It is important to understand that contamina-
tion of cleaning solutions is minimal because
most of the soil has been removed during
the prerinse cycle, enabling cleaning solutions
to be used more than once. For this system to
be effective, the proper concentration of the
cleaning solution is essential. The concentra-
tion can be determined by following the
guidelines recommended by the chemical sup-
plier and the equipment vendor. Sequencing
versatility permits the timing and sequencing
of operations (acid/alkaline or alkaline/acid)
to be varied.
A tank for each chemical is provided with
reuse CIP systems. A hot-water tank or bypass
loop is necessary to save energy and water if a
hot-water rinse is used. The cleaning solution
is frequently heated with a coil.
The basic parts of a CIP reuse system are
an acid-tank, alkaline tank, fresh-water
tank, return-water tank, heating system, and
CIP feed and return pumps. Remote-con-
trolled valves and measuring devices are pro-
vided with the piping layout of this cleaning
system. The predetermined cleaning opera-
tions have automatic sequencing through a
program control unit. With this system, the
cleaning solution is transported from the
CIP unit through the production plant and
the equipment to be cleaned.
Two-tank systems for reuse of the wash
water consist of one tank for rinse water and
another for reclaiming the cleaning solution.
CIP equipment with three tanks includes one
tank for the cleaning solution, one for
reclaiming the prerinse solution, and one
for a fresh-water final rinse. Both single-use
and reuse systems require careful design and
monitoring to avoid the danger of unwanted
mixing of food products with cleaning solu-
tions (Giese, 1991).
Two tanks for alkaline cleaning com-
pounds are frequently provided for solutions
of differing concentrations. The less concen-
trated solution can be used for cleaning
tanks, other storage facilities, and pipelines.
The stronger solution is available for clean-
ing the plate heat exchanger. Pumps that feed
the cleaning compounds into the tanks are
used to automatically adjust the use of neu-
tralization tanks with automatically adjusted
acid concentrations.
Two CIP circuits can be cleaned simulta-
neously by the addition of extra CIP feed
pumps. The tank capacity is determined by
circuit volumes, temperature requirements,
and desired cleaning programs. In mecha-
nized plants, a central control console uses
remote-controlled valves to switch the clean-
ing circuits on and off. Through use of a
return water tank, water consumption of a
reuse system can be optimized. Re-circula-
tion of the cleaning solution is usually neces-
sary for best results; thus, reuse equipment
has a higher initial cost but permits opera-
tional expense savings.
The ideal CIP reuse system has the ability
to fill, empty, recirculate, heat, and dispense
contents automatically. A typical operation
of this system with a program for storage
tank and pipeline cleaning with recovery of
the cleaning solution is described in Table
11–2.Multiuse Systems
These units, which combine the features of
both single-use and reuse systems, are
designed for cleaning pipelines, tanks, and
other storage equipment that can be cleaned
effectively by the CIP principle. These
systems function through automatically con-
trolled programs that entail various combi-
nations of cleaning sequences involving
circulation of water, alkaline cleaners, acid
cleaners, and acidified rinses through the
cleaning circuits for differing time periods at
varying temperatures.
An example of a reuse CIP system is
presented in Figure 11–9. This versatile
modular unit accommodates differing CIPSanitation Equipment 205