Two. Salt Lake Structure and Meteorology and Hydrology
The Lower Paleozoic metamorphic rock series, Mesozoic Jurassic and Cenozoic Tertiary are widely distributed in Laoshan area around Keke Salt Lake, and Hercynian granite and various dikes are also exposed. The lake area is surrounded by Quaternary loose sediments, such as diluvial, alluvial, aeolian and lacustrine deposits. The central part of the lake area is mainly composed of gypsum and rock salt deposited in the lake. The main strata exposed horizontally in the mining area are Quaternary gravel layer, sandstone layer, loam and clayey fine sand layer. Rock salt is an inclined layer of rock salt ore, which has solid phase and liquid phase. There are at most six known rock salt ore bodies. The main seam is the first seam, which is layered, with a length of Z3 kilometers from east to west and a width of more than 4 kilometers from north to south, covering an area of about 95 square kilometers. The coal seam thickness is10 ~15m, the maximum thickness is Z7m, and most of the NaCL content is above 80%.
Keke Salt Lake has a flat surface with an altitude of about 30 10/0m, which is suitable for mechanized mining. The climate belongs to continental arid climate, with annual evaporation (2 152.2mm) much larger than annual precipitation (20 1. 1mm), low relative humidity and large temperature difference. The highest temperature is 22.9℃ from July to August every year, and the lowest temperature is from 65438+ February in the previous year to 65438+in the next year. The annual average relative humidity is 34% ~ 37%, which provides superior conditions for the formation and exploitation of recycled salt. It is an ideal salt chemical base with great development prospects and conditions for comprehensive development of lake salt.
Three. Formation of Salt Lake and Its Surrounding Environment
About/kloc-0.5 billion years ago, when the Qaidam basin was initially formed, it was originally a green kingdom with humid climate, abundant rainfall and lush plants. The steep rise of the Himalayas, like an indestructible barrier, ruthlessly blocked the humid air in the North Indian Ocean from the Qinghai-Tibet Plateau, and the climate in the Qaidam Basin changed from wet to dry, forming a large area of salt lakes in the basin. The basin is an inland centripetal water system, which originates from the rivers in the surrounding mountainous areas. Some of them leaked to the edge of the basin and disappeared, and the other part flowed into the lowlands of the basin as a lake, which evaporated strongly, making the lake a salt marsh or salt lake. There are two kinds of brines in Keke Salt Lake: surface brines and intergranular brines. The lake water is only distributed in a small area in the northeast corner and southwest corner of the salt lake, and there is only temporary surface brine in the vast lake during the rainstorm. Generally speaking, the lake area is only 1.5 square kilometers. The porosity of rock salt layer is 20% ~ 30%, and it contains intergranular brine.
Due to rational development, emphasis on sustainable development and protection of ecological environment, natural pastures are still preserved around Keke Salt Lake. In summer, herders graze on the salt lake, and there are all kinds of birds flying around the wetland by the lake. Sometimes you will see wild antelopes inhabiting the lake in droves, and the blue sky, snow-capped mountains, grasslands, sheep and salt lakes form a beautiful picture. Here, people can enjoy the natural beauty endowed by nature. Keke Salt Lake is slightly different from other salt lakes because it belongs to "dry lake". Every year, except in summer, the lake is basically dry, and vehicles can ride in the lake carefree and enjoy the beautiful scenery of the salt lake. Here you can also see the patented three-stage washing production line of lake salt, the production and production process of Wang Yi.
Four, salt lake mining and process development
Keke Salt Lake Mining Area is covered by accumulated sand or clay with a thickness of 3. About centimeters. When mining every year, the sand is cleared, the salt cover is uncovered, the salt layer is loosened by blasting, and then the primary salt layer with a thickness of 50-80 cm is broken for mining production.
There is surface brine in Keke Salt Lake in summer and autumn, and primary salt mining is open-pit operation. The salt fished out is washed in the brine in the nearby salt pit and piled on the salt cover, and then shipped after the water is naturally dried, without going through the beach drying process. The production period is generally from April to September every year, but it can also be produced in March and the year with good weather 10. At that time, the production scale was very small, the equipment was simple, and the salt mining technology was very backward. The production tools used for salt mining are "three pieces", namely shovel, spoon and rake. Manual operation is slow and inefficient, and only relying on manual salt fishing is backward, which directly affects the improvement of production level and product quality.
After 2000, after technical transformation and innovation, Wang Yi used excavators in his production, which greatly improved the production efficiency. Mechanized mining technology has been realized, and the production capacity has reached 6.5438+0 million tons. It fundamentally improves the working environment, reduces the labor intensity and reduces the production cost.
In recent years, in the face of market changes, with the increase of industrial salt demand, backward production technology can no longer meet the market demand. On the basis of introduction, digestion and absorption, the company has realized the mechanization of mining, collection, irrigation and loading through technical transformation and continuous innovation. The technological process is as follows: excavator digging in the lake-transportation without cars-cleaning-transportation by cars-cleaning and dehydration-lumping-packaging and filling-loading. Excavators enter the salt mining operation area for mining. After the first brine washing, water-insoluble substances such as sediment and silt were washed, and the contents of water-soluble impurities such as sulfate and calcium decreased. After three-stage spray washing (fresh water spray washing industrial salt) and finished product transportation, the whole production process is completed. After several months of salt water control, all physical and chemical indexes can reach the national standard.
Under the conditions of dry climate, strong evaporation, no rain, snow and surface water supply, with the saturated evaporation of brine, new salt crystals are formed on the surface of salt lake. After a few years, it is filled with new salt, and the salt can be directly mined without uncovering the cover, which reduces the mining process of new salt. As the raw salt for edible salt production, the recovered salt is crystal white, with less water-insoluble substances and other impurities, good sense and pure taste. After washing and processing, it is a truly pollution-free natural green food.
Verb (abbreviation of verb) the development prospect of salt lake
(1) Accelerating the protective development of salt lakes is a long-term strategic goal in the future. At present, Keke Salt Lake is rich in resources (1.26 million tons), with high content (the average content of sodium chloride is over 90%) and broad development prospects (it is one of the first green food production bases in China). Salt products in salt lakes are rich in trace elements (potassium sulfate, magnesium sulfate, calcium sulfate, gypsum and other resources) and salt chemicals (potassium chloride, magnesium chloride and so on). ). It is an ideal production base for high-grade edible salt and green salt of edible salt (containing various trace elements in human body), a high-quality raw salt and a real green food. In the future, we should adhere to the principles of resource conservation, scientific planning and sustainable development, rationally develop and utilize resources, improve production skills and raise technical level to ensure long-term, sustainable development and effective utilization of salt resources.
(two) continue to accelerate the pace of industrial upgrading and product structure adjustment. Continue to intensify technological transformation, rely on scientific and technological progress, extend industrial chain, improve technical level and deep processing capacity, increase varieties of salt products, and form a diversified salt chemical product system.
(3) Relying on rich resource advantages, accelerate the development of enterprises. The salt industry system will face major reforms, and the market economy situation is unpredictable. In addition, during the "Twelfth Five-Year Plan" period, the expansion, integration and reorganization of large domestic enterprises will intensify. These new changes and features also put forward new requirements and new hopes for us. We will rely on abundant resources and location advantages, intensify technological transformation, increase new products, and comprehensively utilize and develop them. Make full use of the preferential policies of the country's western development, make bold progress, seek a stronger and bigger development path, strive for new breakthroughs in the company's various economies, realize the goal of sustainable development and green development, and make Keke Salt Lake glow continuously.