Building facade ecological interception system and building facade rainwater ecological interception method

Abstract

The invention relates to the technical field of sponge city building rainwater management, and provides a building facade ecological interception system and a building facade rainwater ecological interception method, and the system comprises a source emission reduction layer which comprises a plurality of layers of greening hanging pot assemblies which are arranged along a building facade and have a density gradient of being sparse at the upper part and dense at the lower part and are used for planting plants; each greening hanging pot assembly is filled with a water-permeable substrate, and a capillary medium compounded by coco coir and vermiculite is embedded in each greening hanging pot assembly; the process control layer comprises a vertical flow guide groove correspondingly connected with percolation holes in the bottom of the greening hanging pot assembly, a transverse bent flow channel connected with the vertical flow guide groove, and tail end flow dividing branches connected with the two ends of the transverse bent flow channel; the tail end utilization layer comprises a water storage and recycling unit for collecting and purifying rainwater and an underground capillary percolation well for permeating the rainwater into deep soil, and the water storage and recycling unit and the underground capillary percolation well are respectively connected with one tail end shunting branch. Through cooperation of ecological interception and engineering diversion, rainwater slow flow permeation and resource recycling of the building facade are achieved, and climate regulation and carbon sink improvement are both considered.

Description

Technical Field

[0001] This invention relates to the field of building rainwater management technology for sponge cities, and in particular to an ecological interception system and method for building facade rainwater. Background Technology

[0002] With the acceleration of urbanization, the hardening of urban underlying surfaces has led to a significant increase in the stormwater runoff coefficient. Problems such as urban flooding, non-point source pollution, water shortages, and the urban heat island effect caused by the traditional "rapid drainage" model are becoming increasingly prominent. The sponge city concept, with its core principle of "infiltration, retention, storage, purification, utilization, and drainage," emphasizes the combination of natural and artificial measures to achieve the natural accumulation, infiltration, purification, and recycling of rainwater.

[0003] In the sponge city technology system, buildings, as basic urban units, have roof and facade rainwater management as a key link in source reduction. Existing building rainwater treatment technologies mainly include: (1) Green roof technology. Green roofs can reduce roof runoff by retaining rainwater through planting substrates and plant layers, but they have the following limitations: First, they are only for horizontal roofs and do not make full use of the building facade space; second, the substrate layer is thick (usually 10-30cm), which requires high building load; third, the single plant configuration lacks layered synergy, and has limited ability to reduce the impact of rainfall and adsorb pollutants.

[0004] (2) Vertical greening technology. Vertical greening systems form green coverage by arranging planting containers on building facades, and their main functions are landscaping and heat island mitigation. Existing vertical greening technologies focus on plant selection and irrigation systems, such as using drip irrigation or seepage irrigation to maintain plant growth, but they are not deeply coupled with rainwater collection and purification functions; although some technologies have rainwater collection troughs, they lack the coordinated design of graded diversion and capillary infiltration, resulting in low rainwater runoff control efficiency and failing to form a complete chain of "retention-infiltration-purification-use".

[0005] (3) Rain gardens and bioretention facilities. Rain gardens purify rainwater through a plant-soil-microbe system. They are suitable for site-scale applications, but they are ground-level facilities that occupy land resources and cannot be integrated with building facades to achieve three-dimensional rainwater management.

[0006] (4) Combined rainwater harvesting system. Some traditional solutions simply combine greening with rainwater harvesting, such as setting up a water collection pipe connected to the bottom of the planting trough. However, there are the following problems: First, the plant configuration is not optimized according to the rainwater runoff path, resulting in low interception efficiency; second, there is a lack of graded diversion structure, resulting in serious overflow during heavy rain; third, the capillary infiltration principle is not used to achieve slow release of rainwater and soil replenishment, resulting in low water resource utilization.

[0007] In summary, the aforementioned traditional solutions suffer from problems such as limited functionality or insufficient space utilization. Furthermore, the ecological and engineering measures are relatively disconnected, making it difficult to simultaneously meet the multi-objective requirements of sponge cities—infiltration, retention, storage, purification, utilization, and drainage. They also fail to fully leverage the microclimate regulation and carbon sequestration functions of the plant ecosystem. Therefore, there is an urgent need for a building facade rainwater management system that integrates source interception, process control, and end-of-pipe utilization, while also possessing microclimate regulation and carbon sequestration functions. Summary of the Invention

[0008] The purpose of this invention is to solve at least one technical problem in the background art and to provide an ecological interception system for building facades and an ecological interception method for rainwater on building facades.

[0009] To achieve the above objectives, the present invention provides an ecological interception system for building facades, comprising: The source reduction layer includes: a multi-layered greening hanging pot assembly with a density gradient of sparse upper and dense lower plants arranged along the building facade, with each layer of greening hanging pot assembly arranged in a staggered manner; each greening hanging pot assembly is filled with a permeable substrate, and a capillary medium composed of coconut coir and vermiculite is embedded between the surface planting soil and the lower infiltration layer, forming a three-dimensional infiltration structure of plant roots, permeable substrate and capillary medium; The process control layer includes: a vertical guide channel connected to the infiltration holes at the bottom of the greening hanging pot assembly, a transverse curved flow channel connected to the bottom of the vertical guide channel, and end branch channels connected to both ends of the transverse curved flow channel; the inner wall of the vertical guide channel is lined with a modified geotextile and capillary fiber bundle composite lining, and the bottom and side walls of the transverse curved flow channel are lined with a zeolite and ceramsite capillary composite layer. The end-of-pipe utilization layer includes a water storage and reuse unit for collecting and purifying rainwater and an underground capillary infiltration well for permeating rainwater into deeper soil, each connected to one of the aforementioned end-of-pipe branch lines.

