensors, the proposed method validates the data collected by a given sensor only using historical data collected from the sensor itself. The proposed method is shown able to correctly detect different types and intensities of sensor malfunctions from energy production plants.

Oil refinery sludge and renewable fuel blends as energy sources for the cement industry

Oil refinery sludges from tank bottoms, oil-water-solid separators and dissolved air-filtration range around 0.2 w% of crude oil processed and are classified as hazardous wastes. Worldwide data manifest large disparities in composition (10–20% hydrocarbons, 5–20% solids -including heavy metals- and water) and heating values. Treatment by landfarming/bioremediation, hazardous waste incineration, anaerobic digestion or disposal in hazardous waste landfills bears high costs and environmental impacts. Substitution of fossil fuels (petcoke) by refinery sludges in cement plants is investigated. Main impacts are quantified: energy efficiency and clinker production level, plant operation and capacity constraints, halogen presence in plant circuits, inclusion of alkalis and heavy metals in cement and atmospheric emissions. It is found that clinker losses may exceed one tonne clinker/tonne sludge. Environmental concerns, mainly increased NOx and Hg emissions, may restrict substitution. Guidelines are obtained for identifying efficient blends with renewable biogenic fuels (urban or agro-industrial biowaste). Blends of sludge from local refineries with renewable fuels are assessed for a local cement plant using about 1.65 × 105 tonnes fossil fuels/year (70% petcoke, 30% coal) to produce 1.5 × 106 tonnes clinker/year. Superior customer-tailored blends are identified that avert clinker losses, maintain operability and tolerable inclusions, reduce greenhouse gas emissions and improve atmospheric pollutant emissions.

Optimal production scheduling for smart manufacturers with application to food production planning

This paper aims at implementing an optimization technique in smart manufacturing applications for co-optimizing the operation of multiple production lines to supply the desired demand for multiple products. The proposed model, which is formulated as a mixed-integer linear programming (MILP) problem, minimizes the total manufacturing cost by co-optimizing the operation schedule of production lines. The proposed model implements several operating constraints of the production lines that include their energy consumption and associated costs, productivity, scrap rates, changeover duration, and labor costs. The proposed model is implemented on a sample manufacturer, where seven production lines with different operational constraints are optimized to manufacture six product types. In addition, the model is utilized to optimize the operation of a real-world food production plant with five lines and twelve different product types. The simulation results show that the proposed optimal scheduling model allows the manufacturers to enhance production efficiency and save on operation costs by co-optimizing the operation schedule of production lines. Sensitivity analyses are conducted to demonstrate the performance of the model in different demand levels, where the manufacturers are enabled to optimally schedule the production lines at minimum cost given the production demand.

Dynamic risk calculation model applied to gas compressor

Abstract The present article proposes to apply a Risk-Based Maintenance methodology in a gas compression system. This risk calculation is based on a semi-quantitative mathematical model that uses the interdependence of process variables and predictive maintenance data applied in a Condition-Based Maintenance methodology, in order to obtain the calculation of the dynamic risk. This promotes a review of maintenance and reliability strategies proactively in real time. The dynamic risk applied to the system involves the interface of predictive maintenance and process variables with the reliability and risk analyses of the system. This value, which is associated with the financial aspects, safety, people and environment, can be compared to the tolerable risk of production plant operation, providing operation or maintenance decisions. An example demonstrates the integration of process and maintenance data using this model methodology for a gas compression system. This framework can be applied to evaluate the integrity of systems, providing critical risk-based information for the maintenance and operation teams, assisting then in the mitigation of failures in the production systems.

