1. Andy Smith – Star Manchester
Industrial Refrigeration Plant Operating & Aftercare - What’s The Cost ?
Andy Smith – Star Manchester
Industrial Refrigeration Plant Operating & Aftercare - What's The cost.
In this presentation we look at some of the costs associated with owning and operating industrial refrigeration plants and how these can be affected depending on operating factors (energy etc) and aftercare regimes ( maintenance etc), not just the capital cost.
We will also compare the more Traditional Types maintenance with Condition Base Maintenance (CBM) regimes.
Within CBM, we look in detail at some oil samples, plus Ammonia Refrigerant Quality analysis (ARQ’s) from a national UK survey we under took on 9 industrial refrigeration systems and show what end-users have found, on operating costs and temperatures.

2. Total Cost Of Ownership
Capital
Aftercare
Operating
Total Cost Of Ownership
1) A number of factors affect the total cost of owning an industrial refrigeration plant, equipment capital cost is a relatively small part of 15%, Aftercare (maintenance) is around 20%, the most significant being Operating 65% and the majority of this is energy (power consumption).
2) So if for example end users wanted to make a saving (say 5 or 10%) anywhere it would be logical to focus on the largest percentage, which is Operating.

3. Aftercare Comparison Type B Type A Reliability Efficiency
We compared a relatively low cost traditional maintenance regime Type A which resulted in low reliability and poor efficiency with a slightly higher level, quality, condition based maintenance regime and clearly demonstrated that proper aftercare is not just a cost but a proven cost benefit investment by the resulting high reliability and improved efficiency which drove down the overall operation costs of the plant.
Reliability
Efficiency
Operating Cost

4. Aftercare Comparison Type A Type B Running Costs / Month (£,000)
Annual Running Cost Comparison 70
Type A 60
£10k savings per month 50
Type B
AfterCare – Comparison.
This is the case in point with the numbers;
Type A was the traditional type maintenance regime.
Type B is a tailor made maintenance schedule based around Condition Based Maintenance.
As you can see the cost savings were significant. 40
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Month

5. Aftercare - Traditional Maintenance
Site Labour Intensive.
Invasive.
Fixed/Manufacturers led schedules.
Aftercare – Traditional Type Maintenance
1) Traditional type Maintenance, is usually based around fixed schedules, irrespective of the system use, its application and how the system is operating, and is historically site labour intensive.
2) Including things like fixed schedules for oil and filter changes whether the system needs it or not. 5

6. Aftercare – Condition Based Maintenance
CBM
AfterCare – Condition based Maintenance (CBM)
Is much more evidence based on actual plant data rather than what the O&M dictates:
There are several methods and techniques to implementing CBM here are 5 of these:-
VA – Regular Vibration Monitoring
COP - System Performance checks, local or remote.
LA - Regular Laser Alignment
OA - Regular Oil samples
ARQ - Ammonia Refrigerant Quality analysis

7. Oil Analysis - System History
This is from a large R22 flooded system on a single screw compressor:
Sample 4 was taken at the start of the month, followed later in the month by double checking with sample 5. We see high, iron, PQ, and high water + free water.
Based on this evidence we changed oil filters, re sampled again and if we look at sample 6, all is ok.
We then took a further sample to double check all was okay, however sample 7 was found contaminated again with water, and iron is on Amber, why? No invasive work has happen to this plant, so where had the water come from?
The oil analysis was actually a symptom of a fault in the plant control system, liquid refrigerant from the surge drum, had come back to the compressor, this refrigerant would over time boil off leaving the water and iron to contaminate the oil charge.

8. Oil Analysis – High Insoluble's
(The insoluble's test measures the total insoluble materials in an oil sample, that is, all solid or liquid materials that are not soluble (won't mix) in oil. Virgin oil shouldn't have any insoluble materials in it)
This is from a large Ammonia cold storage and distribution plant:
Sample 8 shows High Insoluble's, so a second “Check” sample (9) was taken, still showing high Insoluble's.
Based on this the Oil filter was changed, and looking at sample 10, insoluble's had reduced.
However, in sample 11 insoluble's were starting to rise again.
So what was causes?

9. Oil Analysis - High Insoluble's
Faulty Coalescer
New Coalescer
Oil Analysis – High Insoluble's
Found faulty Coalescer in oil separator - glue bonding had failed.
Picture new Coalescer.
So again issues detected in the oil analysis were the symptom of a significant problem within the refrigeration plant.

10. Ammonia Refrigerant Quality Checks – (ARQ)
4 systems had water below 1%
ARQ’s (Ammonia Refrigerant Quality Analysis)
1) We carried out a Survey on 9 industrial ammonia refrigeration plants in UK. These sites used a variety of maintenance regimes, some implemented in house some used a third party.
2) Four systems were found to have water contamination of below 1%, which is acceptable/normal.
3) One system was found to have Ammonium Carbonate contamination due to second hand equipment which had previously been working on HCFC’ refrigerants (R404a), being retrofitted with ammonia with out been fully cleaned.
4) Four systems were found to have high levels of water contamination.
1 system had Ammonium Carbonate
4 systems had water from 1.5 to 24%

11. Refrigeration Capacity – Power Consumption
Ref Cap
Energy
ARQ’s (Ammonia Refrigerant Quality Checks)
1) Here we see how if we increase the water content in the refrigerant that the systems refrigeration capacity will go down. For every 1% water refrigeration capacity will reduce by 1%.
2) We also see that water contamination will increase the energy that the system uses. Again for every 1% water this will increase energy consumption by 0.5%.
Water %

12. Water Contamination Surge Drum A - 10 to 12% Surge Drum B - 20 to 24%
ARQ’s Water Contamination:
The samples here are from a large common Ammonia plant with two LT surge drums, Drum A & B.
In drum A we found water contamination of 10 to 12%, and in drum B contamination of 20 to 24%.

13. Water Removed Surge Drum A -118 litres Surge Drum B -512 Litres
ARQ’s Water Removed
So the water was removed from the system utilizing specialist ammonia refrigerant drying equipment and you can see the out put here:
Drum “A” – a total of 118 liters of water was removed.
Drum “B” – a total of 512 liters of water was removed.
What is interesting is that this plant was working without any obvious issues apart from the fact it was inefficient and running 24/7 with these significant amounts of refrigerant contamination.

14. Cold Store Temperature
What The End User Found
Cost
The system was measured before and after the decontamination of the refrigerant and found to have significant improvements in cold store temperature and power consumption.
Liquid Δt
Cold Store Temperature
Energy

15. Star Refrigeration – From Humble Beginnings to the Natural Choice
Pioneering Natural Refrigeration Technology since 1970
More than 300 staff in 11 locations across the UK and a number of agents in Europe and Asia
Has expanded from an industrial refrigeration company to a multi-faceted engineering group
Pioneering development of sustainable solutions & natural refrigeration technology
The Star Refrigeration group of companies offer a diverse range of products and services including design, manufacturing, contracting, aftercare, consultancy and training.
Founded in 1970 by two mechanical engineers, Anthony Brown and Dr Forbes Pearson, and operating from the later home in Glasgow, Star Refrigeration first steps in the industrial refrigeration and heating business were small and tentative, after the two men were made redundant. But fast-forward 43 years, and the company has mature into a diverse business group with more than 300 staff in 11 locations across the UK and a number of agents in Europe and Asia - and it is the largest and most successful independent cooling and heating contractor in the UK.
The largest and most successful independent cooling and heating contractor in the UK
Star Refrigeration – From Humble Beginnings to the Natural Choice

16. Q
& A
Q & A