[0010] According to one aspect of the present invention, the greening hanging planter assembly is designed for planting tiered plants, including: The upper tall-stemmed interception layer includes one or more of the following: Miscanthus sinensis, Muhly grass, and Amorphophallus aurantiacus, combined with string plants and trailing ivy, with a plant spacing of 20-30cm. The middle and low adsorption layer includes one or more of the following: Buxus microphylla, Spiraea japonica, and Coreopsis grandiflora, with a plant spacing of 15-20cm. The lower creeping buffer layer includes one or more of Sedum lineare, Sedum sarmentosum, and mosses, with a plant spacing of 10-15cm.

[0011] According to one aspect of the invention, a semi-blank layer is provided between every 3-4 layers of greening hanging pot components. The semi-blank layer is planted only with ground cover plants and has a drainage gap reserved. The drainage gap guides a portion of the rainwater to flow into the vertical drainage channel.

[0012] According to one aspect of the invention, the permeable matrix is ​​composed of humus, perlite, and coarse sand in a volume ratio of 3:2:1.

[0013] According to one aspect of the present invention, the composite capillary medium of coconut coir and vermiculite has a particle size of 0.5-2 mm, a porosity of 60%-70%, and a thickness of 5-8 cm.

[0014] According to one aspect of the present invention, the vertical guide channel is designed with a structure that is wider at the top and narrower at the bottom, with an upper opening width of 20cm and a lower opening width of 10cm. A first diversion port is provided on it, and one first diversion port is provided for every three layers of greening hanging pot components. A capillary water-blocking strip with a height of 3cm is provided at the first diversion port, and the capillary water-blocking strip has built-in capillary fibers.

[0015] According to one aspect of the present invention, a flow regulating valve and a capillary permeation disc are provided at the connection between the bottom of the vertical guide channel and the transverse curved flow channel; The capillary infiltration plate is made of porous ceramic material. Some rainwater is discharged through the horizontally curved channel, and some rainwater infiltrates into the shallow soil underground through the capillary infiltration plate.

[0016] According to one aspect of the present invention, the capillary bundles in the modified geotextile and capillary bundle composite lining have a diameter of 0.1-0.3 mm and a length of 10-15 cm.

[0017] According to one aspect of the present invention, the zeolite and ceramsite capillary composite layer has a particle size of 2-5 mm, a capillary porosity of 40%, and a thickness of 10-15 cm.

[0018] According to one aspect of the invention, the underground capillary infiltration well has a diameter of 50 cm and a depth of 1.5-2 m, and is filled with gravel and biochar capillary media.

[0019] To achieve the above objectives, the present invention also provides a method for ecological interception of rainwater on building facades, comprising: Source interception: Rainwater is intercepted and initially purified by multi-layered greening hanging pot components arranged along the building facade with a density gradient of sparse at the top and dense at the bottom. After being intercepted by the plants, the rainwater diffuses laterally and penetrates vertically through the composite capillary medium of coconut coir and vermiculite. Process control: Rainwater intercepted at the source enters the vertical guide channel. Part of it infiltrates the backfill soil around the channel wall through the modified geotextile and capillary fiber bundle composite liner, while the other part flows downward along the vertical guide channel. It then enters the transverse curved channel and infiltrates into the surrounding soil through the zeolite and ceramsite capillary composite layer, while the residual pollutants are degraded by the microorganisms in the pores. End-of-pipe utilization: Rainwater that has undergone process control is diverted through end-of-pipe branches, with one part entering the water storage and reuse unit and the other part entering underground capillary infiltration wells to replenish groundwater.

[0020] According to the present invention, the invention achieves a reduction in rainwater runoff velocity and cumulative runoff volume through the synergistic effect of the multi-layered greening hanging pot assembly with a sparse upper layer and a dense lower layer, and the three-level flow guiding structure within the greening hanging pot assembly; the purified rainwater achieves a higher reuse rate through the water storage and reuse unit, and is used for greening irrigation, greenway flushing, etc. At the same time, groundwater is replenished through underground capillary infiltration wells, forming a dual-path resource allocation of use and infiltration, which alleviates the problems of urban water shortage and groundwater level decline.

[0021] Through a three-dimensional infiltration structure of plant roots, substrate and capillary media, lateral infiltration of modified geotextile and capillary fiber bundle composite lining, microbial degradation of zeolite and ceramsite capillary composite layer, and biochar adsorption in underground infiltration wells, rainwater is purified in multiple stages. The purification process relies on plant physiological activities and microbial action to form an ecological self-circulation and reduce dependence on chemical treatment.

[0022] By using the shading and cooling effect of the upper-layer tall plants, the transpiration and humidification effect of the middle-layer plants, and the water retention and evaporation reduction effect of the lower-layer plants, the building facade temperature can be seasonally adaptively adjusted: reducing the exterior wall temperature in summer, ensuring light penetration in winter, maintaining the facade humidity balance throughout the year, improving the building thermal environment and mitigating the urban heat island effect.

[0023] By utilizing the light gradient of upper, middle, and lower layers of plants and coordinating photosynthetic carbon sequestration, the overall carbon sequestration capacity of the system is enhanced; at the same time, relying on the seasonal changes of plants to form a rich facade landscape, the unity of ecological function and visual aesthetics is achieved, contributing to the carbon balance and ecological quality improvement of sponge cities.

[0024] The system achieves automatic regulation under different rainfall intensities by utilizing the self-driving characteristics of capillary permeation, the hydraulic self-adaptation of the flow regulating valve, and the working condition adaptation of the graded flow guiding structure; the modular structure and durable material configuration ensure long-term stable operation and reduce maintenance costs.

[0025] In summary, this invention realizes the integrated application of the six-character principle of "infiltration, retention, storage, purification, utilization, and drainage" of sponge cities on building facades, achieving multi-functional synergy of rainwater management, climate regulation, carbon sequestration and enhancement, and landscape beautification, forming a three-in-one building facade rainwater treatment system integrating "ecology, function, and landscape". Attached Figure Description

[0026] Figure 1 This schematic diagram illustrates a system block diagram of an ecological interception system for building facades according to an embodiment of the present invention. Figure 2The flowchart schematically illustrates a method for ecological interception of building facades according to an embodiment of the present invention. Detailed Implementation

[0027] The invention will now be discussed with reference to exemplary embodiments. It should be understood that the described embodiments are merely intended to enable those skilled in the art to better understand and thus implement the invention, and are not intended to imply any limitation on the scope of the invention.

