When you decide to open a beverage or water factory, the first thing you have to do is choose the factory site. When select a site, in addition to considering the size of the factory area, traffic, but also need a water report to know if there is good water around the factory.
How do you know the water is good or not?
Commission an authoritative testing company to sample water sources and analyze the samples. The testing company will then provide a water quality inspection and analysis report. This report clearly shows the composition of the water source. Water quality report is an important criterion to judge the quality of water.
1.Why the raw water report is important?
The process flow of water treatment equipment is not constant. It is customized according to raw water quality and purified water standards. The detailed raw water report is helpful to make the best water treatment design.
The recovery rate, purified water quality, and machine’s daily operation/maintenance also depend on the raw water quality. Different enterprises choose different raw water. Even if it is all tap water, the water quality will vary in regions. If the inlet water quality is not good, it will lead to the RO membrane scratching, fouling, or oxidation. Then affects the quality of outlet water.
For the enterprises that use tap water, they can contact tap water companies to get a water report.
It is worth noting that the quality of raw water will vary with seasons and geology. We should fully consider it when designing the system. If necessary, the enterprise needs to make a raw water quality analysis every quarter.
The raw water report usually contains two parts
1. The values of heavy metals and bacteria in raw water
2. The corresponding water outlet requirements.
2.What are the main items of water report testing?
Sensory properties: color, turbidity, smell, taste, visible to the naked eye.
General chemical indexes: PH, hardness, iron, manganese, copper, zinc, aluminum, volatile phenols, anionic synthetic detergent, sulfate, chloride, total dissolved solids, and oxygen consumption.
Physical indexes: fluoride, nitrate nitrogen, selenium, cadmium, hexavalent chromium, lead, silver, formaldehyde, etc.
Bacteriological indexes: total number of bacterial, total coliform group, and fecal coliform group.
The following is the Chinese reverse osmosis pure water quality standard and test table
| Item | Nataiona Standard 1 | Nataiona Standard 2 | Ministry of construction standards | Actual measurement results | ||
| Raw Water | 1 Stage Reverse Osmosis | 2 Stage Reverese Osmosis | ||||
| Chroma | ≤5 | ≤5 | 5 degrees | ≤5 | 0 | 0 |
| Turbidity | ≤1 | ≤1 | 1NTU | 0.37 | 0 | 0 |
| Odor and taste | Imperceptible | No bad smell | Without | Without | Without | |
| Inclusion are seen in unaided eye | Must not contain | No detection | Without | Without | Without | |
| PH | ≥5.0 | 5.0-7.0 | 6.0-8.5 | 7.41 | 7.1 | 6.5 |
| Conductivity(25±1) ℃,us/cm | ≤10 | 4.88 | 1.2 | |||
| Potassium permanganate consumption (based on 02) mg / L | ≤1.0 | 2 | 0.63 | |||
| Plumbum (in pb),mg/L | ≤0.01 | 0.01 | <0.002 | <0.01 | <0.002 | |
| Arsenic(in As),mg/L | ≤0.01 | 0.01 | <0.01 | <0.005 | <0.002 | |
| Volatile phenols (based on phenol), mg / L | ≤0.002 | 0.002 | <0.002 | <0.002 | ||
| Oxygen consumption, mg / L | ≤1.0 | 1.29 | 0.81 | |||
| Trichloromethane, ug/L | ≤15 | 8.6 | <1 | |||
| Carbon tetrachloride，ug/L | ≤1.8 | 2 | <0.1 | <0.1 | ||
| Total hardness (based on calcium carbonate), mg / L | ≤450 | 300 | 127.51 | 2.5 | <1.0 | |
| Iron,mg/L | ≤0.3 | 0.2 | <0.03 | <0.02 | <0.03 | |
| Manganese,mg/L | ≤0.1 | 0.05 | <0.01 | <0.01 | <0.01 | |
| Copper,mg/L | ≤1.0 | 1 | <0.002 | <0.02 | <0.002 | |
| Zinc,mg/L | ≤1.0 | 1 | 0.016 | <0.02 | 0.061 | |
| Aluminum,mg/L | 0.2 | <0.01 | ||||
| Sulfate,mg/L | ≤250 | 36 | 2 | 1 | ||
| Chloride,mg/L | ≤250 | Based on Cl- ≤6.0 | 250 | 33.5 | 5 | 1 |
| Total dissolved solids,mg/L | ≤1000 | 500 | 238 | 5 | 1 | |
| Fluoride,mg/L | ≤1.0 | 1 | 0.602 | 0.231 | ||
| Cyanide,mg/L | ≤0.05 | Based on CN- | 0.05 | 0.002 | 0.002 | |
| Free residual chlorine,mg/L | Based on Cl- | ≥0.05 | 0.1 | <0.05 | <0.05 | |
