Urine collection train toilet
At present, passenger train toilets are developing from direct row to toilet collection. The forms of toilets can be roughly divided into circulating type and vacuum type. Recycle can save water by adding chemicals to the dirt and washing the stool circularly with the dirt. However, the circulating toilet has a strong odor in use, and because the application of chemicals is easy to cause secondary pollution, it brings trouble to the later treatment of feces. The vacuum toilet has the advantages of water saving (0.25~0.5L of water for each flush), sanitation and no odor (there is a special valve to prevent the odor of sewer pipes from escaping into the toilet), but its valve parts and pipe diameters are small, which makes it difficult to solve the blockage problem caused by large pollutants such as newspapers and sanitary napkins. Aiming at these problems, a new type of pneumatic push-pull toilet was developed.
Pneumatic push-pull toilet belongs to water-saving toilet. Its basic working principle is to install a small coupler between the toilet and the toilet box, and the piston in the coupler is driven by the power source (compressed air) on the bus. When the piston is pulled back (dotted line indicates its position), dirt enters the coupler; When the piston moves forward, dirt is pushed into the toilet box. Water is pressurized by compressed air, and the toilet is flushed with pressurized water to save water.
Working principle of pneumatic push-pull toilet
Pneumatic push-pull toilet adopts pump-less pressurizing flushing device, which pressurizes water through compressed air on the bus, saving water pump, saving electricity and reducing failure rate. The flushing process is automatically divided into two times, the first time is the pressurized flushing water, and the second time is used to close the sewage outlet of the toilet.
Data such as water consumption, gas consumption and flushing air pressure are obtained through experiments, as shown in Table 1. As can be seen from the table 1, the total water consumption is ≤800mL, and the gas consumption is ≤5L. The effect of flushing toilets is related to the flushing volume and its pressure. When the pressure of compressed air is relatively small, the gas consumption is small, the amount of water for washing at one time is small, and the pressure of washing water is also small, so the washing effect is poor. When the added compressed air pressure is too high, the gas consumption will increase, and the flushing water pressure will also increase if the primary flushing water volume is too large. Although the washing effect is good, because the washing water pressure is too high, washing water and dirt are easy to splash on passengers. Therefore, in order to achieve better flushing effect, a certain amount of water and pressure are needed, and the pressure of compressed air must be correctly selected.
In terms of the influence of toilet air on train braking, the air consumption of closed slab train toilet is 13.8L/ time, and that of jet vacuum train toilet is >: 25L/ time. In contrast, the push-pull train toilet greatly reduces the gas consumption and will not affect the normal operation of the train.
Pneumatic push-pull toilet uses compressed air source and water source on the bus, which consumes less gas and water. The flushing time is short (about 3.5s/ time), and the interval between each flushing cycle is short (
Ground manure collection and transportation system
The fecal ground collection and transportation system can be divided into two categories. One is vacuum moving, that is, the passenger trains staying on the collection and transportation line are sucked by vacuum dung suction vehicles one by one, and the dirt is transported to sewage treatment facilities. Vacuum dung suction truck can be modified from battery truck or fuel truck. Generally, it consists of car body, dirt tank, vacuum pump, vacuum gauge, liquid level gauge, quick connector, drain valve and pipeline. In addition, the system needs to be equipped with dung suction vehicle, garage, duty room and communication facilities. The other is fixed, that is, the sewage tank in the toilet of passenger train is sucked and transported to the sewage treatment facility by using the fixed pipeline system and suction equipment on the ground. According to the characteristics of the equipment, the facility can be divided into two types. One is vacuum collection and transportation system, which is mainly composed of vacuum gun, vacuum transportation pipeline and vacuum station. Vacuum station generally consists of vacuum tank, vacuum pump, sewage pump and automatic control cabinet. Usually, the volume of the vacuum tank is designed according to 1.2 times of the maximum fecal suction. In order to reduce the volume of vacuum tank, three tanks can be used, that is, three tanks are connected in series, and each stage is controlled by a valve. The other is a sewage pump unloading and collecting system consisting of a rotary piston pump and a receiving pipeline.
Waste resource treatment
If the train manure is directly discharged into the urban sewage pipeline, it will pollute the environment or increase the load of the local sewage treatment plant. Pneumatic push-pull toilet uses less water and has high fecal concentration, so it has the value of resource treatment. Feces can be treated harmlessly first, and then recycled.
There are two kinds of commonly used fecal recycling processes: anaerobic process and high temperature oxygen consumption process. Anaerobic method refers to the discharge of feces into biogas digesters, which are decomposed by anaerobic microorganisms under anoxic conditions, thus promoting the liquefaction and gasification of organic matter and generating biogas for fuel, power generation and heating. The manure residue after anaerobic digestion is an excellent organic fertilizer rich in humus, which has higher fertilizer efficiency than the usual farmyard manure. High-temperature oxygen consumption method is to dehydrate feces with a dehydrator, add deodorized fermented biological strains and adjustment materials, mix them with a blender, and carry out dynamic strong ventilation fermentation in the first-class fermentation warehouse and the second-class fermentation warehouse for 10 ~ 20 days, and kill pathogens at high temperature to obtain high-quality and efficient microbial fertilizer.
Deodorization, dehydration, culture and fermentation to produce deodorized microbial agents are the key technologies for the resource utilization of feces. The specific resistance of the suspension simply and intuitively describes its dehydration performance. The specific resistance of pneumatic push-pull toilet feces is about 4.7× 10 14m/kg (activated sludge is 2.7×10/3m/kg). After adding 1% quicklime for coagulation, the specific resistance of feces can be reduced to 4. 1× 65438. On this basis, develop or use the corresponding dehydration machinery to dehydrate the feces, laying the foundation for the recycling of feces. Then, through the excrement recycling process, the excrement can be recycled.
conclusion
(1) Pneumatic push-pull toilet is environmentally friendly and water-saving.
(2) The vacuum collection and transportation system is suitable for the collection and transportation of passenger train feces.
(3) The concentration of feces in pneumatic push-pull toilet is high. Adding CaO at the weight ratio of 1% can effectively reduce the specific resistance of feces, improve its dehydration performance, and make it have the value of further resource utilization.