[0028] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment".

[0029] Figure 1 This schematic diagram illustrates a system block diagram of an ecological interception system for building facades according to an embodiment of the present invention. Figure 1 As shown, in this embodiment, the building facade ecological interception system includes: The source reduction layer includes: a multi-layered greening hanging pot assembly with a density gradient of sparse upper and dense lower plants arranged along the building facade, with staggered arrangement between each layer of greening hanging pot assembly; each greening hanging pot assembly is filled with a permeable substrate, and a capillary medium composed of coconut coir and vermiculite is embedded between the surface planting soil and the lower infiltration layer (a layer structure laid at the bottom of the hanging pot for infiltration, such as zeolite), forming a three-dimensional infiltration structure of plant roots, permeable substrate and capillary medium; The process control layer includes: a vertical guide channel connected to the infiltration holes at the bottom of the greening hanging pot component, a transverse curved channel connected to the bottom of the vertical guide channel, and an end branch channel connected to both ends of the transverse curved channel; the inner wall of the vertical guide channel is lined with a modified geotextile and a capillary fiber bundle composite lining, and the bottom and side walls of the transverse curved channel are lined with a zeolite and ceramsite capillary composite layer. The end-of-pipe utilization layer includes a water storage and reuse unit that collects and purifies rainwater and an underground capillary infiltration well that allows rainwater to permeate into deeper soil layers, each connected to an end-of-pipe branch.

[0030] In this embodiment, the core of the aforementioned "capillary" is capillary action (capillary phenomenon), which refers to the use of the tiny pores of porous media to achieve slow infiltration, water retention, and purification of rainwater through surface tension. Specifically, its application in this system is divided into three categories: Capillary media: the coconut coir + vermiculite composite layer of the source reduction layer, which utilizes its porous structure to form capillary water channels to achieve uniform infiltration of rainwater, water and fertilizer retention, and at the same time enhance pollutant interception; Capillary fiber bundle composite liner: the inner liner of the vertical guide channel of the process control layer, which slows down the rainwater flow rate and enhances the infiltration and purification effect through the capillary pores of the fiber bundles, while preventing matrix loss; Capillary composite layer / infiltration well: the zeolite + ceramsite layer of the horizontally curved flow channel and the underground capillary infiltration well, which utilize the capillary pores of the filler to achieve deep purification of rainwater, slow infiltration, and groundwater recharge.

[0031] In this embodiment, by arranging multi-layered hanging planter components with a density gradient of sparse upper layers and dense lower layers along the building facade, and with staggered arrangement between each layer of hanging planter components, the rainwater retention time is extended and the runoff velocity is reduced. The sparse upper layer ensures rapid rainwater infiltration and avoids surface runoff; the dense lower layer enhances buffering and interception capacity, slowing down the rate at which rainwater overflows from the edges of the hanging planters. At the same time, the staggered arrangement avoids vertical alignment between the upper and lower hanging planters, allowing rainwater overflowing from the upper hanging planters to first contact the stems and leaves of the plants in the lower hanging planters before falling into the lower hanging planters, thus forming multi-level interception along the vertical path, effectively extending the vertical retention path of rainwater and reducing the runoff volume per unit time.

[0032] In this embodiment, a double-layer infiltration structure of matrix-capillary medium is formed by filling each greening hanging pot component with a permeable matrix and embedding a composite capillary medium of coconut coir and vermiculite between the surface planting soil and the lower infiltration layer. The permeable matrix provides basic rainwater infiltration channels, while the composite capillary medium of coconut coir and vermiculite utilizes its high porosity to achieve lateral diffusion and vertical infiltration of rainwater through capillary suction, thus slowing down the rapid loss of rainwater. On the other hand, the coconut coir and vermiculite materials have an adsorption effect on dissolved pollutants (such as nitrogen and phosphorus) in rainwater, achieving preliminary purification during the infiltration process.

[0033] In this embodiment, a three-dimensional infiltration structure consisting of plant roots, a permeable substrate, and capillary media is formed to achieve synergistic biological-physical water purification. Plant roots grow within the substrate, creating loose pores that maintain its permeability and prevent clogging. The roots directly contact the coconut coir and vermiculite capillary media, forming a three-dimensional infiltration network. As rainwater passes through this structure, it is both mechanically blocked and biologically absorbed by the roots, and physically adsorbed and filtered by the capillary media, thus achieving a synergistic effect of suspended particulate matter retention and dissolved pollutant removal.

[0034] In this embodiment, a three-stage flow path is formed by a vertical guide channel connected to the infiltration holes at the bottom of the hanging planter assembly, a horizontally curved flow channel connected to the bottom of the vertical guide channel, and end branch channels connected to both ends of the horizontally curved flow channel. This structure achieves a step-by-step distribution of rainwater runoff: the vertical guide channel receives rainwater infiltrating from the hanging planter, the horizontally curved flow channel extends the rainwater flow path and connects to the end branch channels, and the curved design of the flow channel increases the rainwater residence time, allowing sufficient time for lateral infiltration during gravity flow, thereby reducing runoff peaks and adapting to the flow regulation needs under different rainfall intensities.

[0035] In this embodiment, a composite liner of modified geotextile and capillary fiber bundles is laid on the inner wall of the vertical diversion channel to achieve the dual functions of diversion and lateral infiltration. The capillary fiber bundles use capillary suction to infiltrate rainwater in the diversion channel into the backfill soil around the channel wall, realizing a dynamic distribution of diversion and infiltration simultaneously, reducing the downstream runoff. The modified geotextile, as a carrier, not only prevents soil particles from entering the diversion channel and causing blockage, but also provides fixed support for the capillary fiber bundles, ensuring the continuous stability of the lateral infiltration function.

