Modelling and Advanced Control of Industrial Wood Waste Boilers

2003 ◽  
Author(s):  
Richard H. Meeker ◽  
Majura F. Selekwa
Keyword(s):  
Fuel Consumption ◽  
Energy Savings ◽  
Paper Industry ◽  
Electric Utility ◽  
Wood Waste ◽  
Net Energy ◽  
Robust Controller ◽  
Pulp Paper ◽  
Common Control ◽  
Waste Incinerators

This paper describes recent work to develop an improved approach to control of wood-waste fired boilers, and, in particular, bark-fired boilers commonly in operation in the pulp and paper industry. A brief review of the process and control requirements and common control methods currently employed is followed by a discussion of development of a first-principles boiler model suitable for use in development of a robust controller. A simple nonlinear model for the boiler is developed and used for designing a robust controller that offers better performance in terms of tracking the desired reference point in the face of uncertain variations in the system parameters. The objective of the proposed controller is to increase the responsiveness to load changes, reduce the variability of controlled parameters, and improve efficiency of the boiler (reducing fuel consumption). With hundreds of these boilers in operation at large pulp, paper, and paperboard mills in the U.S., potential net energy savings through efficiency improvement and reduced fuel consumption are substantial, with likely side benefits of reduced emissions and possible reapplication of developments to fossil-fired electric utility boilers, waste incinerators, hog fuel, and biomass boilers.

scholarly journals Optimal Control for a Hydraulic Recuperation System Using Endoreversible Thermodynamics

2021 ◽  
Vol 11 (11) ◽  
pp. 5001
Author(s):  
Robin Masser ◽  
Karl Heinz Hoffmann
Keyword(s):  
Optimal Control ◽  
Fuel Consumption ◽  
Energy Savings ◽  
Combustion Engine ◽  
Mechanical Energy ◽  
Hydraulic Systems ◽  
Commercial Vehicles ◽  
Hybrid Drive ◽  
Environmental Considerations ◽  
Onboard System

Energy savings in the traffic sector are of considerable importance for economic and environmental considerations. Recuperation of mechanical energy in commercial vehicles can contribute to this goal. One promising technology rests on hydraulic systems, in particular for trucks which use such system also for other purposes such as lifting cargo or operating a crane. In this work the potential for energy savings is analyzed for commercial vehicles with tipper bodies, as these already have a hydraulic onboard system. The recuperation system is modeled based on endoreversible thermodynamics, thus providing a framework in which realistic driving data can be incorporated. We further used dissipative engine setups for modeling both the hydraulic and combustion engine of the hybrid drive train in order to include realistic efficiency maps. As a result, reduction in fuel consumption of up to 26% as compared to a simple baseline recuperation strategy can be achieved with an optimized recuperation control.

scholarly journals An energy-efficient metro speed profiles for energy savings: application to the Valencia metro

2016 ◽  
Author(s):  
Ignacio Villalba Sanchis ◽  
Pablo Salvador Zuriaga
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Economic Cost ◽  
Rolling Stock ◽  
Net Energy ◽  
General Terms ◽  
Proposed Model ◽  
Single Vehicle ◽  
Reduction Of Energy Consumption ◽  
Actual Energy Consumption

Nowadays one of the main priorities for metro line operators is the reduction of energy consumption, due to the environmental impact and economic cost. In order to achieve this objective different strategies can be applied, normally focused into rolling stock, infrastructure and/or operation. Considering short-term measures and related to the traffic operation strategies, different approaches are being researched. One of the most effective strategy which reduce net energy consumption is the use of efficient driving techniques. These techniques produces a speed profile between two stations that requires the minimum net energy consumption, without degrading commercial running times or passenger comfort. In this paper, a computer model for calculating the metro vehicles speed profiles minimizing the energy consumption was developed. The equations considered in the model represent the behavior of a single vehicle operated under manual driving, subject to different constraints such as the headway, cycle time, distances and acceleration limits. The proposed model calculates different commands to be systematically executed by the driver. The resulting simulator has been tuned by means of on board measurements of speed, accelerations and energy consumption obtained along different lines in Metro de Valencia network. For this purpose, different scenarios are analyzed to assess the achievable energy savings. In general terms and comparing with the actual energy consumption, the solutions proposed can reduce the net energy consumption around 19%.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3774

