Waste

WASTE, residues that have become unnecessary or harmful after the use of any substances or objects in the economic or industrial life of man. Waste also includes excrement, urine, carcasses, and all kinds of refuse. The concept of waste is not firmly established. It changes depending on the state of technology, economic factors, and the cultural views of the population. At the present time, in all countries, including the USSR, there is a clear tendency to narrow the quantity of substances classified as waste and a desire to view most waste merely as raw material for various methods of utilization. The removal and neutralization of waste is a responsible task for the bodies of sanitary supervision and municipal services, which finds its resolution in a system of measures called the cleaning of populated areas (see). At the current level of culture, especially in large cities, waste presents an enormous variety, which makes its classification extremely difficult. In specialized literature, there are only isolated attempts to provide a more or less complete classification of waste, based on economic and sanitary aspects in their evaluation. American authors R. Hering and S. Greeley provide the following classification, which is based on their origin (see table). For practical purposes, one can propose the following classification, in which various wastes are grouped according to the commonality of sanitary-technical measures aimed at their removal and neutralization. Waste of populated areas. 1. Liquid waste: a) sewage: feces and urine; b) slop water: dirty water from cooking food, washing the body and floors, laundry, etc.; c) wastewater removed by sewerage: domestic wastewater, industrial wastewater. 2. Solid waste: a) household or economic waste, which includes kitchen waste, wood, paper, textiles, bones, coal, metal, stones, glass, rubber, room sweepings; b) waste from industry, trade, public catering establishments, and institutions; their composition is extremely diverse and depends on the type of establishment; this includes metal, paper, leather, textiles, residues of chemical production, wood, food waste, etc.; c) street sweepings, snow, sediment from storm drains. 3. Waste of animal origin: a) slaughterhouse waste: whole carcasses and parts thereof rejected by veterinary-sanitary supervision (confiscated items), hides from infected animals, paunch contents (contents of the first three compartments of the stomach of ruminants: rumen, reticulum, omasum), fetal calves, piglets, and other animals, parts of animals not intended for food and not processed for other needs (genitals, trachea, pieces of fat and meat, etc.); b) carcasses of dead animals; c) food waste confiscated by sanitary supervision; d) manure. The waste listed in section 1 is removed either by transport in sewage containers (see Sanitation) or by sewerage (see). The waste listed in section 2 is removed by the collection system; however, their subsequent fate is sharply different from liquid waste from non-sewered properties (see Refuse, Incineration, Cleaning of populated areas). Finally, the disposal of waste from the 3rd section takes place at specific facilities: utilization plants, in burial grounds (see Cemetery, animal cemeteries), or in the process of utilization in agriculture (see Manure). In cities and industrial centers, one has to deal with all the above-mentioned types of waste. In agricultural-type settlements, sewage and slop water, as well as animal manure, are of the greatest importance, the removal and neutralization of which must be closely linked to their use in agriculture as fertilizer (see Sanitation, Closets, Manure). The chemical composition of waste, its physical properties, and quantity are extremely diverse. Liquid waste from non-sewered properties consists of sewage (feces and urine), usually collected in cesspools, and slop water, collected in slop basins. The quantity of both varies significantly depending on local conditions: the cultural level of the population's life and the technical state of the waste receptacles. The quantity of feces and urine ranges from 1150 g (Dobroslavin) to 1400 g (Pettenkofer) per day per person—about 0.5 m³ per year (assuming the weight of sewage is equal to the weight of water). The quantity of slop water depends on water consumption and can be assumed for households without running water and sewerage to be from 15 to 25 liters per person per day. However, these theoretical norms are many times greater than the quantity of liquid waste that is usually removed by the collection system from non-sewered properties. Khlopin believes that no more than 10% of dirty water is available for removal. According to data from the city of Moscow, only 6% of the theoretical accumulation is removed; the rest is absorbed by the soil due to the poor construction of slop basins and cesspools. Based on empirical observations, an accumulation of 0.6 m³ per person per year (one 50-bucket barrel) is usually assumed when calculating sanitation systems. The quantity of wastewater is subject to precise calculations when installing sewerage (see). The quantity of refuse can be assumed for large cities of the USSR to be 0.5 m³ per person per year (Moscow, Leningrad, Kharkov); however, this quantity is subject to large fluctuations and must be established on the basis of systematic research in each individual case. Street sweepings, according to Moscow data, amount to only 0.015 m³ per 1 m² of pavement per year. Its quantity depends on the method of paving, the intensity of traffic, the climate, and the method of cleaning. The quantity of industrial waste, as well as its composition, cannot be established in advance and is subject to study in each individual case. From the 3rd group of the presented scheme, paunch contents are of significant interest from a sanitary point of view, both in terms of their quantity (up to 12% of the live weight of cattle) and the difficulty of their processing and neutralization. Paunch contents consist mainly of cellulose, which is extremely difficult to decompose, as a result of which it remains preserved for up to 10 years when buried in the ground. Attempts to utilize paunch contents for animal feed or fuel are not yet economically profitable. Regarding compost, thanks to the action of anaerobic processes, it is processed into good fertilizer in 1.5–2 years. The accumulation of waste causes significant harm to human health. Products of the decomposition of organic waste substances pollute the soil, air, and water. Waste can contain poisonous substances (industrial wastewater and refuse): poisonous paints, lead, arsenic, chlorine, and other substances. Waste dust irritates the human respiratory tract, mucous membranes, and skin. Waste serves as a medium where pathogenic microbes retain their viability for a long time and sometimes multiply; waste also contains helminth eggs. Finally, waste (manure, refuse, feces) is a place for fly breeding and contributes to the reproduction of rats (food waste, refuse). Below is a summary table by Dr. Levinson: Microbe Name: Epidemiological role of waste in the spread of infection. Koch's tubercle bacillus: Found in street refuse, in dust, and in sewage. Eberth-Gaffky typhoid bacillus: Found in sewage, in solid waste, in the silt of water bodies, on vegetables from irrigation fields, etc. Bacteria of the paratyphoid and Gaertner group: Frequently found in the excrement of sick and healthy (bacillus carriers) people and animals. Widely distributed in the external environment, where they can lead a saprophytic life. Shiga-Kruse dysentery bacillus: Excreted in huge quantities in the excrement of the sick; excretion can continue for several weeks after recovery. Cholera vibrio: Excreted in the excrement of the sick and bacillus carriers. Water bodies, soil, and solid waste can be contaminated by excrement. Pyogenic microbes: staphylococcus, streptococcus, and blue-green pus bacillus: Found in all kinds of waste and in dust. Tetanus bacillus and its spores: Almost constantly found in the surface layers of the soil of fields, courtyards, and in street refuse. The source of infection is the excrement of horses and cattle, which almost as a rule contain tetanus bacillus spores. Anthrax bacillus and its spores: Soil and water are contaminated by feces, urine, and other discharges of sick animals. Favorable conditions for spore formation are created in waste.

