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Consideration has been given to problems of chemical activation of a solid product of hydrothermal carbonization (hydrochar) of biomass. Pellets from a mixture of poultry litter and straw subjected to carbonization in a fluidized bed in a medium of superheated water vapor at a temperature of 300°C were impregnated with water solution of ferric nitrate, dried in the air at a temperature of 100°C, and held for 2 h at a temperature of 300°C for degradation of iron(III) nitrate and its transformation into iron oxides. The pellets were activated at a temperature of 700–800°C in a horizontal tube furnace in an inert argon atmosphere. The obtained ferromagnetic sorbents have a rather developed system of micro- and mesopores. Furthermore, a twofold increase in the duration of activation results in an 18% increase of the pore specific surface, and the rise in the temperature of the activation process leads to an increase in this surface by 45%.

The analysis of experimental method for the evaluation of Umf in gas fluidized beds was carried out. It was based on pressure fluctuation measurements in which Umf is determined by the relationship between the standard deviation of pressure measurements and fluid velocity. Unlike previous works, this method was used to determine the minimum fluidization velocity of polydisperse beds of biomass (milled litter), and for beds of mixture of coal ash or sand particles and straw pellets. The experiments were carried out at room temperature in a transparent apparatus with a diameter of 172 mm. It was found that for some mixtures it is impossible to determine Umf from the curve of the pressure drop in the bed on fluid velocity. On the other hand, the method of determining Umf from the relationship between standard deviation of pressure measurements and fluid velocity allows this to be done for all studied beds.

A study has been made of the hydrodynamic characteristics of the transition of a multicomponent bed consisting of coal sludge and straw pellets to a fluidized state. It has been shown that increase in the fraction of large particles (pellets) in the bed leads to a decrease in its relative height and in the amplitude of pulsations of the pressure difference in it; this contributes to the rise in the degree of conversion of chemical reations occurring in the bed. The possibility of assessing the minimum fluidization velocity of a multicomponent bed from the dependence of the standard deviation of a pulsation of the pressure difference in it on the velocity of air blown though the bed has been proved.

Fluidization of two types of a bidisperse bed with marked bimodality of particle size distribution has been investigated experimentally. The possibility of using the mixture equivalent diameter is shown provided the latter is calculated by the weighted-mean diameter of the particles composing this mixture.

Poultry farms with floor-standing poultry generate large amounts of poultry litter waste. The direct application of this waste as an organic fertilizer does not ensure sustainable and cost-efficient utilization of all waste fractions, and can also be linked to environmental hazards. Therefore, the development of new technologies is required for processing poultry litter into a safe product with higher added value. In this work, the characteristics of activated carbon derived from hydrochar, along with the liquid products obtained from hydrothermal carbonization (HTC) and the wet torrefaction (WT) of poultry litter, were investigated. Poultry litter (PL) was applied in a mixture with sawdust (SD) in the following ratios: 1:0 (PL/SD 1:0), 1:1 (PL/SD 1:1), 1:2 (PL/SD 1:2), and 2:1 (PL/SD 2:1). WT processing took place in an innovative fluidized bed system in a superheated steam medium with low overpressure (less than 0.07 MPa) at 300 °C and 350 °C for 30–45 min. Conventional HTC processing was performed in a water medium at 220 °C for 1–4 h. The hydrochar produced in the experiments was activated with steam for 1 h at 450–750 °C. The porosity characteristics of activated hydrochar were measured, including pore size, pore volume, and specific surface area, in view of potential industrial applications as an adsorbent. Additionally, the contents of 5-hydroxymethylfurfural (HMF), as high-value product, were determined in the liquid products obtained from HTC processing, as well as in the condensate obtained after WT processing. Specific surface areas of the activated hydrochars may still be too low for application as adsorbent material. Hence, its use as a biofertilizer and soil improver should be preferred. Interestingly, the liquid fraction obtained from the innovative WT process displayed a significantly higher 5-HMF content compared to the conventional HTC process.

Oxidation catalysts, e.g., those for biomass combustion in a fluidized bed (olivine sand and catalyst ShchKZ-1), were compared. Samples consisting of straw powder, straw powder and uncalcined olivine sand, straw powder and calcined olivine sand, and straw powder and crushed catalyst ShchKZ-1 were prepared. The calcined olivine sand and catalyst ShchKZ-1 had practically the same influence on the sample mass loss and heat generation from the straw by heating.