The Production of the Isotope 15N by Isotopic Exchange in Nitrox System at Pressure

The operation of 15N production plant at pressure of 0.7 +/- 0.05 bar in stable conditions at total reflux and in production is demonstrated. The 10M HNO3 flows used in the primary column were 6.6 L/h and 6.0 L/h, 47, respectively 33% higher than that of atmospheric pressure (4.5 L/h) and corresponding flow rates of the same column were 3.12 mL/cm2. min, respectively 2.83 mL/cm2.min for operation at pressure, compared to 2.12 mL/cm2�.min at atmospheric pressure. The 10M HNO3 flows used in the final column were 324 mL/h and 264 mL/h, 62, respectively 32 % higher than that of the atmospheric pressure (200 mL/h) and flow rates of that column were: 3.05 mL/cm2.min, respectively 2.49 mL/cm2.min, compared to 1.86 mL/cm2�.min for atmospheric pressure operation. The HETP values are lower for both separation columns operated at pressure and higher 10M HNO3 flow rates, that being an argument in the favour of operation the 15N production plant by isotopic exchange in Nitrox system at pressure. The nitrogen enriched in 15N losses in the waste sulphuric acid, evacuated at the bottom of product refluxer stage II, were : 5.18 -10.58 ppm of feeding with 10M HNO3 of the plant. Any losses of nitrogen enriched in 15N represent an additional uncontrolled production, which diminishes the production of 15N plant. In the case of operation at pressure the flows of H15NO3 extracted as plant product are higher than those corresponding to atmospheric pressure because the nitric acid solution is chemically equilibrated with nitrogen oxides at the operation pressure and temperature. At a pressure of 1 atm. in the 15N production plant the nitrogen content of nitric acid solution would be 10.919M instead of 10M.

An optimization model for site-wide scheduling of coupled production plants with an application to the ammonia network of a petrochemical site

This contribution presents the modeling and optimization of the operation of production plants that are coupled via distribution networks and applies it to a part of the petrochemical production site of INEOS in Köln in Germany. The problem is formulated as a mixed-integer linear problem and solved to generate an optimal monthly plan for a set of plants, tanks, and loading/unloading facilities, while respecting various constraints arising from technical limitations, physical couplings between the plants, production targets, and the schedule for import and export across the company borders via ships and trains. The optimization problem takes into account varying energy prices, the influence of the ambient temperature on the processes, and the inventory management for different types of storages. We solve the optimization problem for the particular case and compare the results for a 1 month scenario to recorded data and show that a significant energy saving potential exists. We discuss the current limitations and outline potential improvements in the context of the application of the optimization model to optimal site planning that leads to an improved coordination of the production in the process industries.

Process design and techno-economical analysis of hydrogen production by aqueous phase reforming of sorbitol

The present study was focused on detailed sorbitol aqueous phase reforming (APR) process design. Aspen HYSYS software was used to design a 500kg/h hydrogen production plant operation with sorbitol syrup as a feedstock. For reactor modelling a complex reaction network was taken into account along with phase equilibrium simulations which determined to have a significant impact on the total process heat due to possibility of water evaporation. The model was adjusted and verified using the experimental data with 1%Pt/Al2O3. The process optimization has included several conceptual improvements such as middle pressure steam co-generation and hot water recycle which can significantly decrease the operation costs. The total costs of hydrogen were estimated as 12.97$/kg, where feedstock costs take the major contribution of 91.8%. The most feasible way of making APR economical attractive is production of polyols from the lignocellulosic biomass.

Modelling and dynamic simulation of a large MSF plant using local phase equilibrium and simultaneous mass, momentum, and energy solver

Abstract Seawater desalination is an important method for producing fresh water, a critical resource in many areas of the globe. Multi-stage flash distillation (MSF) is a leading technology within the thermal desalination field. Mathematical modelling and simulation provides a means to enhance engineering and operation of complicated production plants. This paper presents a new method for one-dimensional modelling and dynamic simulation of thermal desalination processes. The approach combines the simultaneous mass, momentum, and energy solution, local phase equilibrium by Rachford-Rice equation, and rigorous calculation of the seawater properties as function of temperature, pressure and salinity. A brine recycling MSF plant was modelled as a case study, presenting advanced and unpublished simulated features and transients. The successful results suggest that the method presented is a competent approach for dynamic simulation of thermal desalination processes.