| Selenium,mg/L | ≤0.01 | 0.01 | 0.002 | <0.001 | <0.001 | |
| Mercury,mg/L | ≤0.001 | 0.001 | <0.0002 | <0.0001 | <0.0002 | |
| Cadmium,mg/L | ≤0.01 | 0.01 | <0.001 | <0.001 | <0.001 | |
| Chromium (hexavalent),mg/L | ≤0.05 | 0.05 | <0.004 | <0.004 | ||
| Silver,mg/L | ≤0.05 | 0.05 | <0.005 | <0.01 | <0.005 | |
| Chloroform,ug/L | 30 | |||||
| Nitrate,mg/L | Based on nitrogen≤20 | Based on nitrogen 10 | <0.12 | <0.12 | ||
| Total bacterial count,cfu/ml | ≤20 | 50 | Not detectable | Not detectable | ||
| Total coliform,cfu/100ml | 0 | 0 | 0 | 0 | ||
| Fecal coliform,cfu/100ml | 0 | 0 | 0 | 0 | ||
| Remark: National standard 1 refers to GB5749-1985 Sanitary standard for drinking water ; National standard 2 refers to GB17323-1998 Bottled drinking pure water; Ministry of construction standards refers to GB5749-1985 Drinking water quality standards . |
The following is a table of the sterilization efficiency of ultraviolet germicidal lamps against common bacteria and viruses:
| Name | Time required for 100% killing (seconds) | Name | Time required for 100% killing (seconds) | |
| Bacterium | Escherichia coli | 0.36 | Mycobacterium tuberculosis | 0.41 |
| Corynebacterium diphtheriae | 0.25 | Cholera bacteria | 0.64 | |
| Tetanus bacilli | 0.33 | Pseudomonas | 0.37 | |
| Clostridium botulinum | 0.80 | Salmonellae | 0.51 | |
| Dysentery bacillus | 0.15 | Intestinal fever bacteria | 0.41 | |
| Bacillus anthracis | 0.30 | Salmonella typhimurium | 0.53 | |
| Leptospira | 0.20 | Shigella | 0.28 | |
| Legionella pneumophila | 0.20 | Staphylococcus | 1.23 | |
| Micrococcus genera | 0.4-1.53 | Streptococcus | 0.45 | |
| Virus | Adenovirus | 0.10 | Influenza virus | 0.23 |
| Phagocytic cell virus | 0.20 | Poliovirus | 0.80 | |
| Coxsackie virus | 0.08 | Rotavirus | 0.52 | |
| Echovirus | 0.73 | Tobacco mosaic virus | 16 | |
| Echovirus I | 0.75 | Hepatitis B virus(HBV) | 0.73 | |
| Mold spore | Aspergillus niger | 6.67 | Soft spore | 0.33 |
| Aspergillus | 0.73-8.80 | Penicillium | 2.93-0.87 | |
| Dung fungi | 8.0 | Penicillium toxigenic | 2.0-3.33 | |
| Mucor genera | 0.23-4.67 | Penicillium and other fungi | 0.87 | |
| Water algae | Cyanobacteria | 10-40 | Paramecium | 7.30 |
| Chlorella | 0.93 | Green algae | 1.22 | |
| Nematode eggs | 3.40 | Protozoa genus | 4-6.70 | |
| Fish diseases | Fungi | 1.60 | Infectious pancreatic diseas | 4.0 |
| Leukoderma | 2.67 | Viral hemorrhagic disease | 1.6 |
3.Example analysis of raw water report for reference.
The water source sample for this water report is groundwater. Compared with surface water, groundwater has less effect by weather and the environment. It can maintain a stable water quality state. Thus, unpolluted groundwater is ideal raw water. Besides, some groundwater, such as spring water, contains beneficial minerals. It is a big selling point for bottled water producers.
Taking this water report as an example, we will analyze each index one by one. We will take China’s product water standard as a reference here.
Color:
The test result is 10. Quartz sand filter and activated carbon filter can remove the color. The primary reverse osmosis can treat the Hazen as 0. The Hazen of water is an index for the quantitative color test of water. Suspended solids, colloids, or dissolved substances affect Hazen. The surface color is the Hazen that formed by Suspended solids. The true color is the Hazen that is formed by colloids or dissolved substances. The quantitative degree of these colors is Hazen.
| Color caused by common substances in water | |||||||
| Substances present in water | Hard water | Ferrous iron | Ferric iron | Hydrogen sulfide | Sulfur bacteria | Manganese compounds | Humate |
| The color of water | Light blue | Grey blue | Yellowish brown | Emerald green | Red | Dark red | Dark yellow or gray black |
Coliform(E.coli):
The test result in the report is absent. The total number of coliform groups in a 1L water sample is an important water quality index. It shows if the water has biological pollution (such as fecal and urine pollution). E. coli in raw water must be 0. If E. coli is detected in the water, it indicates that the water source may be contaminated by feces.