An experimental study has been made of the distributions of the coefficient of external heat exchange over the volume of the fluidized bed with different forms of inlet gas distribution. It has been shown that the grid giving a concave inlet profile of the air velocity ensures a required homogeneity of the bed′s structure at a high level of heat exchange.

Results of determination of effective heat capacity of untreated biomass granules are furnished. It is shown that evaporation of moisture and other volatile components present in the material affects heat absorption by the material. A mathematical model of the temperature field in reactor chambers during low-temperature biomass pyrolysis is given.

The possibility of determining the regime of fluidization of a bicomponent bed by the dependences of the statistical characteristics of the pulsations of the different pressure in this bed on the velocity of the gas blown through it is demonstrated. An algorithm of estimating the characteristic gas velocities corresponding to the transformation of the bed into the regimes of fluidization and turbulent fluidization at room temperature and at much higher temperatures has been developed. This algorithm allows one to determine the indicated velocities more exactly, as compared to the traditional methods, by the dependence of the differential pressure in the bed on the velocity of the gas blown through it.

Torrefaction is considered as a kind of mild pyrolysis that is carried out under inert atmosphere (usually nitrogen) conditions. During this process, the moisture of the initial fuel and a portion of its volatiles are removed from the biomass particles towards the inert atmosphere. The resulted torrefied solid biomass has high energy density, durability and less hydrophilic character. The most beneficial result of torrefaction process is that biomass feedstock logistics cost can be reduced, as less tones of biomass are required for a given amount of energy input. The development of a process model examining basic parameters as reaction temperature and residence time can provide useful information, which can be used for the more efficient design of a torrefaction reactor. This study presents such a process model for a straw torrefaction pilot plant. This model is based on the thermodynamic calculation of a single and/or a two batch reactor, built on the commercial software ASPEN Plus. The calculation of required flow rates of inert gas, cooling medium for a specific biomass feedstock value, is based on relevant results found in literature.

A relationship is established between statistical characteristics of the random process of press-gradient pulsation in a fluidized bed and changes in the bed’s fractional composition. This relationship can be used to monitor the process of defluidization (transition of the bed from the fluidized to the non-fluidized state) based on the results of a comparative analysis of the above-mentioned statistical characteristics. The feasibility of performing such monitoring was confirmed experimentally from the combustion of lowmelting biogranules (straw granules) in a fluidized bed. It was found that the bed remains in the fluidized state as long as the dimensionless amplitude of the pressure-gradient pulsations does not exceed 0.1. The utility of the proposed monitoring method was also substantiated by comparative studies of changes in the fractional composition of a fluidized bed and the temperature and chemical composition of the flue gases.

The results of the research on fluidization of multi-solid materials in cold and hot models have been introduced. It turned out that the change graphs of the statistical characteristic of pressure fluctuation can be used for evaluate values of fluidization velocity. Index Terms—Multi-solid bed, Pressure fluctuation, Straw pellets combustion, Turbulent fluidization. I. I NTRODUCTION The technology of dedicated biomass combustion and coal and biomass co-combustion in a fluidized bed is increasingly applied aiming to achieve a better control over a combustion process with a simultaneous decrease in greenhouse gases, ash and sulfur oxides emissions into the atmosphere. Straw is one of the most easily available biomass resources and its energy utilization is also constantly expanding requiring longer transport distances of the material. This stimulates the production of straw pellets, with a bulk density of 650-750 kg/m³ over 100-150 kg/m³ of baled straw. Fuel combustion can be carried out in a co-fluidized or multi-solid fluidized bed of fine coal ash particles or straw ash and straw char particles loaded with straw pellets. A multi - solid fluidized bed is a circulating fluidized bed in which an entrained bed consisting of fine particles is transiting through a fluidized dense bed of coarse particles, i.e. a bubbling bed in the bottom of the riser (1)-(4). The value of the minimum fluidization velocity of particles forming the bed is required for the design of fluidized bed furnaces. However, as has been proven (5)-(14) it is not possible to apply the known method of a minimum fluidization velocity evaluation from the pressure drop through a bed versus gas flow rate curve for a confined, multi solid or binary particle mixtures fluidized bed. The purpose of the present study is to define a method for the experimental evaluation of the minimum fluidization velocity of a bed compounded of fine and coarse particles mixtures at room and elevated temperatures.

