Maximum Allowable Emission Research Articles

Numerical Simulation of the Marine Environmental Capacity of Jinpu Bay

Based on the study of the marine environmental capacity, a water quality model and a response field-based linear programming method are adopted here. Water quality control objectives are taken as the constraint conditions, according to the requirements of Jinpu Bay’s functional zoning. The pollutant response coefficient and water quality background value are combined with the values of the water concentration quality control points set in each functional area and the target value of the functional area wherein they are located. The maximum allowable emission intensity of inorganic nitrogen, phosphate and chemical oxygen demand (COD) can be calculated using the linear programming method of the maximum allowable emission of pollutants at estuaries or sewage outfall points on Jinpu Bay. The research results reveal the diffusion of marine pollutants and the marine environmental capacity of Jinpu Bay. Some rivers need to reduce the discharge intensity and some other outlets still have a certain residual capacity. Based on this, the environmental capacity of Jinpu Bay was evaluated, and a technical reference is provided for the economic development of the region and the formulation of pollutant emission control policies.

Research on Optimization of Total Nitrogen Peak Suppression in Wastewater Treatment Based on the Data Driven Method

In order to solve the problems of water eutrophication, algae anoxic decay, and death by biological poisoning, which are caused by the excessive emission of total nitrogen in wastewater treatment process, this paper proposes a method of total nitrogen peak suppression which is based on neural network decision optimization. First, the SSORBF neural network is established according to the wastewater treatment process, and total nitrogen, inflow flow, current total nitrogen, dissolved oxygen concentration, and nitrate nitrogen concentration are selected to predict the total nitrogen concentration. Second, the density- and memory-based NSGA2 multiobjective optimization method is used to set the optimal solution to meet the requirement of energy consumption. If the prediction of total nitrogen exceeded the set value, the optimal control strategy is adopted to control the peak value of total nitrogen in advance, and it cannot exceed the national maximum allowable emission value. If the prediction of total nitrogen is lower than the set value, it continues to track the parameter set value. Finally, compared with other methods, the proposed method can effectively suppress the peak value of total nitrogen under 18 mg/L and reduce the energy consumption in wastewater treatment by 7.6%. It can provide decisions and advice for wastewater treatment plants.

Automated information processing systems in environmental monitoring

The article shows examples of using the algorithm for calculating emissions into the atmosphere during production activities in the process of laboratory tests for designing maximum allowable emissions and assessing the impact of possible activities on the environment. The calculation algorithm is based on the use of the ERA PC software package in the laboratory process, designed to calculate pollutants in all components of the environment. This software package allows you to make calculations for many parameters automatically, which simplifies the work of environmental designers. The use of this software package can be used in the training of specialists in the field of environmental monitoring.

Evaluation of alternative processes of methanol production from CO2: Design, optimization, control, techno-economic, and environmental analysis

Converting carbon dioxide (CO2) to methanol via direct hydrogenation has been regarded as an essential part of the pursuit of a decarbonized energy economy. This study first explored and evaluated alternative processes for converting CO2 to methanol, in which six schemes based on adiabatic and/or non-adiabatic fixed-bed reactors were focused. The research scope includes rigorous process design, optimization, techno-economic and environmental assessment, and control. The generated results indicate that the two-reactor system (Scheme 5), which employs a non-adiabatic one as the first stage and a adiabatic one follows, has the lowest production cost. This process reveals great potential for decarbonization (i.e. CO2-e = −1.314 Ton-CO2/Ton-MeOH), whereas less economic attractiveness (i.e. minimum required selling price (MRSP) of methanol = 998 USD/Ton, average market price = 378 USD/Ton). Correspondingly, the maximum allowable CO2 emission from utilizing hydrogen (MACEH2) was found to be 6.554 Ton-CO2/Ton-H2. This indicated that using hydrogen produced from steam methane reforming (SMR) with carbon capture on both syngas and flue gas (i.e. 5.7 Ton-CO2/Ton-H2) leads to net decarbonization. Furthermore, if the emission associated with the CO2 feed (specific energy = 2.8 GJ/Ton-CO2) is also considered, net decarbonation would be achieved by using hydrogen produced from biomass gasification (i.e. 3.1 Ton-CO2/Ton-H2). A more comprehensive comparison between various CO2 utilization processes, in terms of the decarbonization ability and economics, was performed. Through this, it is concluded that there has been no existing CO2-based process that is attractive in both aspects. Finally, a suitable control strategy was proposed for the selected scheme, which suitably handles the throughput and composition disturbances.

