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Table of Content

Volume 38 Issue 8
25 August 2022
Observation Indicators of Eco-city Construction Under the Perspective of Harmonious Co-existence Between Human and Nature
ZHAO Li-jun, LI Hai-dong, MA Wei-bo, WANG Nan, QIU Kuan-biao, ZHANG Long-jiang, LIU Chen-wei
2022, 38(8):  953-962.  doi:10.19741/j.issn.1673-4831.2022.0226
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The harmonious co-existence of man and nature is an important element of the construction of ecological civilization, and an important approach to solve the problems related to urbanization and urban ecological environment. Facing the demand of ecological security barrier protection and green and low-carbon transformation and development of cities and urban agglomerations, the author has sorted out the evolution of the connotation of eco-cities and the current situation of urban ecosystem observation, studied and constructed an observation index system for eco-city construction based on the harmonious coexistence of man and nature, including 28 indexes in four aspects:urban ecological security pattern, biodiversity protection, human living environment health, and green transformation and development. From the three dimensions of national policy guidance, local practice innovation and theoretical research and exploration, combined with the practice of eco-city construction in China, the study proposes a path to enhance the functions of eco-city, with a view to providing a theoretical basis and decision-making reference for the formulation of indicators and evaluation standards for national environmental protection model city construction in the new era.
Target and Modes of Ecological Restoration in Mining Areas
LI Hai-dong, HU Guo-chang, YAN Shou-guang
2022, 38(8):  963-971.  doi:10.19741/j.issn.1673-4831.2022.0196
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Ecological restoration and pollution control are effective measures to improve the eco-environmental quality, while the investment on ecological restoration and environmental governance plays a key factor. For a long time, ecological restoration in mining areas has been exhibited the phenomenon of ‘more passive responses and less active actions’, the reasons including lack of investment for eco-environmental governance, unclear targets of ecological restoration and the lack of regulatory standards all have led to the appearance of formalism in the ecological restoration of mining areas that violate the laws of nature in some regions. Focused on the needs of ecological civilization construction and regional sustainable development in the new era, we redefined the scope of the mining area from the perspective of ecological and environmental synergistic governance combined with long-term engineering practice and typical cases. It is pointed out that the scope of the mining area should include the areas of ecological damage and the areas with direct influence of environmental pollution, which is much larger than only the mine pit area. In this paper it is also put forward that the concept of mining complex should include natural resource subsystem, eco-environment subsystem and socio-economic subsystem. The differences and connections between land consolidation, vegetation recovery and ecological restoration are analyzed, and the definition and connotation of ecological restoration targets in mining areas are clarified based on the theory of synergistic governance and the concept of life community of Mountain-River-Forest-Farmland-Lake-Grass System. The targets of ecological restoration in mining areas include two responsible bodies including local government and mining enterprises for eco-environment governance, and three scales including mining complex, ecosystem and site. Finally, the patterns and characteristics of the ecological restoration in the mining area are proposed, including four categories:natural landscape similarity restoration mode, land reclamation and reuse mode, natural park construction mode and ecology-oriented development (EOD) mode. Among them, sustainable restoration modes include garden landscape, wetland park, green mine construction, geological relic protection, mine park construction, etc. Ecological security and the health of the human settlement environment in resource-based cities are the focal points in the construction of ecological civilization, this research gives the answers to the confusion in the scientific formulation of ecological restoration targets in mining areas, the synergistic governance of ecological restoration and environmental pollution, and the sustainable development of the region from the theoretical and practical levels, it is of great significance for classifying and promoting ‘ecological conservation and restoration based on natural solutions’, ‘integrated restoration of social-economic-natural complex ecosystems’ and ‘eco-environment supervision in mining areas’.
