Search Results

You are looking at 1 - 10 of 95 items for

  • Keyword: sewage sludge x
Clear All Modify Search
Open access

Marta Wójcik, Feliks Stachowicz and Adam Masłoń

Abstract

Sewage sludge management in Poland is a relatively new field of waste management called “in statu nascendi”, the standards of which have not been recognized yet. It also requires the implementation of new solutions in the field of sewage sludge. So far, the most popular method of sewage sludge utilization has been landfill disposal. In line with the restriction placed on landfill waste with a calorific value above 6 MJ/kg introduced on 1 January 2016, agricultural use and thermal methods are particularly applied. Municipal sewage sludge may be successfully used in the cultivation of energetic plant plantations. The aforementioned waste could be treated as an alternative to traditional mineral fertilizers, which in turn might successfully provide valuable nutrients for plants. This paper illustrates the SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) associated with the use of sewage sludge from Świlcza-Kamyszyn WTTP (Podkarpackie Province, Poland) for agricultural purposes. This analysis could be useful in evaluating the utility of sewage sludge in perennial plant plantations in order to determine the appropriate waste management strategies.

Open access

Sebastian Werle

Estimation of reburning potential of syngas from sewage sludge gasification process

The motivation of this work was to define the reburning potential of sewage sludge gasification gas (syngas). Numerical simulation of co-combustion process of syngas in hard coal-fired boiler has been done. All the calculations were performed using the Chemkin program. Plug-Flow Reactor model was used. The calculations were modelled using GRI-Mech 2.11 mechanism. The highest NO conversions are obtained at the temperature of about 1000-1200 K. The highest reduction efficiency was achieved for the molar flow ratio of syngas equal to 15%. The combustion of hard coal with sewage sludge - derived syngas reduces NO emissions and the amount of coal needed to produce electricity and heat. Advanced reburning, which is a more complicated process gives efficiency of up to 80%. The calculations show that the analyzed syngas can yield better results.

Open access

Aneta Magdziarz, Małgorzata Wilk and Bogdan Kosturkiewicz

Investigation of sewage sludge preparation for combustion process

Waste disposal is imposed by the European Union under Treaty of Accession concerning waste management order. One of the waste disposal methods is thermal utilisation. The paper presents an investigation of sewage sludge briquettes used as a fuel in combustion process. The research study was carried out on samples taken from the Municipal Wastewater Treatment Plant in Bochnia. Briquettes with lime were formed. The analysis of the elementary chemical composition of municipal sewage sludge, the composition of the ash and thermogravimetric analysis were carried out. The results indicate that the prepared briquettes had sufficient fuel properties.

Open access

Radu Lacatusu, Anca-Rovena Lacatusu, Mihaela Lungu, Mihaela Monica Stanciu Burileanu and Andrei Vrînceanu

Abstract

The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1), i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, the content of Zn in the mud pond, but also from soil to which it has been placed, has become upper the normal content of the surrounding soil up to a depth of 260 cm. On the other hand, the vegetation installed on sewage sludge in the process of mineralization, composed predominantly of Phragmites, Rumex, Chenopodium, and Aster species had accumulated in roots, stems and leaves Zn quantities equivalent to 1463 mg Kg-1, 3988 mg Kg-1, 1463 mg Kg-1, respectively, 1120 mg∙Kg-1. The plants in question represents the natural means of phytoremediation, and sewage sludge as such may constitute a fertilizer material for soils in the area, on which Zn deficiency in maize has been recorded. In addition, the ash resulted from the incineration of plants loaded with zinc may constitute, in its turn, a good material for fertilizing of the soils that are deficient in zinc.