Degradation and phosphorus immobilization treatment of organophosphate esters hazardous waste by Fe-Mn bimetallic oxide

Organophosphate esters (OPEs) waste is difficult to dispose effectively because of its stability and the potential risk of P element. In this study, taking one typical organic extractant of tributyl phosphate (TBP) as an example, we proposed a strategy to treat OPEs inspired by chemical looping combustion (CLC) technology—oxygen carrier immobilization process (OCIP), aiming at efficient TBP degradation and simultaneous P immobilization. Adopting Fe-Mn bimetallic oxide (FMBO) as oxygen carrier, an almost 100% P immobilization efficiency was achieved under recommended conditions which were obtained by response surface methodology. Meanwhile, gaseous products released from TBP degradation, e.g., non-methane hydrocarbon, was lower than the maximum allowable emission concentration limit. Further characterizations implied that P-species released from reaction process were mainly immobilized as stable inorganic forms of metaphosphate, phosphate and pyrophosphate. On the basis of identifying degradation intermediates, we proposed a possible degradation pathways. FMBO as an oxygen carrier provided sufficient oxygen molecules for flameless combustion of OCIP process. Electron paramagnetic resonance measurement confirmed the existence of oxygen vacancies on FMBO surface, which contributed to the formation of •O2−. Oxidation by oxygen molecules and •O2− attack resulted in the degradation and mineralization of TBP, with simultaneously achieving P stabilization.

Efficient removal of trace uranium from nuclear effluents using irradiation-functionalized fibrous adsorbents with very high salt tolerance

The extraction of uranium from nuclear effluents is both conducive to the recycling of nuclear fuel and reduces environmental pollution. Adsorbents are widely regarded as the most promising materials for trace uranium extraction; however, the adsorption of trace uranium from high-salinity environments is a challenge for adsorbents used to recover uranium from nuclear effluents. In this study, four different irradiation-functionalized adsorbents were fabricated and evaluated to screen suitable adsorbents for the removal of trace uranium from nuclear effluents. We found that the adsorbent with synergistic adsorption groups (NWF-g-PGMA-AO) exhibited the most distinctive trace uranium removal efficiency and robust stability in acidic, alkaline, and high-salinity environments. It was the synergistic involvement of hydroxyls in the coordination of amidoximes with uranium that enhanced the binding energy of uranium to NWF-g-PGMA-AO, thus improving its performance. In addition, the residual uranium concentration decreased to the maximum allowable emission concentration of 50 ppb over a wide pH range, with a minimum concentration of 9.35 ppb. Interestingly, nitrate, sulfate, phosphate, and chloride anions in the effluents did not decrease the uranium removal efficiency, whereas fluoride considerably reduced the efficiency, and the removal ratio was negatively correlated with fluoride concentration. This is attributed to the formation of [UO2Fn]2−n (n = 1, 2, 3, 4) species, which exhibit a decreasing affinity for adsorbents with increasing fluorine atoms as revealed by density functional theory calculations. This work makes a stride in designing superior adsorbents with synergistic adsorption groups for extracting trace uranium from nuclear effluents.

Determining the Removal of Harmful Substances During the Construction Period

The construction industry is a fairly capacious consumer of various fuel and energy resources, the period of construction of buildings deserves special attention, which is comparable to the stage of operation in terms of average annual costs. A document containing maximum allowable emissions is mandatory for categories of enterprises, including construction industries, which, in the course of their work, pollute the atmosphere with emissions of various substances: combustion products, exhaust gases, dust, etc. The article assesses atmospheric air pollution with harmful substances from the operation of machines and mechanisms at the construction site during the construction of an apartment building. The values of harmful emissions by types of mechanization of construction works are considered. The maximum allowable total emissions into the atmosphere for the considered construction object were calculated in order to control the quality and composition of pollutants into the atmosphere from mechanized sources located at the construction site. The results of calculations of maximum allowable emissions make it possible to assess the level of impact on the atmospheric air. If the emission values are exceeded, monitoring of compliance with environmental pollution is introduced in order to take corrective measures to improve the environmental situation.