Urban Land-carbon Framework Construction Based on Ecological Network Analysis and Its Space-time Evolution Resea
ZOU Kang, SHU Yu-qing, LI Gui-e, YAN Qing-wu, BO Yan-su, ZHANG Si-yu, ZHANG Ding-xiang
2022, 38(8):  972-982.  doi:10.19741/j.issn.1673-4831.2022.0378
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For achieving the national "Dual Carbon" target, urban emission reduction is imminent. In this study, a spatial land-carbon framework was proposed. Taking the land use type migration in Xuzhou city from 2000-2010 and from 2010-2020 as example, The Ecological Network Analysis (ENA) was used to evaluate the positive and negative transfer of land-related carbon emissions and the changes of Ecological relationships. The land-carbon correlation rate was proposed to evaluate the comprehensive impact of land use changes on carbon balance in Xuzhou city. The interspecific ecological network between land use type conversion and carbon transfer was discussed based on the interspecific mechanism of ecology. The results show that:(1) the main positive carbon transfer was from cultivated land to industrial and transportation construction land, and the main negative carbon transfer was from industrial and transportation construction land to urban built up area. (2) In terms of time, carbon transfer intensity increased and the transfer type became more complex. In terms of space, the mutually beneficial relationship of land is distributed in subordinate districts and counties, while the competition relationship is distributed in central urban areas. (3) The contribution rate of carbon transfer thrust is mainly from farmland and the contribution rate of carbon transfer pull is mainly from industrial and transportation land. The land-carbon framework quantifies the land-related carbon transfer and obtains the ecological relationship between different land use types, which provides a new perspective for the spatial planning of carbon emissions.
Prediction of Peaking Carbon Dioxide Emissions in Main City Areas Based on LEAP Model and KAYA Model and Analyses on Its Uncertainty
DU Han-bei, ZHAO Li-jun, LIU Chen-wei, QIU Kuan-biao, LI Hai-dong
2022, 38(8):  983-991.  doi:10.19741/j.issn.1673-4831.2022.0205
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Carbon (CO2) emission is an important part of researches on urban carbon peak emission prediction. Accurate accounting of carbon emission is of great significance to achieve urban green transformation and development of urban industries and carbon neutrality. The industries in the main urban area are mainly based on living functions and Production R & D, and service industries, and there is a lack of independent statistical data such as energy consumption, which resulting in gaps in carbon emission verification. To this end, taking a municipal district in Nanjing City, Jiangsu Province as the research object, combined with the energy consumption statistics of Nanjing City from 2011 to 2020, this paper judges the carbon emission peaking situation in the municipal districts from the two aspects of "carbon emission influencing factors" and "terminal energy consumption calculation", The Kaya carbon emission identity and LEAP model were used to set different scenarios to predict the future carbon emission trend and peak time. The results show that:(1) From 2011 to 2020, energy consumption in the study area increased from 1 089 900 tons of standard coal to 2 220 200 tons of standard coal, and CO2 emissions were still in a period of rapid growth. Carbon emissions in 2020 increased by 82.27% compared with 2011. However, the energy consumption intensity gradually decreased from 0.324 to 0.200 tons of standard coal per 10 000 yuan; the proportion of the use of fossil fuels gradually decreased, while the electricity consumption increased. (2) The carbon emission intensity of the study area in 2020 is 0.337 t·10 000 yuan-1, which is lower than the average level of Nanjing (0.75 t·10 000 yuan-1). By actively promote low-carbon transformation development, the research area will be able to achieve the goal of carbon emmision peaking by 2030. (3) GDP per capita and energy intensity are the two most important factors affecting urban carbon emissions. The research results provide a feasible accounting method for the prediction of carbon emission peaking in the main urban area, which has guiding significance for urban carbon emission accounting, emission reduction model optimization and emission reduction task allocation.
Public Participation Willingness of “Internet + Tree Planting” and Dominant Mode Selection in Government and Enterprise under the Background of Carbon Neutrality
ZHANG Wen-rui, ZHANG Zhi-guang
2022, 38(8):  992-1001.  doi:10.19741/j.issn.1673-4831.2022.0291
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To further improve the public's enthusiasm for participating in afforestation in the context of carbon neutrality, based on the model of knowledge, attitude and practice (KAP) and the theory of planned behavior (TPB), this paper adopted questionnaire survey and structural equation model to empirically analyze the motivation and behavior choice of public participation in the existing mode of "Internet + Tree Planting" in China:the enterprise-led model represented by "Ant Forest" and the government-led model represented by "Internet + National Voluntary Tree Planting". The results are as follows:Environmental cognition and perceived behavioral efficacy significantly and positively affected the public participation attitude; Attitudes and perceived behavioral efficacy significantly and positively affected public participation intention; Perceived behavioral efficacy can directly or indirectly stimulate the public's participation willingness. Subjective norms have no significant influence on public participation attitude and willingness, that is, external environment can not effectively stimulate public participation behavior. Participation willingness plays a significant role in the public participation behavior under the two models, but the path coefficient of "Ant Forest" behavior was greater than that of "Internet + National Voluntary Tree Planting". Finally, "Internet + Tree Planting" should promote public participation by popularizing environmental knowledge, creating integrated platforms and opening interactive channels.
