Page 152 - Energy from Toxic Organic Waste for Heat and Power Generation

132 Energy from Toxic Organic Waste for Heat and Power Generation

c. Dewatering: It is the materials or wastes of naturally 1%–30% solids
by weight. The main aim is to focus the solids into a phase change or
solid form for disposal or a future treatment process. This method is
taken from filtration process.
d. Chemical precipitation: If a soluble substance is converted into an
insoluble substance by a chemical reaction or by changing the com-
position of the solvent to reduce the solubility of the substance, a
reaction occurs. Further, settling and filtration can remove the precip-
itated solids. In the process of hazardous waste materials, toxic metal is
extracted from taken source to convert it into insolvable material. In
addition to that, it contains various wastes like arsenic, copper, barium,
thallium, chromium, lead, selenium, mercury, cadmium, nickel, silver,
and zinc. The sources of waste materials in metal forms are metal plat-
ing, inorganic sources, mining materials, and various material from
electronic companies [19].
e. Chemical corrosion and Redox: When electrons are removed from
an ion or molecule, the substance gets oxidized and when electrons are
added, the substance gets reduced. This type of reactions is used in the
treatment of cyanides, sulfide, and metal-bearing wastes; in additional
to that, some of organic wastes are pesticides; phenols mainly are sulfur
containing materials. In the treatment process presence of chemical
particles, two particles are in the form of liquid solution. In rare cases,
solution reactant is slight soluble gas or solid. Maximum number of
chemicals are used as oxidizing agents, but reasonably some of agents
are used for waste treatment process. In many possible cases, oxidizing
agents such as calcium hypochlorite, sodium hypochlorite, potassium
permanganate, and hydrogen peroxide are used. Minimizing oxidizing
agents are used to extravagance waste materials presence of mercury,
chelated metals, organic metal compounds, and hexavalent compound
materials. Some of reducing agents are sodium borohydride, sulfur
dioxide, etc.; normal treatment process can need high cost to chemical
treatment and its chemical material cost also. Both the process oxidiza-
tion and reduction process lead to more suitable for low concentration
the range of less than 1% of waste.
f. Solidification and stabilization: Solidification and stabilization are
the two processes naturally used to reduce the pollutants present on
the exhaust. Those are liberated from the different processes involved
in the waste management system. It is commonly designed to improve
maximum utilization of waste material-liberated energy and physical