[0036] In this embodiment, by laying a zeolite and ceramsite capillary composite layer at the bottom and sidewalls of the laterally curved flow channel, and leveraging the extended residence time due to the channel's curvature, further lateral infiltration of rainwater is achieved through the capillary pores of the zeolite and ceramsite. Zeolite possesses ion exchange capabilities, adsorbing pollutants such as ammonia nitrogen in rainwater; ceramsite provides a stable capillary pore structure, ensuring infiltration efficiency. Simultaneously, this composite layer provides an attachment carrier for microorganisms, enabling the removal of organic pollutants such as COD through microbial degradation during the infiltration process, thus achieving deep purification of rainwater.

[0037] In this embodiment, a rainwater storage and reuse unit that collects and purifies rainwater and an underground capillary infiltration well that permeates rainwater into deep soil are each connected to a terminal diversion branch, achieving a dual-path distribution of rainwater: one part enters the rainwater storage and reuse unit for collection and storage, for subsequent resource utilization; the other part permeates into deep soil through the underground capillary infiltration well, replenishing groundwater. This design achieves both direct water reuse and mitigation of urban groundwater level decline through groundwater replenishment, forming a synergistic effect between use and discharge at the end of the process, avoiding water waste caused by single discharge.

[0038] In this embodiment, the combination of the above three layers achieves a deep integration of ecological interception and engineering diversion: the source reduction layer utilizes the bio-physical effects of plants, substrates, and capillary media to achieve primary purification and flow retention; the process control layer utilizes graded diversion and capillary infiltration to achieve flow regulation and deep purification; and the end-use layer achieves the rational allocation of water resources. The three-layer structure forms a continuous capillary infiltration network through the continuity of the capillary media (coconut coir and vermiculite layers in the hanging basin, fiber bundle layers on the diversion channel walls, and zeolite and ceramsite layers on the flow channel walls). This ensures that rainwater remains in a state of slow flow, infiltration, and purification throughout its flow from the top to the bottom of the building facade, rather than the traditional rapid convergence and discharge. This effectively reduces the peak runoff of rainwater from the building facade and improves rainwater resource utilization and water purification effects.

[0039] Furthermore, according to one embodiment of the present invention, the greening hanging planter assembly is designed to accommodate layered planting, including: The upper layer of tall intercepting plants (growing to the top of the hanging basket, 1.2-1.5m high) uses varieties with spreading stems and fluffy leaves, such as Miscanthus sinensis, Muhlenbergia capillaris, and Pennisetum aurantiacus, paired with trailing plants like String of Pearls and Ivy, with a spacing of 20-30cm between plants; forming an aerial interception barrier. The dense stems and leaves buffer the impact of rainfall, slowing down the rate of rainwater runoff (reducing the runoff velocity by 30%-40%), and trapping suspended particles with a diameter ≥0.5mm. At the same time, the gaps between the stems leave infiltration channels to prevent surface runoff; the trailing vines cover the edges of the hanging basket, further extending the rainwater retention time.

[0040] The middle and low adsorption layer (growing to the middle of the hanging pot, 0.6-1.0m high) is made of shrubs / herbs with thick leaves, abundant hairs, or well-developed root systems, such as Buxus microphylla, Spiraea japonica, and Coreopsis grandiflora, with a plant spacing of 15-20cm. The leaves adsorb trace pollutants (nitrogen, phosphorus, heavy metals) in rainwater, and the roots form loose pores in the substrate to improve the efficiency of rainwater infiltration. Varieties with smooth and dense leaves are avoided to prevent rainwater from flowing quickly along the leaves.

[0041] The lower creeping buffer layer (growing at the bottom of the hanging basket, 0.3-0.5m high) uses creeping, high-coverage ground cover plants such as Sedum lineare, Sedum sarmentosum, and moss, spaced 10-15cm apart; it covers the bottom and edges of the hanging basket, forming a ground buffer zone. The low-growing plant shape slows down the rate at which rainwater overflows from the edges of the hanging basket, and the shallow and dense root system does not clog the seepage holes, while filtering out fine impurities with a particle size ≥0.1mm.

[0042] In this embodiment, varieties with spreading stems and fluffy leaves, such as Miscanthus sinensis, Muhlenbergia capillaris, and Pennisetum aurantiacus, which grow to the top of the hanging pot and reach a height of 1.2-1.5m, are selected and paired with trailing plants such as String of Pearls and Ivy, with a plant spacing of 20-30cm, to form an aerial interception barrier in the building facade space. This invention utilizes the physical blocking effect of dense stems and leaves on rainfall. On the one hand, it buffers the impact of rainfall, converting the kinetic energy of rainwater into potential energy, slowing down the falling speed of rainwater, and reducing the runoff velocity by 30%-40%. On the other hand, the fluffy stem and leaf structure traps suspended particles with a diameter ≥0.5mm, while the gaps between the stems leave infiltration channels, guiding rainwater to infiltrate into the substrate rather than overflowing to the surface, thus preventing surface runoff at the source. The trailing vines of the hanging plants cover the edge of the hanging pot, further extending the retention time of rainwater at the edge of the hanging pot and increasing the opportunity for infiltration.

[0043] In this embodiment, shrubs / herbaceous plants with thick leaves, abundant hairs, or well-developed root systems, such as Buxus microphylla, Spiraea japonica, and Coreopsis grandiflora, which grow to the middle of the hanging basket and reach a height of 0.6-1.0m, are selected. The spacing between plants is controlled at 15-20cm to achieve deep purification and efficient infiltration of rainwater. This invention utilizes the morphological characteristics of thick, hairy leaves to adsorb trace pollutants (nitrogen, phosphorus, heavy metals) in rainwater through the leaf surface, prolonging the contact time between rainwater and plants. Simultaneously, the root system grows in the substrate, forming loose pores that maintain the substrate's permeability and aeration, while also promoting microbial activity through root secretions, thus improving rainwater infiltration efficiency. By avoiding varieties with smooth, dense leaves, rapid runoff of rainwater along the leaf surface is prevented, ensuring sufficient contact between rainwater and the plant and substrate.