The results of the research on combustion of granular agricultural wastes (straw) in a fluidized bed formed by granules and solid products of their combustion are introduced. The proposed technology allows to prevent slag and ash agglomeration in a bed which usually obstructs the normal work of a boiler when we use known burning technologies (in a dense bed and fluidized bed of an inert material). The researches are carried out in accordance with the results of the analysis of statistical characteristic variations of pressure drop pulsations in a bed and it allows to diagnose slagging in a bed at an early stage of agglomerate formation.

This article presents test results for a reactor model designed for low-temperature pyrolysis of biomass. The efficiency of the pyrolysis attains maximum values at 240–250°C and a process duration of 50 min. The test results are used in the development of an industrial reactor with a capacity of 1 ton/h with respect to initial biomass.

Agricultural wastes (straw, sunflower or millet husk, etc.) are difficult to use as fuel because of low bulk density and relatively big ash content with a low melting point. It is possible to produce agropellets of agricultural wastes which are suggested to combust in a fluidized bed of pellets alone, their char particles and ash. The characteristics of the process of fluidization of agropellets are investigated at room temperature. The experiments on agropellet combustion in a fluidized bed are carried out in an experimental set-up. The results of the experiments have shown that in such a bed the pellets produced of straw and millet husk combust with the same rate as those of wood though the latter contain 8.76 – 19.4 times less ash. The duration of combustion of the same portion of straw pellets in a fluidized bed is 3.74 – 7.01 times less than the duration of combustion of cut straw in a fixed bed. Besides, the movement of agropellets prevents agglomeration and slagging of a boiler furnace.

1. A significantly higher uniformity of properties over the height of a lengthy component is achieved when it is quenched in a boiling layer with water injected onto its surface than after conventional quenching. In this case, the standard deviation of hardness and the warping of such a component are also appreciably lower. 2. The proposed method makes it possible to improve the quality of quenching, since no wetting of the boiling layer is required on the whole, the layer does not deteriorate in service, and no channels form in it. Use of liquid injected directly onto the component tends to reduce consumption of coolant, which is completely evaporated. The boiling layer remained dry on the whole, and its hydrodynamics is not disturbed. 3. The variation in the consumption of coolant over the height of the component and the subsequent reduction in aeration intensity make it possible to cool the component in precise conformity with its production thermograms; this improves the quality of the quench. Nonuniformity of component cooling with respect to its height is eliminated in this case.

In furnaces and other types of fluidized bed reactors one can easily observe gas bubbles flow and fluid jet preferable rise zones where solid particles in form of fountains are carried away from the layer. Let us call these layers as zones of local flowing. We assume that in these zones of local flowing occurs the removal of unburned fuel particles from fluidized bed. It results in heat leakage up to 20–40% due to mechanical imperfection of fuel combustion in types of vessels with fluidized bed furnaces. We investigated particles with diameter of 2,5–3,0 mm motion and local flowing zones formation in a model column of 172 mm in diameter at room temperature. Experimental application of air-separating grid enabled to form at the layer input “flat” and “convex” air velocity line. At the “flat” line the air distributed uniformly on the input section of the device. When the line was “convex” the air velocity at the layer input in the device center was twice higher than at the device periphery. It was found out that at “flat” line when air velocity increases there appeared zones of local flowing in the layer. To eliminate these zones one should increase the height of stationary particles layer. At “convex” line of input air velocity elimination of local flowing zones is possible by stable increase of air velocity or by lowering the height of stationary particles layer. It was concluded that for small fluidized bed fireboxes it is better to apply air-separating grids forming “convex” input air velocity line. The grid under discussion was manufactured to be applied in experimental fluidized bed firebox. There was carried out a detailed study of ordinary anthracite combustion in a firebox. It was established that at “convex” input air velocity line fuel loss due to entrainment amounted 2,0–2,5%. According to experimental results there were designed water boilers with heating efficiency from 300 up to 800 kilowatt. In these water boilers there was applied the grid forming “convex” input air velocity line. During tests there was burned culm (particle size from 0 up to 6 mm, heating efficiency of 20,6 MJ/ kg, output of volatile matter up to 6%, zoning 26,2–31,1%). Efficiency factor of these water boilers is 83–85% (without entrainment return to the firebox).Copyright © 2005 by ASME

During 50 days a group of 23 volunteers received lunches prepared on the basis of textured proteins of soy beans. Each lunch included 50 g of proteins. Laboratory investigation was carried on dynamic values of lipid metabolism, cell-mediated, humoral and local immunity. A total of more than 30 tests were made. The analysis of immunological reactivity in volunteers has revealed the immunomodulatory activity of soy bean protein similar to the reference modulator with known quantitative estimation of effects on cell mediated, humoral and local immunity. Statistic analysis of preliminary individual laboratory results and plotting of prognostic curves allowed to develop an original method of volunteer selection for whom soy bean diet may bring positive or negative results.

