Feasibility Demonstration Report on the Implementation of Central Pure Water System in Hospital

DATE:2019-08-05
Number of visits:5

I. Implementation Background

Under the situation of increasingly tense water resources, as the centralized use unit of water, water saving has become the primary consideration in hospital construction. In July 2011, China Hospital Association issued the "Green Hospital Building Evaluation Criteria" as an important evaluation index for hospital energy saving. Meanwhile, Document No. 103 of the Ministry of Housing and Construction also promulgated the Announcement of Building Evaluation Standards for Green Hospitals. In recent years, the National Development and Reform Commission and the Ministry of Industry and Information Technology have intensively promulgated policies related to energy conservation and emission reduction. For the medical industry, saving water and electricity, reducing pollutant emissions and building a green hospital are the needs of assessment and management, and are also the primary conditions for hospital development and competitiveness.


The realization of domestic medical pure water mainly relies on imported single-department pure water machines, and a few use domestic single-department pure water machines. With the increasing number of divisions in the medical industry, the demand for pure water in each department is also on the rise, and the shortcomings of single-department pure water machines are gradually exposed, which is not easy to centralized management, and the investment points are low. Dispersion, high cost, insufficient water quality security and other issues. The use of central pure water in developed countries has been widely used in large medical institutions in the last century. The process of central pure water system in developed countries such as Europe, America and Japan has accounted for more than 80% of the total, and its economic benefits and advancement have been verified. For large-scale newly-built comprehensive medical institutions, it is a general trend that the medical central pure water system replaces the old decentralized single-department independent water supply equipment. Through the central purification, quality water supply system, to solve all water use in the hospital. The purified water mainframe carries on the advanced treatment to the tap water to reach the basic water quality standard which can be directly used by the direct drinking water and the inspection departments, and then supplies the tap water to the departments through the whole internal circulation pipeline network and the terminal treatment device.



II. Water Use Departments and Needs Assessment

Each Department of the hospital building has a variety of different water demand. According to different water demand, the scheme can allocate different water points according to different standards to meet the centralized management and use of the hospital.

Multi-storied building

floor

Department

purpose

Water quality/category

Water consumption

Water quality requirements

Inpatient Building

6-17

Nursing Unit

Drinking water

Primary Pure Water

18000L/h

Water Quality Standard for Drinking Water (CJ-91-2005)

1

Supply Room

Cleaning disinfector, high-pressure sterilizer

Secondary pure water

5000L/h

WS_310.3-2009 Hospital Disinfection Supply Center

Hemodialysis Center

water treatment

Independent system

4000L/h

YY-0572 Requirement

2

ICU

Hemodialysis

Independent system

Operation room

Equipment cleaning

Primary Pure Water

2000L/h

American Standard for Washing Water (<15us/cm)

Surgical brushing

Primary Pure Water

10000L/h

4

Obstetrics and Gynecology Department

Surgical brushing

Primary Pure Water

American Standard for Washing Water (<15us/cm)

Baby Bath

Primary Pure Water

3000L/h

Hygienic Standards for Drinking Water of the People's Republic of China GB5749-2006

Equipment cleaning

Primary Pure Water

7000L/h

American Standard for Washing Water (<15us/cm)

5

Pediatrics

Equipment cleaning

Primary Pure Water

American Standard for Washing Water (<15us/cm)

Baby washing

Primary Pure Water

2000L/h

Hygienic Standards for Drinking Water of the People's Republic of China GB5749-2006

Outpatient Building

1

Child protection

Swimming and Bathing for Children

Primary Pure Water

3000L/h

Hygienic Standards for Drinking Water of the People's Republic of China GB5749-2006

2

Radiology Department

Water for endoscopy and DSA catheter flushing

Ultra pure water

800L/h

National Standard "GB6682-2008"

3

Clinical Laboratory

Water for the preparation of biochemical instruments and reagents

Ultra pure water

2000L/h

National Standard "GB6682-2008"

4

Otolaryngology

Dental chair

Secondary pure water

800L/h

American Standard for Washing Water (<15us/cm)

endoscope

Equipment cleaning

Secondary pure water

600L/h

American Standard for Washing Water (<15us/cm)

Operation room

Equipment cleaning

Secondary pure water

1200L/h

American Standard for Washing Water (<15us/cm)

Surgical brushing

Secondary pure water

American Standard for Washing Water (<15us/cm)

Ward Building Lobby/Hemodialysis/ICU/Pediatrics/Clinic Building

Drinking

Drinking water

600L/h

Water Quality Standard for Drinking Water (CJ-91-2005)



3. Principles for the Design of Central Pure Water System

1. Long-term planning: Central pure water system should consider the water demand of full-load operation of hospitals.

2. Emergency plan: More than two systems should be considered to run in parallel.

3. Medical characteristics: Fully considering the requirements and standards of medical water use, the system should meet the hygienic standards.