[0044] In this embodiment, creeping, high-coverage ground cover plants such as Sedum lineare, Sedum sarmentosum, and mosses, growing at the bottom of the hanging basin and reaching a height of 0.3-0.5m, are selected. The plants are spaced 10-15cm apart, covering the bottom and edges of the hanging basin to form a ground buffer zone. This invention utilizes the low-growing plant type to slow down the rate at which rainwater overflows from the edges of the hanging basin. A shallow and dense root network filters rainwater at the end, trapping fine impurities with a particle size ≥0.1mm. Simultaneously, the shallow root depth does not clog the bottom infiltration holes, ensuring smooth infiltration. The dense coverage of the lower layer of plants reduces substrate exposure, lowers water evaporation, maintains surface humidity, and provides a stable rhizosphere environment for the upper and middle layers of plants.

[0045] In this embodiment, a functional gradient of interception, adsorption, and buffering is formed through the synergistic vertical configuration of upper, middle, and lower layers of plants. The upper layer reduces kinetic energy and traps large particles, the middle layer adsorbs dissolved pollutants and promotes infiltration, and the lower layer filters fine impurities and ensures the quality of the effluent. This three-stage treatment achieves step-by-step purification of rainwater. Simultaneously, the plant spacing gradients of the three levels (20-30cm, 15-20cm, and 10-15cm) create a sparse upper and dense lower spatial layout, ensuring rapid infiltration from the upper layer while delaying overflow through dense buffering in the lower layer, achieving an optimized balance between rainwater retention time and treatment efficiency within a single basin. The differences in root depth among the three levels of plants (tall plants with deep roots, medium-short plants with medium roots, and creeping plants with shallow roots) form a three-dimensional porous network in the substrate, working synergistically with the permeable substrate and capillary media to construct a three-dimensional infiltration structure, enhancing overall infiltration and purification efficiency.

[0046] Furthermore, according to one embodiment of the present invention, a semi-blank layer is provided between every 3-4 layers of greening hanging pot components. The semi-blank layer is planted only with ground cover plants and has a drainage gap reserved. The drainage gap guides part of the rainwater to the vertical drainage channel.

[0047] In this embodiment, in a continuously densely planted multi-layered hanging planter assembly, the dense distribution of plant roots in the substrate significantly increases infiltration resistance as the number of layers increases. This causes rainwater to remain in the upper hanging plants for too long, resulting in water accumulation or even overflow. By setting a semi-blank layer between every 3-4 layers of hanging planters, utilizing its structural features of planting only a small number of ground cover plants and reserving drainage gaps, a low-resistance channel is provided for vertical rainwater flow. This design effectively balances the problem of accumulated infiltration resistance caused by multiple layers of plant stacking, ensuring that while maintaining sufficient plant interception area, the overall drainage efficiency of the system is maintained, and preventing excessive concentration and retention of rainwater at the top of the facade.

[0048] Under heavy rainfall conditions, when the rainfall per unit time exceeds the permeability of the plant layer and substrate, the drainage gaps in the semi-blank layer act as diversion points, directly guiding the excess rainwater to the vertical drainage channels instead of forcibly passing through the substrate layer of the upper hanging basins. This scheme achieves tiered overflow management of rainwater: priority is given to permeating and purifying through the plant layer, while the excess is quickly discharged through the drainage gaps. This protects the upper plants from root hypoxia caused by prolonged waterlogging and reduces the peak flow of rainwater entering the lower hanging basins by diverting the water in advance, preventing overall system overload during heavy rainfall.

[0049] The semi-blank layer, planted only with ground cover plants, exhibits significantly reduced root density and depth, minimizing the occupation of substrate pores and maintaining the high porosity of this layer. Vertically, this periodically low-density layer acts as a root barrier, preventing excessive root penetration into the lower layers and thus avoiding blockage of the underlying infiltration pores. Simultaneously, pre-reserved drainage gaps prevent dense root entanglement in specific locations, ensuring unobstructed vertical drainage channels during long-term operation and extending system maintenance cycles.

[0050] By using semi-blank layers spaced 3-4 times apart, the continuous plant interception section is divided into multiple treatment units. Each unit achieves full infiltration and purification, and the units are hydraulically connected through flow-guiding gaps. This segmented structure optimizes the vertical flow path of rainwater on the building facade: in sections with high plant density, lateral infiltration and matrix filtration are the main methods, while vertical guidance is the main method in the semi-blank layers, forming a pulsed flow pattern of infiltration, guidance, and re-infiltration. Compared with the single mode of continuous dense planting, this improves the contact efficiency between rainwater and the matrix and microorganisms, while ensuring drainage safety.

[0051] Furthermore, according to one embodiment of the present invention, the permeable matrix is ​​composed of humus, perlite, and coarse sand in a volume ratio of 3:2:1.

[0052] In this embodiment, humus provides organic matter and water retention, perlite increases porosity and aeration, and coarse sand ensures smooth drainage. The 3:2:1 ratio allows the three components to synergistically form a suitable pore structure: the highest proportion of humus ensures substrate fertility and water retention, perlite provides stable pore space, and a moderate amount of coarse sand prevents excessive drainage. This ratio achieves a balance between rapid rainwater infiltration and moderate retention, preventing waterlogging while ensuring adequate water supply to plant roots. At this ratio, the binding properties of humus are moderately diluted by perlite and coarse sand, forming a loose and non-compacting substrate structure. The lightweight nature of perlite reduces the load on the hanging basket, while the particle support of coarse sand maintains long-term pore stability, providing a permeable rhizosphere environment for plant root growth, while also ensuring space for root exudates and microbial activity, promoting the biodegradation of pollutants.

