Assessment of the compost from the methane fermentation of litter from broiler production with a view to its utilization in organic plant production

The aim of the present research is to make an ecological assessment of the compost obtained from litter from broiler production /LBP/ according to the requirements of Ordinance №22/2001 for the MRL/Maximum Residue Level/ values of toxic elements and according to the Norms of the Canadian Ministry of Agriculture /2002/ with a view to its utilization in the organic production of plants. This research is necessary because, unlike broiler dung and domestic organic waste, LBP is heterogeneous in content and it includes different sources of cellulose / in Bulgaria hay is the most common as well as some part of the fodder/

Application of mathematical models to optimization of the methane fermentation of fowl dung

We applied mathematical modeling to the optimization of the methane fermentation of dung obtained from the breeding of farm animals in preceding research we carried out/Baykov, 1987, Baykov & Tyravska, 1991/. In the last few years compost is of greater interest as a resource for increasing soil fertility. The conducted research /Baykov, 1987/ indicates that the compost, obtained from the methane fermentation of fowl dung, is a source of biogenic chemical elements in optimal proportions. In the Ordinance for the organic production of plants /Ordinance №22/2001 of the Ministry of Agriculture and Forestry/ it is stated that the manure that can be used is produced from just a few farms. These are the reasons to carry out a research on optimizing the methane fermentation for a little farm, breeding 5000 laying hens without any litter, by applying mathematical modeling

Microbiological evaluation of sewage sludge in terms of possibilities of application in soil as a fertilizer

Research was conducted of sewage sludge from wastewater treatment plant for the existence of microorganisms of several major groups, containing pathogenic representatives with epizootological significance (Gram-negative aerobic bacteria, E. coli, Clostridium perfringens, the genera Pseudomonas, Staphylococcus, Enterococcus, fungi, and the total number of microorganisms), in order to assess the environmental safety of the final product. In parallel similar studies were made of fresh and composted cattle manures. A comparison of the results was made with the ready for manuring compost in order to assess the possibilities for the use of sludge for fertilizing. The quantities of microorganisms were given in CFU per 1 g of the investigated material, as well as per 1 g of dry substance for each of them. In our opinion this new approach to the reporting of the results per unit of dry matter of the investigated materials, allows for a more accurate comparison. It was found that the examined sewage sludge from wastewater treatment plant were rich in microorganisms from studied groups and their direct application in soils without prior treatment by aerobic or anaerobic digestion may represent epidemiological danger

Agroecologic valuation of organic waste in different technologies of storage

A study has been conducted, based on three types of fertilizers / cow, pig and bird manure/ and bioshlam /received from clearing station/ that have been storage in different technologies in order to make an agroecologic valuation. The different types of fertilizers and wastewater in different technologies of storage have been analyzed according to the following parameters: Dry matter (DM) ,Organic matter (OM), Organic Carbon (OC), Nitrogen Kjeldahl (N), Nitrogen Ammonium (N -ammonium), Nitrogen nitrate (N- nitrate), Sulfates (SO4) , Calcium Oxide (CaO), Magnesium Oxide (MgO), Patassium (K), P (Phosphorus), pH (H2O) and heavy metals – arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pd), Zinc (Zn). The received results show: variation of the percentage of dry material /from 92,12% to 4,03%/ according to the technology of storage. The way of storage has no essential influence on the content of carbon in the various stable fertilizers, where pig manure has the highest value of nitrogen in all technologies of storage. Near to the recommendable optimal values of C:N is stayed/dry/ and fresh/hard/ in all three fertilizer types. The technology of storage by the different manure types has no influence on the content of heavy metal. Exception can be observed as far as the zinc content in stale /fluid/ pig manure is concerned. High content of dry material can be observed in bioshlam received from clearing station. In both ways of production of variation in the content of dry material the ratio between the biogenic macro elements C:N remains. The free nitrogen forms (N-ammonium and Nnitrate) in bioshlam are higher to other organic waste in both technologies of storage. No values over the critically admissible in bioshlam are observed in both technologies of production

