Ineffective or poor inter-face detection can cause pre-rinse or inter-rinse waters being routed into detergent tanks; this obviously dilutes the chemical strength but will also cool the tank temperature, requiring more energy to be supplied to maintain operating temperatures.

Pasteurisation of milk is effected at 72^oC for 15-16 seconds. Prior to plate heat exchangers being developed, traditional batch pasteurisation was achieved by heating milk to 60^oC for 20 minutes to kill off pathogens. The requirement for CIP systems to operate at temperatures around 70-80^oC with detergent wash solutions being circulated for 40-60 minutes, or longer at a concentration of 1.0-2.0% NaOH would appear excessive against batch pasteurisation parameters of 60^oC for 20 minutes (without the efficacy of a high pH medium). Effective cleaning can be achieved at lower temperatures without compromising quality.

Savings benefits:

In hard water areas, lower cleaning temperatures will reduce risk of hard water salt deposits being 'flashed-off' onto 'hot' plant surfaces when cold water is used to rinse off detergent. Lowering detergent wash temperatures will reduce the volume/time required for rinse water to 'cool' storage tanks to a temperature acceptable for them to be returned to production.

The 4 main considerations when determining the philosophy of a cleaning programme are: Time, Temperature, Concentration and Soil. Before making a change to any one of these parameters, the affect on the remaining parameters must be taken into consideration. The stringent measures  that govern and regulate the In-Site Verification Report provides greater reassurance, in terms of Quality Standards, that by optimising one CIP parameter, it will not impact on other aspects of the CIP programme. The Verification History will also provide evidence of on-going Quality Standards.

Reducing cleaning temperatures will obviously save money as less energy will be used. Reducing energy demands will also have a benefit by reducing the site's total CO2 emissions.

(Mass kg x1000) x Delta T (k) x 4.1855

Energy equivalent 1 kWh (J)

= kJs = kW

The example below demonstrates the significant savings that can be achieved by reducing cleaning temperatures by only 10^oC. Such reductions are possible with In-Site due to the system being designed to monitor and report on the 'fine detail' of every CIP operation.

EXAMPLE: CIP detergent tank (10m³) at an ambient temperature of 15^oC heated to 70^oC (before) and cost savings if tank was maintained at 60^oC (after).

BEFORE

AFTER

SAVINGS (per CIP tank)

Energy requirement

639 kWh (21.82 therms)

Energy requirement

523 kWh (17.85 therms)

based on use of Natural Gas

CO2

emissions

Energy

costs

CO₂ emissions if energy derived from Natural Gas

33.12 kg/CO₂

27.10 kg/CO₂

per annum

6.386 Tonnes

£2,021