Ventilation of potato storage. Section II

Contents

Contents of the ׃

6. Heating and ventilation section

6.1. General part

6.2. Heating and heat supply

6.3. Ventilation

6.4. Explosion and fire safety measures

6.5. Automatic throttling, blocking, and dispatching

6.6. Protection of atmospheric air from pollution

6. Heating and ventilation

General part

The project of heating and ventilation of a potato storage for 2000 tons in the village of Kurilovichi, Mostovsky district, Grodno region, was carried out in accordance with NSS 4.02.01- 03 "Heating, ventilation and air conditioning."

Climatological data for

calculation of heating and ventilation systems for Grodno.

Cold period:

average ambient temperature tn ° С for designing heating and ventilation (coldest five days) 22 ° С;

a specific enthalpy of 20.5 kJ/kg;

average wind speed 4.3 m/s;

average temperature of heating period tn 0.1 ° С;

duration of heating period 194 days;

average relative humidity 85%;

barometric pressure 990 hPa;

Warm period:

ambient air temperature + 21.7 ° С;

a specific enthalpy of 47.6 kJ/kg;

wind speed 2.6 m/s.

- design parameters of internal air in rooms are accepted

in accordance with the Job Specification.

Thermal resistance of enclosing structures:

external walls and coating R = 3 m ² ° С/W;

All basic parameters are listed on the General Data project sheet.

Operating mode - 270 days per year in shift 3, shift duration 8 hours

Heating and heat supply

Water heating of the building is not provided. The temperature in the storage chambers is maintained due to the heat of the stored products .

Ventilation

Ventilation of the building is influential with natural and mechanical motive. Air exchanges in the potato storage are accepted according to the technological task. Natural extraction from storage sections by BE1BE4 systems. Inflow is designed with recirculation by mechanical systems P1P4.

Active ventilation systems are adopted in the potato storage. Steel semicircular perforated sectional semicircular attachment air ducts are adopted for air distribution in potato mass.

Air is supplied to pressure corridors and air ducts by axial reversing fans "Cyclone" M70 with working diameter of 1250 mm. Air flow 66000/30600 m ³/h at the created pressure of 300Pa. Fans are equipped with safety grids and automatic shutters .

The project provided installation of entrance and output P1.1P1.4 and VE1VE4 valves of 2800х1200 mm in size for an admission and production of air in the mixture camera.

Valves shall be equipped with perimeter heat tracing to avoid possible fitting of valves to the frame in frosty weather. Valves are opened and closed automatically depending on ambient air temperature and microclimate in the storage.

Ventilation equipment complete with automation, providing microclimate in storage sections and cooled chambers, is supplied according to the equipment analogue (Germany or Holland).

Explosion and fire safety measures

The project was carried out in accordance with the requirements of the NSS Chapter 4.02.01- 03 in terms of fire prevention measures. The design provides for grounding of ventilation equipment and air ducts (see section EM) and disconnection of ventilation systems in case of fire (see section AK).

Automatic throttling, blocking, and dispatching

The project provides an automation system for ventilation plants for regulating air flows, temperatures and humidity, taking into account the peculiarities of the potato storage in the autumn-winter-spring periods. To collect data on microclimate parameters, a set of digital sensors is installed to monitor deviations from a given microclimate and timely corrective action. The system is equipped with the following sensors:

product temperature sensors - 20 pcs, temperature sensors in the ventilation channel - 1 for each chamber or section. temperature and ambient humidity sensors -1 pcs and CO2 carbon dioxide sensor, measuring area 02%. With this sensor, the microcomputer controller can adjust the CO2 content of the storage by supplying outside air. This may further reduce the temperature of the product in the stack.

Electric control systems are provided for 2 fans of 4 electric drives for valves, as well as for 2 frost protection thermostats. In addition, there is a monitoring device for phase disconnection and voltage decline complete with a disconnection relay, an element for switching the control mode of the suction automation system of the reverse mode of fans (manual mode/automation).

This element is mounted in the control cabinet. Valves shall be equipped with perimeter heat tracing to avoid possible fitting of valves to the frame in frosty weather (control element for valve belt heaters). Valves are opened and closed automatically depending on ambient air temperature and microclimate in the section.

Special software (ASW) is provided for data transfer between microprocessor controller and personal computer, with possibility of data storage and printing, remote control of storage mode and modular controller, graphic image and data analysis.

Protection of atmospheric air from pollution

Excessive heat and moisture vapors are industrial hazards, so additional cleaning of the emitted air is not required.