Michał Kopeć

The effect of low-temperature transformation of mixtures of sewage sludge and plant materials on content, leachability and toxicity of heavy metals

The aim of the study was to determine the influence of the process of low-temperature transformation and the addition of plant material to sewage sludge diversifying the content of mobile forms of heavy metals and their ecotoxicity. The experimental design included: sewage sludge+rape straw, sewage sludge+wheat straw, sewage sludge+sawdust, sewage sludge+bark and sewage sludge with no addition. The mixtures were subjected to thermal transformation in a chamber furnace, under conditions without air. The procedure consisted of two stages: the first stage (130°C for 40 min) focused on drying the material, whereas in the second stage (200°C for 30 min) proper thermal transformation of materials took place. Thermal transformation of the materials, caused an increase in total contents of heavy metals in comparison to the material before transformation. From among elements, the cadmium content changed the most in materials after thermal transformation. As a result of thermal transformation, the content of water soluble form of the heavy metals decreased significantly in all the prepared mixtures. Low toxicity of the extracts from materials for Vibrio fischeri and Lepidium sativum was found in the research, regardless of transformation process. L. sativum showed higher sensitivity to heavy metals occurring in the studied extracts from materials than V. fischeri, evidence of which are the positive significant correlations between the content of metals and the inhibition of root growth of L. sativum.

Assessment of respiration activity and ecotoxicity of composts containing biopolymers.

The research was conducted to determine if introducing biodegradable polymer materials to the composting process would affect selected biological properties of mature compost. Determination of biological properties of composts composed of testing their respiration activity and toxicity. Respiration activity was measured in material from the composting process by means of OxiTop Control measuring system. The ecotoxicity of composts was estimated by means of a set of biotests composed of three microbiotests using five test organisms. Introduction of polymer materials caused a decrease in respiration activity of mature compost. Similar dependencies as in the case of mass loss were registered. Compost to which a biodegradable polymer with the highest content of starch was added revealed the smallest difference in comparison with organic material composted without polymers. Lower content of starch in a polymer caused lower respiration activity of composts, whereas microorganism vaccine might have accelerated maturing of composts, thus contributing to the smallest respiration of compost. In composts containing biopolymers the following were observed: an increase in germination inhibition--2.5 times, roots growth inhibition--1.8 times, growth inhibition of Heterocypris incongruens--four times and luminescence inhibition of Vibrio fischeri--1.6 times in comparison with the control (compost K1). Composts containing biopolymers were classified as toxicity class III, whereas the compost without polymer addition as class II.

Content of PAHs, activities of γ-radionuclides and ecotoxicological assessment in biochars

Abstract The aim of this research was to determine the effect of thermal conversion temperature and plant material addition to sewage sludge on the PAHs content and the activity of selected γ-radionuclides in biochars, and to conduct an ecotoxicological assessment. The pyrolysis of the mixtures of sewage sludge and plant materials at 300°C and such temperature caused an increase in the contents of 2- and 3-ring hydrocarbons. During the pyrolysis of organic materials at 600°C, the amount of the following compounds was reduced in biochars: benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3c,d]pyrene, dibenzo[a,h]anthracene, and benzo[g,h,i]perylene. Among γ-radioisotopes of the elements, natural radiogenic isotopes were dominant. 137Cs was the only artificial radioactive isotope. The pyrolysis of the mixtures of municipal sewage sludge and plant materials revealed that isotope 40K had the highest radioactive activity. In the case of other analysed nuclides, activities of 212Pb, 214Pb, 214Bi, and 137Cs were determined after the sample pyrolysis. The extracts from the mixtures of sewage sludge and plant materials were non-toxic to Vibrio fischeri.

Factors Influencing Composting Poultry Waste

Organic recycling of waste, taking into account sanitary safety, should be a fundamental method for recovering the nutrients present in the waste for plants and organic matter. It also refers to by-products of animal origin, which are not intended for consumption by humans. In the present research , composting of hydrated poultry slaughterhouse waste with maize straw was carried out. A combination with fodder yeast and post-cellulose lime was also introduced, which modified chemical and physicochemical properties of the mixtures. The experiment was carried out by recording the biomass temperature for 110 days in 1.2×1.0×0.8 m reactors with perforated bottoms enabling active aeration. The following parameters were taken into consideration in the composted material: carbon, nitrogen, sulfur, respiratory activity, microorganisms, fractions of compost obtained after washing on sieves. Small amounts of fodder yeast favoured the development of microorganisms and caused a sanitary risk in the final product. At the initial stage, the temperature of raw compost in that object was several degrees lower than in the case of the composted mass without yeast addition. The addition of post-cellulose lime at ratios 6.5:1:6.5 (maize straw: poultry slaughterhouse waste: post-cellulose lime) caused a change in the time of microbiological activity, and led to its inhibition in the final process. In comparison to objects with poultry waste, the highest degree of hygienization was found in the compost with post-cellulose lime (with pH close to neutral). By adjusting the ratios of substrates we can influence the microbiological activity, but the amounts of individual substrates should be determined taking into account the quality of the obtained compost.

WYKORZYSTANIE ODPADÓW Z UBOJNI DROBIU DO PRODUKCJI KOMPOSTU

Poultry industry generates large amounts of waste, which in the biological treatment process creates a number of problems. One of them is a high amount of fat and creatine which is hard to decompose. Composting process was carried out with the waste from poultry farms and abattoirs mixed with maize straw, which was used to improve the structure and to increase the amount of carbon in the substrate. The chemical composition of composts from poultry waste involving maize straw meets the minimum requirements for organic fertilizers. It seems that recycling of organic waste from the poultry industry should be the primary method of nutrient recovery for plants and organic matter contained in them, however on condition that the health safety is preserved.