Calculation of Carbon Sink and Influencing Factors of Carbon Emission in the “Lucid Waters and Lush Mountains Are Invaluable Assets” Practice and Innovation Bases: The Case Study of Ninghai County
JI Rong-ting, HUANG Yan-qiu, CHENG Hu, CHEN Su-juan, ZHAO Zhi-qiang, CAI Jin-bang, LIU Chen-wei, LI Hai-dong, LI Rong-rong, ZHANG Long-jiang, ZENG Yuan
2022, 38(8):  1002-1009.  doi:10.19741/j.issn.1673-4831.2022.0096
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Scientifically evaluate the changing trend, temporal and spatial distributions and influencing factors of carbon (C) sinks in the "Lucid Waters and Lush Mountains are Invaluable Assets" practice and innovation bases plays an important role in guiding the construction of ecological civilization in the new era. Taking Ninghai County in Zhejiang Province as an example, this study measured C sinks and emissions in Ninghai County based on the IPCC C emission inventory, explored the spatial distribution of regional C sinks, and analyzed the influencing factors of C emissions in Ninghai County based on variance decomposition analysis. The results show that during the study period the C sink in Ninghai County showed a trend of increasing year by year, from 43.91×104 t in 2003 to 49.40×104 t in 2018, of which the forest C sink accounted for 88.21%-91.12%; the C source maintained stable during 2003 to 2006 and then increased sharply from 2007 to 2011, followed by a post-volatility decline and finally a stable trend, changing from 154.17×104 t in 2003 to 508.87×104 t in 2018. From the perspective of the spatial distribution of C sinks, the county-level C sinks in Ninghai County roughly showed a pattern of "west high and east low":"west > southeast > north > central"; C emissions in Ninghai County could be jointly explained by social factors, economic factors and "Lucid Waters and Lush Mountains are Invaluable Assets" construction driving factors, and the total explanation degree of these three factors was 60.86%, of which economic factors > "Lucid Waters and Lush Mountains are Invaluable Assets" construction driving factors > social factors. This research provides new ideas for the accounting of C sources and C sinks in the national "Lucid Waters and Lush Mountains are Invaluable Assets" practice and innovation bases, as well as provides a reference for the future policy formulation and green development for the county.
Study on Reduction of Reactive Gaseous Nitrogen of Compost Product by Microorganism and Chemical Additive in Composting Process of Livestock and Poultry Manure
GU Shen-yi, DAI Hai-yang, GUO Fan-jing, SHEN Wei-shou, LIN Xian-gui
2022, 38(8):  1010-1018.  doi:10.19741/j.issn.1673-4831.2021.0700
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Composting is one of the effective means to recycle livestock and poultry waste, but the loss of nitrogen during the process leads to a decrease in composting product quality. Moreover, ammonia (NH3) and nitrous oxide (N2O) emissions will aggravate air pollution and the greenhouse effect. To reduce the emission of reactive gaseous nitrogen during composting and improve the nitrogen content of composting products, pig manure and chicken manure were selected as raw materials for indoor simulated composting. The experimental treatments included inoculation with Bacillus strains, amendment with chemical additives, and combining Bacillus strains with chemical additives. The results show that the treatment with chemical additives only or a combination of Bacillusstrain with chemical additives significantly decreased the emission of reactive gaseous nitrogen and maintained nitrogen in composting product compared with dual non-inoculated and non-amended control. In the process of pig manure composting, the NH3 emission was decreased by 11% to 21% in treatment with chemical additives only, or dual treatment with Bacillus sp. H3-1 and chemical additives, and dual treatment of B. sp. H5-9 with chemical additives in comparison with the control. It was also observed that N2O emission decreased by 4%-6% in these treatments compared with the control. The content of NH4+-N in composting products increased by 6.7-7.7 times compared to the control. In the composting process of chicken manure, the N2O emission was decreased by 25%-26% in the treatment with chemical additives only or dual treatment with B. sp. H1-10 and chemical additives compared with dual non-inoculated and non-amended control. The NH4+-N content of composting products increased by magnitude of 3.3-3.9. Therefore, the amendment with chemical additives only or a combination of Bacillus strain with chemical additives could reduce NH3 and N2O emissions and maintain the nitrogen in composting products simultaneously. This study adds valuable information and provides a fundamental scientific knowledge towards the green and efficient resource utilization of livestock and poultry manure and help in achieving agricultural carbon neutrality.
