Page 62 - Energy from Toxic Organic Waste for Heat and Power Generation

50 Energy from Toxic Organic Waste for Heat and Power Generation

concentration. Hence, color from textile wastes carries significant esthetic
importance. Most of the dyes are stable and has no effect of light or oxidiz-
ing agents. They are also not easily degradable by the conventional treat-
ment methods. Removal of dyes from the effluent is major problem in most
of textile industries [24,25].
Organohalogens—A pigment containing a covalent fluoro-carbon,
chloro-carbon, bromocarbon, or iodo-carbon bond; and toxic elements—A
pigment containing lead, cadmium, mercury, vanadium, chromium(VI),
cobalt, nickel, arsenic, antimony, or selenium involve toxic and hazardous
risks [24,25].
Organic compound (such as benzene, methane, paraffins) is made of two
elements, carbon and hydrogen, and found in coal, crude oil, natural gas,
and plant life. Hydrocarbons are used as fuels, solvents, and as raw materials
for numerous products such as dyes, pesticides, and plastics; petroleum is a
mixture of several hydrocarbons [26].

4.13 HEAT AND ENERGY GENERATION FROM TEXTILE
INDUSTRY WASTE

The heat and energy generation can be achieved by treating the wastewater
effluent using microbial fuel cells (MFCs). Also, the textile effluent can be
treated by UASB Technology (explained in Chapter 5) for energy genera-
tion. The details of MFCs are presented in the following section.

4.14 MICROBIAL FUEL CELLS
MFCs, which make use of domestic sewage, industrial effluent, leachate,
sediment, and rhizodeposits as biodegradable substrates, offer a technol-
ogy for electricity generation in addition to benefits for the environment.
Organic matter can be used as a renewable resource to generate electrons
and protons via electrochemically active bacteria in MFCs. Protons are
released into solution and electrons are produced at the anode; subse-
quently, at the interface of the cathode, electrons pass through the outer
circuit before they can reach the cathode and combine with electron
acceptors [27].
The MFC has gained much attention because of its ability to generate
power from organic or inorganic compounds via microorganisms. Around
100 years ago, the technology of generating electricity through bacteria was
found, but it did not gain much attention. Due to the ability to convert