Discussion on the cool and heat source for hospital clean room

With the development of science and technology, a large number of new ideas and new technologies have been accepted and applied, which has created favorable conditions for improving the medical environment and medical facilities of hospitals. At the same time, it has put forward higher requirements for hospital medical facilities. The air conditioning system faces outstanding challenges. The operating room, ICU, CCU, PICU, NICU, EICU, central supply, venous fluid distribution center, genetic reproductive center, etc. have strict requirements on temperature and humidity, and have both hot and cold demand throughout the year.

The traditional way of clean air conditioning requires two independent sets of cold and heat sources. The number of equipment is large, the initial investment is large, and the area occupied by the machine room is also large. The system, pipeline, and self-control are complicated, the operation is difficult, and the maintenance amount is large. The cold and heat sources independently consume energy and have high operating costs.

Optimization of cold and heat sources

The volume of the building for medical cleaning is usually large, and the load characteristics of the inner and outer areas vary greatly, especially in the winter or transition season. When the outer area needs to send heat, the inner area needs to be cooled all year round due to overheating. For air-conditioning systems that operate intermittently in medical clean-up projects, the inner zone should consider the problem of warm-up of the air-conditioning system during the winter.

There is cooling demand in the transition season and winter inner zone. The chiller is self-protected due to low ambient temperature and cannot start normally.

In order to meet the above-mentioned hot and cold demand for medical clean equipment projects, it is conceivable to centrally set up cold and heat sources to achieve comprehensive utilization of energy; comprehensively consider the characteristics of hot and cold load and hot water demand in the transitional season and winter medical clean equipment projects, it is recommended to use four pipes heat pump unit or small heat and cold station (6 pipes multi-function heat pump).

Four pipes multi-function heat pump unit

The four pipe multi-function heat pump unit can obtain the condensed heating hot water from the condenser while obtaining the chilled water in the evaporator, and the cold and heat imbalance parts are discharged through the balanced heat exchanger, thereby achieving continuous simultaneous cooling and heating. And only input one energy will get both cold and heat, which will greatly reduce energy consumption and reduce emissions.

Using the comprehensive energy efficiency TER to evaluate the efficiency of the unit in the simultaneous cooling and heating mode, the scroll compressor unit TER>7, the screw compressor unit TER>8. The four pipe multi-function heat pump unit integrates cold and heat sources into one, one unit takes four tubes, two are chilled water inlet and outlet, two are hot water inlet and outlet, cold and heat automatic balance, cooling capacity and heating capacity can be realized separately. 0~100% independent adjustment.

The four pipe multi-function heat pump hot and cold water unit should meet the requirements of cold and heat load in summer and winter design conditions, and should also meet the requirements of non-full load use. Therefore, there should be two (including two) independent circulation loops, the number of equipment should not be less than two, and should consider the standby unit.

Small hot and cold station

Comprehensive consideration of the entire cold load and heat load of the entire surgical department, including the cooling capacity and heat supply of the air conditioning system, the amount of hot water for bathing, brushing and dirt cleaning, and selecting a suitable centralized cold and heat source to effectively save energy. It is recommended to use a small hot and cold station (6 pipe multi-function heat pump).

The small hot and cold station is used for cooling, heating and providing sanitary water above 65 °C. It is recommended to use multi-function heat pump equipment with high-temperature heat pump technology. In principle, the boiler can be used as an auxiliary heat source in the northern part of the hospital. It has four pipe multi-function heat pump water chiller function and high temperature heat pump function. The equipment has 6 pipes, 3 independent water systems, 1 air conditioner for cooling, 1 air conditioner for heating, and 1 high temperature sanitary hot water (above 65 °C) to form a complete hot and cold supply unit, cold and hot. Automatic balancing, cooling capacity and heating capacity can be independently adjusted from 0 to 100%; heating capacity includes two independent circulation systems: air conditioning heating and high temperature sanitary hot water heating.