Optimization of Emission Reduction Target in the Beijing-Tianjin-Hebei Region: An Atmospheric Transfer Coefficient Matrix Perspective.

In recent years, the problem of atmospheric pollution has been concerning in the Beijing–Tianjin–Hebei region, due to the frequent haze. It has become a significant issue to improve regional air quality through appropriate emission reduction measures. In this study, considering the regional atmospheric transmission of air pollutants, the WRF/CALPUFF model (the Weather Research and Forecasting model coupled with the California Puff air quality model) was used to describe the impact of each city’s pollutant emissions on the concentrations of every city. Then, a new optimization model was designed to calculate the maximum allowable emissions of every city. The results showed that NOx and PM2.5 emissions need to be reduced by 44% and 48%, respectively, in the traditional mitigation scenario (any city’s pollutant emissions are not allowed to increase). However, in the optimized scenario, NOx and PM2.5 emissions should be reduced by 23% and 46%, respectively, to meet the national secondary standard. The emissions of cities with low transfer coefficients, such as Zhangjiakou, Qinhuangdao, and Chengde, could even be appropriately increased. This means that the optimized scenario could reduce the pressure on emission reduction. Although the optimization results are theoretical and idealistic, this research study provides a new idea for formulating emission mitigation policies in various regions to reduce the impact on the economy.

Evaluation of the effect of industrial enterprises on the atmosphere and efficiency evaluation of environmental protectionon the example of Prydniprovska thermal power plant

Heat and energy consumption is currently one of the largest environmental polluters. First of all, this is expressed in an increase in air pollution, poor quality of drinking water, soil pollution and the accumulation of certain types of waste. In order to reduce the harmful impact on the environment, it is necessary to solve the issues of effective purification and standardization of emissions and calculation of maximum allowable emissions. Therefore, the object of research is the impact of an industrial enterprise on the environment. One of the sources of environmental pollution is heat production enterprises, to which the Prydniprovska thermal power plant (Dnipro, Ukraine) belongs. The research is aimed at assessing the impact of the Prydniprovska thermal power plant (TPP) on the environment and develop proposals for the implementation of appropriate environmental measures. Like most industrial enterprises, Prydniprovska thermal power plant is a source of solid waste, polluted rains and gaseous emissions into the atmosphere. Since the enterprise is located within the city, the relevant environmental protection requirements for it have been increased. The economic activity of the enterprise is accompanied by the fulfillment of the requirements for the rational use of natural resources, environmental safety, planning measures for environmental protection and public health. In the work, an assessment was made of the impact of Prydniprovska thermal power plant on the environment and a description of the area where the enterprise was located was given.The analysis of these data allowsto give recommendations on the choice of the type of treatment facilities and the requirements for them. As a result of the research, it can be concluded that the excess of the surface concentration for the main emitted substances was not recorded. In the future, the study of emissions from the Prydniprovska TPP can be carried out on other emitted harmful substances, as well as after the work on the modernization of treatment equipment.

Economic dispatch of multi-area integrated electricity and natural gas systems considering emission and hourly spinning reserve constraints

