Promoting Resource Efficiency in Small & Medium size ... - UNEP

Table 60 shows rinsing criteria for the design of rinsing systems in
galvanising. The rinsing criterion is the dilution factor defined by
the concentration of the substance to be diluted in the adhering film
when taking the part out of the active bath divided by the desired final
concentration after rinsing.
Degreasing 35-100
Pickling 100-200
Anodising 2000-4000
Copper 1000
Phosphatising 2000
Nickel 3000-5000
Chrome 10000+
Table 60: Rinsing criteria in galvanising
In stamping sheet metal, the bar between the parts should be as wide as
the material is thick.
Heating steel in a furnace typically causes high losses in oil or gas fired
furnaces to the exhaust gas. The heat consumption of a typical furnace
is about 3000 kJ/kg. Heat recovery to preheat the combustion air and
improved control can reduce this by 30%. Induction heating reduces
energy requirement further to less than 2000, supra-conductive coils for
induction heating to almost 1000 kJ/kg.
9.9 Kitchen, office, sanitary use
Table 61 and Table 62 show typical water consumption for kitchen
operations and toilets.
Equipment
Commercial
dishwashers
Pre-rinse
spray valves
Commercial
steam
cookers
100
Type
Water use
Traditional Existing standard High efficiency
Savings potential
Comments
Under counter 1 – 1.8 gal/rack no standard 1 gal/rack up to 0.8 gal/rack Machines with an overall
height of less than 36“; rack
of dishes remains stationary
within machine during
sequential wash and rinse
sprays. High temp machines
are most water efficient.
Stationary single
tank door
Single tank
conveyor
Multi tank
conveyor
Handheld hosemounted
dish
sprayers
Compartment
steamers
Table 61: Benchmarks for dishwasher
1.1 – 2.2 gal/rack no standard 0.95 gal/rack up to 1.2 gal/rack Includes machines commonly
referred to as pot, pan and
utensil washer. Also applies
to machines in which the rack
revolves on an axis during the
wash and rinse cycles. High
temp machines are most water
efficient.
0.7 – 1.4 gal/rack no standard 0.7 gal/rack up to 7 gal/rack A single tank conveyor
machine has a tank for wash
water followed by a final
sanitising rinse and does not
have a pumped rinse tank.
0.54 – 1.2 gal/rack no standard 0.54 gal/rack up to 0.58 gal/rack Machines with one or more
tanks for wash water and one
or more tanks for pumped
rinse water. Followed by a final
sanitising rinse.
2 – 5 gpm 1.6 gpm at 60 psi 0.4 – 3.4 gpm
25 – 35 gal/hr no standard ENERGY STAR
qualified cookers
average 2 gal/hr
up to 33 gal/hr