Effect of composting plant material with copolyester on quality of organic matter

Abstract The problem of incorporating plastics into the environment will be aggravating, both regarding its scale and kind of these materials. Investigations were carried out using aliphatic-aromatic copolyester poly (succinate-co-glutarate-co-adipate-co-terephthalate 1,4-butylene) with addition of fatty acid dimers. The work aimed to determine the effect of composting the copolyester with plant biomass on changes of fractional composition of humus substances and their stability. Copolyester was supplemented to the biomass in the form of a nonwoven fabric in two doses. It constituted 8 and 16% of the dry mass of the composted substrates. The composting process was run within two ranges of ambient temperature 25-30°C and 40-45°C. After the completion of this process, the degree of material maturing was assessed using manometric methods and the carbon content was analysed in the individual organic matter fractions. On the basis of cumulated respiratory activity AT4 a lack of composted material activity was revealed in the higher temperatures of the process. However, in the objects where copolyester was transformed in the lower temperatures this activity was considerably diversified. Adding copolyester to the composted biomass led to a diversification of the Cha : Cfa ratio. The values of Cha : Cfa ratio most approximating 1.5, ie the value regarded as optimal, were registered in the object, where copolyester supplement constituted 16% and the plant biomass was maintained within the 40-45°C temperature range.

YIELD FORMING EFFECT OF APPLICATION OF COMPOSTS CONTAINING POLYMER MATERIALS ENRICHED IN BIOCOMPONENTS

In a pot experiment the impact of composts containing polymeric materials modified with biocomponents on the diversity of crops of oats and mustard was examined. The composts used in the study were produced in the laboratory from wheat and rape straw, and pea seed cleaning waste with 8-percent addition of chopped biopolymer materials (films) which were prepared in the Central Mining Institute (GIG) in Kato wice. Three polymers differing in content of starch and density were selected for the composting. The pot experiment was conducted on three substrates: light and medium soil and on the sediment obtained after flotation of zinc and lead ores, coming from the landfill ZGH “Boleslaw” S.A. in Bukowno. The need for using such materials and substrates results from the conditions of processing some morphological fractions of municipal waste and from improving methods of reclamation. Yield enhancing effect of composts depends on the substrate on which the compost was used, cultivated plants and crop succession. Application of composts prepared with 8% of polymeric materials based on polyethylene, modified with starch as biocomponent, resulted in significantly lower yields in sandy (light) soil in case of oats and, in some cases, in medium soil. Subsequent plant yield did not differ significantly between the objects fertilized with compost.

The Influence of Biochar Enriched with Magnesium and Sulfur on the Amount of Perennial Ryegrass Biomass and Selected Chemical Properties and Biological of Sandy Soil

ABSTRACT Biochar used in this study was prepared from wheat straw and enriched with 10% solutions of chemically pure salts: ammonium sulfate [(NH4)2SO4] and magnesium sulfate (MgSO4 7H2O). The aim of this study was to determine the growth response of Perennial ryegrass L. as well as identify changes in chemical and biological properties of sandy soil after the application of biochar. A significant increase in the amount of Perennial ryegrass L. biomass was determined after amending the soil with unenriched biochar and biochar enriched with (NH4)2SO4. The highest immobilization of available forms of Mg was observed for biochar enriched with (NH4)2SO4. The highest dehydrogenase activity was determined in the soil with biochar enriched with MgSO4 7H2O.

Impact of thermal treatment of mixtures of sewage sludge and plant material on selected chemical properties and Vibrio fischeri response

Abstract The aim of the research was to evaluate the effect of temperature during the treatment process as well as the effect of adding plant materials to sewage sludge on selected chemical properties and Vibrio fischeri response. The mixtures were placed in a chamber furnace, under airless conditions. Two temperature procedures were applied: 300 and 600ºC; the exposure time in both cases was 15 minutes. Thermal treatment of sewage sludge without a plant component is not well-founded and may cause an increase in concentration of trace elements. Using the temperature of 300ºC caused significantly lower changes in the contents of total forms of trace elements than using the temperature of 600ºC. The metals extracted from the studied mixtures were not toxic for the Vibrio fischeri. In the case of the fractional composition of humic compounds, thermal treatment of mixtures of sewage sludge and plant materials is not beneficial in terms of labile fractions, but it had a beneficial effect on stabilizing the durable bonds between C compounds in those mixtures.

INFLUENCE OF CHARCOAL CALCINATION IN FIELD CONDITIONS ON HEAVY METAL CONTENT IN PLANTS AND IN THE IMMEDIATE VICINITY OF THE RETORTS

One of the ways of charcoal producing is its calcination in charcoal kilns called retorts in field conditions. In the charcoal production wood of deciduous trees is being subjected to the process of dry distillation. The process affects the surrounding environment. During the process a lot of pollutants are emitted to natural environment. One of them is ash, which contains heavy metals. The paper aimed at determining the effect of charcoal calcination on heavy metal content in the soil and plant material in the immediate vicinity. Charcoal calcination causes the alkalinization of the soil to 10 metres. In the closest vicinity, the calcination process increases Mn, Cd, Ni and Cu concentrations in the soil material. The influence of charcoal production on the con centrations Fe, Zn, Pb, Cr in soil material cannot be determined unanimously. The effect of the process on heavy metal content in plant material cannot be determined unanimously.