PH:
The test result in the report is 7.37, which is within the standard range. The pH value of natural mineral water is generally 7-8.5. PH value: used to indicate the pH value of water. A pH value less than 7 is acidic, a pH value greater than 7 is alkaline, the PH value of pure water is7, which is neutral. High pH value will lead to a bitter taste of water and easy scaling of water pipes and equipment. Water with a low pH value will corrode or dissolve metals and other equipment.
Turbidity:
The test result in the report is 1.1ntu, which is high. Turbidity: It is caused by mud, dust, fine organic matter, plankton, and colloidal. The degree of turbidity is turbidity, the unit is NTU. Turbidity is one of the main characteristics to judge if water is polluted in appearance. usually, these suspended substances and colloidal substances will also parasitize bacteria and viruses. The quartz sand filter can remove these impurities very well. The turbidity of drinking water should not exceed 1 NTU. And the reverse osmosis inlet water must be less than 0.5 NTU.
TDS:
The test result in the report is 539mg / L, through reverse osmosis, TDS can be below 50. TDS (total dissolved solids) is to show the total quantity(mg) of dissolved solids in 1 liter of water. The unit is ppm or mg / L, which can be measured with a TDS instrument. It also reflects the ion content in the water.
The following is the standard reference for TDS:
- WHO: TDS of human drinking water < 50
- Hong Kong: within 80-100 is acceptable
- China: tap water < 1000
- Industrial water: > 200, exceeding 300 is industrial polluted water
- Water from tap water company: 180-260
- Deep well water: 300
- General reverse osmosis water < 50
It is worth noting that TDS is not the lower the better. TDS is a value, but it is not a standard to measure water quality.
Total alkalinity:
The test result in the report is 395mg / L. There is no standard for this index. It refers to the total amount of substances in water that can neutralize with strong acids. Natural water generally takes bicarbonate ions as the main form. And weak acid salts(acetic acid, propionic acid, and hydrogen sulfuric acid) in polluted water.
Hardness:
The total hardness is 302mg/l. Total hardness refers to some metal ions that are easy to form the sediments in the water. Usually refers to the content of calcium and magnesium ions. In the report, calcium ion is 90.5mg/ L and magnesium ion is 18.4mg/ l. The hardness is a little high, indicating the risk of scaling. Sodium-ion softening can achieve the effect of softening water.
According to the different hardness, water can be classified as soft water (Max CaCO3 ＜ 60mg/l), hard water (b Max CaCO3 ＜ 180mg/L), and very hard water ( Max CaCO3 ＞ 180mg/L). Hard water is not harmful to human health. But it leads to scaling on pipe, equipment, or membrane surface.
Chloride:
The test result in the report is 11.9mg/l, which is within the standard range. Reverse osmosis can remove it well. Drinking water containing a small amount of chloride is usually non-toxic. When the chloride content exceeds 250mg / l, people can detect it through taste. when it exceeds 500mg / L, it has an impact on gastric secretion and water metabolism. Also has a corrosive effect on the water distribution system.
Sulfate:
The test result in the report is 3.2mg/l, within the standard range. Sulfate is a low toxic or non-toxic component. It widely exists in drinking water, mainly from rocks and soil. If the concentration is lower than 500mg / L, it does not affect the human body. The high concentration can cause diarrhea and affect the taste of water. Its general limit value is 250mg / L.
Iron:
The test result in the report is 0.18mg/l, which is on the high side. Manganese sand filter is a good pretreatment to reduce iron. It Can be less than 0.02mg/l after reverse osmosis. Iron affects the color, smell, and taste of water. Iron has irreversible damage to the reverse osmosis membrane. And thus reduce the service life of reverse osmosis. so it is necessary to add the manganese sand filter for iron removal before reverse osmosis.
Before the source water enters the membrane system, the iron content must be less than 0.03mg/l,
Arsenic:
The test results in the report is not detected. Arsenic is a highly toxic and carcinogenic substance. The content of arsenic in raw water must be less than 0.01mg/l. It can be less than 0.005mg/l after primary reverse osmosis.
Silica:
The test result in the report is 19.5mg/l. and there is no rigid standard for the water. Reverse osmosis can remove it. Silicon dioxide: divided into active silicon dioxide (dissolved silicon) or inactive silicon dioxide (colloidal silicon). Generally, colloidal silicon will speed up the fouling of the ultrafiltration membrane. Silica is non-toxic and insoluble in water. The mainstream water quality standards have not made explicit provisions on this index.
In General, the water source is safe. But there are still problems of high color, turbidity, hardness, and high iron content.
To ensure water safety, we recommend testing extra items:
- 1. Manganese (affecting the taste of water, and causing irreversible damage to RO membrane)
- 2. Bromide (reacting with ozone to produce carcinogenic bromate)
- 3. The total number of bacterial, pseudomonas aeruginosa, mold, yeast, and other fungi
- 4. Nitrite
- 5. Oxygen consumption. Thanks for reading here. We’d like to discuss and share with you more knowledge.
Now you must know why water quality reports are so important. If you have chosen the site, please be sure to do water quality testing. LINHO always provides you with professional water treatment solutions.
