Facing the curious eyes of everyone, Yang Fang continued: "The water flow of this stream is actually very limited, because the water we transfer from more than a hundred kilometers is also limited, and it must support the daily life of our entire park. and water for scientific research and production.
Only excess water will be drained from the artificial lake and flow into this stream. However, as the scale of our Northwest Research Center becomes larger and larger, water consumption has also increased sharply, so less and less water flows out of the artificial lake.
In addition, this place is located in the hinterland of the Gobi desert, with harsh natural conditions and high evaporation, so the river water may have completely penetrated and evaporated after flowing out for a few hundred meters.
Therefore, we set our sights on the wastewater treatment of the entire Northwest Research Center. Every day, our Northwest Research Center produces a large amount of water for domestic and scientific research.
Except for some water that can be recycled and reused, most other water cannot meet secondary use standards. It would be a pity to emit them in vain or let them evaporate. "
What Yang Fang is talking about is actually a way to treat sewage in the northwest region or many regions. Except for the very rough direct discharge, most of the sewage now needs to be treated by sewage treatment stations before being discharged.
To put it simply, the sewage is subjected to a series of methods such as sedimentation, filtration, neutralization, and purification to make the sewage reach dischargeable standards before it can be discharged.
This does not mean that the sewage that has been treated by the sewage treatment plant has no pollution or problems. That is not the case. At most, it can only be carried out after the indicators of serious environmental pollution in the sewage meet the prescribed licensing requirements. emission.
However, sewage treatment plants require money to operate, and the cost of treating sewage is not cheap. Therefore, this will lead to many companies illegally discharging water, or the sewage treatment plant does not operate in accordance with the prescribed standards, and the treated sewage does not meet environmental protection standards, etc.
In arid areas, because there are no rivers that can be directly discharged, and in order to lower the standards for sewage discharge, another method is used to treat sewage. To put it simply, it relies on the very strong evaporation in arid areas to discharge the sewage into some pools, and then evaporate it through sunlight, turning the sewage into water vapor to evaporate.
This in itself is a very good way of purification. For example, the desalination of seawater we are accustomed to uses this method to obtain fresh water from seawater.
This sewage will evaporate under the evaporation of sunlight, and the clean water will evaporate through water vapor, and the rest will be the pollutants in the sewage.
However, this requires the establishment of many large evaporation pools, and these pools need to be well infiltrated to prevent sewage from seeping into the soil and contaminating deep groundwater.
Relying on evaporation is very cheap compared to sewage treatment plants, and it is also the most commonly used method in arid areas.
But from what Yang Fang said, it seemed like they didn't do that.
Sure enough, she smiled and said: "But in our opinion, Mr. Wu, it is really a pity to let this sewage evaporate in vain.
This is the Gobi Desert, the place with the greatest water shortage. Although these are sewage, they are also water.
Therefore, Mr. Wu thinks that this sewage cannot be wasted. Instead of just evaporating, it is better to use it rationally. "
"How to rationally use this sewage has also become a topic of our internal discussion." Shen Ning took over Yang Fang's words and said: "We have many internal opinions on the use of this sewage, and some people suggested establishing a recycling system. Reclaimed water treatment centers treat this sewage so that it can be reused.
According to their suggestions, this recyclable water treatment center can use the strong sunlight here to evaporate the sewage to obtain purer distilled water for secondary use. It can also use solar photovoltaic power plants to provide this recyclable water. The treatment center is powered so that it can operate independently and the cost of treating sewage can be reduced to a very low standard.
However, the initial construction investment was too large. All in all, it would cost several billion to complete and put this system into operation. The cost was really high, so we had to abandon this plan.
Soon, another plan was put in front of us, which was to build a large-scale sewage treatment plant consisting of a solar photovoltaic power station and a sewage evaporation treatment system to treat this sewage.
This sewage does not need to be treated so cleanly to meet human standards. It only needs to meet the discharge conditions, and then discharge it into the desert, intersect with the river, and then form an inland river in the desert. , and then we use this inland river as a water source and plant various trees around it to form this Populus euphratica forest. "
"Is this all sewage? Why do I see the water is so clear?" Deputy Director Cheng said in disbelief as he looked at the clear water flowing in the river.
"Yes," Wu Hao smiled and nodded. Then he walked to the edge of the river and squatted down. He held up the river water with his hands and showed it to several people: "Ninety percent of the water in this river is sewage treated by us through the sewage treatment plant.
Although this water cannot be used as domestic water, it can meet secondary water standards. Of course, this is also due to the unique natural environment here.
Sand itself has the ability to purify water, which is why the water is so clear.
We built a small dam at the outlet of the sewage treatment plant. This dam was built using anti-seepage technology, so it can prevent the sewage from seeping underground.
At the dam outlet, we designed a special sluice. This is an upper sluice. In the middle of the sluice, there are piles of sand from the desert. These sands are very good filtering materials. They can further filter and clarify the treated sewage, so the water flows out from the sluice. The sewage that seeps out is already very clear. "
"So that's it." Everyone couldn't help but admire after hearing this. The sand that is causing headaches here actually has the effect of filtering sewage.
Wu Hao, on the other hand, continued with a smile: "In order to prevent the filtration capacity of the sand used for filtering and infiltration from weakening over time, we regularly close the gates on both sides and replace the sand.
These sands are very rich in chemicals. We will filter, recycle, and then dispose them harmlessly to avoid environmental pollution. "
(End of chapter)