Ecological Assessment of differrent raw materials for biogas

ABSTRACT: A comparative ecologic valuation of different raw materials for biogas production has been made. The valuation is based on the qualities of the different substrates: from energy cultures (sugar, fodder and red beet, leaves mass from the Paulovnia spring and autumn leaves). Three type of fertilizer (cattle from non-litter breeding, swine and non-removable bird fertilizer litter) as well as substrates from waste water of the WTP- Waster water treatment plan (mixed sediment, primary and secondary sediment). The examined raw material has been analyzed according to the following parameters: Dry matter (DM), Organic matter (OM), Organic Carbon (OC), Nitrogen Kjeldahl (N), Nitrogen Ammonium (N - ammonium), Nitrogen nitrate ( N- nitrate), Patassium (K), P (Phosphorus), pH ( H2O) and heavy metals – arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pd), Zinc (Zn). The results of the examined substrates received from different raw materials (vegetal, organic fertilizers and waste water) give us ground to make the following conclusions: the examined substrates respond in the physical-chemical parameters to all technological requirements of raw material for biogas production (DM,C and proportion C:N). The established differences in the content of nitrogen / within the borders of 1,8% (substrate-leaves mass Paulovnia- spring) to 7,75% of substrate 7 (organic fertilizer)/ allow the combination of the substrates in order to adhere the Nitrate directive of the EU. The established differences in the active forms of nitrogen allow exploitation of programs for fertilizers with the participation of raw materials for biogas production. Our examination of substrates and show a content of heavy elements under the critical admissible limits. РЕЗЮМЕ: Направена е сравнителна екологична оценка на различни суровини за производство на биогаз. Оценката е на база качествата на различни субстрати: от енергийни култури (захарно, кръмно и червено цвекло, листна маса от Пауловния- пролетни и есенни листа, царевичен силаж и силаж Пауловния), три вида тор (говежда от безпостелно отглеждане, свинска и несменяема птича торова постеля), както и субстрати от отпадни води на ПС (първична,вторична и смесена утайка). Изследваните суровини бяха анализирани по следните показатели: Dry matter (DM) ,Organic matter (OM), Organic Carbon (OC), Nitrogen Kjeldahl (N), Nitrogen Ammonium (N -ammonium), Nitrogen nitrate (N- nitrate), Patassium (K), P (Phosphorus), pH ( H2O) and heavy metals – arsenic (As), Cadmium (Cd), Chromium ( Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pd), Zinc (Zn). Резултатите от изследваните субстрати получени от различни суровини ( растителни, органични торове и отпадни води) ни дават основание да направим следните заключения: Изследваните субстрати по физикохимични показатели отговарят на всички технологични изисквания на суровини за производство на биогаз (СВ, С и съотношение С:N). Установените различия в съдържанието на азот е границите на 1,8% (субсрат - листна маса Пауловния –пролет) до 7,75% (при субстрат 7 - органична тор) позволяват комбиниране на субстратите с оглед спазване на Нитратната директива на ЕС. Съществуващите различия в подвижните форми на азота дават възможност за разработване на програми за торете с участие на различни суровини за производство на биогаз. Проучените от нас субстрати показват съдържание на тежки елементи под критично допустимите граници

Movement of cadmium and lead in anthropogenically formed trophic chains of a pasture type

ABSTRACT: An investigation on the movement of Lead (Pb) and cadmium (Cd) in a trophic chain in 2 villages (industrial polluted and non polluted) has been conducted. The contents of the 2 heavy metals in the soil, food and in different organs of young kids, so as their transfer in the 3 trophic levels (using different static and dynamic methods of recalculation) have been established. The authors show, that it is expedient to determine quantitatively the chemical heterogeneity at the heterotrophic levels applying two criteria: along with the dynamic criterion “Clarc of concentration”(Cc), used up to know, to include also “Factor of bioaccumulation” (FB), which shows the real value of accumulation or dispersal of the chemical element according to its content in soil or at the trophic level of the autotrophic organisms. The increased Cc of lead /4,72/ and cadmium /49,14/ in soil is not the reason for the concentration in the nutrition chain at the level of the autotrophic organisms and at the level of the organisms phytophages /kids/. The studies of the FB show that the technogenically high Clarc of lead and cadmium in the ecotope is the reason for some changes in the metabolism, enabling the dispersal of lead along the trophic chain, the values falling down to 0,05 – 0,02 compared to its content in the ecotope, and, of cadmium – down to 0,03 – 0,15 in the tested organs and tissues. РЕЗЮМЕ: Проведено е изследване за движението на олово (Pb) и кадмий (Cd) в трофична верига в две села(промишлено замърсено и незамърсено). Установено е съдържанието на двата тежки метала в почвата, храната и различните органи на млади ярета и трансферът им в трите трофични нива, използвайки различни статични и динамични методи на изчисление. Авторите доказват, че е възможно количественото определяне на химичната хетерогенност на хетеротрофните нива, използвайки два критерия: наред с динамичния критерий “Кларк на концентрация” (Сс), използван досега, се включва и “Фактор на биоакумулация” (FB), който показва реалната стойност на натрупване или разсейване на химичния елемент според съдържанието му в почвата или на трофично ниво в автотрофния организъм. Повишеният Сс на олово /4,72/ и кадмий /49,14/ в почвата не е причина за концентрацията им в хранителната верига на нивото на автотрофните организми и на нивото на организмите-фитофаги /ярета/. Изследванията на FB показват, че техногенно високият кларк на олово и кадмий в екотопа е причина за някои промени в метаболизма, способстващи за разпръскване на оловото по трофичната верига и спада на стойностите до 0,05 – 0,02 в сравнение със съдържанието му в екотопа, и на кадмия – до 0,03 – 0,15 в изследваните органи и тъкани

Microbiological and epizootological characterization of materials from wastewater treatment plant