[0053] Furthermore, according to one embodiment of the present invention, the particle size of the coconut coir and vermiculite composite capillary medium is 0.5-2 mm, the rate is 60%-70%, and the thickness is 5-8 cm.

[0054] In this embodiment, the coconut coir and vermiculite particles within the aforementioned particle size range form a continuous capillary network. A lower particle size limit of 0.5 mm ensures the formation of effective capillaries between particles, generating sufficient capillary force to drive the lateral diffusion of rainwater; an upper particle size limit of 2 mm prevents excessively coarse particles from weakening capillary action. This particle size distribution within this range gives the composite medium both capillary force and permeability, slowing down rapid rainwater runoff without completely blocking infiltration.

[0055] A high porosity of 60%-70% provides ample water storage space, enabling the composite medium to temporarily retain some rainwater and extend the hydraulic retention time. Simultaneously, the retained 30%-40% solid skeleton ensures structural stability and provides necessary oxygen channels for root respiration and microbial activity. This porosity range achieves a balance between water storage and aeration requirements, preventing either excessive moisture leading to oxygen deficiency or excessive dryness causing failure.

[0056] A thickness of 5-8 cm provides sufficient vertical infiltration path length for rainwater. The lower limit of 5 cm ensures the formation of an effective capillary layer, enabling lateral diffusion; the upper limit of 8 cm avoids excessive thickness that could lead to excessive infiltration resistance or increased load on the hanging basin. This thickness range allows rainwater to fully contact the surface of the capillary medium for adsorption and purification while maintaining a reasonable infiltration rate, thus synergizing with the upper and lower layers.

[0057] The organic properties of coconut coir combined with the layered mineral structure of vermiculite work synergistically to improve the removal efficiency of dissolved pollutants. On the one hand, the fiber network of coconut coir fixes the particle structure and maintains pore stability; on the other hand, the ion exchange capacity of vermiculite adsorbs dissolved pollutants such as nitrogen and phosphorus in rainwater, while coconut coir provides attachment sites for microorganisms to promote biodegradation. The two work together to improve the removal efficiency of dissolved pollutants.

[0058] Furthermore, according to one embodiment of the present invention, the vertical guide channel is designed with a structure that is wider at the top and narrower at the bottom, with an upper opening width of 20cm and a lower opening width of 10cm. A first diversion port is provided on it, and one first diversion port is provided for every three layers of greening hanging pot components. A capillary water-blocking strip with a height of 3cm is provided at the first diversion port, and the capillary water-blocking strip has capillary fibers inside.

[0059] In this embodiment, the gradually tapering cross-section, with an upper opening width of 20cm and a lower opening width of 10cm, creates a funnel effect. The wide upper space accommodates rainwater collection from the multi-layered hanging basin assembly, reducing the flow velocity at a single point and minimizing erosion; the narrower lower cross-section accelerates rainwater flow, preventing siltation caused by slow-velocity sedimentation. This structure adapts to the vertical space of building facades, receiving large areas of incoming water at the top and rapidly guiding the flow at the bottom, maintaining stable hydraulic conditions within the channel.

[0060] One primary drainage outlet is installed for every three layers of hanging planters, dividing the continuous vertical flow channel into multiple control units. This design enables tiered rainwater collection: when the infiltration rate of the upper hanging planters is low, rainwater flows down the channel wall; when the flow rate increases to the elevation of the drainage outlet, some rainwater overflows from the primary drainage outlet, preventing all rainwater from rushing downstream and causing overload. The density of the three-layer spacing balances the uniformity of water collection with structural complexity, ensuring timely drainage of rainwater from each layer of hanging planters while avoiding structural weakening caused by excessively dense drainage outlets.

[0061] A 3cm high capillary baffle strip is installed at the first diversion inlet. Utilizing the suction of built-in capillary fibers, it retains rainwater about to overflow. The capillary fibers absorb some of the rainwater and guide it to the surrounding soil, intercepting it before overflow and reducing direct discharge. Simultaneously, the 3cm height forms a micro-weir, slowing the overflow velocity and increasing the residence time of rainwater within the channel, promoting lateral infiltration. This design combines engineering drainage with capillary infiltration, giving the first diversion inlet both overflow and infiltration functions.

[0062] The upper, narrower lower channel, the tiered diversion outlets, and the capillary baffles work together to form a dynamic control mechanism for collection, retention, diversion, and lateral infiltration: during light rain, rainwater is mainly released slowly through retention by the capillary baffles and lateral infiltration; during moderate rain, the diversion outlets overflow in stages, and the capillary baffles reduce the peak flow; during heavy rain, the narrow lower outlet quickly drains excess rainwater, preventing system water accumulation. This structure requires no mechanical adjustment components, relying on hydraulic characteristics and capillary action to achieve adaptive flow distribution, adapting to changes in operating conditions with different rainfall intensities.

[0063] In this embodiment, the materials of the vertical guide channel include: the channel body material: conventionally using corrosion-resistant and aging-resistant plastic materials such as UPVC (rigid polyvinyl chloride) and HDPE (high-density polyethylene), or stainless steel, to suit the outdoor environment of building facades; the inner lining composite layer: the inner wall of the vertical guide channel must be laid with a modified geotextile and capillary fiber bundle composite lining layer, which is used to enhance infiltration, slow down the flow rate, and prevent clogging.

[0064] Furthermore, according to one embodiment of the present invention, a flow regulating valve and a capillary infiltration disc are provided at the connection between the bottom of the vertical guide channel and the transverse curved flow channel; the flow regulating valve is dynamically adjusted according to the rainwater flow rate, opening 30% during heavy rain (reducing the amount of rainwater entering the flow channel), and opening 70% during light rain (increasing the rainwater collection rate). The capillary infiltration disc is made of porous ceramic material. Some rainwater is discharged through the horizontally curved channel, while some rainwater infiltrates into the shallow soil through the capillary infiltration disc, with a cumulative runoff reduction rate of 50%-60%.

