Is fertilizers in drums? No fumes?
Do we need to have detectors for leakage?
Need to establish if it is corrosive (I think it is) and then comply with provisions of Table 307.7 and 414.2.4 of IBC2003.
Corrosive exhaust need SS ductwork, fan protection enamel, motor out of air stream.
Freeze...
Sorry. I meant 30% Hot deck- 70% cold deck.
Please note that system operation depends to the mixing box function, system configuration, and other factors.
A system I designed last year, would reset hot deck temperature in summer from 105 to 55 in order to provide the required "ventilation" air...
I understand you are not concern about winter operation when there is ra eal need for heat. Sounds odd. Winter total load is block heating load plus heating the air from cold deck.
In summer, hot OA can provide you the required heat.
As a rule of thumb, 70% of the total air should be heated...
Here in US it is same situation except; that there are incentives or tax deductions being paid by government(s) that make a project closer to be economical.
Ther are also cases of private organizations, chemical factories, utility generators that need to advertise for their project being green...
It depends to the size of the unit and the working SP.
A high working Sp of a AHU will blw out lots of air and creates high noise. Better to have a trap.
I think your client likes to know if there is any leakage around the filter or not. Such test includes spraying aeosel before filter and measuring number of particles after the filter. Special tecnicians know the detail how to do this. As a designer you must provide proper ductwork on two sides...