With the increasing growth of gas-fired units and power-to-gas facilities, the power system and natural gas system become an integrated electricity and natural gas system (IENGS), which brings new opportunities to mitigate the associated environmental issues and deal with various uncertainties from electricity load, renewable energy generation, and gas load. Different geographical locations may have many IENGSs which are connected by electric or gas transmission lines, thus formulating multi-area IENGSs. These multi-area IENGSs are not simple addition of individual IENGSs, since renewable energy may distribute unequally between different IENGSs, and excess renewable energy needs to be transmitted from one area to another, but is limited by potential tie-line congestions. To solve these problems, this paper proposes an economic dispatch model for multi-area IENGSs considering tie-line congestion, maximum allowable emission bounds and hourly spinning reserve constraints. The considered multi-area IENGS consists of multiple single-area IENGSs, among which wind energy distribution varies considerably. The maximum allowable emission bounds of carbon dioxide and nitrogen oxygen are separately set based on their different influences on the environment. The hourly spinning reserves are allocated for both the power system and the natural gas system, which are provided by fossil fuel-fired units, power-to-gas facilities, gas pipelines, and natural gas storage facilities. After that, the presented model is converted into a mixed-integer linear programming problem for higher computing efficiency. Case studies for integrated systems are analyzed to demonstrate the effectiveness of the proposed model.

Technogenic impact of the heat and power plant on the environment and the development of environmental engineering measures

The article studies the waste generated during the operation of the heat and power plant, an energy facility. The analysis of atmospheric pollution by emissions of the Voronezh HPP-1, which uses coal as the main fuel, was carried out. A comparison is made with a thermal power plant using gas as a fuel source. The maximum allowable emission standards for pollutants generated during the use of coal were established and the excess of the MPC value by various types of emissions was shown: dioxide and nitric oxide; fuel oil and NO2+SO2 ash; sulfurous anhydride and carbon monoxide; soot and coal ash. The size of the Sanitary Protection Zone of HPP-1 was determined. Measures aimed at reducing the negative environmental impact of energy facilities such as combined heat and power plants are proposed.

Calculation of standards for permissible environmental impact for boilers with known technical characteristics

Emission of thermal power stations and boilers is regulated in accordance with the unified national regulatory requirements, taking into account the specifics of energy production, its life-sustaining function and is aimed at ensuring that air pollution is prevented as much as possible. The purpose of the regulation of emissions of thermal power plants is to limit its adverse impact on the air basin by developing, for the entire thermal power plant and each source of emissions on it, the maximum allowable emissions – control (in grams per second) and per annum (in tons per year), ensuring sanitary hygienic standards. Sanitary standards include the maximum permissible concentration, which reflects the level of components in the air that is safe for humans. In practice, several substances are simultaneously present in the air, the presence of which causes multicomponent air pollution. The atmospheric pollution index, which is calculated for a group of substances, is often used as a complex indicator of the degree of air pollution. Currently, mostly applied methods of component-wise assessment of atmospheric air quality are used in practice. When calculating atmospheric pollution by boiler houses, the total volumes of fuel combustion products are determined experimentally or by calculation. This article provides empirical formulas for calculating the above standards – the volume of flue gases, the maximum one-time emissions of ash, sulfur oxides, carbon and nitrogen for various boilers with known technical characteristics. Also, using the above formulas, a comparative analysis of the level of air pollution depending on the quality of various types of fuel burned in various types ofboilers.

Моделирование техногенного воздействия ТЭЦ на окружающую среду и разработка инженерно-технических природоохранных мероприятий

The waste generated during the operation of the thermal electric central, an energy facility, is considered. The analysis of atmospheric pollution by emissions of the Voronezh TPP-1, which uses coal as the main fuel, is carried out. A comparison is made with a thermal power plant using gas as a fuel source. The maximum allowable emission standards for pollutants generated during the use of coal are established and the excess of the MPC value by various types of emissions is shown: dioxide and nitric oxide; fuel oil and NO2 + SO2 ash; sulphurous anhydride and carbon monoxide; soot and coal ash. The size of the Sanitary Protection Zone of TPP-1 was determined. Measures aimed at reducing the negative environmental impact of such energy facilities as combined heat and power plants are proposed

Allocating Water Environmental Capacity to Meet Water Quality Control by Considering Both Point and Non-Point Source Pollution Using a Mathematical Model: Tidal River Network Case Study