[0065] In this embodiment, the flow regulating valve dynamically adjusts its opening based on the rainwater flow rate: during heavy rain, it opens to 30%, limiting the amount of rainwater entering the transversely curved flow channel and allowing most of the rainwater to be dispersed and treated through other paths (such as lateral infiltration through vertical guide channels and retention by capillary baffles), thus avoiding channel overload; during light rain, it opens to 70%, improving the rainwater collection rate and ensuring that scarce rainwater resources are preferentially used in the reuse system. This design requires no external power, relying on hydraulic characteristics or a simple float / gravity structure to achieve automatic adjustment, adapting to the needs of different rainfall intensities and balancing the conflict between drainage safety and resource recovery.

[0066] The capillary infiltration disc is made of porous ceramic material, utilizing the capillary suction of the ceramic pores to infiltrate some rainwater into the shallow soil. This process reduces the final discharge or collection runoff, achieving a cumulative runoff reduction rate of 50%-60%; on the other hand, it replenishes the soil with purified rainwater, conserving groundwater and avoiding water resource loss caused by traditional rapid drainage methods. The chemical stability of the porous ceramic ensures long-term operation without clogging, and the material strength guarantees structural durability.

[0067] The flow regulating valve and the capillary infiltration disc are spatially adjacent, forming a combined treatment node for regulation and infiltration. The regulating valve controls the total flow rate entering the flow channel, while the capillary infiltration disc diverts a portion of the rainwater downstream of the valve. Together, they achieve a three-stage distribution of rainwater: overflow before the regulating valve (returning to the vertical guide channel for side infiltration), flow channel downstream of the regulating valve (entering the water storage and reuse unit), and side infiltration through the infiltration disc (replenishing the soil). This staged distribution extends the rainwater treatment path, increases the contact time with the purification medium, and improves the water purification effect.

[0068] During heavy rain, a 30% valve opening allows 70% of rainwater to be intercepted by upstream lateral infiltration and the infiltration plate. During light rain, a 70% valve opening allows 30% of rainwater to be infiltrated by the infiltration plate. By combining the weighted effects of different rainfall frequencies, a cumulative runoff reduction rate of 50%-60% is achieved. This quantitative target is achieved through the matching design of structural parameters (valve opening, infiltration plate area) and material parameters (ceramic porosity), providing an engineering implementation path for the runoff control indicators of sponge cities.

[0069] Furthermore, according to one embodiment of the present invention, the capillary bundles in the modified geotextile and capillary bundle composite lining have a diameter of 0.1-0.3 mm and a length of 10-15 cm.

[0070] Furthermore, according to one embodiment of the present invention, the particle size of the zeolite and ceramsite capillary composite layer is 2-5 mm, the capillary porosity accounts for 40%, and the thickness is 10-15 cm.

[0071] Furthermore, according to one embodiment of the present invention, the underground capillary infiltration well has a diameter of 50 cm and a depth of 1.5-2 m, and is filled with gravel and biochar capillary media.

[0072] Furthermore, to achieve the above objectives, the present invention also provides a method for ecological interception of rainwater on building facades, such as... Figure 2 As shown, it includes: Source interception: Rainwater is intercepted and initially purified in layers by arranging a multi-level plant interception system with a density gradient of sparse at the top and dense at the bottom along the building facade. Each level of the plant interception system includes at least one layer of green hanging pot components planted with plants. After being intercepted by the plants, the rainwater diffuses laterally and penetrates vertically through a composite capillary medium of coconut coir and vermiculite. Process control: Rainwater intercepted at the source enters the vertical guide channel. Part of it infiltrates the backfill soil around the channel wall through the modified geotextile and capillary fiber bundle composite liner, while the other part flows downward along the vertical guide channel. It then enters the transverse curved channel and infiltrates into the surrounding soil through the zeolite and ceramsite capillary composite layer, while the residual pollutants are degraded by the microorganisms in the pores. End-of-pipe utilization: Rainwater that has undergone process control is diverted through end-of-pipe branches, with one part entering the water storage and reuse unit and the other part entering underground capillary infiltration wells to replenish groundwater.

[0073] The above-described building facade rainwater ecological interception method according to the present invention is implemented by the above-described building facade ecological interception system. The specific system content is as described above and will not be repeated here.

[0074] According to the above-described scheme of the present invention, the present invention achieves the reduction of rainwater runoff velocity and cumulative runoff volume through the synergistic effect of the multi-layered greening hanging pot assembly with sparse upper and dense lower layers and the three-level flow guiding structure within the greening hanging pot assembly; the purified rainwater achieves a higher reuse rate through the water storage and reuse unit, and is used for greening irrigation, greenway flushing, etc. At the same time, groundwater is replenished through underground capillary infiltration wells, forming a dual-path resource allocation of use and infiltration, which alleviates the problems of urban water shortage and groundwater level decline.

[0075] Through a three-dimensional infiltration structure of plant roots, substrate and capillary media, lateral infiltration of modified geotextile and capillary fiber bundle composite lining, microbial degradation of zeolite and ceramsite capillary composite layer, and biochar adsorption in underground infiltration wells, rainwater is purified in multiple stages. The purification process relies on plant physiological activities and microbial action to form an ecological self-circulation and reduce dependence on chemical treatment.

[0076] By using the shading and cooling effect of the upper-layer tall plants, the transpiration and humidification effect of the middle-layer plants, and the water retention and evaporation reduction effect of the lower-layer plants, the building facade temperature can be seasonally adaptively adjusted: reducing the exterior wall temperature in summer, ensuring light penetration in winter, maintaining the facade humidity balance throughout the year, improving the building thermal environment and mitigating the urban heat island effect.