Air Layer on Superhydrophobic Surface for Frictional Drag Reduction

2020 ◽  
Vol 64 (02) ◽  
pp. 118-126
Author(s):  
Bradley C. Peifer ◽  
Christopher Callahan-Dudley ◽  
Simo A. Makiharju
Keyword(s):  
Drag Reduction ◽  
Superhydrophobic Surface ◽  
Energy Savings ◽  
Surface Hydrophobicity ◽  
Net Energy ◽  
Frictional Drag ◽  
Gas Flux ◽  
Still Images ◽  
Painted Surface ◽  
Air Layer Drag Reduction

We examined the feasibility of combining a superhydrophobic surface (SHS) and air layer drag reduction (ALDR) to achieve the frictional drag reduction (DR) shown achievable with traditional ALDR, but at a reduced gas flux to increase the achievable net energy savings. The effect of a commercial SHS coating on the gas flux required to maintain a stable air layer (AL) for DR was investigated and compared with that of a painted non-SHS at Reynolds numbers up to 5.1 X 106. Quantitative electrical impedance measurements and more qualitative image analysis were used to characterize surface coverage and to determine whether a stable AL was formed and maintained over the length of the model. Analysis of video and still images for both the SHS and painted surface gives clear indications that the SHS is able to maintain AL consistency at significantly lower gas flux than required on the non-SHS painted surface. Hydrophobicity of the surfaces was characterized through droplet contact angle measurements, and roughness of all the flow surfaces was measured. The results from these preliminary experiments seem to indicate that for conditions explored (up to Rex = 5.1 X 106), there is a significant decrease in the amount of gas required to establish a uniform AL (and hence presumably achieve ALDR) on the SHS when compared with a hydraulically smooth painted non-SHS.

Environmental Protection in the United States Pulp, Paper, and Paperboard Industry: An Overview of Regulation of Wastewater Under the U.S. Clean Water Act

1988 ◽  
Vol 20 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Rebecca W. Hanmer
Keyword(s):  
United States ◽  
Environmental Protection ◽  
Environmental Protection Agency ◽  
Clean Water Act ◽  
Paper Industry ◽  
Oxygen Demand ◽  
The United States ◽  
Pulp And Paper ◽  
Clean Water ◽  
Pulp Paper

The pulp, paper, and paperboard industry in the United States is the larqest industrial user of water with half of the facilities discharging wastewater directly to our Nation's waters. The major pollutants of concern have historically been the conventional pollutants: biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. Biological treatment systems are currently employed to reduce these pollutants. Sludges generated by these treatment systems have been categorized as nonhazardous and are generally landfilled. Under the Clean Water Act, the Environmental Protection Agency (EPA) has promulgated all the reguired regulations for this industry. The national regulations are applied to individual pulp and paper mills through permits issued by EPA Regional or State staff. Permit limits can be written that are more restrictive than the national regulations to protect local water guality. In its current projects concerning the pulp and paper industry, EPA is focusing on the reduction of toxic pollutants. The Agency is conducting a joint EPA/industry program to study dioxin discharges at bleached kraft mills. The Agency will also undertake a comprehensive review of the pulp and paper regulations in 1988.

scholarly journals Catalytic Fast Pyrolysis of Lignin Isolated by Hybrid Organosolv—Steam Explosion Pretreatment of Hardwood and Softwood Biomass for the Production of Phenolics and Aromatics

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 935 ◽  
Author(s):  
Ioannis Charisteidis ◽  
Polykarpos Lazaridis ◽  
Apostolos Fotopoulos ◽  
Eleni Pachatouridou ◽  
Leonidas Matsakas ◽  
...  
Keyword(s):  
Steam Explosion ◽  
Paper Industry ◽  
Fast Pyrolysis ◽  
Hydrolysis Lignin ◽  
Oil Composition ◽  
Catalytic Fast Pyrolysis ◽  
Pulp Paper ◽  
Polycyclic Aromatic ◽  
Alkyl Phenols ◽  
Biomass Sugars