Studies were carried out for the presence of microorganisms of major groups, containing pathogenic agents with epizootological importance, in order characteristic of their dynamics at different levels in the treatment plant and assessing the environmental safety of the final materials. For this purpose were traced the changes in the quantities of microorganisms contained in the materials from successive levels of processing. It was found that the purified water inlet and outlet does not contain Salmonella enterica. Presence of Escherichia coli and Clostridium perfringens beyond the requirements of the regulation (Decree N339, 2004) was not established, as well as Enterococcus spp. The tested sludge contained microorganisms from these groups and could not be deposited in the soil without prior aerobic or anaerobic processing. The draining in the nature of treated water at the outlet of plant does not hide environmental risk. In addition to monitoring of the sanitary indicative bacteria, the following of the main groups of Gram-negative and Gram-positive microorganisms in the water and sewage sludge allows more reliable assessment of their decontamination. Furthermore, the new approach for reporting the results in a unit of dry matter of the studied materials, proposed here, allows their more exact comparison

Co-digestion of waste activated sludge and silaged mix of chicken litter and fodder beet

In order to determine the yield of methane in a Co-degradation study with different substrates. The study involved the following substrates : WAS only; WAS+silage 2:1; WAS+silage 1:1; WAS+silage 1:2. Studieed is the contents of the macro and micronutrient in the tested substrates and biogas yield after methane fermentation. It was found that major disadvantage of the BMP test is the fact that it does not provide short-term results because of it s duration, methane yield during a shorter period could be predicted by evaluating the reaction rate provided by the rate constant

A new concept for the bioaccumulation of lead and cadmium along a food chain with farm animals

The term bioaccumulation defines the selective accumulation of toxic substances/chemical elements and compounds/ along the food chain. During the period after the 60’s the bioaccumulation of some pesticides was researched. Hebel & Wrigt /1996/ indicate that if the content of DDT in lakes is 1 unit then it reaches 10 million units in predatory fish. This phenomenon, for some unknown reasons, is mechanically transferred to the accumulation of toxic chemical elements. In scientific literature it is admitted that the degree of bioaccumulation of toxic chemical elements is comparable with that of xenobiotics. In this research we set our aim to study the degree of bioaccumulation of lead and cadmium and to formulate a concept for the bioaccumulation of these elements, which have an increased technogenic klarck in many regions of Bulgaria. The reason we carried out the research in this direction is our first study/together with Krynski/, which indicated that in ecotopes with increased klarck of lead and cadmium, the content of the two toxic elements is higher in liver and kidneys of rabbits, but the degree of bioaccumulation is considerably lower in comparison with pesticides

Reduction of sanitary indicator microorganisms in anaerobic digestion of poultry litter in combination with silages

ABSTRACT: In connection with experiments aimed at optimizing anaerobic digestion of organic fertilizers, microbiological tests were performed to assess the epizootiological safety of resulting finished product to fertilize the soil by quantities of sanitary indicator microorganisms. Mixtures of substrates were composed and tested in technological parameters established for other experiments: mesophilic temperature regime 33oC, dry matter content of 7%, residence time in the digester 15 days. The substrates tested were beetroot, sugar and salad beets, corn silage and leaves of Paulownia elongata, and silage combinations of these feeds in ratio 60:40 with mulch litter from broiler chickens. It was found that significant reduction of microorganisms was realized in the final products, which were assessed as safe for soil application. The ensiling of poultry litter in combinations of these feeds had the effect of reducing the amount of microorganisms in almost all examined groups therein. The most significant was the reduction in the quantity of sanitary revealing bacteria in the manure after its ensilage with autumn leaves of P. elongata and beetroot, and the least - with the participation of sugar beet. Microbial reduction was to the greatest extent in bioslime produced by anaerobic digestion of poultry litter ensiled with corn. Of the silages from different types of beets with poultry manure, during anaerobic digestion highest decontamination was achieved in this with sugar beets. After anaerobic degradation of the studied feed without poultry litter, at least microorganisms were found in bioslimes from the three types of beet, as well from the silage from P. elongata. РЕЗЮМЕ: Във връзка с експерименти, насочени към оптимизиране на анаеробното разграждане на органични торове, са извършени микробиологични изследвания за преценка на епизоотологичната безопасност на получените крайни продукти за наторяване на почви според количествата на санитарно индикаторните микроорганизми. Съставени са смеси от субстрати при установени при други експерименти технологични параметри: мезофилен температурен режим 33оС, съдържание на сухо вещество 7%, време на престой в биореактора 15 денонощия. Изпитани са захарно, кръмно и салатно цвекло, царевичен силаж и листа от Paulownia elongata, както и силажи от комбинации на тези фуражи в съотношение 60:40 с торова постеля от пилета-бройлери. Установено е, че се осъществява значително редуциране на микроорганизмите в крайните продукти, които се преценяват като безопасни за внасяне в почвите. В най-голяма степен микробната редукция е при биошлама, получен при анаеробното разграждане на комбинацията от торова постеля с царевичен силаж. От трите вида цвекло, силажирани с птичи тор, при анаеробно разграждане се постига най-висока деконтаминация с участие на захарното цвекло. При анаеробно разграждане на изследваните фуражи без птичи тор най-малко микроорганизми се установяват в биошламовете от трите вида цвекло, както и в силажа от P. elongata