[0077] By utilizing the light gradient of upper, middle, and lower layers of plants and coordinating photosynthetic carbon sequestration, the overall carbon sequestration capacity of the system is enhanced; at the same time, relying on the seasonal changes of plants to form a rich facade landscape, the unity of ecological function and visual aesthetics is achieved, contributing to the carbon balance and ecological quality improvement of sponge cities.

[0078] The system achieves automatic regulation under different rainfall intensities by utilizing the self-driving characteristics of capillary permeation, the hydraulic self-adaptation of the flow regulating valve, and the working condition adaptation of the graded flow guiding structure; the modular structure and durable material configuration ensure long-term stable operation and reduce maintenance costs.

[0079] In summary, this invention realizes the integrated application of the six-character principle of "infiltration, retention, storage, purification, utilization, and drainage" of sponge cities on building facades, achieving multi-functional synergy of rainwater management, climate regulation, carbon sequestration and enhancement, and landscape beautification, forming a three-in-one building facade rainwater treatment system integrating "ecology, function, and landscape".

[0080] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

[0081] It should be understood that the sequence number of each step in the invention and its embodiments does not absolutely imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Claims

1. An ecological interception system for building facades, characterized in that, include: The source reduction layer includes: a multi-layered greening hanging pot assembly with a density gradient of sparse upper and dense lower plants arranged along the building facade, with each layer of greening hanging pot assembly arranged in a staggered manner; each greening hanging pot assembly is filled with a permeable substrate, and a capillary medium composed of coconut coir and vermiculite is embedded between the surface planting soil and the lower infiltration layer, forming a three-dimensional infiltration structure of plant roots, permeable substrate and capillary medium; The process control layer includes: a vertical guide channel connected to the infiltration holes at the bottom of the greening hanging pot assembly, a transverse curved flow channel connected to the bottom of the vertical guide channel, and end branch channels connected to both ends of the transverse curved flow channel; the inner wall of the vertical guide channel is lined with a modified geotextile and capillary fiber bundle composite lining, and the bottom and side walls of the transverse curved flow channel are lined with a zeolite and ceramsite capillary composite layer. The end-of-pipe utilization layer includes a water storage and reuse unit for collecting and purifying rainwater and an underground capillary infiltration well for permeating rainwater into deeper soil, each connected to one of the aforementioned end-of-pipe branch lines.

2. The building facade ecological interception system according to claim 1, characterized in that, The greening hanging planter assembly is designed for tiered planting, including: The upper tall-stemmed interception layer includes one or more of the following: Miscanthus sinensis, Muhly grass, and Amorphophallus aurantiacus, combined with string plants and trailing ivy, with a plant spacing of 20-30cm. The middle and low adsorption layer includes one or more of the following: Buxus microphylla, Spiraea japonica, and Coreopsis grandiflora, with a plant spacing of 15-20cm. The lower creeping buffer layer includes one or more of Sedum lineare, Sedum sarmentosum, and mosses, with a plant spacing of 10-15cm.

3. The building facade ecological interception system according to claim 1, characterized in that, A semi-blank layer is set between every 3-4 layers of greening hanging pot components. The semi-blank layer is planted only with ground cover plants and has a drainage gap. The drainage gap guides part of the rainwater to the vertical drainage channel.

4. The building facade ecological interception system according to claim 1, characterized in that, The permeable substrate is composed of humus, perlite, and coarse sand in a volume ratio of 3:2:

1.

5. The building facade ecological interception system according to claim 1, characterized in that, The composite capillary medium of coconut coir and vermiculite has a particle size of 0.5-2 mm, a porosity of 60%-70%, and a thickness of 5-8 cm.

6. The building facade ecological interception system according to claim 1, characterized in that, The vertical guide channel is designed with a structure that is wider at the top and narrower at the bottom. The top opening is 20cm wide and the bottom opening is 10cm wide. It is equipped with a first diversion port, and one first diversion port is set for every three layers of greening hanging pot components. A capillary water-blocking strip with a height of 3cm is set at the first diversion port. The capillary water-blocking strip has built-in capillary fibers.

7. The building facade ecological interception system according to claim 1, characterized in that, A flow regulating valve and a capillary permeation plate are provided at the connection between the bottom of the vertical guide channel and the horizontal curved flow channel. The capillary infiltration plate is made of porous ceramic material. Some rainwater is discharged through the horizontally curved channel, and some rainwater infiltrates into the shallow soil underground through the capillary infiltration plate.

8. The building facade ecological interception system according to claim 1, characterized in that, The capillary bundles in the modified geotextile and capillary bundle composite lining have a diameter of 0.1-0.3 mm and a length of 10-15 cm.

9. The building facade ecological interception system according to claim 1, characterized in that, The zeolite and ceramsite capillary composite layer has a particle size of 2-5 mm, a capillary porosity of 40%, and a thickness of 10-15 cm.

10. The building facade ecological interception system according to claim 1, characterized in that, The underground capillary infiltration well has a diameter of 50 cm and a depth of 1.5-2 m, and is filled with gravel and biochar capillary media.

11. A method for ecological interception of rainwater on building facades, characterized in that, include: Source interception: Rainwater is intercepted and initially purified by multi-layered greening hanging pot components arranged along the building facade with a density gradient of sparse at the top and dense at the bottom. After being intercepted by the plants, the rainwater diffuses laterally and penetrates vertically through the composite capillary medium of coconut coir and vermiculite. Process control: Rainwater intercepted at the source enters the vertical guide channel. Part of it infiltrates the backfill soil around the channel wall through the modified geotextile and capillary fiber bundle composite liner, while the other part flows downward along the vertical guide channel. It then enters the transverse curved channel and infiltrates into the surrounding soil through the zeolite and ceramsite capillary composite layer, while the residual pollutants are degraded by the microorganisms in the pores. End-of-pipe utilization: Rainwater that has undergone process control is diverted through end-of-pipe branches, with one part entering the water storage and reuse unit and the other part entering underground capillary infiltration wells to replenish groundwater.

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