Beinart recommends composting rumen contents mixed with [missing text] as the cheapest and most effective processing method. In view of the danger that waste represents from a sanitary standpoint, concern for its timely removal and neutralization is one of the most important functions of municipal services and sanitary supervision. The best method for removing waste is its daily collection in specially adapted vehicles: automobiles or horse-drawn carts (see Refuse, Cleaning of populated areas). Neutralization itself takes place in special facilities depending on the type of waste. For solid waste—municipal refuse—the most radical method is burning it in special destructors (see Refuse incineration). Another most common method of neutralization is the soil method on special plots. In this case, the refuse is spread in a thin layer up to 1.0 m and undergoes mineralization under the influence of the natural forces of nature. Studies by the Erisman Moscow Sanitary Institute have shown that at least 6 years are required for the mineralization of a 1.0 m layer of refuse. Plowing the plot and sowing it with grass accelerate mineralization. Recently, the use of refuse in agriculture for fertilizer, and mainly as a source of heat in hotbeds, has become increasingly widespread. This method deserves the greatest attention, since it allows populated areas to eliminate unsanitary dumps with the greatest benefit. Finally, in Italy, Switzerland, and America, the method of placing refuse in special chambers (Beccari chambers, Biaggiano-Picho septic towers) has gained some development, where it is fermented over a certain period of time, turning into excellent fertilizer. Liquid waste is neutralized either on irrigation fields and at biological facilities (see Wastewater, Biological method of wastewater treatment) or, in the case of removal by collection in cesspool barrels, on sewage fields (see Sanitation). The neutralization of night soil can also occur in the process of using it in agriculture, which takes place either directly by fertilizing fields and plowing in the night soil or by mixing night soil with peat (preparation of peat-fecal compost). The utilization of waste (see diagram) is extremely diverse, just as the waste itself is diverse. A whole series of technical discoveries and improvements have made the waste of one production process the raw material for another type: the extraction of dyes, explosives, medicines (aspirin, phenacetin, pyramidon, etc.) from coal tar, which is a waste product of coking—Coarse refuse

From a material point of view, there are no grounds to object to the widespread utilization of various waste. On the contrary, the utilization of waste provides an economic basis for sanitary measures for the neutralization of waste. It is important at all stages of waste processing to uphold the sanitary point of view with the goal of paralyzing the danger that waste represents for humans. To this end, sanitary authorities must be well acquainted with all possible methods of collection, removal, utilization, and neutralization of waste, choosing from them those that can provide the greatest sanitary effect.