A study was made of the immunological mechanisms implicated in the evolution of diabetic microangiopathy. For this purpose in 270 patients with type I and II diabetes mellitus, the concentration of IgA, IgM and IgG was measured and compared with morphological alterations in skin biopsy specimens. The control group was made up of 30 normal persons (donors). The sections were stained with conventional methods, which made it possible to reveal by light microscopy the correlation between the intensity of diabetic microangiopathy and the rise of the IgG level.

Mixtures of isomeric 5-, 6-, and 7-carbethoxymethyl-1,2-dihydropyrrolizines were obtained by reaction of 1,2-dihydropyrrolizines with ethyl diazoacetate. The effect of the position of the alkyl groups in the two-membered ring on the ratio of isomers in the reaction products is demonstrated. A method for the isolation of 5-carbethoxymethyl-1,2-dihydropyrrolizines from the mixtures of isomers based on the difference in their reactivities in diazo coupling is described. The preferred conformations of the two-membered rings in the 5-carbethoxymethyl-1,2-dihydropyrrolizines are judged from the PMR spectral data.

According to our estimations, Russia can use up to 24 million tons of straw as fuel every year without harming either crop farming or agriculture. Straw as biofuel can be used for co-combustion with coal, including low-grade coal and coal waste (slurry). Taking into account the low bulk density of straw and granulometric composition of slurry (the particles are of size up to 0.2 mm) it makes sense to process this fuel into pellets, which are easy to transport and store. The feeding of pellets into a boiler furnace can be easily mechanized and automated. However, straw differs from wood and wood wastes by a high content of chlorine, silicon, phosphorus, and potassium. The presence of these compounds in straw contributes to the formation of slag agglomerates in the furnace, coherent deposits on the boiler heating surface and corrosion under these deposits. For the efficient combustion of biofuel with low-melting ash in boilers with furnaces with a small height the main combustion process should be carried out in the regime of a fixed, forced ventilated bed. Then, after a certain period of time, a bed must be transferred into a state of turbulent fluidization, and then returned to its original state. So the objective of the present work is to study the process of pellets combustion in such a bed (let's call it a pulsating bed).

The immunological effect caused by the influence of the local action of the ultrahigh frequency (UHF) electromagnetic field on the projection zone of the thyroid gland was studied. The action of UHF waves shown to be capable of producing both immunostimulating and immunosuppressing effects; their manifestation depended on the period of immunogenesis, affected by the action of UHF waves. The synthesis of nonspecific immunoglobulins showed greater resistance to the suppressive action of UHF waves than the synthesis of specific immunoglobulins, i.e. antibodies. The activation of the thyroid gland under the influence of UHF waves occurred before the immunostimulating effect was observed.

The immunological examination of 350 top level sportsmen has been made at different stages of training and competitions. This examination has revealed that the reaction of the immune system to superextreme loading can be divided into 4 phases: activation, compensation, decompensation and restoration. In the process of adaptation to increasing muscular loading, characteristic of modern competitive sport, the reserves of the immune system are mobilized, and the immunological characteristics are thus maintained at the initial level. In some of healthy adults the action of superextreme physical and psychoemotional loading produces the exhaustion of immunity reserves, which is manifested by the disappearance of certain classes of immunoglobulin from the blood and biological secretions 1-2 hours after the cessation of this action.

Live dysentery Sonne vaccine from a spontaneous mutant proved to be practically areactogenic and specifically harmless in oral immunization of children aged from 7 to 13 years, in doses of from 3 to 25 milliard live microbial cells and in single and triple immunization schemes. Weak reactions of the gastro-intestinal tract were noted with the same frequency (1.7%) in children immunized with the vaccine and in children given placebo (2.2%). There proved to be a significant increase in the serum of the immunized persons of the level of specific hemagglutinins, and also of the IgA-and IgM-titers in 82% of the persons vaccinated; they persisted at a high level for 2 months. The appearance of IgA-antibodies in high titres in the persons vaccinated orally pointed to a marked local and general immunological activity of the live dysentery Sonne vaccine from the spontaneous mutant processing the capacity to survive in the intestine of children for a long time.