Open access

Franciszek Czyżyk and Agnieszka Rajmund

Abstract

This paper presents the results of studies which aim was to determine the pollution of the water environment for both methods of preparation for the utilization of sewage sludge in agriculture. The study was conducted in 2008-2012 in lysimeters filled with light sandy soil (clayey sand). During the study variants with equal doses of nitrogen in an amount of 20 g . m-2 (15.7 g per one lysimeter) were supplied to the soil in sewage sludge and in the compost made from the same sludge. These variants were used three times for two species of perennial plants: Miscanthus gigantenus i Sida hermaphrodita Rusby. In a variant of sludge soil fertilizing, it was leached into water environment more than 12% of the applied nitrogen over 5 years of research. In case of compost nitrogen leaching was reduced to 8.1-10.0% of the quantity supplied to the soil.

Open access

Adéla Čížková, Dagmar Juchelková and Helena Raclavská

The influence of hygienisation of sewage sludge on the process of pyrolysis

The aim of this work was to determine the influence of liming on the process of pyrolysis. Three samples of sludge from two wastewater treatment plants were selected for this study on pyrolysis: sludge without liming and limed sludge from the Central Wastewater Treatment Plant in Ostrava and sludge from the Wastewater Treatment Plant in Sviadnov. The samples had different content of calcite (CaCO3). The limed sludge contained 7% of CaCO3, sludge without liming 3.8% and sludge without liming from WWTP Sviadnov contained 0.5% of calcite. The results of laboratory pyrolysis proved that limed sludge released the maximum amount of carbon - 55.46 %, while sludge without liming from WWTP Sviadnov released only 48.92%. Calcite produces during its decomposition CaO and the product influences the pyrolysis process because it supports cracking of volatile organic compounds

Open access

Gabriel Borowski

Suitability Tests of Fly Ashes Vitrification from Sewage Sludge Incineration

The paper presents the results of preliminary studies on the properties of products made by vitrification of waste containing fly ashes from sewage sludge incineration. The performed tests of hazardous substances leached from the ashes, as well as the results of other laboratory tests confirmed the efficacy of vitrification. It has been found that the resulting products (sinters) could be used as a substitute aggregate for road foundations.

Open access

Aleksandra Sieciechowicz, Zofia Sadecka, Sylwia Myszograj and Monika Suchowska-Kisielewicz

Abstract

Sewage sludge is considered to be high quality fertilizer. Therefore, in Poland, it is used to fertilize energy plants. On the one hand, it allows using large amount of sewage sludge on the other hand it contributes to the production of renewable energy.

The study was based on monitoring the plantation of energetic willow Salix viminalis fertilized with sewage sludge from wastewater treatment plant in Sulechow. The aim of the investigation was to study changes of the lead content in different parts collected during a year and analyze the differences in the accumulation of lead in the plants planted at different times. The results of the study showed that the amount of lead content in the biomass willow was not influenced by sewage sludge used as a fertilizer.

Open access

Ewa Wiśniowska and Maria Włodarczyk-Makuła

Abstract

At present many WWTPs are focused on increasing quantity of biogas generated during sewage sludge processing. Various disintegration methods can be used for this purpose - thermal heating, ultrasonic disintegration, chemical treatment. The limiting step in sewage sludge digestion is hydrolysis, increasing the rate of this process allows for shortening solids retention time in digester, increasing soluble COD concentration in the reject water and as a result also biogas production. In technical scale ultrasonic and thermal disintegration are used. The most effective are ultrasounds below 100 Hz. In thermal conditioning various technological parameters are applied (from 60 - 80 °C to even 250°C, retention times from 15 min. to 2 hours). Effectiveness of the processes can be increased by using combined processes, e.g. thermal treatment and chemical stabilization. Chemical methods are at present mainly applied in laboratory scale. They include alkaline and acidic pretreatment or advanced chemical oxidation methods.

Open access

Anna-Maria Szöke

Abstract

In this paper it is presented the framing into polinary oxide systems in the case of optimal design of the oxide composition for obtaining raw ceramic materials. These calculations were carried out on two raw materials, which were the base of the experimental researches, for finding out the potential mineralogical composition. It was also followed, for the two raw materials, the framing options of the composition in oxide systems and the assessment of their belongings to possible subsystems.