Based on the principles of fairness and feasibility, a nonlinear optimization allocation method for pollutants was developed based on controlled section water quality standards, considering the synergetic influence of point and surface sources. The maximum allowable emission of pollutants from point and surface sources were taken as the objective function. The water quality attainment rate of controlled sections, the control requirements of pollution sources, and technical parameters of pollution control engineering were taken as constraints. A nonlinear optimization allocation model was established, and a genetic algorithm was used to solve the problem. As an example, the model was applied to a certain area in the Taihu Lake basin, southern Jiangsu province, China. The analysis results showed that the annual number of days for ammonia-nitrogen and total phosphorus meeting the standard were 334 and 332 days, respectively, under maximum allowable emissions for each pollutant, and the water quality compliance rates of the control section were 91.5% and 91%, respectively. The ammonia-nitrogen and total phosphorus concentrations in the controlled section achieved related water quality compliance rate targets of 90%. These all met the water quality compliance rate requirements of the control section. The results indicate that this method reflects the feasibility of optimizing the total allocation results systematically and intuitively, overcomes the insufficiency in the feasibility of the optimized allocation method, and provides effective and reliable technical support for control and management of the total pollutant amount based on water quality improvement.

UV-Assisted Cataluminescent Sensor for Carbon Monoxide Based on Oxygen-Functionalized g-C3N4 Nanomaterials.

Cataluminescence (CTL) is one of the most important sensing-transduction principles for the real-time monitoring of atmospheric pollutants. Highly sensitive CTL-based CO detection still remains a challenge because of the relatively poor reactivity of CO and the low catalytic efficiency of the catalysts. Herein, combining ultraviolet (UV)-light activation and chemical modification of the sensing element, we have successfully established a UV-assisted CTL sensor for gaseous CO based on g-C3N4 with high sensitivity, selectivity, and stability. UV irradiation can efficiently activate CO molecules and induce the generation of reactive oxygen species (ROS) for CO oxidation. Furthermore, carboxyl groups greatly facilitate the chemisorption of CO on functionalized g-C3N4 nanomaterials, thus enhancing the CTL sensitivity. The influences of experimental conditions and the possible catalytic mechanism of CO on functionalized g-C3N4 have been investigated in detail. Under the optimal experimental conditions, the proposed CTL sensor presents a detection limit (3σ) toward CO of 0.008 μg mL-1, which is much lower than the maximum allowable emission concentration of CO in atmospheric conditions (0.030 μg mL-1). The UV-CTL system is green, sensitive, stable, and low cost, and thus it possesses great potential application in gas sensing.

악취 배출구의 합리적인 배출규제를 위한 사례연구

In this study, field experiment, odor simulator, and dispersion modeling were used to evaluate the odor impact from J sewage sludge treatment facility. The height and flow rate of exhaust stack at this facility were 22.3 m and . The mean odor concentrations of the wet scrubber inlet and exhaust stack were and , respectively. The odor removal efficiency of wet scrubber showed 65%. The odor simulator is used for the regulated standard calculation of the exhaust pipe(stack). Resulting odor emission rate(OER) by odor simulator was . The forecasting result by Screen3 modeling showed that odor exhaust concentration up to was't exceeded maximum allowable emission level on site boundary().

Short-term economic emission power scheduling of hydrothermal systems using improved chaotic hybrid differential evolution

Increasing concerns over atmospheric pollution forces the power-producing utilities to retain their generations within maximum allowable emission levels. Therefore, in present-day power system operations, the minimization of emission pollutants along with the total fuel cost has become an important aspect in short-term generation scheduling of hydrothermal power systems. This paper presents an improved hybrid approach based on the application of chaos theory in a differential evolution (DE) algorithm for the solution of this biobjective constrained optimization problem. In this proposed methodology, self-adjusted parameter setting in DE is obtained by using chaotic sequences. Secondly, a chaotic hybridized local search mechanism is embedded in DE to avoid it from trapping at local optima and to enhance its search space exploring ability. Furthermore, new heuristic strategies are developed to effectively handle the complex hydraulic and thermal constraints. The feasibility and usefulness of the developed approach are demonstrated by its application on a standard hydrothermal test system compromising four multicascaded hydel plants and three thermal plants and the following three case studies are investigated: economic power scheduling, economic emission scheduling, and economic emission power scheduling. The simulation results illustrate the superiority of the proposed approach as compared to other recently established techniques.

