As it will be described in other chapters, composting has been used for many years
throughout the world in the stabilization of organic residues. Initially, in the management
of municipal solid waste (MSW), the emphasis was on composting the organic fraction
of MSW; sewage sludge (biosolids) was regarded principally as a source of nitrogen and
phosphorous, and to a lesser extent of potassium for enriching the organic matter and
thus promoting the compost process (Rodale, 1943; Truman, 1949; Golueke, 1950, 1953,
1972, 1977).
throughout the world in the stabilization of organic residues. Initially, in the management
of municipal solid waste (MSW), the emphasis was on composting the organic fraction
of MSW; sewage sludge (biosolids) was regarded principally as a source of nitrogen and
phosphorous, and to a lesser extent of potassium for enriching the organic matter and
thus promoting the compost process (Rodale, 1943; Truman, 1949; Golueke, 1950, 1953,
1972, 1977).
The first medium- and large-scale processes were designed to treat the entire municipal
solid waste stream. It is possible that the designs of the facilities were appropriate at that
time since the major constituents of the MSW were of biological origin. Unfortunately,
the designs of the treatment facilities were not modified as the characteristics of the waste
changed in primarily industrialized countries. The characteristics of the waste along with
other factors led to the closure of several facilities in North America and in Western
Europe.
The second half of the 1970s witnessed a drastic shift in the emphasis of composting.
Facilities were designed to treat a number of substrates ranging from manures to the
organic fraction of MSW to biosolids. In the USA, the shift was largely a response to
a desperate need for a means of treating biosolids other than by way of incineration or
landfill. Composting seemed to meet the need, especially since biosolids treatment had
been considerably advanced, particularly with respect to dewatering. In the new setting,
biosolids were dewatered to a concentration of total solids at which composting became
feasible provided that a bulking agent was used. Although not particularly troublesome
at first, this stipulation eventually became a financial handicap. With the worsening of
the financial viability came a renewed interest in the possibility of composting refuse. It
is not surprising that the possibility of bypassing the requirement for bulking by using
the organic fraction of refuse as a bulking agent gained attention (Golueke, 1977; Cal
Recovery Systems, 1983; Goldstein, 1987).
Legislative mandates, recycling goals, protection of the water and soil resources, and
other objectives set forth by national, state, and local governments provided the impetus
for waste managers to look for alternatives to reduce the amounts of waste disposed
on the land. Given the quantities and characteristics of the wastes generated by urban
areas (i.e., relatively large quantities of organic matter), biological treatment, in particular
composting, provides a sound, cost-effective, and efficient process.
As it will be explained in future chapters, composting offers a large number of advant-
ages and few disadvantages for treating organic residues. Composting can be carried out at
different levels of technology and at different scales (from backyard to central facilities).
Furthermore, the compost product can be put to use in a great number of applications in
various geographical areas throughout the world.
a desperate need for a means of treating biosolids other than by way of incineration or
landfill. Composting seemed to meet the need, especially since biosolids treatment had
been considerably advanced, particularly with respect to dewatering. In the new setting,
biosolids were dewatered to a concentration of total solids at which composting became
feasible provided that a bulking agent was used. Although not particularly troublesome
at first, this stipulation eventually became a financial handicap. With the worsening of
the financial viability came a renewed interest in the possibility of composting refuse. It
is not surprising that the possibility of bypassing the requirement for bulking by using
the organic fraction of refuse as a bulking agent gained attention (Golueke, 1977; Cal
Recovery Systems, 1983; Goldstein, 1987).
Legislative mandates, recycling goals, protection of the water and soil resources, and
other objectives set forth by national, state, and local governments provided the impetus
for waste managers to look for alternatives to reduce the amounts of waste disposed
on the land. Given the quantities and characteristics of the wastes generated by urban
areas (i.e., relatively large quantities of organic matter), biological treatment, in particular
composting, provides a sound, cost-effective, and efficient process.
As it will be explained in future chapters, composting offers a large number of advant-
ages and few disadvantages for treating organic residues. Composting can be carried out at
different levels of technology and at different scales (from backyard to central facilities).
Furthermore, the compost product can be put to use in a great number of applications in
various geographical areas throughout the world.
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