Modules in process industry − A life cycle definition

The chemical and biochemical industry has to face the challenges of globalization, short product cycle times and volatile markets. Therefore, the lead time of development projects has to be shortened. Modules and module-based plant design are widely discussed to enable shorter time-to-market by reuse of engineering effort and standardization. In this paper general requirements on modules in process engineering and modules for particular applications in the chemical and biochemical industry are reviewed. This includes the impact of modules on the planning process and examples of realized modular equipment concepts. Based on this, a general terminology definition of ‘modules’ and of specific module types for the process industry is presented, whereas modules on various ‘aggregation levels’ are accounted. A ‘block representation frame’ stores information and tracks information fluxes along the whole process and plant life cycle and on different ‘realization levels’ from laboratory studies over miniplant validation to production plant design and operation.

On increasing the efficiency of multistage extractive separation of metals

Two possibilities have been considered for improving the operation of a cascade of mixer-settler extractors, i.e., a new connection scheme between process vessels and a new chromatographic mode for carrying out the process. Studies on cobalt and nickel separation have been performed using an experimental setup and technological solutions taken from cobalt production with Cyanex extractants. A comparison of results obtained using the experimental setup with the data of an production plant operation has shown that the new scheme results in a marked increase in the productivity and efficiency of metal separation in a cascade of mixer-settler extractors. Based on numerical studies, it has been found that the cyclic process in the chromatographic mode allows one to separate a multicomponent mixture using a single operation.

APPLICATION OF TECNOMATIX PLANT SIMULATION FOR MODELING PRODUCTION AND LOGISTICS PROCESSES

The main objective of the article was to present the possibilities and examples of using Tecnomatix Plant Simulation (by Siemens) to simulate the production and logistics processes. This tool allows to simulate discrete events and create digital models of logistic systems (e.g. production), optimize the operation of production plants, production lines, as well as individual logistics processes. The review of implementations of Tecnomatix Plant Simulation for modeling processes in production engineering and logistics was conducted and a few selected examples of simulations were presented. The author’s future studies are going to focus on simulation of production and logistic processes and their optimization with the use of genetic algorithms and artificial neural networks.

Monitoring of Emulsion Polymerisation Processes using Ion Mobility Spectrometry—A Pilot Study

AbstractOnline monitoring of monomer concentrations in (semi‐) batch emulsion polymerisation reactors is important for safe and cost‐efficient operation of production plants. In the present pilot study, ion mobility spectrometry was applied for monitoring the concentration during emulsion polymerisation of vinyl acetate (VA) using UV light for ionisation of the headspace of a continuous sample flow. Satisfactory sensitivity for online process monitoring of the monomer concentration in the reactor was observed (LOD 400 ng · L−1 air, equivalent to <1%). Furthermore, it is possible to discriminate between VA and other common monomers [butyl acrylate (BA), methyl methacrylate (MMA)]. Using the more efficient β‐radiation ionisation, monomer concentration could be measured even in the final latex as a measure of the final product properties.magnified image

Model Based Operation of Polymer Processes – What has to be Done?

AbstractSummary: In the last two decades, simulation technology had a large influence on process industries. Today, modern numerical methods, powerful personal computers and convenient software packages facilitate the solution of complex chemical engineering problems on the basis of rigorous process models at every office workplace. However, although in many cases process models are available from the process design step, model based operation of production plants can only be found rarely. Changing this situation would significantly contribute to the cost effectiveness of many production plants.This contribution focuses on the model based operation of polymer processes which are for some reasons not perfectly suited for model application: Polymer process models tend to be complex, meaningful online measurements are expensive and not always reliable, many polymer processes are performed in batch instead of steady‐state and for most polymer plants, due to the smaller throughput, the economic impact of model application is much smaller than compared to for instance a steam cracker.When model based operation is considered, it has to be recognized that there is not one single approach but many different alternatives of which maybe only a single one will lead to a sustainable economical improvement of the process. From many successfully applied concepts for model based plant operation it can be clearly identified that always trying to implement the most complex solution (e.g. nonlinear closed‐loop online optimization) is neither possible nor reasonable but that plant specific tailor‐made solutions are necessary.