Lignin, one of the three main structural biopolymers of lignocellulosic biomass, is the most abundant natural source of aromatics with a great valorization potential towards the production of fuels, chemicals, and polymers. Although kraft lignin and lignosulphonates, as byproducts of the pulp/paper industry, are available in vast amounts, other types of lignins, such as the organosolv or the hydrolysis lignin, are becoming increasingly important, as they are side-streams of new biorefinery processes aiming at the (bio)catalytic valorization of biomass sugars. Within this context, in this work, we studied the thermal (non-catalytic) and catalytic fast pyrolysis of softwood (spruce) and hardwood (birch) lignins, isolated by a hybrid organosolv–steam explosion biomass pretreatment method in order to investigate the effect of lignin origin/composition on product yields and lignin bio-oil composition. The catalysts studied were conventional microporous ZSM-5 (Zeolite Socony Mobil–5) zeolites and hierarchical ZSM-5 zeolites with intracrystal mesopores (i.e., 9 and 45 nm) or nano-sized ZSM-5 with a high external surface. All ZSM-5 zeolites were active in converting the initially produced via thermal pyrolysis alkoxy-phenols (i.e., of guaiacyl and syringyl/guaiacyl type for spruce and birch lignin, respectively) towards BTX (benzene, toluene, xylene) aromatics, alkyl-phenols and polycyclic aromatic hydrocarbons (PAHs, mainly naphthalenes), with the mesoporous ZSM-5 exhibiting higher dealkoxylation reactivity and being significantly more selective towards mono-aromatics compared to the conventional ZSM-5, for both spruce and birch lignin.

Performance of Heat Pump Water Heater (HPWH) Systems and Their Impacts on Electric Utility Loads

2010 ◽  
Vol 2 (2) ◽  
Author(s):  
Yahya I. Sharaf-Eldeen
Keyword(s):  
Heat Pump ◽  
Energy Savings ◽  
Electric Energy ◽  
Cost Savings ◽  
Electric Heating ◽  
Electric Utility ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Water Heaters ◽  
Peak Loads

This work involves measurements, analyses, and evaluation of performance of air-source heat pump water heaters (HPWHs), and their impacts on electric utility loads. Two add-on, heat pumps (HPs) rated at 7000 BTU/h (2.051 kW) and 12,000 BTU/h (3.517 kW) were utilized. The HPs were retrofitted to two 50 gal (189.3 l) electric water heaters (EWHs) with their electric heating elements removed. A third standard EWH was used for comparison. The testing setups were fully instrumented for measurements of all pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the surrounding air, volume of water drawn out of the storage tanks, as well as the electric energy consumptions of the systems. Performance measures evaluated included the coefficient of performance, the energy factor (EF), and the first hour rating (FHR). The HPWH systems gave EFs ranging from 1.8 to 2.5 and corresponding energy savings (and reductions in utility peak loads) ranging from 49.0% to 63.0%, approximately. The values obtained in the summer months were, as expected, somewhat higher than those obtained in the winter ones. The average values of the EFs and energy savings (and reductions in utility peak loads) were about 2.1 and 56.0%, respectively. FHR results were much lower for the HPWHs compared with those for the standard EWH. These results show that HPWHs are much more efficient compared with standard EWHs. While the average value of the EF for the EWH was about 0.92, the HPWHs yielded EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also show that HPWHs are effective at reducing utility peak loads, in addition to providing substantial cost savings to consumers.

Performance of Add-On Heat Pump Water Heater (HPWH) Systems and Their Impacts on Electric Utility Loads

2010 ◽  
Author(s):  
Yahya I. Sharaf-Eldeen ◽  
Craig V. Muccio ◽  
Eric Gay
Keyword(s):  
Heat Pump ◽  
Energy Savings ◽  
Electric Energy ◽  
Electric Heating ◽  
Electric Utility ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Energy Output ◽  
Water Heater ◽  
Heat Pump Water Heater

This work involves measurements, analyses, and evaluations of the performance of add-on, Heat Pump Water Heater (HPWH) systems in residential and small commercial applications. Two air-source Heat Pump (HP) systems rated at 7,000- and 12,000-BTU (2.051- and 3.517-kWh), were utilized in this work. The two HPs were retrofitted to two 50-gallon (189.3 liters) electric-resistance storage water-heaters with their electric heating elements removed. A third, standard electric water-heater (EWH), was used for comparison. The testing set-up was fully instrumented for measurements of pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the air in the surrounding space, volume of water draws out of the storage heater tanks, as well as electric energy consumptions of the systems. Several performance measures were used in this work, including the Coefficient of Performance (COP), which is a measure of the instantaneous energy output in comparison with the energy input; Energy Factor (EF), which is an average measure of the COP taken over extended periods of time; and the First Hour Rating (FHR), which is a measure of the maximum volume of hot water that a storage type water-heater can supply to a residence within an hour. The results obtained clearly indicate that, HPWH systems are much more efficient as compared to standard EWHs. While the average value of the EF for a standard EWH is close to 1.0, the HPWH systems yield EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also showed that, HPWH systems are effective at reducing utility peak demand-loads, in addition to providing substantial cost savings to consumers.

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