Research on the Impact of Environmental Regulation and Risk Perception on Farmers' Environmental Friendly Behavior: Analysis Based on Intermediary Effect
ZHAO Jia-jia, LIU Ling-zhi, QI Jian-ling
2022, 38(8):  1019-1029.  doi:10.19741/j.issn.1673-4831.2021.0568
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Livestock and poultry farming manure is a major challenge in the control of rural environmental pollution, and the prevention and control of environmental pollution in the livestock and poultry industry is essential for the realization of rural revitalization and low-carbon recycling production. Based on survey data of 620 farmers in major meat duck production provinces, a Logit model was established to analyze the impact of environmental regulations and risk perceptions on farmers' environmentally friendly behaviors, and the mediation effect was adopted to analyze the impact of risk perception of environmental regulations on manure resource treatment behavior of farmers. The results show that environmental regulations and risk awareness both play positive roles in promoting famers' behaviors on treatment of manure. The imperative, incentive and guiding environmental regulations and the perception of risk reasons positively affects farmers' behaviors on treatment of manure. The perception of risk facts and risk causing losses are not significant, indicating that the farmers' behaviors are affected by the traditional concepts and the difference of policy-implementation among areas, and the farmers have a low awareness of manure resource utilization. Risk perception plays an mediating role in the impact of environmental regulations on famers' behaviors on treatment of manure. In order to improve farmers' awareness of environmental risks and promote environmental pollution prevention, relevant training and publicity should be carried out under the premise of effective implementation of the promotion policies, and the breeding subsidy incentive policy should be implemented based on local conditions. Therefore, the optimal allocation of environmental resources can be promoted, farmers can be encouraged to actively control pollution, and the farming benefits can be enhanced.
Evaluation of Rural Human Settlement Quality and its Key Driving Factors in Gansu Province
WANG Xiao-peng, HE Qi-ming
2022, 38(8):  1030-1040.  doi:10.19741/j.issn.1673-4831.2022.0243
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The construction of rural human settlements has become an important task in the implementation of rural revitalization strategy. The research on the internal mechanism and key driving forces can provide scientific basis for the governance and construction of rural human settlements. The measurement model of rural human settlements quality, canonical correlation analysis, and ridge regression model were used to realize the measurement of rural human settlements quality in Gansu Province. and the key driving factors were identified. The results show that:(1) The average value of rural human settlements quality in Gansu Province was 0.238, and the proportion of counties above the mean level was 45.98%. The living conditions, the industrial and economic development, and the governance of ecological environment in Gansu Province show a decreasing trend from northwest to southeast. The dimension of public service facilities is high in the middle and low at both ends. The low-level and lower-level evaluation units in infrastructure dimension are relatively scattered and widely distributed. (2) In the group of natural geographic variables, typical load of irrigated arable land was -0.798, and it has positive effect on the target variables such as infrastructure, living conditions and industrial economy. All the explanatory indicators in the regional economic development group showed positive correlation with the typical variables, and positively promoted the quality of human settlements. In the social control variable group, the canonical loadings of two explanatory variables, i.e. the proportion of residents with primary school education level-lower, and the proportion of minority villages, were -0.976 and -0.494, respectively, which negatively affected rural infrastructure construction and industrial economic development. (3) The ridge regression coefficient of the proportion of irrigated arable land was 0.143 (P<0.05), which is the key driving factor to improve the quality of rural human settlements, while the proportion of villages in mountainous and hill areas was -0.134 (P < 0.05) is the key constraint factor. The proportion of villages and towns near railway stations or expressway intersections (P<0.01) and labor force in non-agricultural industries (P<0.05) played positive driving role. In the social and cultural environment, the regression coefficient of the proportion index of residents below primary school education level was negative (P<0.01). The low education level of residents has become the key obstacle to the improvement of rural living environment quality.