The authors studied the immunoglobulin and specific antibodies content of various classes in the serum, coprofiltrates and the saliva of 68 patients suffering from Sonne dysentery and in 48 healthy adult persons. Mancini's test demonstrated a significant elevation of IgG and IgM content in the blood of dysentery patients in comparison with that in healthy persons, and the absence of any changes in the IgA content. The titres of specific IgG-, IgA- and IgM-antibodies in determination in the modified Coombs' test increased consideerably during dysentery infection and were found in high titres during the first week of the disease; they reached the maximum during the second week and persisted at this level for 3 weeks. The greatest antibody elevation was in the IgA-class. Antibodies revealed in the coprofiltrates and the saliva of dysentery patients belonged to IgA- and IgG-class. There proved to be a correlation of the antibody changes in these two secretions.

Considerable changes in the humoral factors of the general and local immunity were revealed during examination of 53 patients. A raised IgA and IgM level and a lowered titer of normal antibodies to antitoxins of diphtheria and tetanus and to staphylococcus antigen were revealed in the patients' blood. The content for IgG, lysozyme and normal antibodies to the antigens of dysentery and whooping cough was normal. A significant rise of the level of IgA, IgG, titers of normal antibodies and a decrease in the lysozyme activity were observed in the saliva.

A combined immunological study of cell-mediated and humoral immunity factors in sportsmen at the period of important competitions was made. The effect of the maximum bearable load was found to lead to the formation of a great number of universal rosette-forming lymphocytes and neutrophils. In the control group their number did not exceed 1-4% of the total population of these cells. Simultaneously, the suppression of the phagocytic activity of neutrophils and some of the humoral factors of systemic and local immunity with the parallel development of compensating processes were recorded.

The action of ultrahigh frequency (UHF) waves on the projection zone of the adrenal glands has been found to suppress both primary and secondary immune response, which is probably due to an increase in the glucocorticoid function of the adrenal cortex. The synthesis of nonspecific immunoglobulins has proved to be more resistant to the suppressive action of UHF than the synthesis of specific immunoglobulins.

Multiple oral immunization with pertussis corpuscular vaccine was shown to lead to the considerable stimulation of local and systemic humoral immunity. The data on the titers of specific and normal secretory antibodies, on the levels of IgA in washings from the oral cavity, the small intestine and the lungs, on the titers of agglutinins and hemagglutinins in the blood serum, as well as on the morpho-functional transformation of the mucous membrane and the associated lymphoid tissue in the digestive tract, are presented in their dynamics. Specific pertussis antibodies in high titers were detected in both intestinal and pulmonary washings. The multiple administration of the vaccine did not produce pathological changes in internal organs.

The authors studied the immunological shifts in the blood and saliva of 357 adults immunized with live enteral dysentery Sonne vaccine from a spontaneous mutant according to different schemes (1, 2, 3, 4 injections at 2--3-day intervals. The general level of IgA, IgG, and IgM increased during the immunization; there was also an elevation of the specific antibodies level of these classes in the blood of the persons vaccinated. Accretion was the greatest of IgA both in the blood and in saliva of the immunized persons; this pointed to a marked, chiefly local, immunological activity of the vaccine. As shown, during the immunization the rise and the changes in the antibody level of various immunoglobulin classes differed from such in dysentery infection; in the latter case, along with the IgA-antibodies there was a marked elevation of the IgG- and IgM-antibodies level. It is supposed that there was a possibility of a changed of a 4-time immunization scheme to-3-time one, with increase of intervals between the vaccine administration.

The authors determined the immunoglobulin and specific antibodies level in the blood serum of 17 children aged from 7 to 10 years during the immunization with live dysentery Some vaccine. Mancini's test demonstrated the absence of any differences in the amount of IgA and IgG in children of the given age group and in adults before the immunization; in comparison with adults, IgM was increased in children. 14 to 20 days after the immunization in children there was a significant elevation of the IgG only, whereas in adults the immunoglobulin level of all the 3 classes increased significantly. The titres of specific antibodies of the IgA-, IgG-classes and of hemagglutinins before the immunization detected by Coombs' test failed to differ in children from the titres of antibodies of these classes in adults; the level of IgM antibodies was much greater in children than in adults. The changes and accumulation of antibodies of various classes in children and adults during the enteral immunization with live dysentery vaccine differed significantly: in children the vaccine stimulated the IgA- and the IgM-antibody synthesis, whereas adults responded to the immunization by increased production of all the 3 antibody classes. On the basis of the noted immunological shifts a conclusions was drawn on a marked local immunization activity of the live enteral Sonne dysentery vaccine from the spontaneous mutant in children.