Reliability-oriented multi-objective optimal decision-making approach for uncertainty-based watershed load reduction

Water quality management and load reduction are subject to inherent uncertainties in watershed systems and competing decision objectives. Therefore, optimal decision-making modeling in watershed load reduction is suffering due to the following challenges: (a) it is difficult to obtain absolutely “optimal” solutions, and (b) decision schemes may be vulnerable to failure. The probability that solutions are feasible under uncertainties is defined as reliability. A reliability-oriented multi-objective (ROMO) decision-making approach was proposed in this study for optimal decision making with stochastic parameters and multiple decision reliability objectives. Lake Dianchi, one of the three most eutrophic lakes in China, was examined as a case study for optimal watershed nutrient load reduction to restore lake water quality. This study aimed to maximize reliability levels from considerations of cost and load reductions. The Pareto solutions of the ROMO optimization model were generated with the multi-objective evolutionary algorithm, demonstrating schemes representing different biases towards reliability. The Pareto fronts of six maximum allowable emission (MAE) scenarios were obtained, which indicated that decisions may be unreliable under unpractical load reduction requirements. A decision scheme identification process was conducted using the back propagation neural network (BPNN) method to provide a shortcut for identifying schemes at specific reliability levels for decision makers. The model results indicated that the ROMO approach can offer decision makers great insights into reliability tradeoffs and can thus help them to avoid ineffective decisions.

An ARPS-CMAQ Modeling Approach for Assessing the Atmospheric Assimilative Capacity of the Beijing Metropolitan Region

A coupled ARPS–CMAQ modeling system was applied to investigate the atmospheric assimilative capacity (AAC) of PM10 in the Beijing metropolitan region of China. The AAC was defined as the maximum allowable pollutant emission that can be discharged to the atmosphere without violating the desired air quality objective in the planning region. The coupled modeling system was firstly evaluated through comparing the simulation results of PM10 concentration with the corresponding observations during four representative months in 2002, which showed an acceptable modeling performance. By using a trial-and-error approach, the validated modeling system was run through gradually reducing the emission strength within the modeling domain from a GIS-based pollutant emission database until a desired air quality objective was achieved. The air quality objective was characterized by the air quality guideline-satisfaction ratio (AQGSR) which was defined as the ratio of days when the daily PM10 concentrations are below the air quality standard during a certain time period. The PM10 emission within the modeling domain after such trial-and-error reduction under the condition of satisfying a certain AQGSR was considered its corresponding assimilative capacity. Accordingly, the atmospheric assimilative capacities of PM10 in the study region were identified corresponding to the AQGSR of 60, 65, 70, 75 and 80%, respectively. The relation between such capacity and guideline-satisfaction ratio was then established through regression analysis. The results could provide sound basis for decision makers in terms of effective air quality management by understanding the allowable pollutant discharge under different desired air quality objectives.

Air assimilative capacity-based environment friendly siting of new industries—A case study of Kochi region, India

Air pollution has become a matter of grave concern, particularly in mega-cities and urban areas, where the situation is alarming and becoming more and more severe day-by-day and warrants, therefore, careful planning to facilitate future industrial development. Site selection, with the objective of minimizing adverse environmental impacts based on environmental criteria is a vital prerequisite, particularly for air polluting industries. In order to locate any air polluting industry, the assimilative capacity of the region needs to be assessed carefully and planned accordingly, so that the receiving environment is not adversely affected. Assimilative capacity of a region/airshed, widely represented through the ventilation coefficient by many researchers in the past, does not give a clear picture about the amount of emission load that can be assimilated in a given region. The ventilation coefficient, at best, can only present a broad picture about the air pollution dispersion potential (low, medium or high) of the region. A modified approach, which utilizes air quality modelling as a tool to estimate the maximum allowable emission load that a region can assimilate without violating the stipulated standards, has been used for estimating the assimilative capacity of the air environment. Details of this approach have been presented in this paper through a case study carried out for the Kochi region, located in the Kerala State of India. A variety of emission and meteorological scenarios have been considered and critical emission loads have been estimated. This approach shall provide necessary technical guidance to the environmental regulatory authorities as well as to the industries in planning environment friendly industrial development.