Acids household sources

There are numerous misconceptions about the sources of various chemical elements in waste, particularly those that are potential acid formers when the waste is incinerated or mechanically converted and used as a refuse-derived fuel. For example, it is often mistakenly stated that the source of chlorine in waste, hence a potential source of HCl emissions, is poly(vinyl chloride). The relative contents of selected, potentially acid-forming elements in the organic portion of a sample of waste collected from various households in one U.S. East Coast city is given in Table 2 (17). In this city, a chief source of chlorine in the waste is NaCl, probably from food waste. 

Nickel is found in air, soil, water, food, and household objects ingestion or inhalation of nickel is common, as is dermal exposure. Recent estimates suggest that as much as 28,100 tons of nickel are introduced into the atmosphere each year from natural sources and as much as 99,800 tons from human activities. In the atmosphere, nickel is mostly suspended onto particulate matter. In natural waters, the dominant chemical species is Ni2+ in the form of (Ni(H20)6)2+. In alkaline soils, the major components of the soil solution are Ni2+ and Ni(OH)+ in acidic soils, the main solution species are Ni2+, NiS04, and NiHP04. 

In the absence of such sources of NO, indoor and outdoor concentrations are quite similar (e.g., Weschler et al., 1994), since removal of NO and N02 indoors, e.g., on surfaces, is relatively slow. However, as discussed shortly, although the surface reaction of N02 is relatively slow, it is still of interest since it generates nitrous acid (HONO). Different surfaces found inside homes have been found to have different removal rates for N02. Figure 15.4, for example, shows measured rates of removal of N02 by a number of common household materials (Spicer et al., 1989). Large variations in removal rate (and hence the formation of products such as NO and HONO see later) are evident, varying from negligible for plastic storm windows to quite large for wallboard. 

One possibility for supplying household energy is to distribute electricity from central fuel cell-based power plants to houses in the surrounding area. However, it may become cheaper to store methanol in each plant and use it in the co-generation of heat and electricity.19 Such a scheme would also make possible advantages in the distribution of lighting in households via pipes from a central light source powered by fuel cells. This type of situation may provide an application for phosphoric acid cells. 

In order to obtain the desired material properties, PVC products are treated with additives. With regard to the quantity, the phthalic esters, which are used as plasticisers, represent the most significant portion. In an indoor environment PVC occurs mostly in household products, floor coverings, wall coverings and electronic devices [69]. Since wall and floor coverings sometimes represent a major part of the surface area in a room [85], they might be a source for phthalic acid esters. The soft PVC used preferentially in wallpapers contains plasticiser portions of about 30%. These are mainly di- -butyl phthalate (DBP), di-2-ethylhexyl phthalate (DEHP) and diisononyl phthalate (DINP). 

The need to operate electrically powered tools or devices independently of stationary power sources has led to the development of a variety of different battery systems, the preference for any particular system depending on the field of application. In the case of a occasional use, for example, for electric torches in the household or for long-term applications with low current consumption such as watches or pacemaker, primary cells (zinc-carbon, alkaline manganese, or lithium-iodide cells) are chosen. For many other applications such as notebooks, MP3-players, cellular phones, or starter batteries in cars only rechargeable battery systems, for example, lithium-ion batteries or lead-acid batteries, can be considered from the point of view of cost and the environment. 

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