4. Importance of pipe network system: microbial control of complex pipe network and low-cost operational disinfection method.

5. Long-term stability: How to maintain the long-term stability of water quality is the key to the success of the system.

6. Public safety: The level of equipment management should be considered.

7. Sensory control: Because the system participates in the medical process, infection control is a factor that must be considered.

8. Recovery system: Graded discharge of wastewater, channel discharge of recoverable wastewater and non-recoverable wastewater are key considerations of recovery system.



IV. Design of Central Pure Water System

1. General design description

The maximum water supply of medical pure water for 8000 beds is tentatively set at 50 M3/h, and two 25M3/h systems run in parallel. Coverage area includes hemodialysis center, pathology center, laboratory center, supply center, operation center, endoscope center, ICU, dentistry, obstetrics, emergency, water purification and other pure water departments. The specific water quantity should be calculated according to the actual water consumption statistics of the departments.

2. Process Flow Design

The system is divided into two parts: water-making system and distribution system. The basic technology of water-making system is reverse osmosis desalination process. Source water buffering, multi-media filtration, activated carbon filtration, softening system, 5-micron security filtration and primary reverse osmosis are the basic pure water supply, which can be used for cleaning water and drinking water. The water for hemodialysis is supplied by post-stage two-stage reverse osmosis direct water supply, and the water for laboratory is supplied by post-stage two-stage reverse osmosis + EDI ultra-pure water system.

Distribution system adopts sanitary level supply system, tank body and distribution pipeline use sanitary level material above SUS304, all pump valves adopt double backup, which can provide emergency uninterrupted water supply. Distribution pipeline adopts welded hygienic grade pipeline to avoid leakage after aging of sealing ring of pressure joint pipeline, leading to system scrap.

The system uses thermal disinfection for routine disinfection. It can regularly and automatically carry out disinfection procedures and disinfect the distribution network. It is characterized by low cost and no chemical residues. The system must establish a complete disinfection standard, adjust the disinfection time according to the water characteristics of the departments, keep the long-term distribution pipe network clean and hygienic, and meet the requirements of microbial control.

The system wastewater recovery can be divided into two levels. One is the conventional wastewater recyclable part of the system, accounting for 90% of the total wastewater discharged. It is supplemented to the hospital washing and greening water supply system through the wastewater recovery system. The other part is the non-recoverable part of the softened brine, which accounts for about 10% of the total discharge of the system. It is high brine and is directly discharged into the hospital sewage treatment system.

3. Benefit analysis

(1) Water budget: the estimated water consumption of 8000 beds is 50M3/H, water consumption is 500 M3/D per day, tap water is 1000 M3/D and wastewater is 500M3/D.

(2) The utilization rate of equipment water in single department is less than 50%, that is, the discharge amount is 500 M3/D. After using the central pure water system, the amount of wastewater discharged is 50M3/D.

(3) Direct cost savings calculation every year: the water saving of central pure water is 450 M3/D per day and the direct cost is 1400 yuan/day compared with that of single-department water-using equipment. The medical sewage treatment cost of 450 M3/D is 4500 yuan per day, and the two items add up to 5900 yuan per day. The annual direct cost savings are 5900 * 365 = 2153500 yuan.

(4) Hidden cost: The hidden cost saved every year is quite objective. The electricity cost of single-department system is huge. The maintenance cost of single-department system is over one million. It needs ten separate rooms to store equipment, ten different department managers, various consumables, and the price is difficult to control. Dependence and so on can cause huge costs. Implicit conservatism is estimated at over 2 million.


Based on the benefit analysis, the conservative estimate of the central water system can save more than 4 million yuan per year for hospitals.