Biomass as Raw Material for the Production of Biofuels and Chemicals

Waldemar Wójcik, Małgorzata Pawłowska, Waldemar Wójcik, Małgorzata Pawłowska

• Editorial: Routledge
• Año: 2021
• ISBN:
  9781000399615
• Edición: 1
• Categoría: Technology & Engineering
• Categoría: Chemical & Biochemical Engineering

For the power industry, biomass is just a modern name for the ancient material of plant origin that was converted into energy in the simple technology of burning. This book discusses biomass as a raw material for the production of liquid or gaseous biofuels and valuable chemicals. Such biomass processing should be beneficial from both economic and environmental points of view. Classic technologies of biogas production are still being improved, but they always generate waste that differs in terms of chemical parameters, depending on the feedstock digested. These parameters dictate the manner of their final managing. Various biotechnologies allow the use of the biomass of hydrobionts, such as cyanobacteria as a raw substance for obtaining different products, e.g. hyaluronic acid, biopolymers, fertilizers, or even drugs. Animal fats or algae can be used to produce biodiesel which in turn is used in environmentally friendly urban transport. Even municipal solid waste can be a source of useful biomass. The authors show how its volume and composition can be predicted, by which form of processing it can be converted into valuable products, as well as in which ways its negative environmental impact can be limited.

Chapter 1 The Intensity of Heat Exchange in Complexes of Organic Waste Disposal

Stanislav Y. Tkachenko, Kseniya O. Ischenko, Nataliya V. Rezydent, and Leonid G. Koval

Vinnytsia National Technical University

Dmitry I. Denesyak

Green Cool LLC

Roman B. Akselrod

Kyiv National University of Construction and Architecture

Konrad Gromaszek

Lublin University of Technology

Serzhan Mirzabayev

Academy of Logistics and Transport

Aigul Tungatarova

M. Kh. Dulaty Taraz Regional University

DOI: 10.1201/9781003177593-1

Contents

1. 1.1 Introduction
2. 1.2 Material and Research Results
3. 1.3 Conclusions
4. References

1.1 Introduction

The increase in energy efficiency of biogas plants is slowed down by the drawbacks of the methods, structures and technologies for thermal stabilization of the mixture in the bioreactor, which causes problems with temperature constancy throughout the reactor volume. It is well known that biogas plant (BGP) in the west produces more energy in the form of biogas than is required to maintain the functioning of the BGP itself (pre-heating, transportation, heat stabilization, etc.). Another problem concerns the raw materials for BGP, as it can be animal, agricultural, food and industrial wastes, and usually even mixtures of all of these. The number of variants of mixture compositions is infinite; so the study of each variant is not appropriate. This was confirmed in the conditions announced for scientific works at the XVI Minsk International Forum on Heat and Mass Exchange (http://www.itmo.by/conferences/mif), which clearly indicates that the research of the thermophysical properties of substances is not accepted and has no scientific value. For the qualitative course of the fermentation process, a rather strict compliance with the temperature mode at BGP is required. In this case, under the conditions of acceptable temperature fluctuations in the psychrophilic mode amount to ±2°C, and in thermophilic mode, the accuracy increases to ±0.5°C (Sadchikov and Kokarev, 2016). An important role is played by indirect parameters such as fraction size, substrate moisture in different seasons, and mixing intensity. Devising a rational mixing method contributes to the creation of optimal hydrodynamic and temperature conditions for the existence of the methane-forming bacteria, as well as a more efficient use of a digestion tank volume (Tropin, 2011). This leads to the development of means for evaluating the thermophysical properties and intensity of heat exchange of raw materials at the BGP, directly during the process of fermentation. There are no such plants and experiments that would cover the full range of problems described above. In practice, the methods for assessing the intensity of heat exchange under the conditions of limited information on the thermophysical properties of complex mixtures are required in order to implement both deep fundamental research and rapid analysis at the existing BGP. Such methods have emerged and developed (Tkachenko and Pishenina, 2017), and the convergent results obtained with these methods are available. It is now possible to further improve these techniques using the regular thermal mode (RTM) (Kondratev, 1954; Osipova, 1979).

The purpose of this chapter is to show how to increase the energy efficiency of heat exchange equipment by reducing the uncertainty of estimating the intensity of heat exchange in liquid multiphase mixtures, which are prone to structural changes, by improving the methods and means of implementing the experimental calculation method using the RTM. To achieve this objective, the following tasks were set: analysis of experimental data obtained on a test rig; development of a mathematical model to evaluate the effect of structure cracking and mixing on the intensification of the heat transfer process; development of recommendations to use this technique to estimate heat transfer intensities during the development of full-scale heat exchangers.

1.2 Material and Research Results

The solid fraction of pig manure was selected as a test substance. The approximate weight of a fattening pig is 85 kg. According to NTP 17-99kh (2001), under the described conditions, the humidity accounts for 75%. For research, solid manure was stirred with water to obtain different humidity. The stirring process was implemented in the following seq...