The possibility of reducing emissions from households by using coal briquettes

Abstract

The expected demand for hard coal intended for the households will progressively be decreasing. This is directly related to the introduced anti-smog resolutions, as well as the growing level of environmental awareness. However, it should be noted, that the use of the modern home heating boilers will result in an increase in the demand for medium coal sizes. The shortfall of this type of coal is already observed on the market. Therefore, its import is necessary. One of the solutions to increase the supply of the medium coal sizes is the production of coal briquettes. Moreover, their use will consequently lead to reduced emissions. The paper presents a comparison of emissions from the combustion of coal briquettes and hard coal in home heating boilers. The briquettes were characterized by significantly lower emissions than hard coal (by 52% on average). The particulate matter emissions were lower by 70%. This may significantly contribute to improving air quality in Poland and in addition, limit the occurrence of smog. The possibility of further emission reduction by using low-emission fuels as briquette components was presented. The average relative emission reduction compared to hard coal for the analyzed fuels was estimated as follows: 62% for coal char, 57% for coke, 51% for charcoal/biocarbon, 49% for anthracite, 45% for torrefied biomass, and 33% for peat. Furthermore, the issue of the mercury content in the analyzed fuels was discussed. The lowest mercury content was found in biomass fuels, in particular biomass after thermal treatment (torrefied biomass, biocarbon, and charcoal). Fuels produced from hard coal in the pyrolysis process (coal char and coke) were characterized by very low mercury content as well.

A Prototype Reactor Promoting the Hg(0) Capture in the Simulated Flue Gas from Small-Scale Boilers by Using Copper Oxide- and Copper Sulfide-Coated Teflon Pipes

“…In addition, a person cooking in a kitchen may have a nominal inhaled dose of PM2.5 over 666 µg/m 3 during the use of low-combustion-efficiency stoves for the combustion of biomass [19]. Dziok and Penkała (2020) [20] reported that household heating boilers released nearly 99% of mercury to a stack (in power plants, even 70-85% of mercury may be bound to fly ash). The emission was coming from the combustion of hard coal and woody biomass.…”

Comparative Analysis of Combustion of Qualified Composite Fuel for the Transitional Period in the Household and Communal Sector in Poland

“…However, the process has to meet several quality requirements concerning the fuel as such. The calorific value of the fuel or the ash and sulfur content are important here, but the key parameters are: reactivity, shape and size of the fuel, shape stability, mechanical strength, and porosity [12,13,14]. The needs and requirements of the market and fuel consumers, in particular the users of top-combustion boilers, are the following: the desired fuel should be of a uniform size, combustion heat (> 25 MJ/kg), low humidity (< 7%), reduced PM2.5, NOx, SOx, CO, VOC, heavy metals emission, low sinterability, low under-combustion and reduced amount of exhaust gases per GJ of heat energy produced [15,16,17,18].…”