Forest can adjust climate and provide resources for the development of the society and tourism as well as promote the progress of human civilization, which is of great significance to the survival and development of human beings. With the industrial development and the improvement of people’s living standard, the development strength on forest resources is becoming higher than ever before. As forest resources are important resources which can maintain the ecological balance of the earth, its monitoring and protection is necessary. Hence, remote sensing technology has been developed for monitoring the changes of forest resources, which has the quickness characteristics and real-time spatial information acquisition and analysis capacities. This paper firstly introduced the geographical location, geomorphology, climate status, soil and vegetation types of Zhangjiakou City, Hebei Province and the basic theory of remote sensing monitoring such as vegetation spectral reflectance and normalized differential vegetation index (NDVI). Then, the NDVI was used to analyse the vegetation coverage and area ratio of Zhangjiakou City in 2006, 2010 and 2016. It was found that the vegetation coverage during the ten years from 2006 to 2016 showed an overall trend of growth. Conclusions: It is concluded that dynamic monitoring can effectively monitor and protect forest vegetation, which provided ideas for the follow-up forestry planning and ecological tourism development in Zhangjiakou.
Magnetic material may be added to proppant, as the magnetic marker allows to determine the range and efficiency of hydraulic fracturing. However, magnetic proppant may be also used in flowback fluid treatment and monitoring of environmental pollution. As a result of shale gas hydraulic fracturing, large volume of flowback fluid is created. Flow back fluid have similar properties to fracturing fluid, but it is potentially enriched with large amount of salts and organic compounds leached from shale. Magnetic proppant may serve as a heterogeneous catalyst during organic pollutants decomposition. Additionally, in case of leakage and consequently the fracturing fluid pollution, magnetic proppant is placed into the soil environment. It can be detected using magnetometric methods. This article discusses the above-mentioned issues based on the knowledge and experience of the authors and the literature review.
Natural flavonoids quercetin, morin, fisetin and luteolin were studied as potential photosensitizers for dye-sensitized solar cells (DSSC). Spectroscopic methods were used to investigate the formation of dye/TiO2 nanoparticles assemblies and the development of their absorption spectra. The results show that the flavonoids adsorb well on TiO2 nanoparticles and this process causes the shift of absorption spectra from the near UV into the visible range of solar light. The mode of binding of the dye molecules on TiO2 surface is analyzed by comparison of spectral absorption properties and with the use of structural differences introduced by fisetin and luteolin for discrimination between several possibilities.
A method for the reconstruction of the dynamics of processes with discrete time, developed in our previous papers, has been applied for study the dynamics of concentration of sulfur dioxide in lower troposphere. For the analysis, recordings of sulfur dioxide concentration from four measurement stations located in Poland (two of them has been located in huge cities and two in rarely inhabited regions) were used. We managed to obtain the deterministic and stochastic component of this dynamics. In result, we estimate the lifetime of sulfur dioxide in troposphere and the increase of sulfur dioxide concentration influenced by anthropogenic sources.
Combustion of fuels, including renewable fuels and thermal treatment of waste (CFCs, pesticides), is associated with emissions of pollutants including halogens. The reversible process of sorption/desorption of HCl, in a fluidized (bubbling) bed reactor (BFB), during co-combustion of Cl-materials, was carried out. The thermal decomposition of methylene chloride (DCM, CH2Cl2) in an inert sand bed with the addition of the hydroxyapatite sorbent (HAp, Ca5(PO4)3(OH)) was investigated. The process parameters were as follows: temperature - 930 °C, the air excess - 1.3, stream rate of CH2Cl2 - 50 cm3/h. The concentration of HCl, CCl4, CHCl3, CH2Cl2, CH3Cl, COCl2 in the exhaust gases were monitored online with FTIR spectroscopy. The main chlorine product was hydrogen chloride. Samples of unprocessed HAp, taken from the bed during the process, and solid apatite residues were analyzed by X-ray diffraction (XRD). The content of chlorapatite (Ca5(PO4)3Cl) in the analyzed samples was respectively 11, 53 and 19 %. X-ray fluorescence (XRF) analysis showed the molar ratio of Ca:P:Cl was: 1.00:0.36:0.01, 1.00:0.36:0.09, 1.00:0.37:0.04 respectively. The HAp could be used as an sorbent of the HCl(g) during combustion of materials containing chlorine.
Przemysław Drzewicz, Grzegorz Nałęcz-Jawecki, Agata Drobniewska, Anna Zgadzaj, Adam Smoliński, Marcel Krzan and Anita Starzycka
The oil containing drilling waste is a worldwide environmental problem associated with oil and gas exploration. In Poland, the problem of the drilling waste has become important since starting of shale gas exploration. The results of thermal treatment of drilling waste from shale gas exploration are presented. It has been shown that organic content vaporized completely at temperature up to 500 °C. The main problem is high content of chloride, sulfate, sodium, potassium, magnesium in the waste and its water leachate. Toxicity tests confirmed that high salinity of the samples pose important risk for environment. Due to the high content of barium, the drilling waste may be utilized in production of cement with high chemical and heat resistance and opaque to X-ray. Thermal treatment process is a viable option for remediation of the drilling waste; however, the product of the process needs further treatment in order to remove its high salinity.
