Development of a Novel Gasoline Particulate Filter Loading Method Using a Burner Bench

In view of the deliberations on new Euro 7 emission standards to be introduced by 2025, original equipment manufacturers (OEMs) are already hard at work to further minimise the pollutant emissions of their vehicles. A particular challenge in this context will be compliance with new particulate number (PN) limits. It is expected that these will be tightened significantly, especially by including particulates down to 10 nm. This will lead to a substantially increased effort in the calibration of gasoline particulate filter (GPF) control systems. Therefore, it is of great interest to implement advanced methods that enable shortened and at the same time more accurate GPF calibration techniques. In this context, this study presents an innovative GPF calibration procedure that can enable a uniquely efficient development process. In doing so, some calibration work packages involving GPF soot loading and regeneration are transferred to a modern burner test bench. This approach can minimise the costly and time-consuming use of engine test benches for GPF calibration tasks. Accurate characterisation of the particulate emissions produced after a cold start by the target engine in terms of size distribution, morphology, and the following exhaust gas backpressure and burn-off rates of the soot inside the GPF provides the basis for a precise reproduction and validation process on the burner test bench. The burner test bench presented enables the generation of particulates with a geometric mean diameter (GMD) of 35 nm, exactly as they were measured in the exhaust gas of the engine. The elemental composition of the burner particulates also shows strong similarities to the particulates produced by the gasoline engine, which is further confirmed by matching burn-off rates. Furthermore, the exhaust backpressure behaviour can accurately be reproduced over the entire loading range of the GPF. By shifting GPF-related calibration tasks to the burner test bench, total filter loading times can be reduced by up to 93%.

Results of the evaluation of the semi-empirical model on the selection of optimal constructive and technological parameters for a granulated loading filter

Topicality. A survey of the water use system at a state-owned enterprise processing agricultural products revealed the technological processes that cause biofouling of pipelines by colloidal inclusions (mainly phytoplankton conglomerates of blue-green algae). The implementation of measures that can protect existing technological structures against the ingress of significant masses of phytoplankton is an urgent task that can be solved with the help of mechanical filters. The efficiency of previous granulated loading filters depends very much on the properties of the filter loading. When filter loading is made of foamed polystyrene granules of food brands, phytoplankton retention is quite effective due to the physical adsorption of cyanobacteria conglomerates on the surface of these granules. Research results. By applying the semi-empirical model developed in IWPLR of NAAS, the optimal design and technological parameters of the filter with foam polystyrene loading were selected. That enabled to develop the design of a clarifying filter - a phytoplankton retainer for the treatment of circulating water at the enterprise Chervonoslobidsky distillery. In the lower part of the filter the lower drainage system in the form of a false bottom is placed, equipped with hole caps. It provides the source water entry for filtration and discharge of flush water during filter washing. The granules of the filter loading are kept from floating with the false bottom of the upper drainage, which is equipped with return filters - hole caps. Filtered water is collected in the abovefiltering space between the false bottom and the upper part of the filter body, from where it is delivered through a pipeline to the consumers. The application of the developed filter design allows reducing the construction costs and simplifies the filter design, which in turn increases its reliability and overall service life. The practical application of this filter provided the required degree of retention of cyanobacteria cells and conglomerates from the treated water. This filter design differs from the standard with a 1.5 times increased filter loading layer. This enabled to double the duration of a filter cycle and, at the same time, did not increase the volume of flushing water, i.e. operating costs. Conclusions. Based on the results of the developed semi-empirical model, the design and technological parameters of granular filters for recycling of wastewater from the distilleries were determined, which became the basis for developing a new filter design for water purification from cyanobacteria cells and colonies. The high efficiency of the developed design of the clarifying filter - phytoplankton retainer was experimentally proved. The use of the developed filter increases the economic efficiency of the circulating use of the wastewater from Chervonoslobidsky distillery by 1.3 - 1.5 times compared to the market offers of mechanical filters.

Not so fast with the filter! Is it really in the inferior vena cava?

Inferior vena cava (IVC) filter placement can lead to rare but sometimes serious complications, including malposition of the IVC filter in a non-target vessel or organ. We present the case of a 74-year-old male who presented to our institution for a percutaneous nephrostomy tube change and was incidentally found to have two IVC filters, one of which was properly positioned in the IVC and one of which was improperly deployed in the right ascending lumbar vein. Venography through the sheath before filter loading and deployment decreases the risk of malpositioning the IVC filter.

Mathematical modeling of the process of ferrum removal in a biological reactor by bacteria Gallionella and Leptothrix

This paper proposes a mathematical model for computer prediction of the process of biological deironing of groundwater in a bioreactor, taking into account the presence of two types of iron bacteria Leptothrix and Gallionella in groundwater while maintaining a constant filtration rate. An algorithm for a numerical-analytical method for solving the corresponding nonlinear boundary value problem for an inhomogeneous system of differential equations in partial derivatives of the first order has been developed. The developed model allows to use computer experiments to predict the change in time on the depth of contact loading of cleaning efficiency, distribution of bacterial biomass values ​​in both filtered water and in filter loading, mass of stationary and mobile matrix structures. Also, the proposed model allows to predict the duration of effective operation of the biological reactor of iron deironing between its washing.

Kinetics of extraction from water solutions of Fe3+, Cu2+ and Pb2+ + ions by filter loading, obtained by blinding plasters

In this study, we investigated the kinetics of extraction from aqueous solutions of Fe3+, Cu2+ and Pb2+ by filter loadings, derived from the steelmaking slags. A formal kinetic approach based on the relationship between the relative deposition rate (α) and time (τ) was used to estimate the mechanism and kinetic parameters of the deposition process). From the set of equations are selected those that in a given region of the degree of completion of the process gave the minimum value of the variance, that is, described the process in the system at this stage with the maximum probability. Three models that best correspond to real processes are selected. It was found that the deposition process at the initial stage limits the chemical stage of nucleation (formation of crystalline precipitate), then – the reaction at the interface (formation of a continuous layer of reaction products on the surface of the nuclei), and at the final stage – the growth of a continuous layer of reaction products.