Influence of Fractal Landform on the Distribution of Rural Residential Areas in the Upper Reaches of Minjiang River
XIANG Qing, HUANG Hong, YU Huan, KAN Ai-ke, HE Jie
2022, 38(8):  1041-1050.  doi:10.19741/j.issn.1673-4831.2021.0453
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Systematic study on the relationship between geomorphological environment and rural residential distribution in the upper reaches of Minjiang River is of great significance for understanding the characteristics and safety mode of human settlement ecological units in the eastern margin of Qinghai-Tibet Plateau. In this study, the fractal dimensions of the upper reaches of Minjiang River at different scales were calculated based on box counting method, and the quantitative relationship between fractal dimensions and rural residential areas was discussed by combining kernel density analysis and spatial clustering. Finally, based on geographic detectors, the influence characteristics and mechanism of watershed geomorphological factors on rural residential areas were revealed. The results show that:(1) On the overall scale, the juvenile development stage of fractal landform in the upper reaches of Minjiang River promotes the overall distribution form of rural residential areas and fractal landform to show positive correlation with leaf-like branching characteristics. On the scale of tributaries and small watersheds, the density distribution of rural residential areas, ethnic characteristics and watershed geomorphology development are consistent. (2) Gully density is the main factor affecting the distribution of rural residential areas, followed by elevation. At the same time, the gully density ∩ elevation has a significant two-factor enhancement effect. The effects of gully density, elevation and slope length on the distribution of rural residential areas have significant interval differences. (3) The production resources, natural disasters and landscape characteristics formed by the geomorphological development of the upper reaches of Minjiang River affect the site selection, migration, extinction and expansion of rural residential areas through coupling with the production, life and psychological needs of rural residential areas, and form the internal mechanism of the natural environment affecting the distribution of rural residential areas.
Study on Freshwater Ecosystem Service Flow in Watersheds of Southeastern Fujian under Water Pollution Stress
CHEN Zi-long, LIN Jing-yu, HUANG Jin-liang
2022, 38(8):  1051-1063.  doi:10.19741/j.issn.1673-4831.2021.0355
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Although freshwater ecosystem service flow regarding supply and demand has attracted wide attentions, few studies have considered the influence of water quality regulation service on fresh water provision service flow. The watersheds of southeastern Fujian are disturbed by human activities and typical water scarcity have been caused by pollution. Based on supply-demand analysis, InVEST model and scenario analysis were used to quantify ecosystem services supply, demand, and flows within Huashan Creek Watershed in Pinghe County, where freshwater ecosystem services are strongly affected by the intensive agricultural activities. The interactions of freshwater provision services (water quantity) and regulation services (water quality, taking nitrogen pollution as example) and their impacts on freshwater ecosystem services flow were addressed both at watershed scale (i.e., the natural status) and political scale (i.e., the proposed status). The results show that (1) In the context of watershed scale, the ecosystem services flows were 4.59×108 m3, and decreased to 9.9×107 m3 under nitrogen pollution stress with the reduction rate of 78.43%, while the paths of flow were not affected. (2) In the context of political scale (i.e., the proposed status), the dynamic flows of freshwater ecosystem services were about 4.63×107 m3, and decreased to 4.02×107 m3 considering water regulation services, with a reduction of 13.17%. Water quality have changed the supply and demand of ecosystem services, and subsequently altered the path of flows, which switched Xiazhai County from supplier to beneficiary. The results of the study could be references to the researches on ecosystem services flows and provide guidelines for regional/local water resources management.
Characteristics of Zooplankton Community Structure and Its Relationship with Environmental Factors in Hongjiannao Lake
BAI Hai-feng, SONG Jin-xi, LONG Yong-qing, LIU Gang, ZHANG Xing-lan, YUAN Yong-feng, LI Yin-di
2022, 38(8):  1064-1075.  doi:10.19741/j.issn.1673-4831.2021.0814
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For understanding the zooplankton community structure characteristics and the state of the water quality of the Hongjiannao Lake, and to scientifically protect the desert lake ecological health, an investigation of zooplankton community and water environment in Hongjiannao Lake were conducted from 2016 to 2017,and the seasonal variation trend and influencing factors of zooplankton abundance and diversity were analyzed. A total of 35 zooplankton species belonging to 30 genera were identified. The rotifera were dominant in the species composition, with accounting for 41.6%. The main dominant species were Vorticella microstoma, Notholca labis,Polyphemus pediculus,Moina mongolicaand Sinocalanus dorrii. The seasonal variation of number of species showed a trend of winter > spring > autumn > summer. The annual density of zooplankton ranged from 4.2 to 326.3 L-1 with an average of 61.9 L-1, and the annual biomass ranged from 0.001 to 1.138 mg·L-1 with an average of 0.193 mg·L-1. There was a seasonal difference in zooplankton abundance, showing the characteristics of summer > autumn > winter > spring. The mean value of Shannon-Weiner diversity index and Pielou evenness index were 2.040 and 0.712, respectively, indicating that the diversity in autumn and winter was higher than that in spring and summer. Canonical correspondence analysis show that water temperature, electrical conductivity and dissolved oxygen were the main environmental factors that significantly affected zooplankton community distribution. According to the biodiversity index and the comprehensive trophic level index, the results show that the water quality was moderately polluted and slightly eutrophicated in Hongjiannao Lake. The control of water quantity and the management of water quality had great influence on the zooplankton community structure. The results of this study can provide a reference for ecological protection and water resources development in Hongjiannao Lake.