Studies of the efficiency of Ni, Cu and Cd cations removal from water solutions were carried out, with the use of clay limestone, hen eggshells from eggs for consumption and hen eggshells after hatching, which main element is calcium carbonate. Hen eggshells are a waste product, which can be used as a substitute of clay limestone in removing heavy metals from wet flue gas desulphurisation installation. Mixed solutions of Ni, Cu and Cd were used in the research, with the composition similar to the waste water from wet flue gas desulphurisation installation: Ni (0.009-0.053 mmol/dm3), Cu (0.008-0.057 mmol/dm3) and Cd (0.003-0.008 mmol/dm3). The metals were determined by flame atomic absorption spectrophotometry (F-AAS). Kinetics of the process was analysed and equilibrium parameters were estimated, taking into consideration changes of the solutions pH during the process duration. It was demonstrated that the dominating mechanism of cations removal is their binding in hydroxides and carbonates. The studies demonstrated comparable characteristics of hen eggshells versus clay limestone, in the context of their application in removal of heavy metal cations from solutions.
Grażyna Sakson, Marek Zawilski and Agnieszka Brzezińska
Combined sewer systems in cities are increasingly equipped with additional storage facilities or other installations necessary for keeping the wastewater treatment plants from overloading during wet weather and reducing combined sewer overflows into receiving waters. Effective methods for reducing such negative phenomena include the temporary storage of wet weather flow in an end-of-pipe separate tank or in a sewer system. In this paper, four scenarios of wastewater storage for the Group Wastewater Treatment Plant (GWWTP) in Lodz (Poland) have been analysed: a storage in a separate single tank located in GWWTP, a storage in the bypass channel in GWWTP, in-sewer storage, and a combination of the aforementioned variants, also with real time control (RTC) system introduced. The basic calculations were performed using the EPA’s SWMM software for the period of 5 years (2004-2008). The chosen solution - storage in a separate storage tank - has been verified based on the inflow dataset from the years 2009-2013. The specific volume of the separate storage tank should be at least 22 m3 per hectare of impervious catchment area, but it could be reduced if additional in-sewer storage with RTC were introduced. Both options allow the effective protection of receiving waters against discharge of untreated sewage during wet weather.
One of the essential needs for retention reservoirs is to reduce the volume of wastewater flows in sewer systems. Their main advantage is the potential to increase retention in the system, which in turn improves hydraulic safety by reducing the risk of node flooding and the emergence of the phenomenon of “urban flooding”. The increasingly common use of retention reservoirs, the observed changes in the climate and the development of dedicated software tools necessitate the updating of the methods used to dimension retention reservoirs. So far, the best known procedures in this regard involve the application of analytical formulas and tools in the hydrodynamic modelling of current sewage systems. In each case the basis for the retention facility design is the evaluation of rainfall in terms of the probability of occurrence and duration that would result in a critical rainwater flow condition in the sewer system in order to define the required reservoir retention capacity. The purpose of this paper is to analyse of the feasibility of applying artificial neural networks in the preliminary estimation of the duration of critical rainfalls. Such an application of these networks is essential to the process of hydrodynamic modelling of the system and to determining the required retention capacity of the reservoir. The study used an artificial neural network model typically used as part of planning processes, as well as the Statistica software suite.
In this study, ANN (artificial neural network) model was applied to estimate the Ni(II) removal efficiency of peanut shell based on batch adsorption tests. The effects of initial pH, metal concentrations, temperature, contact time and sorbent dosage were determined. Also, COD (chemical oxygen demand) was measured to evaluate the possible adverse effects of the sorbent during the tests performed with varying temperature, pH and sorbent dosage. COD was found as 96.21 mg/dm3 at pH 2 and 54.72 mg/dm3 at pH 7. Also, a significant increase in COD value was observed with increasing dosage of the used sorbent. COD was found as 12.48 mg/dm3 after use of 0.05 g sorbent and as 282.78 mg/dm3 after use of 1 g sorbent. During isotherm studies, the highest regression coefficient (R2) value was obtained with Freundlich isotherm (R2 = 0.97) for initial concentration and with Temkin isotherm for sorbent dosage. High pseudo-second order kinetic model regression constants were observed (R2 = 0.95-0.99) during kinetic studies with varying pH values. In addition, Ni(II) ion adsorption on peanut shell was further defined with pseudo-second order kinetic model, since qe values in the second order kinetic equation were very close to the experimental values. The relation between the estimated results of the built ANN model and the experimental results were used to evaluate the success of ANN modeling. Consequently, experimental results of the study were found to be in good agreement with the estimated results of the model.