Choice of a vacuum evaporation unit for increasing the concentration of humic gel

Humic drugs have a wide range of biological activity, affecting the metabolic processes in the body of animals and humans. Humins play a vital role in protecting the intestine from infections and favorably affect its functions, have the potential to suppress mold and bacterial growth, and reduce the level of toxins. When goats received humic substances they had higher milk yields, while significantly reducing total blood cholesterol. Sodium humate administered to broiler chickens increases the live weight by an average of 5–7 % and the livability of poultry by 3–5 %. The influence of humic acid on the quality of laying and egg quality in Japanese quails has been studied. The implementation of socio-economic and environmental programs of the agro-industrial complex provides for the improvement of technologies and technical means for the production of compound feed and protein-mineral vitamin additives for farm animals and poultry. The purpose of the research was to select a vacuum evaporation plant to increase the concentration of humic gel. It has been found that to increase the concentration of humic gel, it is advisable to use a vacuum evaporation plant with an ejector and a steam condenser. Methods for calculating the parameters of the ejector and the pressure reduction process in a vacuum evaporation unit have been developed. The dependences obtained to study the correlation between the area and the diameter of the nozzle water-air ejector, mass flow inject air, water pressure before the working nozzle, pressure inject air, density of the working water, pressure after the ejector, pressure of saturated steam, working temperature of water, temperature inject air, pressure reduction time.

The challenge to design a state of the art greenfield sugar refinery – an African experience

Numerous requirements are the challenge designing a state of the art sugar refinery. Local conditions have to be considered, starting from the landscape features, the size of the available plot of land and its infrastructure as well as the availability, quality and price of water and energy carriers. For most process steps, various technologies are available. It is necessary to make an ideal choice, one that harmonizes best with the location and the project parameters. Decisions such as whether to install a steam or gas turbine, the installation of a single or multi effect evaporation unit or the best juice purification concept have to be made as well as thoughts given to a possible sugar conditioning and the storage system, etc. This paper, with reference to a green-field refinery in Lagos Nigeria designed in detail by IPRO, describes the essential decision making steps concerning the definition of process technology and energy concept of the plant. The main technologies as well as the layout will be explained, considering future extensions. Qualified value added design and the application of modern tools are prerequisites for success and minimize the demand of time and cost for the construction phase quite considerably.

The Ice Selective Inlet: a novel technique for exclusive extraction of pristine ice crystals in mixed-phase clouds

Climate predictions are affected by high uncertainties partially due to an insufficient knowledge of aerosol–cloud interactions. One of the poorly understood processes is formation of mixed-phase clouds (MPCs) via heterogeneous ice nucleation. Field measurements of the atmospheric ice phase in MPCs are challenging due to the presence of much more numerous liquid droplets. The Ice Selective Inlet (ISI), presented in this paper, is a novel inlet designed to selectively sample pristine ice crystals in mixed-phase clouds and extract the ice residual particles contained within the crystals for physical and chemical characterization. Using a modular setup composed of a cyclone impactor, droplet evaporation unit and pumped counterflow virtual impactor (PCVI), the ISI segregates particles based on their inertia and phase, exclusively extracting small ice particles between 5 and 20 μm in diameter. The setup also includes optical particle spectrometers for analysis of the number size distribution and shape of the sampled hydrometeors. The novelty of the ISI is a droplet evaporation unit, which separates liquid droplets and ice crystals in the airborne state, thus avoiding physical impaction of the hydrometeors and limiting potential artefacts. The design and validation of the droplet evaporation unit is based on modelling studies of droplet evaporation rates and computational fluid dynamics simulations of gas and particle flows through the unit. Prior to deployment in the field, an inter-comparison of the optical particle size spectrometers and a characterization of the transmission efficiency of the PCVI was conducted in the laboratory. The ISI was subsequently deployed during the Cloud and Aerosol Characterization Experiment (CLACE) 2013 and 2014 – two extensive international field campaigns encompassing comprehensive measurements of cloud microphysics, as well as bulk aerosol, ice residual and ice nuclei properties. The campaigns provided an important opportunity for a proof of concept of the inlet design. In this work we present the setup of the ISI, including the modelling and laboratory characterization of its components, as well as field measurements demonstrating the ISI performance and validating the working principle of the inlet. Finally, measurements of biological aerosol during a Saharan dust event (SDE) are presented, showing a first indication of enrichment of bio-material in sub-2 μm ice residuals.