37results about How to "Reduce heavy metal activity" patented technology

The invention discloses a planting method of flax in heavy-metal contaminated soil. The method comprises the following steps of: A, preparing soil and building a field, and applying passivator to reduce activity of heavy metal in the soil; B, selecting a specific flax variety with strong heavy metal contamination resistance, sowing in enough amount at proper time to guarantee full seedlings; C, rationally and closely planting, intertilling / weeding / topdressing in time to culture effective robust plants; and D, reinforcing prevention and control of diseases and insect pests, harvesting at proper time, and drying in the sun and storing appropriately. By the flax planting method, the average yields of raw stems in light, medium and heavy contaminated soil is respectively 308.2+ / -29.0, 283.2+ / -30.3 and 254.7+ / -28.6kg / mu, which reaches the high-yield level of the flax growing areas in South China; and the content of heavy metal in raw stem coarse fiber can be controlled in a range of related standard limit, so that agricultural safety and effective utilization of heavy metal contaminated soil can be realized. The method is simple in technology and practical, and has wide application prospect in broad heavy metal contaminated areas.

The invention discloses a method for planting kenaf on heavy metal contaminated soil. The method includes the following steps: A, preparing the land and building an area, and applying an passivant to reduce the activity of soil heavy metal; B, selecting a specific kenaf variety with high heavy metal pollution resistant capacity, sowing sufficiently in due time, and guaranteeing a full stand through one sawing; C, determining suitable close planting, performing thinning and final singling in due time, and reserving basic seedlings; D, intertilling and weeding timely, topdressing and irrigating reasonably, and cultivating effective strong plants; and E, strengthening pest control and achieving high yield of the kenaf. The original kenaf outputs of mild, moderate and serious contaminated kenaf gardens are 276.2+ / -25.5, 247.6+ / -23.4 and 220.9+ / -21.2kg / mu respectively when the method is used for planting the kenaf, the high yield level in southern kenaf areas in our country is reached, content of heavy metal in the original kenaf can be controlled within a relative standard limit, agricultural safety and efficient utilization of the heavy metal contaminated soil are achieved, the technique is simple and convenient, the method is easy to implement, and an extremely wide application prospect is provided in vast heavy metal contaminated areas.

The invention belongs to the field of soil pollution control, and discloses a passivation restoration agent for arsenic-cadmium compound polluted soil and its preparation method and application method, which uses vermicompost to enrich organic matter, realizes the adsorption and complexation of cadmium, and utilizes zero-valent iron in the The iron (hydroxide) oxide formed in the soil undergoes an adsorption precipitation reaction with arsenic, thereby realizing the simultaneous passivation of arsenic and cadmium. In addition, vermicompost can significantly improve soil quality, and can comprehensively treat arsenic-cadmium compound-contaminated soil. On the one hand, zero-valent iron, a strong reducing agent, is easily oxidized to form amorphous iron (hydroxide) oxides, providing more adsorption sites for arsenic and cadmium; on the other hand, vermicompost provides more organic matter in the soil, increasing The cation exchange capacity increases soil pH, which is beneficial to the adsorption and fixation of cadmium and reduces the activity. In addition, vermicompost and iron are also partially combined to form iron oxide-organic carbon complexes, which also help the soil to fix carbon and improve soil quality.