Effect of Flow Disturbance Intensity on Nitrogen Release from Bottom Muddy of Plateau Rural Ditches
ZHENG Shu-jun, WANG Tie-yun, LIU Yun-gen, DU Peng-rui, WANG Yan, JIA Yu-jie, WEN Ming-fa
2022, 38(8):  1076-1083.  doi:10.19741/j.issn.1673-4831.2021.0460
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To investigate the effect of hydrodynamic disturbance on endogenous nitrogen (N) release in plateau mountainous rural ditches, N concentrations in overlying water under various flow disturbance intensities (0, 5, 15, 30, 60 L·h-1) were analyzed by a simulation experiment. The results show that:(1) Sediment N can be released into overlying water by the initial hydrodynamic disturbance and reaches the highest values of NH4+-N and TN at 5 and 60 L·h-1 flow disturbance intensity, respectively. After 30 days, N concentration in the undisturbed water was higher than that in the disturbed water; (2) Sediment TN contents increased with the increasing of disturbance intensity, which however were lower than the background values, showing 0 < 5 < 30 < 15 < 60 L·h-1; (3) The contents of different forms of transformable nitrogen (TTN) were in the order of strong oxidant extractable-N (SOEF-N) > strong alkali extractable-N (WAEF-N) > ion exchange-N (IEF-N) > weak acid extractable-N (SAEF-N), with releasing tendentiousness of IEF-N > WAEF-N > SAEF-N > SOEF-N. All N fractions of the sediment were at the lowest values under undisturbed treatment, indicating that the disturbance of flow benefits the N settlement in sediments, thus decreasing the risk of N to the surrounding environment.
Effect of Three Crystal Species on the Removal of Nitrogen and Phosphorus from Sludge Supernatant by Struvite Precipitation
LIN Hai-zhi, LI Ying-xue, REN Jing-wen, XU De-fu
2022, 38(8):  1084-1092.  doi:10.19741/j.issn.1673-4831.2021.0397
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Transforming nitrogen and phosphorus in sewage sludge from solid to dissolution is the key for the treatment or resource utilization of nitrogen and phosphorus. In this paper, the effects of pH value on the release of nitrogen and phosphorus from sewage sludge, and the effects of different crystal seeds (vermiculite, coconut-shell biochar and quartz sand) on the removal of nitrogen and phosphorus by struvite precipitation were studied. In addition, the effects of only crystal seeds and the co-treatment of crystal seeds and magnesium salts on removal efficiency of nitrogen and phosphorus in the supernatant of sewage sludge were also investigated. Results show that when the pH of the supernatant increased from 7.45 to 12, the concentration of phosphate (PO43--P) in the supernatant increased from 15.83 to 188.20 mg·L-1, and ammonia nitrogen (NH4+-N) increased from 48.97 to 166.46 mg·L-1. There is better removal efficiency of NH4+-N and PO43--P when n(Mg):n(P)=1.2, pH=10, followed by stirring and standing both for 30 min, then adding vermiculite, coconut shell biochar and quartz sand with 2, 2 and 0.5 g·(100 mL-1), respectively. Among the three crystal seeds, the removal efficiency of NH4+-N and PO43--P was higher by coconut shell biochar than those by vermiculite and quartz sand based on struvite precipitation induction. Compared to non-addition of crystal seed, when adding coconut shell biochar with 2 g·(100 mL-1), the removal rates of PO43--P and NH4+-N reached to 82.48% and 74.98% and increased by 9.14% and 13.38%, respectively. The results of X-ray diffraction and scanning electron microscopy (SEM) analysis show that the precipitates are mainly struvite which has high recovery value.